KEMiwos
PROCEEDINGS
EIGHTH PACIFIC SCIENCE CONGRESS
PACIFIC SCIENCE ASSOCIATION
1953
VOLUME III.
OCEANOGRAPHY
Published by the
NATIONAL RESEARCH COUNCIL OF THE PHILIPPINES
NIVERSITY OF THE PHILIPPINES’.
QUEZON CITY, PHILIPPINES
A ite 1957
Given in Loving Memory of
Raymond Braislin Montgomery
Scientist, R/V Atlantis maiden voyage
2 July - 26 August, 1931
AK KK KK KK
Woods Hole Oceanographic Institution
Physical Oceanographer
1940-1949
Non-Resident Statf
1950-1960
Visiting Committee
1962-1963
Corporation Member
1970-1980
KKK KKK
Faculty, New York University
1940-1944
Faculty, Brown University
1949-1954
Faculty, Johns Hopkins University
1954-1961 ©
Professor of Oceanography,
Johns Hopkins University
1961-1975
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PROCEEDINGS
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EIGHTH PACIFIC SCIENCE CONGRESS
OF THE
PACIFIC SCIENCE ASSOCIATION © —
Held at the University of the Philippines
Diliman, Quezon City /
16th to 28th November 1953 6 =
UNDER THE AUSPICES
OF THE
NATIONAL RESEARCH COUNCIL OF THE PHILIPPINES
AND THE
REPUBLIC OF THE PHILIPPINES
VOLUME III
OCEANOGRAPHY
fo
NATIONAL ee HReGERCHL OF THE PHILIPPINES
nace te a THE PHILIPPINES
QUEZON CITY, PHILIPPINES
1957
EigutTH PaAciric SCIENCE CONGRESS
FourTH FAR-EASTERN PREHISTORY CONGRESS
COMMITTEE ON PUBLICATION AND DOCUMENTATION
Chairman: Dean PATROCINIO VALENZUELA
Co-Chairman: Prof. GABRIEL A. BERNARDO
Dr. Jose P. BANTUG
Prof. H. OTLEY BEYER
Mr. PAUL BIERSTEIN
Dr. JesusA A. CONCHA
Mr. Haroitp CONKLIN
Mrs. ARACELI P. GAFFUD
Mrs. Pirar A. HALLAZGO
Prof. Socorro P.
Dr. ArcHre Hess
Mrs. Luz B. LARDIZABAL
Mr. E. ArsENIoO MANUEL
Mrs. Rosario MENDOZA
Dr. GILBERT S. PEREZ
Mr. RaMON SAMANIEGO
Mr. JosE ‘TEVEs
VILLA
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ae lige
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ees
CONTENTS
VeLUME Jil
OCEANOGRAPHY
Resolutions Adopted in the Eighth Pacific Science Congress Concerning
OCeanoomap ly aascreber wh Matree mentor eaten steel repent ey cance er. seatat ci aeal seeee Minas
Report of the Standing Committee on Oceanography of the Pacific.
By Thomas G. Thompson and John P. Tully.
Part I. General Statements and Recommendations .............
Part II. A Summary of Pacific Oceanography, 1949-1953 ......
Part III. Reports on Activities of Specific Countries on Research
OrraniZation sens) o:c)cl2ds POU Relay AS UET tats aU sc: ee, mE
DIVISIONAL DISCUSSIONS: PROBLEMS IN THE DEVELOP-
MENT OF METEOROLOGY AND OCEANOGRAPHY
TN EGE ae A CHG Ceo, ocerparepe eatery episye ss Lies
SYMPOSIUM ON EXPLOITATION AND UTILIZATION
OF PRODUCTS FROM THE SEA
HSEOCCeCIN Se SM mEt eee oe Wek! ee mabe Sy EEE Se ee Ey i
ibiologicaleOceanosraphy. By Wi. Aur Clemens) ja. 5.5.6s,- 2 o2eens shen.
A New Approach to the Study of Marine Resources—the California
Cooperative Oceanic Fisheries Investigations. By Robert C. Miller
Nourishment of Central Pacific Stocks of Tuna by the Equatorial Cir-
culationa system sBy Oscars Hs Setter: iti. e alse ee
Development and Conservation of the Tuna Fisheries of the Pacific.
By Milner B. Schaefer
Recent Studies on Tunas and Marlins in Japan. By Hiroshi Nakamura
and Yoshio Hiyama
0. 0'9%0 0) ORONO 0 DOGS OPO" oO 0 DiS 6) 9o°0 Gioo%D Of O10 OO. b O00 onoO
o/t s)he le) (oko) jelelelielie fel esialie) (sie eek eiie}iahie) a) leleife"\s)ehiene) ejeheils| efullceve levee
Are the World-wide Declines in Sardine Catches Related? By John C.
Marr and James E. Bohlke
The Products of the Sea and Their Exploitation and Utilization in Pa-
kistan. By M. R. Khan
Some Factors Bearing on the Utilization of Marine Products of the
West Coast of Canada. By Neal M. Carter
Fabrication, Definition et Reglementation de la Sauce de Poisson -Viet-
namienne “Nuoc-Mam.” Par J. Guillerm et A. Vialard-Goudou ..
Studies on Agar-Agar in Japan. By T. Yanagawa and K. Tanii ....
A Report on the Studies Made in Japan on Pearl Culture. By Yoshiichi
ole: ishe hey el aiie) ole) eve ehelie/aoyieileljie’ isi keh a, ehejie! ee) 0 jeletieei-e! felte
00000 0000 O00 66 30 0’ Os0o 090 6-5 050.5 dlolo.o Oe c.O ono
IVEAGS UT gy ctees es cspae OO seep. halt, orale ieeeeaaes cece eed re eae atorcke
Fundamental Studies on the Fish Lamp. By N. Y. Kawamoto ......
Coaction in Lamp-Communities. By Hiroshi Maeda .................
The Hake Fisheries off the West Coast of Chile. By Erik M. Poulsen
PAGE
115
116
121
126
131
149
165
183
189
200
208
215
225
229
234
241
Report on the Algae of the Chilean Seas. By Hector Etcheverry-Daza
The Hisheries of ‘Chile:) By B: s4#:Osonio-Mafallls)..02... .see eee
Preliminary List of Chilean Fishes and their Vernacular Names.
By Fernando ‘de *Bueny 3... Suen ae ee eit ee eles eras uc. « Merutonaiore
Edible Shellfish of the Chilean Coast. By Francisco Reveros-Zuniga ..
Notes on the Commercially Important Fishes of Chile. By Parmenio
Be SVATIOZ. CS) 2 larreerataoe snes Soo Sea ee a ia, a fae oA Tle rR ee RU
Oceanographical and Fisheries Research in India. By N. K. Panikkar
Oceanography and Fisheries. By G. L. Kesteven ...................
Factors in the Utilization of Canada’s Pacific Marine Resources. By J.
Tu: Hart: parte se oacc ast aoe. AS es BO
Poisonous Fishes and their Relationship to Marine Food Resources in
the Pacific: Area. ) By, Bruce |W... Halstead) ccen eee eet
Some Aspects of Fisheries Problems in the South Pacific Area. By A.
He SORE KHOOMN Sette cP eee teen crm ance cel eta Smt eusnc tars Nace meet ance enon
SYMPOSIUM ON MARINE PROVINCES IN THE
INDO-PACIFIC REGION
Awardees ot. the WINTIS COL Subvyentionsas ss eae eee ee en
PTOCCECIMES: se oic eyes eiove ale eearel ay seo or cual cities Sea aneiiy eikewals els elt nee Re cine actin aa
The Nature and Evolution of the Hawaiian Inshore Fish Fauna.
By: Wilhlam A. Gosline. 3. acces cccctm mee copa natal oy age pn ane crates eee ee rae
Marine Provinces of the Indo-West Pacific. By A. W. B. Powell .
An Outline of the Distribution of Pacific Deep-Sea Animals. By Anton
Bers Bruun’. & ois sccyecs ke lece lib ells oa) ae toyhe «Sau seen ey ae SRNR 5 RI
Deep-Water Biological Provinces of the Indo-Pacific. By Rolf L. Bolin
Some Outlines of Plankton Concentration in the Eastern and Tropical
Pacific. aby ~Martin yw. Johnson jc.0- ear soe lee ei eae
Distributional Provinces of Marine Bryozoa in the Indo-Pacific Region.
By, Yaichiro; Okadavandy Shizuo Mawatan, 43532 9.ere ee oe
The Distribution of Polychaetes within the Indo-Pacific. By G. A. Knox
A New Approach to the Distribution of Fishes in the Indo-West Pacific
Area... By. Leonard :P. ‘Schultz. choc. coin eee es oe ee
The Zoogeographical Distribution of the Indo-Pacific Littoral Holo-
thurioidea.. By Jose S..Domantay hae. are. eee cere ate tele cher
Distribution of Marine Fishes in South East Asian Waters. By J. D.
FY. \WHardenberg tiny ..f) 3% tees. eh, SASS 2 eR RR ORES eet
An Analysis of the Pelagic Bird Faunas of the Indo-Pacific Oceans.
By/-Dauke Serventy flac) let. My iat Sh Sa, WAR eksoots clon, Se wee
Some Distribution Patterns Represented by the Marine Algae of Nha-
trane BayisVaetnam. 7 By Ea ValesDawsoml.rie is -liirsto eee
Some Problems on Marine Biogeographical Micro-Provinces Surrounding
Japan. By Tadasige Habe, Tokubei Kuroda, and Denzaburo Miyadi
li
PAGE
246
253
266
280
287
294
303
314
321
301
337
338
347
359
365
373
379
391
403
413
417
457
461
489
493°
The Marine Mollusca of the Kermadec Islands in Relation to Molluscan
Faunas in South West Pacific. By R. K. Dell ..................
The Geographical Variation of Early Embryenic Processes in Marine
Eggs. By Alexander Wolsky .......+2- 22.6 esecee sees teenies
SYMPOSIUM ON GENERAL CIRCULATION IN THE PACIFIC
IPYVOCECOINES) o.48 Sa eee ts oes et oa hi oh) CE clots ensers
A Theoretical Study on the General Circulation of the Pacific Ocean.
By LO IBGE ey ae tes op oe PAC O MOS me coo sno mae PHnaeo AIbO pao moe
A Contribution to the Theory of Upwelling and Coastal Currents.
IRy Joy IehiCe keen gash ooloamhd oma bocnb soo gag moms s Mods 6 con 6.55
Surface Waters Off the Canadian Pacific Coast. By J. P. Tully and
eae Ati DOC 25 |e oe coe Soul ee RRA De OREN Oh MER. aE Ae
Circulation Near the Washington Coast. By Clifford A. Barnes and
Robert aGasPaquetten. actarevs coeur aes mooteeperetrret a att oar
U.S. Navy Contributions to the Study of Pacific Circulation. By John
Lyman
On the Variation of the Kuroshio Near the Japan Islands. By D. Shoji
andy. pSuddeda «45 mone enmrkie Al. Sede. Es aall. Shad) 8 PAE
Sedimentation in the Deep Sea. By Hans Pettersson ................
Some Characteristics of Sea Water Structure. By John P. Tully ..
On the Circulation in the North Pacific in Relation, to Pelagic Fish-
Cesar yo Vier elaintal key WIGAN ar recca tosis cscs ie hve peiemenees sue a oe oes
The Topography of the Sea Surface in the Region of the Philippines.
By Herbert W. Graham
Recent Oceanographic Exploration in the North and Equatorial Pacific
Ocean | Ve VWiaEVenbiss NVOOSbERTR ASIF eS « sche ods cs aus had aed on
Basin Waters of South California. (Abstract) By K. O. Emery ....
An Oceanographic Model of Puget Sound. By Clifford A. Barnes,
Johnet tincolngand. MaurticesRattray voice ase Funes Onis ene
Daily Seawater Observations on the Pacific Coast of Canada. By H.
Ain’ -L IOUS EPR iS Bite ie Oreo ae oc ecics CHR Ret Oe Ree CRE near grin en ek ee
A Study of Local Variability in Marine Sediments. By Richard G.
Bader
Secular Variation of the Annual Mean Sea Level Along the Japanese
Coasts. IBy Wilememiaeneny OKRA G Oho ogg mee cia to De mee > Comer
Submarine Canyon Investigations. (Title only) By Francis P. Shepard
Surface Temperature and Salinity in the Southwest Pacific Ocean.
(CAlbarrpmce)) | 1Byy ID Wile (GeneaeIe ohooh bu choo coomod ou dado an adgicoS
Secular Trends at East Australian Coastal Stations: 1942-1952. By
ID) Ap TRG yo) a ores eum aot erie ea ee eee eee Rae cme Coren ERO cero o.ccn chai o-cbo'o.
Recent Developments in Tidal and Tidal Current Measurements. Con-
imibution trom the U.S. Coast and Geodetic) Survey ..-2-5-..:.....-
On the Minimum Oxygen Layer in the North Pacific Ocean. By Takeo
TREAT ONO ena cea te eee Ole orcear aot Fi sieiin sal atone oh ooo carck arocio Gini Ren ERO
A Study on the Property of the Coastal Water Around Hachijo Islands.
By Yasuo Miyake, Y. Sugiura and K. Kameda
On the Oceanographical Conditions of the Sea near the Fixed Point,
153°E, 39°N, in the North Pacific Ocean. By M. Nakano, M. Koi-
zumi and J. Fukuoka
elivjcele:lehteieltetiotiaWel « (0) ofiee) e eniehiel ©) eloleniel cle el(e/> els, teg.w ties (oatiol =tslke
Distribution of Copper and Zine in Sea Water. By Yoshimi Morita ..
Abnormal Summers in the Peruvian Coastal Current. By Erwin
Schweigger
S} elllaftel'e! «| eiiel ie veh ene Jeliehienisfielohejle)ie) iejve ulielielte’ 0° 0) Te)ie)\e. = 1a) =) eee! ef el lejsa) (ole ene) when arae,
Quantitative Determination of Tungsten and Molybdenum in Sea Water.
By Masayoshi Ishibashi, Tsunebobu Shigematsu and Yasuharu Na-
kagawa
‘ei iv,-s! (otto! ie) sinless) \e: 0) cel 9] /e: e' \e) ejlevielie] lo}eiie) elie! fee oli) ofjeleiveisel/ecalle jeje) J /6)e),") lia; omen ilomememe
A Study on Temperature and Salinity of the Surrounding Waters of
Taiwan. By Chu Tsu-Yao
Cee SC eC ee
On the Fluctuation of the Kurosiwo and the Oyasiwo. By T. Nan’niti
A Report on the Oceanographical Observations in the Antarctic Ocean
Carried Out on Board the Japanese Whaling Fleet During the
Years 1946-1952. (Abstract) By Masao Hanzawa and Takeo
A LSiG Tcl cb kok: Waeey x apes CN Ue gir WY ts inate or a’ Sey Ey eae ep rd er me PRIA ME 41S ALANA 16 (0,0
A New Japanese G. E. K. By Suda, Kuroda-Masao, D. Shoji and Sawa-
yanagi-Fumiwo
ee fel fej ce te) ferte;le\te) ee) ©) (efiejjej le «lo. feuje (e eisel ieee te: jalie .efie,1@! ase) ie) 1ei1e) oe) (0/16! (e!n0)/1 8110), @)
PAGE
[Note: The other papers in Oceanography and those of Zoology are included
in Volume III A.]
lv
OCEANOGRAPHY
Organizing Chairman: Dr. D. V. VitLapotip, Director, Bureau of
Fisheries, Manila.
Secretary: Mr. ‘TEoporo G. Mecta, Bureau of Fisheries, Manila.*
RESOLUTIONS ADOPTED IN THE EIGHTH PACIFIC SCIENCE
CONGRESS CONCERNING OCEANOGRAPHY
STANDING COMMITTEES
5. That the Standing Committees on Meteorology of the Pacific,
Oceanography of the Pacific, Pacific Entomology, Pacific Conservation,
Museums in Pacific Research, Soil and Land Classification in the Pacific
Area, Forest Resources of the Pacific Area, Crop Improvement in the
Pacific Area, Animal Improvement in the Pacific Area, aearopology
and Social Sciences in the Pacific be continued.
JOINT DIVISIONAL RESOLUTIONS
I. Geology, Oceanography and Meteorology
The Congress notes the efforts now being made to provide for the
establishment of an international geophysical institute in the Hawaiian
Islands as a center for the investigation of problems related to the chem-
istry, physics and mathematics of the earth, sea and atmosphere and their
roles in Pacific environmental relationships.
The Congress believes that an institute in the sense envisaged
would greatly improve the opportunities for investigation of important
geophysical problems.
DIVISIONAL RESOLUTIONS
Oceanography
1. ‘The Congress notes with interest that the oceanographers attend-
ing the Eighth Pacific Science Congress propose to establish an Oceano-
graphic Institute of the Pacific.
* Present address: Bureau of Agricultural Extension, DANR, Manila.
1
2 EIGHTH PACIFIC SCIENCE CONGRESS
2. ‘The Congress strongly supports the proposal, recently examined
by the special UNESCO meeting of consultants on oceanography, to
create a legally constituted inter-governmental organization for oceano-
graphic research in the Indo-Pacific region.
3. The Congress urges member countries (a) to exert every means
to develop research programs upon which may be based sound policies
for increased development and wise use of marine resources, (b) to de-
velop the fullest international cooperation in the management of marine
resources so that they may be maintained permanently.
4. The Congress draws attention to the following types of ocean-
ographic study which can be maintained at a small cost, and whose re-
sults when correlated with other available data can provide large re-
turns: (a) Daily observations of surface sea water temperature and sa-
linity which can be made at light-stations, and by commercial shipping
lines. “The work may be extended to daily observations of the nutrient
and respiratory elements, and the state of the sea. (b) Study of specific
organisms of academic or economic interest in the locality. There are
many species which have been taxonomically described, but whose life
history, habits and economic value are unknown.
5. The Congress commends the excellent research work of the Bu-
reau of Fisheries of the Philippines and respectfully suggests to the Gov-
ernment of the Republic of the Philippines that it explore the possibili-
ties of establishing further oceanographic and fish culture research
through the provision of extended facilities.
REPORT OF THE STANDING COMMITTEE ON
OCEANOGRAPHY OF THE PACIFIC
Prepared by
THomas G. THOMPSON,! Chairman; and
Joun P. TuLty,? Secretary
PART I
GENERAL STATEMENTS AND RECOMMENDATIONS
The greatest impetus given to the science of oceanography in the
past few years, other than man’s unquenchable thirst for new knowl-
edge, has been the desire to increase the food resources of the world
which have their origin in the sea. Prior to World War II only a rela-
tively few countries were concerned with the study of oceanography,
even though all of the Pacific Science Congresses have continually
stressed the importance of exploring and exploiting the seas as a source
of food, in order to feed rapidly growing and sometimes hungry popu-
lations. The necessity for looking to the sea, which covers about
seventy per cent of the surface of the earth, as a source for additional
food is now being realized by many political leaders, and other far-seeing
individuals in many countries. For the Pacific area this has been espe-
cially significant since the 7th Pacific Science Congress. Stressed also
is the importance of collaboration for research, conservation and the
free exchange of scientific information.
The seas may be searched far and wide, shallow and deep to find
the habitats of the fish. This is the historical method. Fish are where
you find them. ‘This method is not very efficient for the fish are here
today and somewhere else tomorrow.
If dependence is to be made upon the fisheries for an assured food
supply, the optimum conditions for each particular fishery must be
known as well as when and where such conditions will occur. The
adaption of proper and economical fishing methods for the different
fisheries in various areas must receive detailed attention and study, al-
though the metheds of the commercial fisheries are not in the realm
of oceanography.
The oceanographer reasons that the fish will seek those parts of
the sea where the food of the fish is most plentiful, where optimum
1 Professor of Oceanography, University of Washington, Seattle 5, Washington, U.S.A.
* Oceanographer in Charge, Pacific Oceanographic Group, Nanaimo, B.C., Canada.
9
>)
4 EIGHTH PACIFIC SCIENCE CONGRESS
conditions of fertility occur for production of such food, and where
the climate of the sea is most suitable. In other words, the oceanog-
rapher must provide information as to the nature and extent of the
best pastures and the most desirable sea climate. With such oceano-
graphic information, expressed in the form of charts, the commercial
fisherman can function economically and efficiently. This oceano-
graphic method is in sharp contrast to the so-called historical or hunting
method.
As an example of the oceanographic method, it is deemed desirable
to outline its application to recent tuna investigations. ‘The tuna prefer
ocean waters where the temperatures are higher than 15°C. and the
salinity is greater than 32°/,.. The tuna also require a plentiful supply
of smaller fish on which to feed. ‘These small fish are plankton feeders
and are found in regions of upwelling near the continental coasts, or
around islands, or in some of the ocean currents. These regions of
upwelling supply the necessary nutrient material which is essential to
plankton growth. Tuna are found in the broad tropical belt of the
ocean and can be expected to migrate into some parts of the temperate
regions during the summer months. The search for tuna is narrowed
to salubrious climates which are well stocked with plankton feeders.
Thus the assumption may be made that if the conditions suitable for
plankton are known in the warmer seas, there tuna will be found.
Hence the oceanographic conditions of the plankton are studied in order
to find the tuna.
In this oceanographic approach some progress has been made. It
is known that the basic focds are the respiratory elements, oxygen and
carbon dioxide and the various nutrient salts such as nitrates, phos-
phates, silicates, etc. ;
The respiratory elements are plentiful everywhere in the upper
100 meters of the ocean, but the nutrients are often depleted, except
in the regions of upwelling, where they are replenished from the cool
depths. Physical oceanographic studies indicate that such regions occur
along the coast lines, and around the islands. Here the phyto-plankton
is plentiful, and provides food for the zooplankton, which in turn feeds
the small fishes on which the tuna feed. Evidently tuna should occur
in the warm waters on the lee side of coasts and in the vicinity of up-
welling in the equatorial currents. ‘This has been found to be generally
true. However, they also occur in many parts of the open ocean where
plankton and the plankton feeders are sparse, and so the simple theory
of the food chain is not the only explanation of the fishery.
Recently it has been learned that great concentrations of plankton
exist in the cold water below the thermocline, over all the known seas.
This plankton layer is deepest in the tropics and shallowest in the arctic
REPORT ON OCEANOGRAPHY 5
and antarctic and it sinks by day and rises at night. This deep plank-
ton layer contains many sizable forms of euphausiids and small fishes,
and it is suspected that some of the tuna feed there. If the plankton
rise above the thermocline into the warm layers, it would be invading
the habitat of the tuna, and they could feed on it. If the plankton
rose only to the thermocline, but not through it, it is possible that the
tuna would find it. They could make forays into the colder waters,
and return to the upper warm waters between feedings. But if the
plankton is always well below the thermocline it may be doubtful if
the tuna would find it.
Oceanographic data should designate the areas where the deep
plankton rise to or through the thermocline. Echo sounders reveal the
depths at which the plankton layer exists and also indicate the possible
presence of tuna. New types of gear for deep fishing need to be devel-
oped or some method devised for luring the fish within the range of
existing gear.
This is the oceanographic method. ‘Yo learn the requirements of
the fish; to determine when, where, and how these occur; and then to
seek the fish in the most likely places, at most suitable times, and where
necessary develop methods of detection and fishing. ‘The last steps are
simple, when the biology and oceanography are complete, as shown by
the investigations of the Conseil Permanent pour l|’Exploration de la
Mer, in the North Sea.
This reasoning would be sufficient if extensive knowledge of the
plankton were known as well as many details concerning the properties
and characteristics of the waters. For most of the Pacific this knowl-
edge is very incomplete. One is confronted with the threefold task of
exploring the ocean for tuna, solving the living habits of plankton and
charting the properties and characteristics of the water masses.
During the span of the Pacific Science Association, since 1924, the
Pacific Ocean has been explored. Many oceanographic expeditions have
defined the water masses, charted the currents, recognized the properties
of the water, and studied the fish and the plankton. The major water
masses, the principal currents, and the generally productive and unpro-
ductive areas are known. However, detailed knowledge is very meager.
The cycles of temperature, salinity, and productivity, the variations in
currents, the migration routes and fluctuations of the fisheries are the
present concern.
Research in oceanography is expensive. It requires expensive ships,
expensive equipment, highly-trained personnel and a large operational
investment. ‘The specialized agencies of the United Nations have real-
ized this and the Food and Agriculture Organization has during the
past five years sponsored the Indo-Pacific Fisheries Council, an associa-
6 EIGHTH PACIFIC SCIENCE CONGRESS .
tion of 16 member governments of South and East Asia, while UNESCO
has, besides providing substantial grants-in-aid to enable plankton work-
ers to attend the forthcoming Symposium to be held in connection with
the 5th IPFC meeting in Bangkok, convened, jointly with FAO, the
meeting of consultants held immediately prior to this Congress to study
the feasibility of promoting a co-operative international oceanographic
project for the Indo-Pacific region. It will therefore be seen that there
is a tendency for a banding together by many countries of the Pacific
area for the study of the sea. Nations that have been dependent solely
upon their land resources are now studying their fisheries and exploring
their seas, while those nations that have pioneered in oceanographic
research have increased their efforts many fold.
At the first meetings of the Pacific Science Association in New Zea-
land, the report of the chairman of the Standing Committee on Oceanog-
raphy consisted largely of a review of the principal advances that had
been made in instrumentation. ‘The countries of the Pacific were be-
ginning to recover from devastating war and the universities and gov-
ernmental research agencies were still in the process of readjustment or
reorganization. Compared to the present situation little could be said
at that time about research accomplishments or planned programs of
research.
In most countries oceanography is undertaken by the senior govern-
ment, in the Fisheries or the equivalent department, with close coopera-
tion of the navy, and the hydrographic and meteorological services.
In practically every case the work is directed by a National Committee
representing the services, the allocation of effort, resources and _per-
sonnel. ‘The outstanding exception is the United States, where oceano-
graphic efforts are divided amongst a number of independent agencies,
with the universities now tending to play the major role.
One of the important resolutions of the 7th Congress was one
urging the establishment of centers for oceanographic education and
research in the Pacific area. At the present time such institutions exist
in Canada, Hawaii, Japan, and the United States, with full university
connection, where contact with experts of all the sciences which can
be applied to the study of the sea is possible, and where full library
facilities are available. At these universities are oceanographic institu-
tions or academic departments of oceanography. ‘These centers are pro-
viding the initiative, inspiration and encouragement necessary to develop
young men for the task of advancing oceanographic knowledge. This
trend toward the establishment of oceanographic centers in universities
is evidenced in other countries of the Pacific area.
REPORT ON OCEANOGRAPHY th
The greatest deterrent to the development of oceanography at
present is the lack of trained personnel. With the growth of the cen-
ters of oceanography the problem of personnel will gradually be solved.
All the peoples of the Pacific are dependent upon the sea, yet the
average person is wholly ignorant of this medium. ‘There should be
established in the schools and universities of the several nations elemen-
tary courses dealing with oceanography. Such courses would be purely
of an informative and cultural nature and presented in order to give a
general knowledge of the oceans and the many organisms contained
therein to the occasional student so that he would be inspired to resume
further studies in one of the fields of oceanography.
Since the war many feliowships have been made available which
enable students to study in countries other than their own. Experience
to date indicates that these fellowships create potentialities for better
international understanding than any other system yet devised. ‘This
Congress should go on record as urging the establishment of further
fellowships, particularly in the several phases of oceanography.
A standing committee of the Pacific Science Association usually con-
sists of six to ten members. ‘The chairman is appointed by the President
of the association and has the power tc act and name the members of
his committee. He works in cooperation with the chairman of the
local organizing committee in the preparation of programs and plans
for a forthcoming Pacific Science Congress and with the secretariat on
other matters. This general plan of operation has many desirable
features.
In forming the Standing Committee on Oceanography there are
many factors to be considered, chief among which are to secure a proper
representation of the various specialities in oceanography and a saatis-
factory geographic distribution of the members. In selecting the mem-
bership of the committee the chairman has sought the advice of many
colleagues. He has received suggestions from representatives of govern-
mental organizations, and some oceanographers, eager to further the
advances of oceanography, have volunteered their services. Sometime
ago the chairman saw the advisability of sub-dividing the committee in
order to insure a better specialization of geographic representation.
The Standing Committee on Oceanography at present consists of 32
members, which includes the chairman, the secretary and three sub-
committees of ten members each. The subcommittees cover the fields
of physical oceanography, oceanic biology and the fisheries, and each
subcommittee is headed by a chairman.
As the result of experience in forming the present committee, cor-
respondence with several members of the committee and with oceanog-
raphers not affiliated with it, the chairman and the secretary have
8 EIGHTH PACIFIC SCIENCE CONGRESS
become convinced of the desirability of forming an oceanographic so-
ciety of the Pacific. It is suggested that such a society be part of the
Pacific Science Association and its meetings would be an integral part
of a Pacific Science Congress. ‘The officers and executive committee of
such a society, elected by popular vote of the membership, would func-
tion for the association in much the same manner as the present stand-
ing committee. “Through membership in such a society every oceanog-
rapher would have a voice and the privilege of active participation.
The present standing committee may be criticized as being more or less
of a closed system. More than twice the numbers now comprising the
Standing Committee were recommended for or volunteered for member-
ship. Then again there are a number of young men just beginning
their careers in oceanography who would undoubtedly profit by affilia-
tion with such an organization. This would also be true of oceano-
graphers who are citizens of nations where scientists are relatively few.
Such a society could sponsor a much needed oceanographic publication
for the entire Pacific area, provided funds could be obtained, in which
oceanographers could publish the results of their finding. Here also
would appear information of current activities, periodic abstracts of out-
standing articles published elsewhere and a current bibliography. It is
recommended that such an organization be considered by this Congress.
The 7th Pacific Science Congress meeting in Auckland and Christ-
church, had a marked catalytic effect on oceanographic research in New
Zealand, and those who came from afar to attend the Congress learned
much from their New Zealand colleagues. It was an education to
have seen this delightful country and to have been received so generously
by its charming people. It is hoped that the oceanographers of the
Philippines will receive a similar stimulus and those that have come
from afar will be inspired by seeing the Philippines and meeting with
the citizens of the country which has played a major role in recent his-
tory.
It seems fitting for the chairman and the secretary of the Standing
Committee on Oceanography to express their appreciation for the excel-
lent cooperation received from all members of the committee. It has
been a real pleasure working with Dr. D. V. Villadolid, chairman of
the local organizing committee on oceanography and also chairman of
the subcommittee on fisheries. Through his untiring efforts an excel-
lent program has been organized and it promises to surpass even those
of previous congresses. ‘To Dr. Villadolid and his associates the Stand-
ing Committee expresses its profound thanks and appreciation for their
many efforts.
REPORT ON OCEANOGRAPHY 9
PART II
A SUMMARY OF PACIFIC OCEANOGRAPHY, 1949-1953
Prepared by
Tuomas G. THompson, Chairman; and JouN P. TuLty, Secretary
An attempt will be made to summarize briefly some of the activities
and results of oceanographic research since 1949 as reported by the mem-
bers of the Standing Committee. This summary will be augmented, in
some cases, by more detailed reports outlining the programs and accom-
plishments of a specific country or research organization, and are given
as Part III of this report. However, much of the important research
that has been conducted will be presented to the congress in the sympo-
sia that have been organized under the direction of members of the
Standing Committee on Oceanography, and the Philippines Organizing
Committee.
AUSTRALIA
The hydrological cycles in the sea around Australia have been stu-
died, the surface and water masses in the Tasman Sea have been identi-
fied, and the oceanography of some Australian estuaries have been re-
lated to the productivity of oysters. Regular observations between Aus-
tralia and Antarctica, and at Macquarie and Heard Islands, have been
made. A source of deep, very saline water has been found by the Dis-
covery Expedition in the ‘Tasman Sea, which appears to move eastward
counter to the circumpolar drift.
A number of oceanographic cruises to 100 miles of the southwest
coast were taken in the Fisheries Research Vessel ““Warren’’ to examine
the properties of the water. The R.R.V. Discovery II examined the
properties along the five lines of the southern coast. Surface observations
are being secured fortnightly from Australia to New Zealand by the
regular passenger ship 1.S.M.V. Wanganella.
‘The temperature and salinity characteristics of the surface Tasman
Sea water masses have been determined, and their seasonal variation in
position will be followed in the future, particularly as they affect coast-
al waters.
A contribution to the knowledge of estuarine hydrology has been
conducted by D. J. Rockford and the work is being continued by de-
tailed dynamic and productivity studies of selected estuaries. This re-
search is primarily directed toward oyster production.
The Australian National Antarctic Research Expedition has main-
tained physical and biological research stations at Macquarie and Heard
10 EIGHTH PACIFIC SCIENCE CONGRESS
Islands since 1948. Hydrological and biological programs have been
carried out, and oceanographic observations have been made between
Australia and the Islands, each year, by the relief vessels. “The Expedi-
tion is to be extended to the Antarctic mainland in the Australian sector.
The biological oceanographic studies have been concerned with de-
veloping the unutilized or little utilized aquatic organisms. This includes
the discovery of the stocks, fishing tests, life histories, and identification
of tuna, clupeoids, carangids, and archibenthic fishes, as well as help
surveys.
The Division of Fisheries of the Commonwealth Scientific and In-
dustrial Research Organization carries out a research program in Hy-
drology and Planktology at its Cronulla headquarters, and at five field
stations. “This work includes sampling at various coastal stations in
eastern and western Australia, which has revealed the hydrological cycles
at various latitudes, and a long term trend in the properties and produc-
tivity in Eastern Australian waters.
In the fisheries, studies have been made of stock identification, life
histories, natural fluctuation, and effects of fishing. ‘These fisheries in-
clude barracuda, salmon, humpback whale, western crayfish, sea mullet,
scallop, school shark, tiger flathead, white bait, and other indigenous
fishes.
Considerable work has also been done on the acclimatization and
culture of rock, pearl and Japanese oysters, the introduction of fresh-
water trout, and the enrichment of inland waters. Estuarine ecology
has received some attention with a view to increasing fish production.
No institution in Australia gives special training in oceanography,
but the Department of Zoology in a few Universities gives lectures on
marine organisms and ecology; and there are small research projects on
marine animals for post graduate students.
CANADA
A series of surveys has been undertaken for about 500 miles of the
coast to examine the currents and the properties of the water to a depth
of 1000 metres. This area of British Columbia is where the North Paci-
fic drift divides, part flowing north to form the Alaska gyral and part
south to form the California current. Coupled with the Marine Life
Research Surveys off the coast of the United States, this work provides
for the first time a realistic picture of the detail of this great divergence
which has been recognized for a long time. The currents are weak (less
than 10 miles per day) and mostly eddies.
The salinity structure is definite and appears to be permanent.
There is an upper zone of low salinity water to about 100 metres depth,
a deep zone of greater salinity, separated by a boundary or transition
REPORT ON OCEANOGRAPHY 11
layer of ten to 100 metres thickness. In late winter the temperature
stratification is similar to the salinity. When the surface waters are
heated in the spring a warm layer is formed which gradually deepens
and becomes more marked as the season advances. When autumn cool-
ing occurs the warm layer loses heat, but continues to deepen until it
coincides with the salicline in late winter. This area is being continual-
ly monitored by regular bathythermograph observations from the
weather ship on Station Peter.
The principal interest is in the coastal waters and the many bays,
sounds, inlets and straits which are the dominant feature of the Pacific
coast. ‘The area is divided into natural regions. Each region 1s sur-
veyed at frequent intervals throughout a year or more, uatil the prop-
erties of the water and the mechanisms of circulation, and their sea-
sonal variations are revealed. These are then related to daily observa-
tions of surface sea water temperature, weather and run-off that are be-
ing made concurrently around the coasts. These daily observations then
serve as continuing indices of the oceanographic conditions. Both the
oceanographic conditions and the daily observations have been success-
fully related to some of the fisheries.
The prediction and control of industrial and domestic pollution in
coastal areas had become a major oceanographic concern. As new indus-
tries are established their effect on fisheries is forecast and the disposal
of sewage adjusted to avoid harmful pollution.
This work is under the direction of the Joint Committee on Ocea-
nography in Canada, which all government departments interested in
the sea, pool their requirements and resources. The Committee directs
the work of a group on the Atlantic Coast and another group on the
Pacific Coast, in physical and chemical oceanography. The Fisheries Re-
search Board of Canada operates five stations studying fisheries and two
stations studying the utilization of marine products. In addition there
are a number of National and International Groups conducting ocean-
ographic and fisheries research in particular areas, and on particular
problems.
The charting of coastal waters and forecasting of tides and tidal
currents is done by the Hydrographic Service.
The Institute of Oceanography at the University of British Colum-
bia is the only place where Oceanography is formally recognized, al-
though a number of universities conduct sea researches. The Institute
offers post-graduate courses in the application of the various sciences
in the sea leading to advanced degrees in those sciences.
Publication is provided in the Journal of Fisheries Research Board
of Canada, and a manuscript series from each oceanographic group and
the Institute of Oceanography.
12 EIGHTH PACIFIC SCIENCE CONGRESS
CHINA
In spite of tremendous difficulties there are some observations of
sea water temperature, and some fisheries studies being made. ‘There are
plans to establish a research center for fisheries and oceanography which
will unite all the work.
DENMARK
The Galathea Expedition fished in the bottoms of the Kermadec,
Solomon, Banda, Java and Philippine deeps and found a variety of ani-
mals and live bacterial cultures right down to 10,000 metres depth. Tem-
perature and salinity samples were also taken, and production of organic
matter was studied by means of Carbon 14.
FOOD AND AGRICULTURE ORGANIZATION OF THE
UNITED NATIONS
This organization sponsored the creation of the Indo-Pacific Fish-
eries Council. It is evident that oceanographic research in the tropical
regions of Asia has been scanty. The lack of knowledge in the Western
Pacific and Indian Oceans is one of the largest gaps in the scientific
exploration of the earth. ‘The Indo-Pacific Fisheries Council has under-
taken to promote the exploration and utilization of the fisheries of this
region by member governments. Oceanography is an essential feature
of the program. Australia, India, Indonesia, Japan, New Caledonia and
the Philippines have conducted oceanographic programs in their own
coastal waters. The Galathea Expedition from Denmark explored some
of the waters of the Indian and Western Pacific waters, particularly the
great depths. However, it seems that no organization is ready to under-
take the over-all sustained exploration and research which is required
to exploit the potential food supplies in these seas. The Indo-Pacific
Fisheries Council proposes that all the countries in the area coordinate
their efforts and pool their results so that each may profit from the work
of all. A meeting which some of you attended was held a few days ago
to discuss this project. If such a plan can be put into effect, it may well
equal the excellent work of the Conseil Permanent pour I’Exploration
de la Mer, and add materially to the food resources of southeastern Asia.
The growing interest in oceanographic research by the countries of the
south and southwest Pacific and the activities of the Indo-Pacific region
seem most promising.
GREAT BRITAIN
Trom October, 1951, to January, 1952, the Royal Research Ship Dis-
covery II made oceanographic surveys between Australia and Antarctica.
The primary object of this work was to fill in the gaps left by the pre-
REPORT ON OCEANOGRAPHY 13
war survey of the Discovery Committee. “The properties of the water
and the plankton were observed. It appears that there may be a source
of deep, very saline water in the Tasman Sea moving eastward, counter
to the circumpolar drift.
In 1950, H.M.S. Challenger made an extended cruise across the
Pacific Ocean. Echo soundings, temperatures, and water samples were
taken to 3500 meters depth. The bottom morphology and submarine
geology were studied by samplers and seismic methods. Magnetic obser-
vations, plankton hauls and bird observations were also made.
HAWAII
The Department of Zoology in the University of Hawaii maintains
a biological station from which studies of the surrounding seas are con-
ducted. These are particularly concerned with the occurrences and
catching of white bait. Recent researches have shown that tuna are
attracted and induced to school by certain extracts of tuna and other
fish. [his is a major discovery which may well revolutionize the fishing
techniques.
HONGKONG
A Fisheries Research Unit has been set up within the precincts of
the University of Hongkong. Financed from Colonial Development and
Welfare Research funds, the Unit is housed in the Northeast Science
Building. Such also contains the Departments of Biology and Physics.
The Fisheries Research Unit is staffed by a Director, a Chief Scien-
tific Officer, and three Assistant Scientific Officers. A steel-hulled modi-
fied timber on the diesel power is under construction as a research ves-
sel and will be launched under the name of “Alister Hardy” on 27 No-
vember 1953.
The research programme of the Unit is in course of formulation,
and researches on (i) the biology of three of the most important com-
mercial species of fish, (ii) the biology and pond cultivation of grey
mullet, (iii) the methods and organization of freshwater fish culture,
and (iv) the occurrence and distribution of freshwater and reservoir
algae have been initiated. These will be supplemented by a preliminary
oceanographic programme as soon as the research vessel has been com-
mended.
INDIA
While not one of the Pacific nations, oceanographic investigations
in India will be of importance in the immediate future because of the
Indo-Pacific Fisheries Council. Until recently, very little attention has
been given to oceanographic investigations. The Government of India
14 EIGHTH PACIFIC SCIENCE CONGRESS
constituted the Central Board of Geophysics early in 1949, and a special
committee on oceanography functions under this board. Oceanographic
studies have been initiated in the Central Marine Fisheries Research
Station and by the Indian Meteorological Department. Investigations
of the latter deal particularly with turbulence and microseismic waves.
Continuous tidal stations are maintained by the Indian Survey. The In-
dian Navy has conducted researches on underwater sound and the ver-
tical thermal structure of the sea.
The teaching of oceanography is carried on at Andhra University
where physical oceanography is given in the Geophysics Department,
marine geology and marine zoology in the respective Departments of
Geology and Zoology.
INDONESIA
In 1948 an oceanographer, Mr. C. Ph. Veen, was attached to the
Laboratory for Investigation of the Sea at Djakarta. As there were no
sufficient instruments available at that time and as there was no vessel
available, only surface salinities were taken into consideration.
This was done with the help of lighthouses, taking daily samples,
and with the help of merchant ships. These merchant vessels take a
sample of sea water every month, wherever they may be. Gradually this
service grew and nowadays there are about 125 ships concerned in the
work, bringing in 42000 samples of water yearly to the Laboratory. “Iwo
Dutch and one Danish shipping companies are involved.
In the beginning only Indonesia waters were considered but later
it became clear that for a thorough understanding of what was happen-
ing with the currents during the different monsoons, an extension proved
to be unavoidable. So nowadays samples are collected even in the Indian
Ocean to the South and West of Indonesia and beyond the Torres Strait
in the East and to the northwest in the China Sea up to Formosa.
Out of all the data collected, monthly charts of salinities were
mapped and three monthly means were drawn up for the full West and
East Monsoon and for the times between.
This was published up to 1951 in the periodical OSR NEWS and a
second publication was made wherein all data of Schott, the Snellius
and other sources were taken into consideration. ‘This too was published
in the OSR NEWS.
In 1952 a research vessel, the “Samudra,” was put into commission,
given to Indonesia by the FOA administration of the United States,
meant chiefly for the use of fisheries exploration but fully equipped for
oceanographic research. _ It is too early now to give results.
The biologist devoted some time to the work of the Indo-Pacific
Fisheries Council, an international council sponsored by the FAO. Most
REPORT ON OCEANOGRAPHY 15
of the time was devoted to teaching and to training young Indonesians
out of college, who wished to become assistant marine biologists. ‘The
result proved to be heartening.
JAPAN
This island nation with its dense population is actually dependent
upon the sea for its existence. It is not surprising, therefore, that the
science of oceanography has received more encouragement to develop
here than in any other country of the Pacific area. Courses are offered
in the various phases of oceanography in many universities and much
fundamental, basic research has been conducted by professors in these
institutions.
Japan has approached oceanography from the standpoint of fish-
eries, meteorology, and hydrography, and all investigations and observa-
tions have been coordinated by a Marine Research Council. All fish-
erjes resources are receiving intensive study. The Meteorological Ser-
vice makes numerous daily records of the sea water temperatures. The
Hydrographic Office and Maritime Safety Agency is concerned with the
charting of the seas and coasts, the tides, tidal currents, and tsunamis.
The considerable resources of each agency are available to the others
through the coordination council.
There are eight Fisheries Research Institutions, the Hydrographic
office, and five principal Meteorological observatories, and at least ten
research ships. Each department has a series of journals which provide
for publication of data, researches, and studies.
In addition to these observing and applied research groups, the
theoretical aspects are studied in the Geographical Institute, and in se-
veral universities. “The Oceanographical Society of Japan provides a
meeting place for the scientists and publishes a technical quarterly jour-
nal. |
Japanese oceanographers are studying the behaviour of the north
flowing warm Kuroshio and the south flowing cold Oyashio, which are
the dominant currents among the ocean currents. The advance of the
Kuroshio in the summer, its retreat in winter, and its meandering are
complementary to the Oyashio’s.
A similar balance of currents occurs in the Sea of Japan, but with
different emphasis on the cold and warm water masses. This cold
water on the Pacific side may be invaded by warm water through Tsugaru
Straits. These circulations are dominated by seasons and winds, and
the coastal regions are modified by tides. Oceanographers are describing
the character and behaviour of these water masses, which are of major
concern to the fisheries and climate of Japan.
16 EIGHTH PACIFIC SCIENCE CONGRESS
In coastal waters the tides, tidal currents, waves and tsunamis are
being studied so that they may be forecast for the safety of vessels and
coastal populations. ‘The physical and chemical properties of the waters
and their fluctuation with season, weather, and state of the sea, are
important to fisheries and are being studied in all areas. The total of
this work is enormous.
The Japanese have given much attention to the development of
methods, equipment, and material for oceanographic research. Standard
sea water comparable to Copenhagen water is being produced. Revers-
ing thermometers are being manufactured, and many new instruments.
have been designed such as recording current meters, wave recorders and
computers, bathythermographs, and a bathysphere.
MALAYA
Le Mare and Tham, in Malaya, have made a statistical analysis of
the relation of physical and chemical factors with the quantity of trap-
caught fish. ‘They considered wind, rainfall, temperature, salinity phos-
phate and plankton pigment in relation to the catch of anchovy, sprat,
dorab and Spanish mackerel in the Singapore Straits, and solved a re-
gression equation for the independent variables. With this they pre-
dicted the monthly catch through 1948 and 1949 within twenty percent.
Admittedly their situation is particularly suited to these analyses,
but they are, nevertheless, to be congratulated in solving this direct re-
lation; and their methods may well be extended to similar fisheries else-
where.
This is an instance where one of the ultimate objects of oceanog-
raphy has been accomplished.
NEW CALEDONIA
The Laboratoire Oceanographique de I’Institut Francais Oceani-
que (The Oceanographic Laboratory of the French Ocean Institute) is
undertaking a large fisheries research program, with financial aid of the
South Pacific Commission.
The Muséum National d’Histoire Naturelle of Paris has sent Pro-
fessor Ranson to Tahiti to study the production of pearls and shell, and
to determine the best methods of exploitation. He has introduced mo-
dern methods of oyster culture with encouraging results.
NEW ZEALAND
Prior to the 7th Pacific Science Congress, there was little organized
oceanographic research, although a number of individuals were actively
engaged in various studies. Recently an intensive hydrographic sur-
vey program, which also includes regular observations of waves and of
REPORT ON OCEANOGRAPHY 17
the properties of coastal waters, was undertaken. In 1950 the New Zea-
land National Committee on Oceanography was formed as an advisory
body to the Council of Scientific and Industrial Research. It has oper-
ated in effecting liaison, sponsoring research projects and in advising
the New Zealand government on oceanographic matters. In the field of
physical oceanography, arrangements were made for the preparation of
a bathymetric chart of adjacent seas, for the collection of continuous
echo sounding profiles, particularly on voyages between New Zealand
and Australia and outlying islands. Cooperation was given to several
extensive expeditions working in the Antarctic and South Pacific areas.
Many programs in oceanic biology have been inaugurated by several of
the universities.
PACIFIC OCEAN FISHERIES INVESTIGATION
An extensive series of investigations is in progress dealing with
the physical, chemical, and biological properties of waters of the Cen-
tral Equatorial Pacific along with experimental fisheries operations.
This is an effort to evaluate the situations in which fish, particularly
tuna, are present or absent. They have described the water structure of
the north and south equatorial currents, and the counter-currents be-
tween them; have found a subsurface counter-current and a mid-ocean
region of upwelling with high phosphates and much plankton. On
the basis of these encouraging reports their work is being intensified.
Much data has been collected in Hawaiian waters but has not yet been
analyzed.
PHILIPPINES
From 1947 to 1950 oceanographic investigations were made in the
Sulu and Celebes Seas by the Fish and Wildlife Service of the United
States under the Philippine Fishery Program. During that period 526
hydrographic stations were occupied. Observations made at each station
included temperature, salinity, dissolved oxygen, phosphate, nitrate, hy-
drogen ion, and silicate. The observations extended generally to a depth
of 2000 meters and in some cases to a depth of 4000 meters.
The waters surveyed included the Celebes Sea, the Sulu Sea, all of
the smaller seas of the Philippines, the nearby waters of the South China
Sea, and the waters of the Pacific east of the Philippines to a distance
of about 300 miles from shore. Most of the areas were surveyed twice;
once during the northeast mensoon and once during the southwest mon-
soon.
Following the termination of this operation in June, 1950, the U.S.
Agency turned over a small ship and some oceanographic gear to the
Bureau of Fisheries of the Philippines.
18 EIGHTH PACIFIC SCIENCE CONGRESS
Monthly surveys of selected areas have been made throughout a
year or more to determine the cycles of oceanographic conditions and
their relation to wind, weather, and season. Daily observations of sea
water temperature and salinity are made at three shore stations. Water
and air temperatures are collected by ocean shipping.
SOUTH AMERICA
For the vast oceanic areas in the eastern Pacific, off the coasts of
South and Central America, organized programs of research have been
exceedingly limited. However, in the past several years the Food and
Agriculture Organization of the United Nations has done much to ini-
tiate and stimulate investigations in oceanography and particularly in
fisheries.
The first part of an atlas of the coastal current of Peru and a series
of monthly maps of the Peruvian littoral with indications of the average
sea-surface temperature, air temperature, barometric pressure, wind direc-
tion and force for the years 1946 to 1951, have just been published. The
Guano Company has installed a central department of oceanography and
ichthyology in their main office in Lima, from which three biological
stations are administered. One station deals with the behaviour of
oceanic birds, another is concerned primarily with plankton studies and
the third with the biology of the anchovy. The Peruvian Navy as well
as the Guano Company has cooperated with recent oceanographic expe-
ditions in the eastern Pacific operated by the Scripps Institution of
Oceanography and by Yale University. Educational work in Oceanog-
raphy is just beginning. The Geographic Institute of the University
of San Marcos recently gave a series of lectures on oceanography. The
attendance in these lectures has been primarily graduates of the univer-
sity who are teachers in the Peruvian public schools.
Pure oceanographic research has not been conducted to any extent
by Chilean investigators, the tendency being to study the sea as the
habitat of organisms of commercial value. However, considerable basic
data have been collected by the Chilean Navy and by merchant ships.
Two biological stations, one operated by the University of Chile at
Montemar and the other by the University of Concepcion in south cen-
tral Chile, give promise of undertaking oceanographic research in the
immediate future, due to the activities of representatives of the Food
and Agriculture Organization and the Chilean Navy.
The Food and Agriculture Organization and the Centre of Scientific
Cooperation of UNESCO for Latin America are studying ways and means
of organizing an international network of marine laboratories in Latin
America. Laboratories on the Pacific coast will stress investigations of
REPORT ON OCEANOGRAPHY 19
the Humboldt and El Nino Currents. The cold Humboidt Current as
well as the warm countercurrent of El Nino has a strong effect in the
distribution of fishery resources as well as the climate of western South
America. A regional fisheries council is being organized for South Amer-
ica, and attention is being given to the establishment of centers for the
training of personnel to engage in fisheries and oceanographic investi-
gations.
THAILAND
Oceanographic work is just beginning. Tidal observations are
being made, sea water temperatures and salinities are being observed,
and a fisheries research laboratory is being established. Trained per-
sonnel are required to lead this work.
The Hydrographic Service of the Navy has a division of oceanog-
raphy which is mainly concerned with the preparation of Annual pre-
diction of tides and tidal currents in the Gulf of Thailand.
Some salinity data has been collected near the mouth of the river
at irregular intervals during the past two years.
The Department of Fisheries established a Marine Station at Bai
Be Rayong in 1953. ‘The program has not yet been established.
It is hoped that the Hydrographic Service and the Department of
Fisheries will co-operate in the collection of temperature and salinity
data in the Gulf of Thailand, especially in the areas of the river mouths.
UNITED STATES OF AMERICA
Programs in oceanography are carried out more or less independent-
ly by services of the federal government, by organizations or bureaus of
the several states, and by some universities.
The U. S. Coast and Geodetic Survey is occupied primarily with
the charting of coastal areas, tidal studies, and investigations of tidal
and nontidal currents. The Fish and Wildlife Service is concerned
with oceanography in relation to fisheries and have conducted a large
number of investigations in Alaska, Hawaii, the Trust Territories of
the Pacific and off the Pacific coast of the United States. Numerous
projects of the U. S. Navy are in progress and much fundamental re-
search is sponsored by the Office of Naval Research through grants
to universities. Planning of oceanographic studies is made by the
Hydrographic Office of the U. S. Navy and this organization serves as
a general clearing house for much oceanographic information. The
U. S. Coast Guard has cooperated in furthering various studies. ‘The
National Academy of Science and the National Research Council have
done much to stimulate oceanography in the United States.
20 EIGHTH PACIFIC SCIENCE CONGRESS
Two international commissions, the International Halibut Com-
mission and the International Salmon Commission, both established by
treaty between the United States and Canada effectively operate in the
conservation and studies of these two fisheries.
The U. S. Fish and Wildlife Service, the California Academy of
Sciences, Hopkins Marine Station of Stanford University, the California
Fish and Game Commission, and the Scripps Institution of Oceanogra-
phy of the University of California, have sponsored the Marine Research
Committee. Working with three ships and a large staff this project
has observed the currents, the properties of the water, and the marine
organisms within a limit of 300 miles off the California coast in connec-
tion with studies dealing with the life history and habits of the Cali-
fornia sardine. These investigations have also contributed materially
to the blue fin tuna. it
The Scripps Institution of Oceanography, located at La Jolla, a
part of the University of California, offers a series of graduate courses
in practically all of the branches of oceanography. ‘This institution,
since the last Congress, has conducted several extensive exploratory expe-
ditions over much of the Pacific area.
In California attention has been given to coastal wind phenomenon,
the nature and extent of upwelling, studies of waves, beach erosion,
submarine canyons, sea mounts and the various oceanic fisheries.
The University of Washington with its laboratories in Seattle and
at Friday Harbor now offers undergraduate training in oceanography
in addition to extensive graduate work. ‘The research activities are
primarily concerned with the oceanography of the coastal waters of the
State of Washington, and the oceanography of numerous straits, sounds
and estuaries. ‘There is considerable cooperation between the Depart-
ment of Oceanography and the School of Fisheries.
Because of the great industrial development and increasing popula-
tion, the United States is faced with problems arising from the pollu-
tion of coastal waters. Methods of predicting pollution and of utilizing
local sea currents to effectively remove such pollution have been devised.
In general, the United States is examining all phases of oceanog-
raphy in their own coastal waters with particular emphasis on the
mechanisms of currents, and waves and their variation with season and
weather, as well as their relation to fisheries. Detailed studies of the
bottom topography, submarine geology, properties of the water, and
general oceanographic processes have been conducted. In addition,
many transocean expeditions have been and are being made to all parts
of the world to increase the knowledge of structure, properties of the
water, currents, depths, bottom material and marine organisms.
REPORT ON OCEANOGRAPHY 21
The results of all of this work are available in special publications
from the various institutions, State and Federal publications, and the
journals of the learned societies.
A series of investigations on fish poisoning and poisonous fishes of
the tropical Pacific have been in progress at the School of Tropical
Medicine at Loma Linda, California. These studies emphasize the
necessity of toxic fishes and the nature of ichthyosarcotoxins. Lack
of such knowledge tends to hamper the economic development of the
shore fisheries of the tropical Pacific.
VIET-NAM
The 1949-53 period has been marked by a slowing of activities as
related to the constitutional modification arising from the transfer. of
the Institute to Viet-Nam, and with the strife in the Territory.
An increase in activities started in 1952-53, and a more marked
increase is expected in 1954. ‘The Institute presently has two labora-
tory chiefs. There will be four in 1954. “Temporary foreign researchers
are also requested for the laboratory.
The work presented during the period was more particularly di-
rected toward the investigation of the flora and fauna of Viet-Nam.
A science Museum for this fauna containing actually 30,000 specimens
or 3,000 species has been established. Study of the fisheries has also
been overtaken, most particularly in the field of the technical knowl-
edge of fishing gear at Viet-Nam.
The results of the work have been the subject of more than 20 pub-
lications of varying importance, appearing either in the publications of
the Oceanographic Institute of Nhatrang or in foreign publications.
WESTERN SAMOA
The observatory of Apia is under the control of the Department
of Industrial and Scientific Research, New Zealand. Investigations are
undertaken in meteorology, terrestrial magnetism, seismology, and in
more general fields such as tidal predictions. As far as oceanography
is concerned the Observatory records the heights and times of tides and
the daily sea temperature and density. ‘These results are forwarded to
the U. S. Coast and Geodetic Survey. ‘The Observatory is also under-
taking some experimental work on a solar still for the New Zealand
Reparation Estates in Samoa.
eo eee ee ow
22 EIGHTH PACIFIC SCIENCE CONGRESS
PART III
REPORTS ON ACTIVITIES OF SPECIFIC COUNTRIES ON
RESEARCH ORGANIZATIONS
OCEANOGRAPHIC RESEARCH IN AUSTRALIA SINCE 1949
By H. ‘THOMPSON
1. Research Programmes in Progress
In each of the Australian Universities small research projects on
marine animals are being undertaken by post graduate students in the
various Departments of Zoology. “These are not to be regarded as por-
tions of an integrated programme of oceanographical research. Each of
the six state Departments of Fisheries is concerned mainly with the ad-
ministration of Fisheries Acts, but each undertakes some biological re-
search on particular fisheries problems.
The Division of Fisheries of Commonwealth Scientific and Indus-
trial Research Organization at its headquarters, the Marine Biological
Laboratory, Cronulla and at five field stations in various parts of Aus-
tralia carries out a research programme in the following sections: (1)
Oceanography including Hydrology and Planktology, (2) Biology in-
cluding studies of fish, crustacea, shellfish, and whales, (3) Microbiology,
(4) Underwater fouling of ships and structures.
2. Division of Fisheries, C.S.I.R.O. P. O. Box 21, Cronulla, N.S.W.
3. No institution gives specific training in oceanography though the
Department of Zoology of each University gives lectures on marine or-
ganisms and ecology.
4. Australia as a member government of United Nations F.A.O. has
maintained a close link with the Indo-Pacific Fisheries Council. Repre-
sentatives have been sent to each of the meetings of the Council and at
the 3rd and 4th meetings the Australian delegate was Chairman of Tech-
nical Committee I.
5. Summary of research results of C.S.I.R.O. Division of Fisheries.
i) Oceanography
Oceanic studies. F. R. V. “Warren” has carried out a number of
oceanographical cruises in S.W. Australian waters. S°/,, O,, Inorganic
P, Organic P, and Nitrate N. The results of these surveys are given in
volume 3 of Oceanographical Station Lists.
REPORT ON OCEANOGRAPHY 23
R. R. V. “Discovery II” in 1950-51 worked 300-mile section lines, are
off Sydney, Eden, Pt. Culver, Albany, and Rottnest Island. The data
are not yet published but certain results are given in a paper entitled
“A Comparison of the Hydrological conditions off the Eastern and West-
ern coasts of Australia.” (I.P.F.C. Section II Proc. Madras meeting.)
Through the courtesy of her owners, the T.S.M.V. “Wanganella”
is now collecting surface salinity and temperature observations on her
regular fortnightly cruises from Sydney to New Zealand.
The salinity temperature characteristics of the surface Tasman Sea
water masses have now been determined and their seasonal variation in
position, particularly as they affect coastal waters, will be followed in
the future.
il) Coastal Studies
The monthly sampling at various coastal stations in Eastern and
Western Australia has been continued. ) 43=27) blew also seni
died the optical significance of the transparency measured by Secchi’s
disc. He concludes that the transparency of sea water should be defined
as the depth at which we cannot distinguish the difference in colors of
the disc with the surrounding water, in addition to the difference of il-
lumination (OM, 4, 1950, 129-136). He also pointed out that the ex-
tinction coefficient is a constant peculiar to sea water, independent of
the altitude of the sun and amount of clouds. He determined the re-
lation between extinction coefficient and wave length of light and ob-
tained a standard value of extinction coefficient for each of Forel’s
scales of color of the sea. He divided the extinction coefficient of sea
water into the absorption and scattering coefficients. According to his
observations with a photometer of photoronic cell type, scattering coef-
ficient occupies only 10% of the extinction coefficient. This fact re-
quested him to assume the existence of a colored substance in sea water.
He determined the relation of transparency and extinction coefficient
and showed that the formula at Atkins and Poole only holds for small
value of transparency. This conclusion agrees with observations very
closely (KJ, 4, 1952, 268-324). K. Hishida also made a photometer
of the photoronic type and found that the submarine illumination has
much to do with the hydrography (MMOR, 2, 1951, 21).
A theory of transparency of sea water was propounded also by T.
Nan’niti, who derived a theoretical relation between transparency and
hydrographic factors (MGP, 3, 1953, 195-201).
Annual variation and correlation between color of the sea, trans-
parency and the plankton volume were studied by M. Koizumi. He
found that there are two maxima in the color and transparency of the
sea, that is, in summer and winter and two minima in spring and fall,
and that this variation reflects the seasonal change of plankton volume
which reaches a maximum in spring and a secondary maximum in the
fall. From this result a simple formula was obtained between them
(JOSJ, 8, 1952, 79-83).
Sea Ice
The intense studies on the sea ice in the areas around Hokkaido,
the northernmost island of Japan, have been made by K. Fukutomi
and his colleagues, K. Kusunoki, T. Tabata, T. Kashima, M. Saito, U.
Kudo, and others. They are published in the Japanese language in 18
papers entitled “Studies on Sea Ice” during the period 1949-52 (TK,
3-9, 1950-52). Kusunoki compiled a bibliography of Sea Ice in Japan
and made a list of references dated from 1892 to 1950 (JSSI, 13, 1952).
REPORT ON OCEANOGRAPHY 51
Fukutomi made extensive studies on the formation and growth of
the ice crystals in sea ice, salinity and physical measurement of strength,
microscopic inspection of the structure of sea ice, prediction and the
growth of ice in the central part of the Okhotsk Sea. He also found
that there is a turbulent layer of about 40 m. thick on the surface of the
Okhotsk Sea. He established a theory of formation and growth of sea
ice and applied it to this area and could predict when the ice is formed
in this area, and how it grows. He also tried to estimate by simple
empirical formulas the dates at which the air temperature over the
sea reaches the freezing point of sea water. He made an extensive
survey of ice along the north coasts of Hokkaido Island and discussed
how the temperature distribution varies with the cycle of the atmo-
spheric temperature, and compared the result with theory. He mea-
sured the temperature and salinity im situ, and concluded that off the
northern coast of Hokkaido there exists a supercooling in the sea wa-
ter just below the lower surface of the ice. Fukutomi, Kusunoki, and
Tabata examined the wind drift of ice and recognized the influence
of the Earth’s rotation showing a deviation from the direction of the
wind. They made experiments with a floating block of ice in a narrow
sea and applied the result on the ice drift off the northern coast of
Hokkaido. ‘They also discussed theoretically how the stationary motion
of ice occurs when the surface of the sea is partially covered and com-
pared the result with those obtained by Nansen in the Arctic Sea dur-
ing the drift of the “Fram” in 1893-96. Fukutomi and Kusunoki also
published a theory on the formation and structure of ice ridges. Fuku-
tomi, Saito and Kudo measured various physical properties and struc-
ture of the sea ice by photographic methods. Fukutomi gave a theory
for the approximate estimates of the thickness of sea ice in relation to
the average air temperature, and its annual range. Tabata tried a pre-
diction of the data at which a last tract of drift-ice can be seen in
the southern Okhotsk Sea coast of Hokkaido (TK, 3-9, 1950).
Hydrography
The hydrography of the East China Sea was discussed by M. Uda
and he made clear the seasonal variation of water temperature, salinity
and meteorological factors in the Yellow Sea and the East China Sea,
and showed that the fluctuation of the Kuroshio at the margin of the
continental shelf controls the intensity of the Tsushima Current. (Re-
port of the Seikaiku Regional Fisheries Laboratory, 1950). He also dis-
cussed the hydrographic fluctuations in the Japan Sea (Japan Sea Re-
gional Fisheries Laboratory Report, 1952).
Hydrography in the Japan Sea during the spring and summer,
1949, has been reported by I. Yamanaka (JOSJ, 6, 1951; 1953, in press).
52 EIGHTH PACIFIC SCIENCE CONGRESS
Hydrography of the northwestern part of Hokkaido in 1949 was
reported by K. Fukutomi and others (A Survey of Deep Sea Fish in
Northern Part of Japan Sea, 1950), of the region south of the Kurile
Islands and the southern part of Okhotsk Sea, by T. Tabata (TK, 10,
1952), of the northern and middle Okhotsk Sea in summer, 1942, by
K. Kajiura (JOSJ, 5, 1949, 19-27), of the area off the Tohoku district by
J. Fukuoka and T. Yusa (OM, AOS Ze D1):
Of the Kuroshio Current, we have several important works. T.
Ichiye discussed the hydrography in the Kuroshio area in February and
May, giving a theoretical explanation on the meander of this current,
the abnormal pattern off Shionomisaki by making use of jet stream
theory. He also made use of Rossby’s theory of momentum concentra-
tion in concluding that the great cold water mass off the Shionomisaki
consists of the water upwelled from deeper layers (KH, 2, 1951). He
and K. Tanioka also determined the distribution of chemical elements
on isentropic surfaces and discussed the effect of horizontal Austausch
at different points in the stream axis on TS-curves (PRO, 1950).
The Central Meteorological Observatory, Tokyo, has carried out
hydrographic observations regularly in Sagami Bay in 1951 and 1952
and at the weather station (39°N, 153°E) and others (M. Koizumi,
KH, 1, 1950; Koizumi and J. Masuzawa, KH, 2, 1952; Koizumi and O.
Asaoka, KH, 1, 1950; Koizumi, KH, 2, 1952, T. Nan’niti, OM, 3, 1951,
27-48; M. Hanzawa, OM, 4, 1952; ROWJ, 1, 1953).
Hydrographic observations were also carried out on the Antarctic
whaling grounds in the winter months 1950-51 by a fleet of Japanese
whalers. About 30 stations were occupied and the results analyzed (M.
Hanzawa, K. Kobayashi, K. Yoshida, and R. Marumo, OM, 3, 1951).
Hydrography of the two straits of Isaka-wan, the Akashi-seto and
Yuraseto, after heavy rain accompanying typhoon, was discussed by T.
Ichiye (PRO, 1949), Ariake Sea and the inland sea in western Kyushu, by
Nagasaki Marine Observatory in the summers of 1951 and 1952 to make
clear the Kuroshio and the Tsushima Currents in this region. Hydro-
graphic structure in the Tsushima Current area was discussed by T.
Tsujita with special reference to its fisheries importance. (Report of
the Committee on the Hydrographic Investigations in the Western Part
of the Japan Sea, 1952). T. Shinomura and M. Koizumi discussed the
hydrography along the section from Tori-Sima (Bonin Group) to off
Sanriku District (KH, 2, 1950, 55-74).
The hydrography of the Kumihama Bay, a small inlet facing the
Japan Sea, was discussed by K. Hishida (OM, 2, 1950, 67).
The annual variation of sea water temperature in Kii Suido was
discussed in detail by T. Ichiye. He showed the possibility of the fore-
REPORT ON OCEANOGRAPHY da
casting hydrographic conditions in this area (KH, 2, 1951). M. Nagai
discussed the annual variation of sea water temperature and salinity
and made several detailed statistical analysis and stressed that their
fluctuations due to advocation are very important in forecasting these
elements (KJ, 4, 1953).
In 1950 T. Ichiye treated the meandering pattern in the isotherms
observed on the surface along the polar front as the horizontal inter-
nal waves formed along the boundaries between warm and cold water.
(US, 28, 1950).
M. Uda also discussed the characteristic feature of the yearly va-
riation of coastal water temperature and pointed out the advance and
lag of the seasons peculiar to each year. His conclusion was that it is
most important to carry out the hydrographic observations during the
winter months as frequently as possible (US, 30, 1952, 5-7). A survey
of the fisheries in relation to hydrographic fluctuation was also dis-
cussed by Uda in 1952 (TUFY, 38, 1952, 363-389).
Classification of the types of the annual variations of water tem-
perature was made by T. Ichiye. He mentioned three types: seas or
lakes, bay in which tidal currents are strong, and open sea, with several
important discussions (KMOM, 10, 1952).
M. Hanzawa mentions some examples of an abrupt change in hy-
drographic conditions from his experiences in the observations on board
the weather ships. He points out that the advection due to wind effect
is responsible for these changes (OM, 4, 1952).
J. Masuzawa gives some examples showing that a typhoon some-
times acts as a motive for the hydrographic changes in the area close to
their tracks (KH, 1, 1950, 118-123).
Method of forecasting the hydrographic conditions off Sanriku
coast based on the isentropic analysis, was reported by Fukuoka (KH,
950; 30):
Forecasting sea surface temperature in the southwestern part of
the Japan Sea was attempted by K. Hishida (KH, 2, 1951).
The relation between the coastal and offshore water temperature
and other hydrographic elements was analyzed by K. Hishida (MMOR,
Zoot OM, 2; 1950).
Ocean Currents
In 1950, J. Fukuoka made an analysis of the Oyashio Current flow-
ing south in the area to the NE of Japan. He analyzed the TS-curves
from various stations in the Okhotsk Sea and western North Pacific
Ocean, and noticed that the Oyashio water and Kuroshio water can be
found in some latitudes close together, their boundary always oscillat-
54 EIGHTH PACIFIC SCIENCE CONGRESS
ing northward and southward. From this motion he could determine
the velocity of the Oyashio Current (KH, 1, 1950, 10). He also made
another attempt to compare the TS-curves of the sea water at various
stations and could determine the effect of winds in producing the drift
current stations, and could determine the effect of winds in producing
drift current (OM, 1951, 97). He also determined the extent of the
Oyashio Under Current, which is recognized below the warm water of
the Kuroshio (JOSJ, 6, 1951, 202). TI. Nan’niti made an attempt to
know the year-to-year variation of the Kuroshio and the Oyashio. He
says that the Kuroshio was stronger in 1948 and warmer in 1949, and
both of these currents were stronger in the period from the spring to the
early summer of 1950 (MGP, 2, 1951, 102-111). He also made an at-
tempt to compare the curl of wind stress to the intensity of the Kuro-
shio. These two quantity must be proportional according to the Mod-
ern theories of the drift currents (JOSJ, 8, 1952, 23-29).
A very intensive survey of the flowing patterns of the Kuroshio
was reported by M. Uda. He describes the fluctuation of the main axis
of the Kuroshio and its margins. ‘The maximum speed and the width
of the currents were determined based on the dynamic computations
carried out during the period 1934 through 1943. He also explains the
abnormal phase of the Kuroshio flowing in a loop to the south of Japan
as the effect of the monsoon which was very strong in the winter of
1934-35 in addition to the strengthening of the intermediate water
formed as the extension of the Oyashio after it dives below the warm
water of the Kuroshio. He also explains the occurrence, development
of this abnormal phase of the Kuroshio and its recovery to normal
phase, use being made of the past materials (JOSJ, 8, 1951, 181-189).
He discussed the variation of the currents in the Japan Sea, Yellow Sea,
and East China Sea and showed that the Tsushima Current begins at
the 200 m isobath along the margin of the continental shelf of the cir-
culation in the East China Sea (ROWJ, 1, 28-35). Recently Uda de-
scribed the result of oceanographic observations in the adjacent seas of
Hachijo Island in relation to the fisheries (ROWJ, 1, 1953).
Currents in the Japan Sea in the spring and summer, 1949, was de-
scribed by I. Yamanka, stress being especially laid on the meander of
the Tsushima Current which is a branch of the Kuroshio entering this
area (JOSJ, 3, 1951, 143). K. Kusunoki described the speed of the
currents in the Japan Sea close to the west coast of Hokkaido, northern-
most island, and discussed its yearly variation, its periodic cycles and
its relation to the fisheries and ice in the Okhotsk Sea (JOSJ, 6, 1951,
133-142).
REPORT ON OCEANOGRAPHY 55
As to the possible origin of the Oyashio we have the discussion of
N. Watanabe, who found that the most part of the Oyashio originates
in the water of the Okhotsk Sea and very little amount of the Bering
water is considered to take part in the origin of this cold current (JOSJ,
7a, NS)
A very intensive water mass analysis of the Oyashio Current was
made by Yukimasa Saito (JIPOCU, 3, 1952, 79-140).
Water Mass Analysis
It is a very important problem in oceanography to separate differ-
ent water masses and to establish the boundaries between them. Still
we have not had yet any reasonable method for them. M. Nagai has
succeeded in classifying into 7 blocks the system of water masses in the
East China Sea stochastically, numbering the 18x 9 water types having
Sallam nyar29 on 29/50) agp 25730959 and mtemperatune l2s 50 lke lO,
- 05 BOSE, (NK, ©, Mella BeSol))y
T. Ichiye used monthly TS-diagram for determining the intensity
of monthly mass exchange between the coastal and ocean waters. He
showed how the ocean water penetrates into the bay due to the dif-
fusion by eddies. He also discussed the general types of the TS-dia-
gram in the transient region between the ocean and coastal water
(KMOM, 10, 1952).
Recently Michio Miyasaki has been considering the use of T-O,-
diagram in addition to TS-diagram. By doing this, he could classify the
so-called deep water in the Japan Sea into a number of water masses.
He could point out the existence of several important water types in
the deep layers of the Japan Sea (HFLB, 7, 1953, 1-65).
The intermediate waters of low salinity in the regions south and
northeast of Japan have been discussed by J. Masuzawa in their rela-
tion to Kuroshio waters. He pointed out the intense turbulence both
in horizontal and vertical directions and determined the horizontal dif-
fusivity at 106-108 c.g.s. on the isentropic surface (t-26.6-26.8), (OM, 2,
W@BOF INGE 2) WS, Balle, Pee).
Y. Miyake considers that the boron in sea water behaves as a very
good indicator for the water masses and recommends the ratio B/Cl as
a useful tool in the water mass analysis (US, 30, 1952, 14-18).
Ykimasa Saito published a very detailed water mass analysis for
the northern seas of Japan, stress being laid on the research on the
Cyashio. He could explain the significance of TS-diagram in exactly
the same way as W. B. Stockman tried in 1947 (JIPOCU, 3, 1952,
79-140). :
56 EIGHTH PACIFIC SCIENCE CONGRESS
Diffusion
In 1949 T. Ichiye treated the Brownian movement of a particle of
water produced by a stochastic extraneous force in a field of Coriolis
forces, and determined the dependence of eddy diffusivity upon the
latitude. He compared this theoretical result with the horizontal dif-
fusivity determined from the distribution of conservative concentrations
in the ocean currents, and showed how the horizontal eddy diffusivity
could be determined from the drift of R.V. “Deutschland” in the Ant-
arctic Ocean (OM, 1, 1949).
In 1950 Ichiye considered a statistical theory of turbulent diffu-
sion, discussing the diffusion from an origin by a process similar to
Brownian motion, and could explain the so-called scale effect postula-
ted by Lewis F. Richardson (KMOM, 8, 1950). He also made some re-
marks on Richardson’s neighbor diffusion equation (OM, 2, 1950). He
applied this theory to the diffusion of water masses in the oceans and
gave a qualitative explanation on the variation of the horizontal Aus-
tausch coefficient in the ocean currents by developing the spectral theo-
ry of turbulence in case where irregular extraneous forces are in action
(OM, 3, 1951). Yasukazu Saito solved the problem of diffusion of sa-
linity in a horizontal current field, both horizontal and vertical mixing
being taken into account (TUFJ, 38, 1952, 182-191).
T. Nan’niti determined the horizontal and vertical eddy diffusi-
vity using Montgomery’s method from the actual distribution of salin-
ity. He obtained horizontal and vertical coefficients to be 107 and 101
respectively (OM, 3, 1951). From the salinity distribution on the core
sheet of the Subarctic Intermediate water near Japan, J. Masuzawa ob-
tained horizontal eddy diffusivity to be 10%-108 c.gs. (KH, 2, 1951-52).
E. Inoue concluded this quantity has a value 10'° c.g.s., a value much
larger than previously known (KS, 28, 1950, 420-424).
In 1950 Ichiye treated the annual variation of the heat contents
at several stations in Osaka Bay as a horizontal diffusion by tidal cur-
rents (KMOM, 8, 1950).
In 1952 Ichiye discussed the relation between the O, minimum
layer and the motionless layer in case where both horizontal and verti-
cal diffusions occur, and showed theoretically how the depth of O, mi-
nimum layer varies as the distance from the source increases when there
is biological dissipation. He determined the schematic distribution of
oxygen in the sea when the processes of dissipation, supply and diffu-
sion are going on simultaneously (US, 29, 1952).
On September 17, 1952, a new submarine volcano was observed
erupting from the Pacific floor south of Japan. ‘This submarine erup-
tion ejected a great deal of pumice stones afloat on the sea surface,
REPORT ON OCEANOGRAPHY 57
expanding by diffusion in all directions. From the distribution of pu-
mice stones, M. Hanzawa derived an approximate value of eddy dif
fusivity to be 4.8 x 10°-4.3 x 107 c.g.s. (OM, 4, 1953).
Theories of Wind-Driven Ocean Circulation
According to the recent theories of the oceanic circulation, the
main source of energy supply to the major current of the ocean is the
semi-permanent wind system over the oceans. During the period 1949-
53, very active research has been done on this subject.
T. Ichiye has long engaged in the dynamical research on ocean-cur-
rents since 1949 (OM, 1, 1949). In 1950 he discussed the wind-driven
currents produced by circular wind system. In this computation he
retained the inertia terms and applied the result to the motion of wa-
ter produced by a typhoon. He showed that an upwelling must occur in
deeper levels (OM, 2, 1950). He also discussed the wind-driven ocean
circulation in an ocean taking into account the effect of horizontal
mixing. His computation is nearly similar to that of Munk (OM, 2,
1950). He also discussed the equation of ocean current involving the
inertia terms and solved it for a zonal flow in an asymptotic expansion.
By this theory he could show the occurrence of a counter current on
the right side of the current looking downstream (KMOM, 8, 1950).
The same year, Masamori Miyazaki computed the coefficients of
horizontal and vertical mixing on both sides of a current of uniform
velocity by Gebelain’s method and obtained the distribution of ve-
locity across the current. He thus concluded that the occurrence of a
counter current can be determined by vertical distribution of current
velocity (OM, 2, 1950, 53-58). The same year, Miyazaki published a
theory of wind-produced zonal current in an ocean completely covering
the earth, taking into account the effect of both horizontal and vertical
mixing. He could prove that the deviation of current system from
wind system decreases, and the subsidence of current with depth in-
creases by the presence of horizontal mixing (KMOM, 8, 1950, 41-43).
He gave an expression for the coefficient of lateral mixing for a station-
ary state and the decaying stage without supply of energy from outside
(OM, 2, 1950, 113-116). :
In 1951 Ichiye published two papers on the variation of oceanic
circulation. In order to explain the double periodicity found by C.
O’D Iselin for the Gulf Strea, he discussed successfully the variation of
oceanic circulation accompanying the periodic variation of zonal wind
system (OM, 3, 1951). He also computed annual variation of the mass
and heat transports in five sections across the Kuroshio and described
the mechanism of these changes to the density currents due to the phase
58 EIGHTH PACIFIC SCIENCE CONGRESS
lags between the temperature cycles of coastal and offshore waters (OM,
Syl oN):
In 1951 Hidaka published the result of a computation of the gen-
eral circulation of the Pacific Ocean. ‘This is a modification of Munk’s
theory, the only differences being the use of spherical coordinates in-
stead of Munk’s rectangular, and the assumption of two types of wind
system—zonal and anticyclonic. He obtained practically the same re-
sult as Munk’s, except a better agreement than Munk’s of total mass
transport with the actual value 65 million tons per second obtained by
Sverdrup from Japanese observations. It must, however, be borne in
mind that the exact value of total mass transport is very hard to deter-
mine, the recent observations by Japanese giving about 20-40 million
tons per second (J. Masuzawa, KH, 2, 1951) according to the seasons of
the year. This value is far smaller than that of Sverdrup and agrees
with Munk’s theoretical result pretty well.
In 1952 Masamori Miyazaki published a new theory of the wind-
driven circulation and could explain the counter-current observed be-
tween the Gulf Stream and the American continent by assuming a zone
of smaller value of the coefficient of lateral eddy viscosity close to the
coast. [his counter-current has been observed from a long time ago
and many authors have failed to explain except Rossby, who could
solve it by taking into account the effect of inertia terms (OM, 4, 1952).
Yasukazu Saito made a very elaborate mathematical analysis on the
theory of ocean currents driven by winds in an isotropic ocean taking
into account the mixing in all directions. He used the velocity itself
for solving the problems (KS, 28, 1950, 25-61; TUFJ, 38, 1951, 87-179).
Recently Hidaka solved a three-dimensional theory of ocean cur-
rents, thus making it possible to discuss the vertical structure of wind-
driven current. The most outstanding conclusion is that the motion
of water is much more intense than is expected in layers far below than
the depth of frictional influence defined by Ekman (in press).
As to the fluctuation of oceanic circulation caused by the wind
fluctuation, Ichiye made an attempt to determine the curl of the wind
stress in each 5° square over the Pacific from actual observations. Fur-
ther he could determine the annual variation of the horizontal mixing
coefficient on the basis of the spectral theory of turbulence, and dis-
cussed the variation of circulation equalitatively (OM, 4, 1952).
In 1952 K. Kajiura used the idea of Sverdrup and Reid in comput-
ing the current velocities in the upper layers of the eastern portion of
the equatorial Pacific on the assumption that the initial forces and the
lateral friction are negligible. He divided the motion into two parts,
that is, the pure drift currents and the relative currents, and showed
REPORT ON OCEANOGRAPHY 59
that the result agrees satisfactorily with the observations near the equa-
tor. In this region the relative current is much stronger than the pure
drift current, while the meridional components of currents are negli-
gibly small compared with the EW-components (JOSJ, 8, 1952, 15-22).
The dependence upon the bottom friction of sea surface slope in-
duced by wind is discussed theoretically by Ichiye. He determined the
vertical structure of drift currents and compared it with actual obser-
vations. He also obtained the drift current when Rossby’s expression
for the vertical mixing coefficient is used (KMOM, 10, 1952).
Recently K. Yoshida treated successfully the problem of circula-
tion in the upper mixed layer in the equatorial region of the North
Pacific Ocean by solving the steady state equations involving terms of
Coriolis forces, pressure gradient, and horizontal as well as vertical mix-
ing (Hoshida, Han-lee Mao, and Paul L. Horro, in press).
The most part of the theories described above is obtained on the
assumption that the inertia terms in the dynamical equations are neg-
ligibly small compared with the remaining terms. ‘The significance of
these terms in dynamical oceanography was discussed by Hidaka and
M. Miyoshi (GN, 2, 1949). A similar discussion was made by Ichiye,
who concluded that these terms cannot be neglected when the curl of
the wind stress is large, and estimated their magnitude (OM, 2, 1950).
The simplification of the theory of the wind-driven ocean current
will be approached by assuming a zonal ocean and a planetary wind
system so that both winds and currents are independent of longitude.
Theories were worked out by Hidaka and his collaborators K. Takano
and M. Tsuchiya (GN, 3, 1950; GM, 23, 1952, 487-495; JMR, in press).
A very important question in dynamical oceanography is how and
in what proportions the energy of wind is imparted to raising waves
and producing currents. This problem was discussed by K. Yoshida
(JOSJ, 7, 1951) and Ichiye (OM, 4, 1952).
In 1952 K. Kajiura discussed on the currents and the accumula-
tion of water produced by winds in the water consisting of two layers
of different densities. He assumed that the eddy viscosity is negligible
along the boundary of two layers and showed that the shape of the
boundary surface agrees very closely with observations (JOSJ, 8, 1952,
67-71).
Upwelling and Coastal Currents
Recently K. Hidaka propounded a hydrodynamical theory of up-
welling. He assumed an infinitely long straight coast and constant
latitude, and discussed the upwelling to be produced as the effect of
wind blowing in a belt of a certain width from the coast. He took the
60 EIGHTH PACIFIC SCIENCE CONGRESS
Coriolis forces and horizontal and vertical mixing into account. For the
values of mixing coefficients generally accepted, the velocity of upwell-
ing was computed at about 80 meters per month for the wind speed
5-6 m/s and the latitude 30°N, thus coinciding closely with observa-
tions and former estimates. He also showed that the most intense up-
welling will occur when the wind makes an angle 21-5° with the coast
line in an offshore direction. ‘The horizontal motion involved in this
circulation can be considered to form a part of the coastal or long-
shore currents much debated recently (Technical Report, Department
of Oceanography, Texas A. & M., 1953).
In 1950 ‘T. Ichiye, discussing the wind-driven currents produced by
a circular wind system, could show that the upwelling must take place
in deeper layers even in an open ocean (OM, 2, 1950).
Yukimasa Saito published a simple method of computing the ver-
tical velocity of water from the displacement of isophonals. ‘This meth-
od will be very useful when the distribution of density is given at a
certain interval of time. He applied his method to the upwelling off
Southern California and obtained the velocity of upwelling 2.55 m/day
or about 80 m/month (JIPOCU, 2, B, 1951, 1-4).
Tides and Tidal Currents
N. Okamoto, Masamori Miyazaki, and H. Yoshizawa succeeded in
obtaining four principal components of tidal currents from fortnightly
observations in June, 1951, by Ono’s recording current meter working
on the No. 2 Buoy in the Osaka Harbor (KH, 2, 1952, 29-34).
Masamori Miyazaki obtained the tidal harmonic constants for Kobe
and Sumoto by the Tidal Institute Method of A. T. Doodson (KH, 2,
LOD 2a 24):
Z. Yasui and S. Ishiguro published an intensive survey and descrip-
tion of the tidal currents in Hirado Channel near Nagasaki. ‘They
made a model experiment at the same time and could explain observed
results very satisfactorily (NMOR, 3, 190). H. Akamatsu made a very
intensive survey of the tidal and nontidal currents around the Goto
Islands to the northwest of Kyushu (KK, 4, 1950, 65-72).
K. Hishida made a survey of currents, tidal or nontidal, close to
the coasts of the Japan Sea and showed that a marked vertical variation
is noticed in them, which may be explained as due to winds and bottom
topography (MCAKU, 62, 1952).
Ichiye reports the observations of tidal currents and waves in Osa-
ka Bay, the Harima Nada, Kii Suido (PRO, 1949; US, 28, 1950; KH,
2, 1951; Report on the Investigations of the Beach Erosion in the south-
eastern part of Osaka Bay, 1).
REPORT ON OCEANOGRAPHY 61
Adventional variation of temperature and salinity due to tidal cur-
rents was discussed by T. Ichiye (OM, 4, 1952). He also treated the
modification of wave form when a long wave propagates through a
channel of varying sections. He applied his theory to the Akashi Seto,
a channel connecting Osaka Bay to another basin situated to the west,
and computed the permeability of the waves when two eave trains meet
in this channel (KMOM, 9, 1951).
A new development in the discussion of the tidal currents in the
Straits of Shimonoseki separating Honshu and Kyushu, two major is-
lands of Japan, was made by Mashito, Nakano. He also pointed out
a comment about its prediction (GJ, 58, 1949, 213-216).
Seiches and Secondary Undulations of Tides
On the occasion of cyclonic storms attacking our islands we fre-
quently notice oscillations of period 1-3 minutes accompanying the
tidal oscillations on mareograms. This phenomenon, now called “surf
beats,” has been long known in Japan. M. Nakano reports a remark-
able series of such undulations which accompanied the storm of 1-5
April 1936, and observed on the mareograms of tidal stations along the
Japanese coasts. Nakano gives a very intensive examination of this phe-
nomenon (OM, 1, 1949, 13-32).
T. Ichiye treated theoretically the oscillations which will be caused
by a sudden impulse of wind exerted on the sea surface and obtained
the relation between the shape of the bay, time variation of the stress
and the amplitude. He pointed out that an impulsive stress is more
effective on producing seiches (JOSJ, 6, 1950).
Sea Level
In 1951 S. Yamaguti showed that the monthly mean sea-level cor-
rected for astronomical, meteorological, and oceanographical effects, can
be fairly used for discussion of the vertical displacement of the earth’s
crust and sometimes may be used in place of precise levelling (GSB, 2,
1950).
Waves
Studies of waves have been made partly in connection with some
practical applications. Forecasting of waves and swells has been needed
for the safety of ships, for protection of coasts and harbors, and in
connection with various problems of coastal engineering. ‘These fore-
casting and practical studies have mainly been carried out by the staff of
the Hydrographic Office, Central Meteorological Observatory, and a
number of branch organizations (M. Nakano, S. Unoki, and K. Yuge,
OM, 5, 1953; H. Arakawa and K. Suda, MWR, 81, 1953; M. Uda, GM,
62 EIGHTH PACIFIC SCIENCE CONGRESS
23, 1952; Yoshida, Kajiura and Hidaka, ROWJ, 1, 1953; K. Sato, HB,
16, 1950; HB, 25, 1951; Miyazaki, KS, 28, 1950; I. Kimura, CKH, 1, 1949;
H. Yamada, FE, 5, 1949; T. Ichiye, KH, 2, 1951; H. Hikada et al., KH,
1, 1949). To locate and track the storm or typhoon over the ocean,
studies of microseisms in relation to the ocean waves have been con-
tinued in the Earthquake Research Institute and in the Central Meteor-
ological Observatory. (F. Kishinoue, ERIB, 29, 1951, 277-282.) Studies
of beach erosion problems have been made with particular activities,
under the cooperation of various research groups. Experimental stu-
dies of surf in a model tank which were made by T. Hamada have
made an important contribution to this field. (Transportation Tech-
nical Research Institute, Report No. 2, 1951, 1-165.)
Theoretical studies of wind waves have been made by K. Yoshida.
He pointed out the importance of the process concerning the mutual
exchange of momentum between ocean waves and ocean currents (K.
Yoshida, JOSJ, 7, 1951, 99-104). He suggested that energy transmitted
from wind to water goes partly into waves and partly into currents,
and furthermore, energy is transferred from shorter waves to longer
waves and also from waves to currents, mainly due to semi-irregular
breaking of waves. Based on a physical consideration, he derived an
equation to find an energy portion required to increase wave height and
wave velocity respectively, and therefrom an equation of wave growth
which slightly differs from Sverdrup-Munk’s (K. Yoshida, GN, 4, 1951).
Energy distribution in wave spectra, which results from his theory of
energy transfer from shorter waves to longer waves, was compared with
actual wave data (K. Yoshida, JOSJ, 7, 1951, 49-54). Based on nonlinear
equations of waves with continuous spectrum, he suggested that the
frequent occurrence of waves of several minutes’ period, surf beats, may
be ascribed to the general structure of the ocean wave spectrum (K.
Yoshida, GN, 3, 1950). Periods of surf beats are estimated approxi-
2
mately from an original spectrum; T = =<. where T denotes a period of
A
energy maximum, and AT is the range of periods of wave components
with a significant amount of energy. M. Nakano published a paper in
1949, Yoshida attempted to find a modification of swell in shallow wa-
ter, where a bottom slope is not gentle enough to allow an ordinary
refraction diagram approximation to be valid (K. Yoshida, GN, 3,
1950). However, available wave records have not been sufficient to
prove and support these theories so far.
An electrical recorder of waves was devised by S. Ishiguro, a very
able hydrographic mechanician. He constructed several types of wave
recorders and an apparatus for the stroboscopic analysis for preparing
the wave spectrum (S. Ishiguro, OM, 1, 1949; KK, 3, 1949; KK, 4,
REPORT ON OCEANOGRAPHY 63
1950; K. Sato, HB, 15, 1949). Wave recorders of pressure type have
been installed at severa! parts of our coasts, and especially continuous
records at Yogashima Island have been analyzed by the staff of the
Oceanographic Section of the Central Meteorological Observatory (M.
Nakano, S. Unoki and Y. Kuge, OM, 5, 1953, in press). The accumu-
lation of such data as well as activities of the staff may afford a pro-
mise of progress in forecasting. One of the most successful and interest-
ing results from the wave recorders installed by this staff is that a re-
corder at Hachijo Island recorded long sea waves (tsunamis) produced
by an eruption of a submarine volcano in September of 1952, and that
S. Unoki and M. Nakano could explain the observed change of period
and district beat phenomena by solving the wave problem of Cauchy-
Poisson type (S. Unoki and M. Nakano, OM, 4, 1952; OM, 5, 1953).
This record at the station 130 km. distant from the volcano showed
that the period decreases gradually with the lapse of time, from 95 sec,
to 30 sec., and also showed distinct beat pattern. A stereophotogram-
metric study of the surface was atempted by K. Sato, who was lost on
board the wrecked vessel at the eruption of the Myojin volcano.
In 1951 and 1952, Masamori Miyazaki published papers on math-
ematical studies of surf and breakers in water of constant slope (Masa-
mori Miyazaki, OM, 3, 1951; OM, 4, 1952). He also discussed the wind
stress over the wavy sea surface mathematically (OM, 3, 1951). A prob-
lem of “tidal race’ was taken up by Miyazaki in 1949 and by T. Ichiye
neo ei(ichive; OM; 1929; Miyazaki, OM, 1, 1949). K. Hidaka
published two papers of surface waves in 1951. He proposed a very
simple explanation as to why the group velocity is equal to the velocity
with which we can follow the waves without change of wavelength
(K. Hidaka, JOSJ, 7, 1951). Hidaka and A. Nakano calculated the sur-
face profile of high waves from Stokes’ equation by means of numeri-
cal calculations instead of successive approximation procedures (Hi-
daka and A. Nakano, JOSJ, 7, 1951).
Storm Tides
Ariake Sea, which is a shallow water in the island studded part in
western Kyushu, has a big productivity. “This area is much frequented
by typhoons. A computation was made by K. Terada as to how high
the storm tides accompanying the passage of typhoons would be. A
theory for such a phenomenon had been established by several persons
immediately after the “Muroto” Typhoon which caused serious dam-
age in the heart of Japan by a heavy storm tide in 1934. Masamori
Miyazaki is one of those who recently solved the problem of storm
tides caused by a travelling storm in an infinite and semi-infinite seas
(OM, 4, 1952, 1-12).
64 EIGHTH PACIFIC SCIENCE CONGRESS
The storm tides caused by a heavy typhoon which attacked Japan
in September, 1950, were also examined by Masamori Miyazaki in 1951.
The storm tide-height amounted to about 125 cm. along the Kyushu
coast facing the Inland Sea.
He also analyzed the data obtained during the passage of the
typhoon “Muroto” (1934) and the typhoon “Jane” (1950), which went
across Osaka Bay, and made some additional explanation of the seiches
with periods 310 minutes and 70 minutes which were observed during
the passage (KH, 2, 1951). The storm tide caused by the typhoon
“Jane” was also discussed by K. Hishida and T. Wakabahashi and was
reported to have amounted to a height of 60-70 cm. (KH, 1, 1950, 185).
A series of dynamical studies was made by S. Unoki during the
period 1950-51 on the effect of atmospheric pressure change on the va-
riation of sea level. He found that the sea level always responds to the
variation of the atmospheric pressure after a lag of time. ‘This lag is
found to increase with the period of the atmospheric pressure variation,
velocity of travelling surface pressure disturbance and the latitude, and
decreases with the depth of the sea. These observed facts were shown
to agree with the theory pretty well (OM, 2, 1950, 1-15). He also made
an attempt to improve the Colding formula for estimating the eleva-
tion of the sea level caused by stationary winds. He studied the effect
of the fetch, variation of depth and the gradient of wind velocity on the
variation of sea level (OM, 3, 1951, 1-16). He further pointed out
that the lag between the wind and the sea level variations is usually
small when only the wind direction varies, but the phase-difference is
large when the wind force varies, being closely related with the lati-
tude, the angle between the wind and coast line, and the rate of varia-
tion of wind velocity. But the most important conclusion he obtained
is that the elevation of sea surface is considerably larger when the wind
direction rotates counter-clockwise than when it does clockwise, even
when the absolute value of wind velocity and the rate of variation of
wind direction remains the same. ‘This means that larger elevation of
the sea surface occurs when a cyclonic storm passes northward across
the west side of a bay, than when it passes through the eastern portion
(OM, 3, 1951, 53-63).
In 1952, K. Kajiura made a study of the currents and the accumu-
lation of water caused by winds in a lake whose water consists of two
layers of different densities. [The computed profile of the boundary
layer agrees with the observation satisfactorily (JOSJ, 8, 1952, 67-71).
A series of remarkable papers was published by H. Yamada on the
effect of a travelling disturbance on the motion of water in an enclosed
or a semi-open sea. After a tedious computation, he could show the
REPORT ON OCEANOGRAPHY 65
detail of water movement accompanying the passage of storm across
these basins (FE, 6, 1950, 22-33).
Tsunamis
The coastal areas of Japan have frequently been attacked by the
storm waves (surges, or Takashio) caused by typhoon and also by tsu-
namis caused by submarine earthquakes. To protect the coastal areas
from damages due to such high waters, a number of studies has been
made on these problems.
A series of theoretical research was published in the years preced-
ing 1950 by R. Takahashi. In 1951, he published a very intensive work
on the amount of energy of tsunami waves arriving per unit length
of segment along the Pacific coasts of the Japanese islands per century.
This research is very useful to anticipate the possible damages by tsu-
nami attacking our islands in future, providing the seismic activities
remain unaltered for the time being (ERIB, 29, 1951, 76-96).
T. Ichiye has published another series of papers on tsunami. In
1949, he made a model experiment of the tsunami waves entering Osaka
Bay from the Pacific Ocean and studied the patterns and characteristics
of the oscillations peculiar to several portions of this bay around which
are located many important industrial and commercial cities in the
heart of Japan. He also attempted to take the effect of viscosity into
consideration (KS, 26, 1949).
Afterward he propounded a theory of tsunami and discussed the re-
flection and penetration of tsunami waves as they pass into the shelf
taking into account the interrelation between the length and period
of tsunami waves and the depth and bottom slope of the shelf, and ob-
tained a correction to Green’s law of change in amplitude. He also suc-
ceeded in computing the reflectivity and permeability of tsunami which
attacked Osaka Bay just mentioned from several directions of the Pa-
cific. He also took into account the effect of viscosity on the shelf
(KS, 27, 1949; OM, 2, 1950). He also established a theory of tsunami
caused by a travelling disturbance on the bottom. ‘This theory of tsu-
nami produced by a moving source is very helpful in treating the ob-
served waves of tsunami. He first computed the tsunami waves when
the submarine dislocation moves in a direction and showed that there
occurs in a train of waves if the velocity of source is smaller than that
of long waves, and a solitary wave is produced when the source moves
faster than the long wave (KMOM, 8, 1950). Next, he treated the
case where a circular elevation or depression is moving on the bottom.
The patterns of oscillations remain the same except that the wave
height decreases as the reciprocal of the square of the distance (KMOM,
Y), US):
66 EIGHTH PACIFIC SCIENCE CONGRESS
It has been a common sense that the tsunami wave becomes highest
at the head of a bay. But, according to the observed data of the San-
riku Tsunami, March 4, 1952, this was proved not to be necessarily the
case. ‘To explain this fact, Ichiye assumed a frictional resistance on the
bottom of the bay head and had the conclusion that the amplitude be-
comes a maximum at the middle portion of the bay (KMOM, 10, 1952).
Although these papers are very excellent, it might be more advis-
able now to have a tsunami recorder and to analyze the records more in
detail. D. Shimozuru and T. Akima found tsunami waves of long
period, about 80 minutes, superposed on shorter period waves of tsu-
namis in the tidal record of December 21, 1946, by means of mechanical
law-pass filter of torsion pendulum type. The investigation of the phase
of the long period waves appears to indicate that they are due to the
reflection from Guam Island (ERIB, 30, 1952, 223-230).
The accounts on the Sanriku Tsunami, March 4, 1952, have been
published by several authorities including the Earthquake Research In-
stitute and Geophysical Institute, Tokyo University, and the Central
Meteorological Observatory, and others. In the Geophysical Institute,
Tokyo University, an expedition was issued for the investigation and
the report on tsunami waves and its patterns was published by K. Yoshi-
da, K. Kajiura, and H. Miyoshi (JOSJ, 8, 1953). An importance of
the reflection of tsunami waves by continental slope was pointed out in
this report. In the case of this tsunami, a warning system was success-
ful. Various problems having been discussed concerning the propaga-
tion of tsunami waves (T. Ichiye, US, 26, 1949; T. Ikano, CKH, 2, 1950;
S. Homma, KS, 28, 1950; T. Rikitake, ERIB, 29, 1951), interesting is
an application of diffraction problem to tsunamis which was made by
K. Hidaka and S. Hikozaka concerning a distribution of wave-height
on the coasts of Kausi Island in the case of the Hawaiian tsunami of
1946 (JO, 5, 1949). Similar discussion was also made by S. Homma
(GM, 21, 1950). Contributions were also made by model experiments
of tsunami which S. Ogiwara, and T. Okita attempted (CKH, 2, 1950;
SRTH, 2, 1950). '
It should also be mentioned that records of the sea shock on Au-
gust 10, 1949, were obtained by S. Takagi, using a seismograph installed
on board an anchored ship (US, 27, 1950). Another important work
is a theoretical discussion of flood waves by S. Yayami, the importance
of lateral mixing being introduced (Disaster Prevention Res. Ins.
Bully 9):
Marine Meteorology
In 1950, Arakawa made a statistical survey of the visibility in the
Northwestern Pacific Ocean using the data observed by the Japanese
REPORT ON OCEANOGRAPHY 67
Navy during the period of ten years beginning September, 1923. He
found that the visibility is excellent in low latitudes almost all the year
round. In high latitudes, poor visibility predominates, especially in
the summer months. In the Far East the Summer Monsoon is directed
from south to north, so the conditions will be favorable for advec-
tion fogs. In the colder half of the year, the obscuring snow in the
rear of winter cyclones on the northern sailing routes reduces visibility
as a rule (MGP, 1, 1950, 58-66). Based on the materials from the
same sources, he and ‘Tsutsumi also discussed the seasonal changes of
daily frequency of squalls in the same area. He concluded that the
frequency of squalls is drastically large in the Equatorial belt east of
Longitude 125°E and south of Latitude 10°N, where the rainfall is
heaviest in the Pacific as mentioned by G. Schott in 1938 (MGP, 1, 1951,
296-301). ;
In 1951, Hokodate Marine Observatory carried out the observations
of fogs around his northernmost island very close the polar front and
confirmed many of former conclusions on this phenomenon, together
with the fact that there are very few of the short period components in
the turbulence when the fog is very dense and the lapse rate of tem-
perature is small close to the sea surface (KJ, 4, 1952, 81-120).
A statistical study was made by M. Hanzawa and T. Inous on the
influence of the variation of sea surface temperature and pressure on
the growth of rice crop (KH, 2, 1952).
Instruments and Methods
In 1950 K. Ono of the Japanese Hydrographic Office, Tokyo, de-
signed an electric shelf recording current meter. This instrument has
undergone several improvements and has been used in several areas
around the Japanese Islands with success. Another design with a photo-
electric cell tube is also published by T. Nan’niti though we have
not heard of its widespread use (MGP, 3, and 4, 1953, 286-294).
In 1950 Nan’niti designed a lazy thermometer and tried a theore-
tical consideration on its time lag.
S. Agari made a design to measure the deep water temperature on —
deck by the use of an electrically controlled distant deep-sea reversing
thermometer. This consisted of a thin carbon thread sealed in a glass
tube. The electric resistance is measured by platinum electrodes at-
tached on this carbon thread. He made tests with both protected and
non-protected reversing thermometers (KJ, 8, 1953).
Shizuo Ishiguro is a very good designer and constructor of oceano-
graphic instruments. He designed a sea wave height recorder taking
advantage of the buoyancy of a cylindrical buoy placed in the water
(KK 19507), 45-09):
68 EIGHTH PACIFIC SCIENCE CONGRESS
He also made an electric recorder for sea wave pressure. The trans-
ducer of pressure gauge is of a variable mutual induction type using
about a 100 cycle/sec. constant audit frequency. ‘The recording appara-
tus consists of six parts: a carrier wave oscillator, a modulator combined
with the pressure gauge, an amplifier and detector, an automatic cali-
brating suit, a direct inking oscillograph and an electrical power supply,
all kept in four portable cases. ‘This apparatus can measure the wave
pressure from 0 up to 50 ton/m? with an accuracy of 2 to 3% in pres-
sure and 1/20 sec. in the period of pressure pulsation. Actual obser-
vations with this instrument proved successful. He made several im-
provements (OM, I, 1949, 135-141; KK, 1, 1948, 2, 1949).
Besides the wave recorder, Ishiguro devised an experimental analy-
sis method for the forced oscillation of water in a lake or sea. The
first method is to take movie pictures of the sea surface illuminated by
a nearly horizontal beam. He also replaced the oscillating water in
a basin by a combination system of electric impedance, the solution
being shown in a cathode oscillograph (KK, 4, 1950, 59-84).
Ishiguro applied the techniques of photogrammetry in order to
measure the progressive phenomena on the sea surface such as tide
waves, and wind waves and swell (KK, 4, 1950, 35-39).
He also devised a drawing instrument or graphic computer to ana-
lyze an irregular wave-form, or to combine different wave patterns, an
optical direction recorder for tidal currents and an electric-contact-type
speed recorder for submarine currents (KK, 4, 1950, 18-20, 21-23). Un-
fortunately these instruments have not yet been constructed because
of his illness.
A nomograph diagram for the temperature correction of a non-
protected reversing thermometer is given by Y. ‘Takenouti and T. Kato
(KEE 1, 1950), 53-56):
The technique of determining the ocean currents by measuring
angle and direction of maximum inclination of the sounding wire was
studied by K. Fukutomi (CKH, 1, 1951). The relation between the
wind and the surface drift was discussed by K. Hishida (JOSJ, 6, 1950).
In 1952 T. Abe made a different model of bathythermograph (KH,
Zr lGb2) 289-296).
An undersea observation chamber ‘“‘Kuroshio” was constructed in
Japan and operated by N. Inoue, T. Sasaki and R. Oaki. ‘This in-
strument, very similar to the bathysphere used by W. Beebe and Otis
Burton in the United States of America was constructed in 1951. This
project is financed by the Yomiuri Shinbun, one of the biggest news-
paper companies in Japan, the Japanese Government, and others. ‘This
was used in the summers of 1951 and 1952 with success. (Journ. Scient.
REPORT ON OCEANOGRAPHY 69
Res. Ins. 46, 1952; ROWYJ, 1, 1953, 52-62; N. Suzuki and K. Kato, Bull.
Fac. Fish. Hokkaido Univ. 4, in press.)
The production of deep-sea reversing thermometers, both protected
and non-protected, has greatly increased recently. Nearly two hundred
of them have been exported to the United States and many other coun-
tries of the world. S. Watanabe and S. Yoshino are two of the outstand-
ing makers.
Submarine Geology
In 1950 K. Hishida made an investigation on the sand drift in Ta-
kahania Harbor in the Japan Sea coast of Japan (KH, 1, 1950, 193).
T’. Ichiye published a series of papers on the beach erosion along
the southeastern coast of Osaka Bay. He propounded a theory of beach
erosion and suggested that the intense beach erosion is accompanied by
converging currents (US, 26, 1951; Reports on the Investigations of
Beach Erosion in the Southeastern Part of the Osaka Wan, 1951, 1952).
Hiroshi Niino is carrying on a very extensive geological survey in
several areas in the adjacent seas of Japan by boats belonging to the
Tokyo Fisheries University. His surveys are regarded to be very im-
portant from the standpoint of locating the fields of coal, oil and
natural gas.
ABBREVIATIONS
The following abbreviations are used in the text for expressing
names of the publications:
CREW rs sescasse Chikyubuturigaki Kenkyu Hokoku, Hokkaido Universi-
ty, Sapporo. ;
Jae NS3) Beso coe Bulletin of the Earthquake Research Institute, Tokyo
University, Tokyo.
TMB Aone cals Reports of the Research Institute for Fluid Engineer-
ing, Kyushu University, Fukuoka.
GU iris, sive ceceers Journal of Geography, Tokyo.
GMs 5 ctspeee rors Geophysical Magazine, Central Meteorological Observa-
tory, Tokyo.
GIN Bag he Seeley Geophysical Notes, Geophysical Institute, Tokyo Uni-
versity.
GSBieyn tees Bulletin of the Geographic Survey Institute, Tokyo.
fo Ben ee OEE Hydrographic Bulletin (Suiro Yoho), Japanese Hydro-
graphic Office, Tokyo.
Be ec Bulletin of Hokkaido Regional Fisheries Research La-
boratory, Yoichi, Hokkaido.
JCSBR ee Bulletin of Chemical Society of Japan, Tokyo.
JIPOCU_... Journal of the Institute of Polytechnics, Osaka City
University, Osaka.
SIME scvastotercts Journal of Marine Research.
SOM re eaeatc Journal of Oceanography.
70 EIGHTH PACIFIC SCIENCE CONGRESS
JOST ee eer: Journal of the Oceanographical Society of Japan,
Tokyo.
USS OM seoencoe Journal of the Japanese Society of Snow and Ice,
Tokyo. i
RET kus anes Chuo Kishodai Kenkyo Jiho (Journal of Meteorological
Research), Central Meteorological Observatory, Tokyo.
Kee ee Oe Kaiyo Hokoku (The Oceanographical Report of Central
Meteorological Observatory, Tokyo).
KK te ae Kaiyo to Kisho (Oceanography and Meteorology), Na-
gasaki Marine Observatory, Nagasaki.
KMOM_..... Memoirs of the Kobe Marine Observatory, Kobe.
KGS AGh have revyetoce Kisho Shushi (Journal of the Meteorological Society
of Japan), Tokyo.
MCAKU.... Memoirs of the College of Agriculture, Kyoto Univer-
sity, Kyoto.
MGR Mice crete Papers in Meteorology and Geophysics, Institute of
Meteorology, Tokyo.
MMOR ..... Maizuru Marine Observatory Report.
WNWARS gg 6 DOOD Monthly Weather Review, Washington, D.C.
NMOR ...... Nagasaki Marine Observatory Report.
OME iuctreuaitrters Oceanographical Magazine, Central Meteorological Ob-
servatory, Tokyo.
TPR OM irareleterers’s Papers and Report in Oceanography, Kobe Marine Ob-
servatory, Kobe.
OMIA Basgoc Records of Oceanographic Works in Japan, Japan
Science Council, Tokyo.
4 CR eae Teion Kagaku (Low Temperature Science), a publica-
tion in Japanese, edited by the Low Temperature Insti-
tute, Hokkaido University, Sapporo.
ARON OA eas ores Journal of the Tokyo Fisheries University, Tokyo.
IS Reha ee Umi to Sora (Sea and Sky), published by the Marine
Metecrological Society, Kobe Marine Observatory,
Kobe.
SR ce. Science Reports of the Tohoku University.
OCEANOGRAPHY IN MALAYA
THE ANALYSIS OF THE MARINE ECoO-SYSTEM AS A BASIS FOR PREDICTION
OF FisH AVAILABILITY IN MALAYAN SEAS.
By D. W. LE Mare
Sea fishing is essentially the exploitation of a natural resource
by the capture of a portion of wild stocks from an uncontrolled en-
vironment. The success of the operations depends on an intimate
knowledge of the nature and habits of these stocks. Normally, experi-
enced fishermen have a fairly good idea as to where and when to ex-
REPORT ON OCEANOGRAPHY 71
pect different species of fish. Very often, however, much time is wasted
in searching for the fish and from time to time there have been reports
from various parts of the world of unusually small catches or even of
complete failure of certain fisheries. On the other hand there are o¢-
casions when catches are normally poor. ‘The fishermen are unable to
explain these phenomena so that, from the point of view of financiers,
the fishing industry is generally considered to be inherently hazardous
and does not attract finance so readily as other enterprises. ‘There are,
of course, other factors but this element of uncertainty in fish produc-
tion is the largest factor which retards the expansion of the fishing in-
dustry on sound economic lines. It is clear, therefore, that for the fish-
ing industry to operate on an economic basis the fishermen must be
supplied with, inter alia, information as to where and when each spe-
cies or group of species of fish is available for fishing operations. This
is a task which should be given the highest priority in fishery investi-
gations as until it is known where, when and at what depth each spe-
cies of fish is available it is not possible to decide where to study the
nature of the bottom, the sea currents and the meteorological condi-
tions in which the fishing operations have to be carried out effectively
without a knowledge of all these factors. The need for reliable predic-
tion systems have been felt in different parts of the world and many
have been elaborated. The use of indicator organisms for the Herring
fishery in the North Sea is an example. It is of special importance in
the underdeveloped areas to know when and where to go, so that the
production of food for the world’s growing population may be in-
creased with a minimal waste of effort.
In Malaya, however, the catches of many of the tears in use at the
present moment consist of mixed fish and it has been found that while
these fish show a certain amount of food preference, they are mostly
plankton feeders and readily feed on other organisms if the food pre-
ferred are not available. Details of the results of the investigations on
the food and feeding habits of the fishes in Singapore Straits are given
in a paper by Tham Ah Kow (1950). There is evidence also that there
is a close correlation between wind and catches of certain species of
fish such as Stolephorus spp. This is not surprising in view of the fact
that the currents in Malayan seas are largely monsoon currents. From
the experience gained in the study of the fisheries of Malaya over the
years, it would appear also that rainfall and salinity variations as well
as variations in plankton play some part in the variation in availability
of fish.
In view of these considerations, it was decided that a concurrent
study of the physical, chemical and biological factors as related to the
- 72 EIGHTH PACIFIC SCIENCE CONGRESS
availability of fish should be made by the Research section of the Ma-
layan Fisheries Department. For this purpose it was decided to con-
centrate all observations in Singapore Straits since, besides other consi-
derations, one of the main gears used in this area is the fixed fish trap
known as the Kelong. The important features of this method of fish-
ing are: (1) in Singapore Straits its fishing intensity is practically con-
stant; (2) the fish in Singapore Straits are brought on to the long leads
of these traps by the tides and all fish lured into these traps are caught
by means of fine meshed lift nets; and (3) reliable records of the catch-
es of these stakes are easily obtainable. A detailed description of this
gear is given by Le Mare and Tham (1947). Observations on the fol-
lowing factors were made at regular fortnightly intervals during two
full years: (1) sea water temperature, (2) salinity, (3) phosphate ccn-
tent, (4) phytoplankton, and (5) copepod numbers. Full details of the
methods used in the measurement of these factors are given in a paper
by Tham Ah Kow (1953). It should be stated, however, that in the
case of phytoplankton the estimation of pigment content by Harvey’s
method as well as total counts were carried out. Data on wind-force
and rainfall for the period of the investigations were supplied by the
Malayan Meteorological Service.
In an attempt to study the effect of each of these factors on the
availability of fish the data so obtained were subjected to correlation
analysis by means of partial correlation. As the data are based on
fortnightly samples, they constitute time series and it is possible that
in each of these time series the value of the variable at one period of
time may influence its value in a succeeding period. In such cases the
use of partial correlation as an analytical tool would not be valid. How-
ever, according to Bartlett (1953) there should be no objection to the
use of partial correlation as a preliminary measure. If the partial cor-
relation coefficients are quite insignificant, there does not seem much
point in considering them any further. If the correlation coefficients
appear significant, then the terms of each of the series should be tested
for independence and if found to be independent the partial correla-
tion coefficients may be accepted as valid. This procedure has been
adopted. Where the terms of both series correlated are not indepen-
dent then the method of Fisher (1948) for series correlation is applied
to remove the effect of time. The results obtained by this correlation
analysis are shown in Figure I.
The main elements of the fish population in Singapore Straits are
Stolephorus spp. (anchovy), Clupea spp. (sprat), Chirocentrus spp. (do-
rab) and Scomberomorus spp. (Spanish mackerel). They are inter-
73
REPORT ON OCEANOGRAPHY
I qunyIy
ENVOIMINDIS ATIVOILSILVLS ATAVAONAd — — — — — —
‘LNVOIMINDIS ATIVOILSILVLS
| ‘dd$ SAdLNGQ0uIHO |
ALINITVS ee ets. = SSeS | TIVAINIVd |—-———| aLVHdSOHd |
qTaOLVEGdWaL |
|
| AHOWOTANIM |
| ‘ddS SAUOWONTANOOS ce aa ee |
-
SdIHSNOILLVIGYYALNI
‘ddS SNUYOHdATOLS
LNALNOO
LNAWSId
NOLANV'IdOLAH |
74. EIGHTH PACIFIC SCIENCE CONGRESS
related in that both Scomberomorus spp. and Chirocentrus spp. feed
voraciously on Clupea spp. and Stolephorus spp. These latter groups,
in turn, feed on zooplankton (especially copepods) and phytoplankton.
The physical and chemical elements of the environment play an im-
portant part in determining the availability of plankton as well as the
various elements of the fish populations. It is clear, therefore, that
the various elements of the marine eco-system in Singapore Straits are
very closely integrated.
In an attempt to study further the close relationship between the
fish population on the one hand and the environmental conditions, viz:
rainfall, windforce, temperature, salinity, phosphate, phytoplankton
and copepods, on the other, the method of multiple regression is used.
The multiple regression equation obtained may be expressed as fol-
lows:—
Xi, = — 49,903 — 395.61100 X, — 1.77415 X, — 1,105.75115 X,
511269182990) Xow 10:47 90a abo r7 Xen
where X,, = the monthly total catch of three kelongs in pounds,
14
X, = total rainfall in inches for that month,
X, = total wind speed in metres per second for that month,
X, == average temperature of the sea water in °C for that month,
X, = average salinity in °/,, for that month,
X, = average number of phytoplankton cells and/or chains of cells
per cubic metre for that month,
X, = average number of copepods per cubic metre for that month.
On testing the significance of the multiple correlation by working out
the value of “z’ it is found to be 0.87977 whilst the 0.1% point is
0.8657. ‘The multiple correlation is therefore clearly significant. The
adjusted multiple correlation coefficient squared is R? = 0.5566. The
standard error of estimate S is = 2316 Ibs. This is 14.44°% of the mean
monthly total catch for the two years under study.
The total catch for each month for the two years 1948 and 1949
has been calculated and compared with the corresponding actual total]
monthly catches in Table I. In the above regression equation it is
assumed that all the relationships are linear. If it were further re-
fined statistically by taking into account the curvilinear nature of some
of the relationships a much closer estimate would, in all probability,
be obtainable. The results of the multiple regression shows that if
predictions of the independent variates could be made with accuracy
a prediction system of sufficient accuracy for catches in Singapore Straits
is within reach. It would appear also from these results that, in the
exploration of new grounds, an intensive study of the marine eco-sys-
tem should yield a comprehensive picture of the habits and migration
of the fish stocks in a comparatively short time.
REPORT ON OCEANOGRAPHY 75
It is believed that this is the first time that a prediction system
for availability of fish has been developed, which shows the present de-
gree of accuracy when tested over a period of 24 months.
TABLE I
COMPARISON OF ACTUAL TOTAL CATCH AND CALCULATED
TOTAL CATCH
YEAR 1948 CALCULATED ACTUAL Cat. X 100 DIFFERENCE
ToTAL CATCH ToTAL CATCH ACTUAL AcT.-CAL. LBs.
January 6,428 7,029 91.45% + 601
February 15,799 17,153 92.11% +1,854
March A Dil 18,439 83.63 % + 8,018
April MTB 17,520 101.24% a AY
May 18,793 15,546 120.88% amOsea
June 17,967 17,618 101.98% = Gy)
July 14,809 11,270 131.40% TT Oye)
August 15,655 17,364 90.16% +-1,709
September 16,768 16,589 101.08% = ee)
October 20,917 20,586 101.86% =F Bl
November 17,483 20,585 84.93% +3,102
December 12,504 13,125 95.27% + 621
YEAR 1949
January 12,224 11,249 108.66% me | 5)
February 16,323 12,381 131.83% ao oe
March 17,983 19,821 93.07% +1,338
April 19,184 18,552 103.41% = Oey
May 17,809 18,445 96.55% + 636
June 16,261 16,070 101.19% am 9
July 14,956 17,192 86.99% + 2,236
August 18,501 21,765 85.00% +3,264
September 16,387 14,329 114.36% 2,008
October 15,163 O22, 96.44% DS)
November ~ 15,360 12,608 121.83 % enon
December 14,217 14,394 98.77 % + 177
REFERENCES
BARTLETT, M. S. 1935. “Some Aspects of the Time-Correlation Problem.”
Journ. Royal Statistical Soc. Vol. 98, p. 586.
FisHer, R. A. 1948. “Statistical Methods for Research Workers.” Tenth
Edition. Oliver & Boyd. London.
Le Mars, D. W. and THAM, AH Kow. 1947. “The Kelong Fishing Method.”
Fishery Conference convened by the United Kingdom Special Commis-
sioner for Southeast Asia at Singapore. Paper No. 1 (Mimeo.)
THamM, AH Kow. 1950. “A Preliminary Study of the Physical, Chemical
and Biological Characteristics of Singapore Straits.” Colonial Fishery
Publications. Vol. 1, No. 3, H. M. Stationery Office. London.
76 EIGHTH PACIFIC SCIENCE CONGRESS
OCEANOGRAPHY IN NEW ZEALAND
By A. W. B. Powe. and CG. A. FLEMING
I. INTRODUCTION
The years 1949 to 1953 have seen important advances in organiza-
tion and performance of oceanographic work in New Zealand. A re-
view of New Zealand oceanography presented in 1947 (Hefferd 1950,
Trans. Roy. Soc. N. Z. 77(5): 212-21) indicates the state of research
just prior to the 7th Pacific Science Congress. The stimulus provided
by the activities of the Oceanography Section of the 7th Congress in
New Zealand in 1949 has undoubtedly contributed to the advances
made since that date, which are documented by the bibliography of
New Zealand Oceanography 1949-53, compiled by the N.Z. Oceanogra-
phic Committee and tabled with this report.
In October, 1949, on the arrival of the naval survey vessels,
H.M.N.Z.S. Lachlan in New Zealand, her Commanding Officer, Com-
mander J. M. Sharpey-Schaefer, R. N., offered to collect data and ma-
terial for New Zealand scientists. To co-ordinate requests for data and
distribution of material, an Interdepartmental Committee on Ocea-
nography was formed, with representatives of Victoria University Col-
lege, Dominion Museum, Marine Department, and Department of Scien-
tific and Industrial Research. The Committee drew up a programme
of sampling and observation, and supplied the ship with bottom sam-
plers, containers, scientific log sheets, and arranged for analysis of wa-
ter samples, distribution of collections, mechanical analysis and petro-
logical examination of sediments, and perusal of echo-traces. In June,
1950, the Interdepartmental Committee pressed for the formation of
a National Committee fully representative of the many New Zealand
oceanographers attached to different institutions and departments, to
act as a national body competent to speak for New Zealand in ocean-
ographic matters.
_ A further stimulus to oceanography in this country was provided
by the opportunities afforded for some deep sea investigations arising
out of the visits of three oceanographic vessels—R.R.S. Discovery II
(1950-51), H.M.S. Challenger (1951), and the Danish Research Ship
Galathea (1951-1952).
The New Zealand National Committee on Oceanography (Secre-
tary J. W. Brodie) was formed in September, 1950, as an advisory re-
search committee of the Council of Scientific and Industrial Research,
and has since operated in effecting liaison, sponsoring research pro-
jects, and in advising the New Zealand Government on oceanographic
REPORT ON OCEANOGRAPHY 77
matters. In the field of physical oceanography, the committee through
its physical sub-committee, arranged for preparation of a bathymetric
map of New Zealand seas, for the collection of continuous echo sound-
ing profiles by naval vessels in New Zealand seas, particularly on vo-
yages between New Zealand, Australia, and the outlying islands, and
for “collector tracings” of all surveys to be available for scientific use.
Visiting expeditions (R.R.S. Discovery Il, H.M.S. Challenger, H.D.M.S.
Galathea) co-operated by supplying the committee with physical data
of local interest (soundings, temperatures, bottom samples, etc.). Also
molluscan material was allocated to two local specialists for study and
report. In general, the committee has effected liaison between New
Zealand workers in oceanography by assembling news-sheets, library
lists, and lists of vessels and equipment available for research work.
II. PuysicaAL (C. A. FLEMING)
Hydrographic Surveys by H.M.N.Z.S. Lachlan
Since her arrival in 1949, H.M.N.Z.S. Lachlan has been engaged on
hydrographic re-survey of New Zealand coasts. New charts have been
prepared of Foveaux Strait, Cook Strait, Wellington, Bluff, Lyttelton,
and Otago Harbours, Peterson Inlet, and the east coast between Banks
Peninsula and Wellington. Echo sounding surveys have clearly de-
lineated the position of the continental shelf-edge and have de-
monstrated the presence of submarine canyons in Cook Strait and off
the east coast of the South Island near Otago Peninsula, Banks Penin-
sula, and the Marborough Coast. In 1950, Lieutenant Commander B.
M. Bary, M.Sc., Ph.D., N.Z. Defence Scientific Corps, joined H.M.N.Z.S.
Lachlan as biologist, and the ship was equipped with a laboratory and
oceanographic gear. Mr. T. M. Skerman, M.Sc., Oceanographic Ob-
servatory, D.S.I.R., joined the ship when Lt. Commander Bary left to
further his studies at the National Institute of Oceanography.
In the course of hydrographic surveys, H.M.N.Z.S. Lachlan under-
takes routine observations of sea surface temperatures, obtains salinity
samples, bathythermograph records, bottom samples (using a Worzel
sampler supplied by Geological Survey) and plankton hauls. The re-
sulting collections and data are distributed to New Zealand oceanogra-
phers by the “Lachlan” sub-committee of the Oceanographic Commit-
tee.
Oceanographic Observatory, D.S.I.R.
The Oceanographic Observatory, Wellington, was formed in 1949
and is now organized as a unit of the Geophysics Division of the De-
partment of Scientific and Industrial Research for the study of hydro-
logical conditions in the seas around New Zealand. The present staff
78 EIGHTH PACIFIC SCIENCE CONGRESS
consists of three professional officers and two technicians. ‘The observ-
atory suffered a severe loss by the death in March, 1953, of Mr. W.
M. Jones, M.Sc., (N.Z.) B.A. (Oxon.), Director. In his contribution
to the development of physical oceanography in New Zealand, Mr.
Jones brought his long experience as a mathematical physicist in other
fields of geophysics.
An Admiralty wave recorder was installed at Greymouth, west coast
of South Island, in 1950, and ocean wave records obtained during a
three-month period. An examination of these records in conjunction
with weather information showed that there was satisfactory agreement
between the main features of meteorological situations and the resul-
tant wave spectra, and some graphical methods were evolved for eval-
uating the quantitative relations. The statistical relationships between
the observed sea surface and its spectrum have been studied. Some re-
sults have been published by Jessie K. A. Watters (1953, “Distribution
of height in ocean waves.” N. Z. J. Sci. Tech. B 34: 408-22), and others
will be published in a paper in preparation for the same journal by
N. F. Barber, and R. A. Wooding (“Some statistical features of sea
waves’).
The sea surface temperatures obtained from 1949 to 1952 from
merchant and naval ships and from surface recording thermographs in-
stalled on trans-Tasman and other vessels have been plotted on month-
ly charts as the basis for study of the surface hydrology of the south-
west Pacific by D. M. Garner (who has submitted a short account of
the results to this Congress). 1,600 salinity determinations, by the Do-
minion Laboratory (Wellington), are used to supplement the tempera-
ture data.
The hurricane at Suva in January, 1952, produced a microseismic
storm on the Milne Shaw seismograph, and the relations of the micro-
seisms to the position and intensity of the hurricane have been exam-
ined.
Geophysics Division, D.SJI.R.
Mr. J. W. Brodie has undertaken the filing and analysis of sound-
ing records received from ships of the Royal New Zealand Navy and
from other sources (including Discovery H, H.M.S. Challenger, and
H.D.M.S. Galathea). An account of the sea floor west of New Zealand
appears in N.Z. J. Sci. Tech. B 33 (5): 373-84, 1952. Contoured bathy-
metric charts of Cook Strait, Bay of Plenty, and Wellington Harbour
have been compiled and a description of a seamount rising from 1000
to 5000 fathoms, west of Waikato Heads, has been prepared. 12,000
drift cards have been obtained for release during 1953 in the south-
west Pacific to determine current movements.
REPORT ON OCEANOGRAPHY 719
Echo sounding profiles across the New Zealand continental shelf
are being accumulated for study. Many profiles show the shelf to be
terraced. The resurvey of Cook Strait by H.M.N.Z.S. Lachlan has
shown that a submarine canyon drains southward from the relatively
shallow (50-fathom) shelf of the western strait to depths in excess of
1,100 fathoms south of Cape Palliser. Shallow tributary channels cross-
ing the shelf between Nelson and Taranaki bear no relation to the
mouths of rivers. The resurvey has shown changes in the walls of the
Cook Strait Canyon since the early surveys of last century.
During 1950, D. J. Banwell and B. H. Olson measured electric
potential differences between points on shore spaced 2-3 kilometres
apart, considered due to tidal currents (Couper, 1953, Rep. 7th N.Z.
Sci. Congr. 3). Previous measurements (e.g. by Barber) were made in
the northern hemisphere. The results agreed fairly well with the theo-
retical argument of Longuet-Higgins, given the opposite polarity of
the earth’s field.
New Zealand Geological Survey |
Echo sounding and other bathymetric records were filed at the Geo-
logical Survey from 1949 until 1952 when the Geophysics Division un-
dertook their custody.
The topography and sediment of Mernoo Bank, an oval elevation
of the sea bottom rising from depths greater than 200 fathoms to 28
fathoms, 90 miles east of Canterbury, were described by Fleming and
Reed (1951, N.Z. J. Sci. Tech. B 32 (6): 18-30) on the basis of an echo
sounding survey by H.M.N.Z.S. Lachlan, and serial magnetometer profile
and sediment samples. The bank is interpreted as a tectonic dome,
composed of late Paleozoic to early Mesozoic indurated sediment, sculp-
tured by shallow radial submarine valleys. J. J. Reed has studied the
grain-size, sorting, and mineralogy of sediments of the Sumner estuary,
Canterbury (1951, N.Z. J. Scc. Tech. B33 (2): 129-37). From the Cha-
tham Rise west of the Chatham Islands, R.R.S. Discovery II dredged
coarse sediment at a depth of 170 fathoms containing pebbles of schist
and of phosphatised Miocene globigerine limestone (Reed and Horni-
brook, 1952, N.Z. J. Sct. Tech. B 34 (3): 173-88). Reed has prepared a
sediment map of Cook Strait based cn mechanical analysis of 170 sam-
ples, mostly collected with a Worzel sampler from H.M.N.Z.S. Lachlan.
Few samples had been obtained from the floor of the Cook Strait Can-
yon, but the general pattern indicates that sediment is coarse near the
canyon and fine on flat shelf areas distant from it. Calcite and siderite
concretions, some of them fossiliferous, a foot or two in diameter, are
regularly caught on fishing lines on the sides of the canyon and have
been studied by C. A. Fleming. The concretions contain fossils pro-
80 EIGHTH PACIFIC SCIENCE CONGRESS
bably of Pleistocene age and are bored by marine animals and support
a vigorous epifauna. These facts suggest that an area of geologically
young sediments is being destroyed by bottom scour on the sides of
the Cook Strait Canyon, leaving the more resistant concretion on the sea
bottom, where currents are sufficient (in depths of 100 to 120 fathoms)
to prevent sediment accumulating.
B. L. Wood and I. McKellar (Geological Survey, Invercargill) have
begun a study of bottom topography and sediment in Foveaux Strait
off the East Coast of Otago. A submarine lignite from Foveaux Strait
has been shown by pollen analysis to be Plio-Pleistocene in age, and
to represent a cool climate (Couper, N.Z. J. Sct. Tech. B 33 (3): 178-86).
By arrangement with the Galathea Expedition authorities R. A.
Couper is working on the spores and pollen grains in a sediment core
obtained by H.D.M.S. Galathea in Milford Sound. Preliminary re-
sults suggest that it may be possible to determine the rate of sedimenta-
tion in the glacially over-deepened basin with the rock bar near the
entrance to the sound owing to the appearance of pollen from intro-
duced Cupressus trees at the top of the core.
Some further information on the White Island Trench, described
by Fleming at the 7th Pacific Science Congress (1953, Proc. 7th Pacific
Sct. Congr. 3:210-12), is now available as the result of echo sounding
and a gravimetric survey. The trench, which is interpreted as the
submarine continuation of the Rangitaiki Graben, has now been traced
north eastward into the Bay of Plenty to depths in excess of 1300 fath-
oms, and additional work has shown that a parallel depression runs
seaward on its west side, defining the ridge on which stands the White
Island volcano. Gravity surveys of the Bay of Plenty have shown that
the landward part of the trench is an area of negative anomaly, with
a maximum difference of 50 milligals between the trench and the up-
lifted blocks which bound it on either side. Neither the gravity profiles,
nor the echo traces are evidence that the depression has particularly
steep walls, although these have been mapped geologically as faulty.
The bottom relief offshore corresponds in detail with the gravity pro-
file along the coast.
III. BrotocicaL (A. W. B. Powe Lt)
A considerable amount of work that may be classified under the
heading of biological oceanography is at present in progress at the
several University Colleges, Museums and other scientific institutions
in this country and an outline of the nature and scope of this work
follows:
REPORT ON OCEANOGRAPHY 81
Although many of the titles in the Oceanographic Committee’s
bibliography and many of the topics included in my list work in pro-
gress suggest specialized zoological and botanical scope rather than
oceanographic, it should be conceded that New Zealand is a young
country and that the systematics and biology of many groups are still
inadequately known.
All such papers collectively will eventually form an indispensable
background for future biological oceanographic investigation.
Published Biological Work
The published papers are representative of most phyla but mol-
luscan and algal studies predominate with 33 titles for the former
and 16 for the latter.
Protozoa. ‘Two papers by B. N. Bary on Sea-water discoloration.
Portfera. One paper, The Kirk Collection of Sponges, by H. B.
Fell.
Coelenterata. ‘Two papers on Ctenophores from Cook Strait by
P. M. Ralph and C. Kabery and The Actinaria of New Zealand by G.
Parry, which includes a check-list of recorded and new species.
Echinoderma. Five papers by H. B. Fell: “The Constitution and
Relations of the New Zealand Echinoderm Fauna,” “Echinoderms from
Southern New Zealand,” “The Occurrence of Australian Echinoids in
New Zealand Waters,” and several papers on littoral and deep-sea ophi-
uroids. Also a paper on Holothuria by W. H. Dawbin.
Polyzoa. A monograph of Tertiary Cheilostomata by D. A. Brown
and two papers by G. H. Uttley contain many references to the syste-
matics and distribution of recent species.
Mollusca. ‘Thirty-three papers by C. Borland, R. K. Dell, C. A.
Fleming, J. E. Morton, R. M. Cassie, Rapson, and A. W. B. Powell.
In addition to systematics there are papers on life-histories, feeding
mechanisms, animal communities of the sea bottom, population stu-
dies, biogeographic provinces, bipolarity and the dispersal of southern
high latitude species.
Crustacea. ‘Three papers on the Spiny Crayfish (Jasus lalandi) by
C. A. Bradstock, two on brachyura by L. R. Richardson, one on new
species of Scyllarus and Ctenocheles by A. W. B. Powell, and one on Am-
phipoda by D. E. Hurley. N. de B. Hornibrook has described ‘“‘A new
Family of Living Ostracoda with Resemblances to some Palaeozoic Bey-
richiidae” and has published a monograph ‘Tertiary and Recent Ma-
rine Ostracoda of New Zealand, their Origin, Affinities and Distribu-
tion,” including a systematic revision of the Cytheriidae.
Protochordata. Eight papers on New Zealand Ascidians by B.
Brewin.
82 EIGHTH PACIFIC SCIENCE CONGRESS
Pisces. Five papers by J. A. F. Garrick, J. M. Moreland, W. J.
Phillips, and L. R. Richardson.
Mammalia. Southern Ocean Seals, two papers by E. G. Turbott
and the “Elephant Seals of Campbell Island” by J. H. Sorensen.
The algal papers deal with systematics, ecology, zonation and al-
gal provinces. The authors are M. P. Ambler, J. A. Carnahan, V. J.
Chapman, R. F. de Berg, U. V. Dellow, and V. W. Lindauer.
Biological Work in Progress in New Zealand
FISHERIES BRANCH, MARINE DEPARTMENT, WELLINGTON.
Survey of Snapper (Pagrosomus auratus) spawning grounds in the
Hauraki Gulf, Auckland, to log the distribution and density of eggs
and larvae.
Routine trawls in the Hauraki Gulf to record the seasonal varia-
tion in the composition of fish stocks.
Investigation of the spawning areas for Tarakihi (Dactylopagrus
macropterus) in the Gisborne-East Cape area.
VICTORIA UNIVERSITY COLLEGE, WELLINGTON.
The Zoology Department is encouraging students to specialize in
the systematics of groups. In recent years students of the Department
have investigated Amphipoda, Cephalopoda, Macrozooplankton and Os-
tracoda. Staff members are at present working on Coelenterata, Hiru-
dinea, Crustacea Brachyura, Echinodermata and Pisces. Cee > reer ease Pere =
f=
ep)
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EIGHTH PACIFIC SCIENCE CONGRESS
144
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NOURISHMENT OF CENTRAL PACIFIC STOCKS OF TUNA 145
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146 EIGHTH PACIFIC SCIENCE CONGRESS
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148
EIGHTH PACIFIC SCIENCE CONGRESS
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FIGURE 8
DEVELOPMENT AND CONSERVATION OF THE TUNA
FISHERIES OF THE PACIFIC
By MILner B. SCHAEFER
Inter-American Tropical Tuna Commission
Scripps Institution of Oceanography
La Jolla, California, U.S.A.
In recent years, it has often been pointed out that in order to keep
up with the food demands of a growing population, man must turn
to the sea as a major source of protein food. In point of fact, the
utilization of the food resources of the sea has been increasing at a
rapid rate for some decades. With the development of steam propul-
sion for fishing craft late in the last century, followed by the develop-
ment of diesel engines, the sea fisheries have expanded rapidly in scope
and intensity of fishing. At the same time, improved techniques of
preserving and transporting fish have broadened the market for the
catches. ‘This expansion of the fisheries has been most rapid, of course,
in those seafaring nations whose technological development is most
advanced (Canada, the United States and Japan in the case of the
Pacific Ocean). Other nations, however, have also participated in the
development, and there is, at present, considerable time and money
being expended by various agencies to assist the nations with little
development of fisheries to expand them by the application of modern
technological advances imported from other areas, or by the forced
evolution of their indigenous methods.
Because of problems of preservation of the catch, as well as econo-
mic factors, the fisheries closest to the ports of landing tend always to
be most heavily exploited. Furthermore, the hazardous nature of sea-
faring, with the consequent need for larger and more costly craft to
exploit distant oceanic fishing areas, favors the development of the in-
shore fisheries. In consequence, many of the demersal and inshore fish
populations are now fully or nearly fully exploited. The Pacific sal-
mon fisheries, for example, are certainly not capable of any increase in
catch, except as better management may increase somewhat the effi-
ciency of utilization of the populations of these species. “The Eastern
Pacific halibut stocks are controlled by scientific management, having
been overfished in the 1920’s and 1930’s. The formerly large fisheries
for sardines have declined both on the western and eastern sides of the
Pacific. ‘There is some question as to how much of the decline of the
149
150 EIGHTH PACIFIC SCIENCE CONGRESS
sardine catch is due to fishing, and how much is to be attributed to
changes in the oceanic environment; but there seems to be no question
that the populations of this species have no possibility of supporting
a much greater catch than has been attained in the past. The herring
fisheries of the North Pacific, on both sides of the ocean, seem to be
rather fully exploited. The great Japanese trawl fisheries of the East
China Sea and adjacent areas have been so heavily fished that they are
now subject to regulation to curtail the intensity of fishing. Certainly
there are yet demersal and inshore fish stocks that are little utilized,
such as the hake and pollock of the Northeastern Pacific. In the main,
however, the new frontier of commercial fishing is the exploitation of
the oceanic fishes of the high seas.
The potential food production from fisheries of the high seas is
doubtless very large. The cost of harvesting this crop is, however, also
large. Under present economic circumstances, therefore, development
of high sea fisheries is confined to those species which occur in high
local concentration and have a relatively high unit value, so that the
catch per unit of fishing effort has sufficient value to offset the high cost
of production. Few pelagic oceanic organisms meet these requirements
at the present time. The whales are, of course, an outstanding example.
Among the fishes, the tunas support one of the few major fisheries of
the high seas in the Pacific. The several species of tunas aggregate in
sizable schools, occur in relatively large concentrations in certain areas
of the sea, and command a high market price. ‘They have, therefore,
become the object of increasingly extensive and intensive fisheries.
TUNA FISHERIES OF THE PACIFIC
Five kinds of tunas are the objects of important commercial fish-
eries in the Pacific. ‘They are:
Albacore—Thunnus germo
Yellowfin—Neothunnus macropterus
Skipjack—Katsuwonus pelamts
Bigeye—Parathunnus sibi
Bluefin—Thunnus thynnus, T. orientalis, T. maccoyt
Several other species support fisheries of a local nature and of
minor importance, including Kishinoella tonggol, the northern bluefin
of Australia, and the several species of Euthynnus. The bonitos, genus
Sarda, which support important fisheries, are not usually considered
tunas in the strict sense.
The fisheries for tunas in the Pacific have developed rapidly dur-
ing the last three decades, and at present are among the most valuable
fisheries of this ocean. In the United States, the tunas rank first in
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 151
total value of all categories of fish products. In Japan, they are of
major importance both for domestic use and for export. They support
an important industry in Peru, and are of growing importance in Aus-
tralia. It is, perhaps, most convenient to consider the development
and present status of the fisheries by species.
Albacore
The albacore (Thunnus germo) occurs in commercial quantities
in temperate waters of both northern and southern hemispheres. Tuna
fishing in the Eastern Pacific had its inception in the first decade of
this century in Southern California, where albacore occur during the
summer and fall months in inshore surface waters, where they may be
captured by trolled lures or by pole and line, using live bait for chum.
Small craft, fishing only a few miles from shore, supplied the infant
canning industry. Since the fishing depended on the seasonal occur-
rence in inshore water of an oceanic, migratory fish, availability was
notably erratic from year to year. By 1925, however, the fishery pro-
duced 22 million pounds of albacore. In 1926 the albacore failed to
appear in appreciable numbers, and the landings dropped to two-and-
a-half million pounds. They continued scarce for a decade in waters
of California and Baja California covered by the tuna fleet. The er-
ratic and seasonal occurrence of albacore led the fishermen tv turn to
the tropical tunas, the yellowfin and skipjack, which range north to
California during the summer, and to extend their operations south-
ward, first off the Mexican coast and later farther south, in order to
extend the season of fishing and to find greater concentrations of these
species. The failure of the albacore fishery in 1926 gave tremendous
impetus to the development of the fishery for tropical species, which will
be discussed further below.
In 1936, albacore began to appear again in greater numbers in
California inshore waters, and have since continued to support an im-
portant amount of fishing. In 1937, fishermen off Oregon, Washington,
and British Columbia discovered that albacore occurred there, too, in
the summer at some little distance offshore, and began to fish for them.
They have continued to do so since.
The present albacore fishery of the Eastern Pacific extends from
Baja California to British Columbia, being pursued only during the
summer and fall months when the fish appear in surface schools in
waters not far from shore, and can be captured by trolling lures or by
pole and line using live-bait chum. Some fishing is done as far as 150
miles from the coast, but most of it is done within a much narrower
range. Albacore are known, from observations of research vessels, to
occur a good deal further offshore than they are now fished. Because
152 EIGHTH PACIFIC SCIENCE CONGRESS
of the dependence of the fishery on the seasonal, inshore occurrence of
the fish, which varies a good deal from year to year, probably in re-
sponse to variations in oceanographic factors, the success of the fishery
varies widely, the variability increasing as one goes north. Present
magnitude of the fishery is indicated by the statistics for 1950, when
73 million pounds were landed, 62 million of these in California.
On the western side of the Pacific, tuna fishing is much oldei. Fish-
ing for tunas in the waters adjacent to Japan has been engaged in by
fishermen of that nation since ancient times. Not until the introduction
of motorized fishing vessels in the first decade of the present century,
however, did the fishery begin to assume any large proportion, so that
the development of the modern fishery is contemporary with that of
the Eastern Pacific.
The ‘summer’ albacore fishery, in the adjacent seas of Japan, is
similar to the fishery in the Eastern Pacific. It depends on schools of
fish which appear in inshore waters about April or May, reach their
greatest abundance in about June, and disappear in the late summer
or fall.
Albacore, and other tunas as well, are also fished in Japan in sub-
surface waters by means of floating long-lines. “Ine long-line fishery
for albacore has, as a result of explorations by Japanese research vessels,
been extended eastward to the longitude of the Hawaiian Islands.
The long-line fishery has its greatest success during the winter months
and appears, according to Uda and Tokunaga (1937), to be most pro-
ductive in the region of the North Pacific convergence near latitude
30°N.
Albacore is not a preferred species for domestic consumption in
Japan, but finds a ready market in the United States. Therefore, much
of the catch is exported either as canned tuna, or as frozen tuna which
is canned in the United States. The Japanese albacore catch in 1950
amounted .to 65 million pounds, and was nearly double that amount
oy ey
Small quantities of large albacore are captured on long-lines by
the local fishery in the Hawaiian Islands, incidental to fishing for yel-
lowfin and bigeye tuna. Small commercial quantities are fished off
Chile and southern Peru.
The albacore fisheries of the Pacific appear to be capable of con-
siderable expansion, both by development of fisheries in the southern
hemisphere, which are now little exploited, and by further offshore
development of the North Pacific fisheries. Exploration of the offshore
distribution of albacore in the Northeastern Pacific is planned to be
undertaken during the coming winter by agencies of the U. S. Govern-
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 153
ment and the State of California, so development of an offshore fishery
in this area may not be far distant.
Bluefin
These are tunas of temperate waters, occurring in both the northern
and southern hemispheres. Commercial fisheries are conducted for them
off California, Japan and southern Australia (Sydney to Tasmania).
The bluefin tunas of these three regions are probably distinct species
(Thunnus orientalis of Japanese waters, T. thynnus in the Eastern
Pacific, and T. maccoyi in the Australian area), according to morpho-
logical data of Godsil and Holmberg (1950), although some taxono-
mists, for example Fraser-Brunner (1950), place them all in a single
cosmopolitan species. In any event, it seems quite certain that the three
groups being fished in the Pacific are quite distinct from one another.
The bluefin of California waters is taken commercially only by
purse seines. ‘The fishery is normally confined to the summer months,
June to September, with best fishing in July and August when the
schools of fish appear near the surface in waters not far from shore.
The supply is erratic from year to year, and average total production
is small, and highly variable, between 3 million and 22 million pounds
in various years of the past decade.
The Japanese fishery for bluefimn tuna is also pursued mainly in
oceanic waters within a hundred miles or so of land, by means of nets,
traps, and long-lines. A considerable catch is made with nets and traps
close to the shore in certain regions. Some bluefin are, however, taken
by long-lines, incidental to fishing for ether species, on the high seas
many hundreds of miles from land. Available statistics on bluefin tuna
landings in Japan indicate that there, also, the production is erratic,
varying irregularly between 2 million and 52 million pounds in various
years from 1936 to 1951.
The Australian representative of the bluefin tuna, unlike that of
the California fishery, bites readily on both trolled lures and live bait.
According to Serventy (1941) these are small, immature fish ranging
from 6 to 35 pounds in weight. The fishery is conducted by small ves-
sels during the summer months in inshore waters. Presumably the
larger, adult fish occur elsewhere. Until 1951, fishing was done by trol-
ling only. In that year a live-bait vessel conducted fishing trials with
some success, and in 1952 and 1953 a small fishery has been prosecuted
using the live-bait, pole and line technique.
It appears that the Australian fishery, which now produces only a
few hundred tons per year, is capable of considerable expansion.
Prospects for increased production in other areas are not possible to
154 EIGHTH PACIFIC SCIENCE CONGRESS
estimate at this time, in the absence of adequate information on the
distribution and biology of fish involved.
Yellawfin
The yellowfin tuna (Neothunnus macropierus) is a tropical species
occurring everywhere in Pacific equatorial waters between approx-
imately, the surface isotherms of 18°C. It is the object of a large
fishery on both sides of the Pacific Ocean and in the Central Pacific
westward of the International Date Line. Considerable stocks, not now
exploited, are known to exist in the eastern equatorial Pacific between
the International Date Line and the presently fished seas adjacent to
the American West Coast.
As noted previously, the fishery for the tropical tunas began in
California shortly after the initiation of fishing for albacore. The sea-
sonal and erratic nature of the albacore fishery led the fishermen and
canners to turn to the tropical yellowfin and skipjack tunas. The
fishery began as a seasonal one in waters of Southern California and
Northern Baja California, but the fishermen soon learned that by going
farther south yellowfin and skipjack could be taken during a greater
part of the year, more regularly, and in greater abundance. ‘This
stimulated the building of large vessels which could stay at sea longer
and range further from port. The failure of the albacore fishery in
1926 gave strong impetus to the expansion of the tropical tuna fishery.
By 1930 vessels were fishing regularly far down the Mexican coast, and
beginning to venture even farther south.
As the vessels ventured further into the tropics on longer voyages,
problems of preserving the catch multiplied. During the 1930's ex-
periments were made with mechanical refrigeration, and finally brine
freezing of the fish was developed. At the same time, the vessels evolved
into large craft of the high seas capable of operating thousands of miles
from home on long voyages. By 1938 vessels from California ports were
operating over the entire area from Southern California to Ecuador,
and offshore over 200 miles. ‘The outbreak of World War II curtailed
sharply the long range fishing, because many of the larger vessels were
converted to military duty and various restrictions were placed on the
operations of the remaining vessels. With the cessation of hostilities,
however, the fleet again grew rapidly and prosecuted the fishing even
more vigorously. The long range fishery has been extended to northern
Peru, and provides now an even greater share of the catch than before
the war.
This fishery by United States vessels produces by far the major
part, over 90%, of the catch of yellowfin, as well as of skipjack, tuna
taken in the Eastern Pacific. Small local fisheries developed during
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 155
the 1920’s and 1930’s in Mexico and Costa Rica. During the war, with
' the increased demand for tuna in the United States, a local fishery was
started in Peru for yellowfin and skipjack tunas, and this continues to be
an important part of the Peruvian fishing industry, greatly exceeded
in production, however, by the fishery for bonito. Recently a small
local fishery has been initiated in Ecuador.
The growth of the production of yellowfin tuna from the Eastern
Pacific is illustrated in Figure 1, in which the production of skipjack
is also depicted. These two tropical tunas are taken in the same waters
on the same voyages. The very rapid postwar growth of the fishery is
evident from this chart. There is evidence that the production of yel-
lowfin is no longer increasing, but the upward trend of skipjack produc-
tion is being maintained.
Over 75% of the yellowfin and skipjack tunas taken in the Eastern
Pacific are captured by means of pole and line, live bait being employed
to chum the tunas to the vessel and to induce them to strike the lures.
Bait fishes are several species of small fishes, mostly of the families Clu-
peidae and Engraulidae, captured in the territorial waters of the several
countries bordering on the Eastern Pacific. “The remainder of the catch
is made by means of purse seines. “These methods capture only the
surface-schooling component of the population. No commercial fishery
has been developed for the large, old yellowfin tuna, analogous to the
Japanese and Hawaiian long-line fisheries.
A parallel, but geographically even more extensive, development
of the yellowfin tuna fishery has taken place in the Western Pacific
Ocean. Yellowfin tuna occur during the summer months in Japanese
home waters, and for many years have been fished there by nets, long-
lines, and pole and line, but did not contribute an important share of
the tuna catch until the southward expansion of the 1930’s.
Surveys by government vessels and commercial companies, about
1931, discovered that yellowfin tuna and bigeye tuna (Parathunnus sibi)
are distributed throughout the tropical southwest Pacific, and can be
taken commercially in sub-surface waters of the high seas by means of
long-lines. This led to the initiation of a commercial fishery which
was, of course, very soon terminated by World War II. Immediately
following the war, the Japanese fishery expanded back into this area
as rapidly as permitted by the Occupation authorities. ‘This fishery is
still expanding, and at the present time operates throughout the tropical
western Pacific as far east as the Phoenix Islands and south to the Coral
Sea, Arafura Sea and Banda Sea. This long-line fishery captures, in
addition to yellowfin tuna, quantities of bigeye tuna, spearfishes, and
sharks. The tunas captured by this means are mostly very large fish,
a good deal larger than those taken at the surface. Available recent
156 EIGHTH PACIFIC SCIENCE CONGRESS
records of the Japauese fishery indicate that it is annually producing
about 30 million pounds of yellowfin tuna and a similar quantity of
bigeye tuna, with the catch increasing year by year.
Fishing of surface schooling yellowfin tuna is not extensive in the
western Pacific. During the 1930’s the Japanese developed a moderately
large fishery for surface-schooling skipjack in the Caroline, Marshall,
and Marianas Islands, employing the live-bait technique. Small quanti-
ties of yellowfin were taken incidentally. ‘This fishery depended, of
course, on supplies of live bait which are not extensive in the Mandated
Islands (now the Pacific Trust Territories), and which have not been
available to Japanese fishermen since the war. Except for local sub-
sistence fishing by islanders of the ‘Trust Territories, and some fishing,
mostly by means of traps, in the Philippines, the tuna fishery of the
western tropical Pacific is almost exclusively a long-line fishery at the
present time.
There is also a small fishery for yellowfin tuna and bigeye tuna in
the immediate vicinity of the Hawaiian Islands. During the summer
months, skipjack tuna are taken by live-bait techniques from surface
schools, and a few yellowfin are taken incidentally. The main catch
of yellowfin, however, is made by long-lines, which capture large sub-
surface tunas, averaging over 100 pounds each. The catch is almost
entirely marketed for local consumption as fresh fish, and, hence, the
volume is limited by the local market. The catch is about two million
pounds a year, two-thirds of it being yellowfin and one-third bigeye.
Research by the Pacific Oceanic Fishery Investigations of the U. S.
Fish and Wildlife Service, during the past three years, has demonstrated
that large concentrations of sub-surface yellowfin and bigeye tunas are
to be found in equatorial waters of the Central and Eastern Pacific,
east of the present Japanese fishery. Greatest concentrations occur
between the equator and the southern boundary of the counter-equa-
torial current, being associated with a zone of current convergence in
those latitudes. Sizable surface schools have also been observed in the
vicinity of the Line Islands and Phoenix Islands. It has also been dem-
onstrated by various commercial explorations that surface-schooling yel-
lowfin occur in some numbers in the Marquesas, Societies, and Tuamo-
tus. These stocks of yellowfin are at present not fished commercially.
It would appear that the yellowfin tuna production from the Pacific
Ocean will continue to increase, both by expansion to presently unfished
areas and by further increase in production from some regions now
being fished.
Bigeye
The bigeye tuna, Parathunnus sibi, is fished in the same regions
as the yellowfin tuna, and by the same gear. It constitutes an important
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 157
part of the long-line catches, as noted above. Occurrence in surface
schools is less frequent, so that this species is an incidental and insig-
nificant part of the catch where surface fishing, using live bait or by
purse seines, is the means of production.
In the Eastern Pacific fishery along the coasts of the Americas, the
few bigeye captured are included with the yellowfin in the catch statis-
tics. “The exact percentage of bigeye included is not known, but exam-
ination of landings on a sampling basis indicates it is not large, probably
not over 2 or 3 per cent.
Skipjack
As indicated above (pp. 154-155) the skipjack, Katsuwonus pelamis,
occurs in surface schools in the region of the Eastern Pacific fishery in
the same general localities as the yellowfin. It occurs sometimes in pure
schools and sometimes in mixed schools with yellowfin of similar size.
It is fished both by live bait and by purse seine, just as is the yellowfin.
The development of the fishery for yellowfin and skipjack in the
Eastern Pacific has already been described. The growth of the skipjack
catch is shown with that for yellowfin in Figure 1. Although both species
have been fished since the initiation of the fishery, yellowfin has been
the preferred species, commanding a higher price and being somewhat
easier to preserve, particularly before the days of brine freezing. In
consequence, the expansion to distant areas during the 1930’s was
directed primarily at the yellowfin tuna. The postwar growth of the
fishery has, on the other hand, depended on skipjack to an increasing
extent. It appears that with the increasing exploitation of the yellowfin
stock of the Eastern Pacific, and the inevitable accompanying decrease
in catch per unit of effort, the fleet has turned increasingly to skipjack,
the catch of which has, in recent years, risen a good deal in relation to
that of yellowfin.
Skipjack is the most important species in the Japanese tuna fishery,
the landings at the present time being over 200 million pounds per year.
This species of tuna has been an important article in the Japanese diet
since ancient times, but its capture was confined to coastal waters unul
introduction of powered fishing vessels early in this century. The off-
shore fishery grew rapidly thereafter, encompassing not only Japanese
home waters, but regions to the south to well below the equator, and
eastward through the Mandated Islands. The fish are captured almost
exclusively by pole and line, using live bait for chum. Negligible
quantities are taken incidentally by long-lines. Purse seining is reported
to have been tried experimentally in recent years.
During the 1930's, skipjack fishing in the Caroline, Marshall, and
Marianas Islands was rapidly developed, in spite of scarcity of live bait
158 EIGHTH PACIFIC SCIENCE CONGRESS
in those areas, through combined activities of government agencies and
commercial companies, until in 1937 a peak production was ‘obtained
amounting to 40 thousand metric tons. ‘The advent of the war, of
course, terminated this fishery. At present it is inactive except for local
fishing by islanders on a subsistence basis.
A small fishery for skipjack occurs during the summer months in
the vicinity of the Hawaiian Islands, producing, on the average, about
9 million pounds per year. ‘The limiting factor here is the great scar-
city of live bait which is required for the capture of skipjack.
Essentially unexploited regions in which skipjack are known to
occur in commercial quantities include all of Oceania and the seas to
the north of New Zealand, the Coral Sea, and the Arafura and Banda
Seas. In addition to problems of transportation and marketing, the
scarcity of live bait in part of this area deters the development of
fisheries there.
POTENTIAL FOR FUTURE DEVELOPMENT
From the foregoing very brief review of the Pacific tuna fisheries,
it is evident that the several species are very unevenly exploited in dif-
ferent parts of their range. Certain regions support rather intensive
fisheries, while no fishing at all is done in others.
With the demand for tuna increasing year by year, utilization of
presently unexploited and underexploited tuna stocks may be expected
to follow in due course, as their exploitation becomes profitable, either
as a result of increased demand, and consequently increased price, or
as a result of lower harvesting costs due to improved or novel fishing
methods. Certainly the potential annual harvest from the Pacific tuna
fisheries is a good deal larger than that being taken at the present time.
PROBLEMS OF CONSERVATION
Since the tuna resources throughout much of the Pacific Ocean are
obviously not being exploited to anywhere near their maximum yield,
problems of maintaining the supply through management are, from the
broad viewpoint, of secondary importance at the moment, and the in-
terests of most tuna researchers have, consequently, been centered on
problems connected with expansion and development of the fisheries.
The tuna stocks are not unlimited, however, and the rapid growth of
the fisheries will inevitably bring forth in the not too distant future the
necessity of conservation of the stocks to produce maximum yields. The
fishery for the tropical tunas of the Eastern Pacific is already sufficiently
intense and some of the nations having interests in that fishery have be-
come concerned about the possibility of the approach of overfishing.
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 159
Intensive fishing of a tuna species in one part of a large geograph-
ical area, while it is unfished in other parts, can scarcely result in over-
fishing if the species consists of a single large population migrating
freely throughout the area. It may happen, however, that there are a
number of sub-populations, so that the fishery is bearing very heavily
on one or more of these while leaving the others untouched. {n the
latter case, the sub-populations being fished may easily be overfished
while the others remain untouched.
Like much else concerning the biology and life history of the tunas,
the degree of distinctness of the tuna populations of the several regions
of the Pacific is imperfectly known. For the yellowfin tuna, it has been
fairly well demonstrated by morphometric studies by Godsil and Green-
hood (1951), Schaefer (1952) and Royce (1953) that the yellowfin
tuna of the Eastern Pacific are distinct from those of other parts of the
Pacific. Royce’s work shows that there are also further distinctions be-
tween populations in other regions of the Pacific. For the albacore, on
the other hand, morphometric comparisons of fish from the eastern and
western north Pacific have, so far, failed to show significant differences,
and the recent recovery off Japan of a specimen tagged off California
tends to indicate that the North Pacific albacore may be a single large
population. Respecting skipjack, work in progress by the author in-
dicates that the skipjack of the region of the Eastern Pacific fishery are
probably morphometrically different from those of Oceania. This work
has, however, not been completed. So far as the tropical yellowfin and
skipjack tunas of the Eastern Pacific are concerned, then, there is evi-
dence to support the belief that they are distinct from those of the other
regions of the Pacific, so that a very intense fishery could reach the
point of overfishing.
The very rapid growth of the Eastern Pacific fishery for these
species, and the very incomplete knowledge of their biology, ecology,
and life history, has caused concern that the fishery could become over-
developed, with consequent overfishing of the tuna stocks of this area.
Since most of the tuna catch is made by means of live bait, there has
also been concern lest the populations of bait fish be overfished with
disastrous effects on the yield of tuna. ‘This situation, obviously, re-
quires that scientific investigations be conducted, in order to provide
an adequate foundation of knowledge of the biology and ecology of
the fishes concerned, and of the effect on them of the increasingly in-
tense fishery.
Although our knowledge of the ways of life of the tunas is small,
certain things we do know. We know that they are creatures of the
open sea, inhabiting the reaches of the ocean beyond the territorial
160 EIGHTH PACIFIC SCIENCE CONGRESS
limits of any nation. ‘They spawn in the open sea far from land, the
juvenile stages require no littoral nursery grounds, and the adults are
completely oceanic in their foraging. Such knowledge of their move-
ments and aggregations as we have, indicates that they are oriented to
the water masses and currents of the ocean rather than to any geo-
graphical feature per se. The fisheries which harvest them are, for the
most part, completely oceanic; nearly all of the catch is made well out-
side the territorial limits of any nation.
THE INTER-AMERICAN TROPICAL —TUNA COMMISSION
Under accepted concepts of freedom of the seas, and free access to
the resources thereof, the tunas are truly an international resource, and
their scientific investigation and conservation is an international prob-
lem. Being cognizant of the need for adequate knowledge of the re-
source on which the tropical tuna fishery is based, the governments of
the United States of America and the Republic of Costa Rica in 1950
entered into a Convention establishing an Inter-American Tropical Tuna
Commission having as its objectives gathering and interpretation of
factual information to facilitate maintaining the populations of yellow-
fin and skipjack tunas, and of other fishes taken by tuna fishing vessels
in the Eastern Pacific Ocean, at a level which will permit maximum
sustained catches year after year. The Convention provides for the
subsequent adherence of any other nations having a mutual interest
in these fish populations.
The Commission employed a scientific staff and initiated its in-
vestigations in January 1951. Headquarters are maintained at the
Scripps Institution of Oceanography, with which the Commission’s staff
works in close co-operation. A regional office at Puntarenas, Costa Rica,
has also been established for the study of the biology and ecology of
bait fishes.
The scientists of the Commission have a unique opportunity to
study the dynamics of an important commercial fishery during the
period of its growth and development. Fortunately, suitable statistical
and other records have been maintained to measure the changes in
catch and abundance of the tunas during the period of greatest growth
and development of the fishery from 1931 to the present time. ‘This
is an unusual and most fortunate situation. Most often in the past,
little interest has been evinced in the investigation of commercial
marine fisheries, particularly those of an international character, until
the fishery has become so intense that economic distress of the industry
has demanded remedial measures. ‘This has most often been so long
after the period of underfishing that suitable biological statistics for the
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES 161
period of early development of the fishery are fragmentary or unobtain-
able. In the case of the tropical tunas, we have, then, a unique op-
portunity for the study of the dynamics of a large, oceanic fishery, the
results of which will be of far-reaching value not only to the welfare
of the tuna fisheries, but to the knowledge of the dynamics of com-
mercial fisheries in general.
The investigations of the Commission have, so far, centered on the
compilation and analysis of the records of the fishery in order to derive
quantitative measurements of changes in the fish population in re-
sponse to changes in intensity of fishing and catch, both currently and
historically. For the adequate interpretation of such data, there is, of
course, required considerable knowledge of the life histories and biology
of the species concerned, and a fair start has been made on obtaining
this. Knowledge of the relation of the behavior of the tunas to the
spatial and temporal changes in the oceanic environment is also essen-
tial to understanding of their population dynamics. Investigation of
these matters is a costly line of research, requiring work at sea with
large, expensive vessels. “The budget of the Commission has been in-
adequate as yet to do as much in this direction as is desired, but, with
the assistance of the Scripps Institution of Oceanography, the California
State Fisheries Laboratory, and the U. S. Fish and Wildlife Service,
a good deal of work in this direction has been gotten underway.
Most of the investigations of the Commission are yet unready for
announcement of results. Intermediate studies along some lines of re-
search are, however, nearing completion and will be published in the
near future. Scientific contributions of the Commission will be pub-
lished in a series of Bulletins. Staff members also publish minor papers
in standard journals. Annual progress of investigations is reported on
to the member governments and to the public by means of publication
of a series of Annual Reports.
LITERATURE CITED
FRASER-BRUNNER, A. 1950. The fishes of the family Scombridae. Ann. Mag.
Nat. Hist., Ser. 12, vol. iii, pp. 131-163.
GopsiIL, H. C.and E. K. HoLMBerc 1950. A comparison of the bluefin tunas,
genus Thunnus, from New England, Australia, and California. Calif.
Div. of Fish and Game, Fish. Bull. no. 77, 55 pp.
GopsIL, H. C. and E. C. GREENHOOD 1951. A comparison of populations of
yellowfin tuna, Neothunnus macropterus from the eastern and central
Pacific. Calif. Div. of Fish and Game, Fish. Bull. no. 82, 32 pp.
KISHINOUYE, K. 1923. Contribution to the comparative study of the so-called
scombroid fishes. Jowr. Coll. Agriculture, Imp. Univ. Tokyo, vol. 8,
no. 3, pp. 293-475.
162 EIGHTH PACIFIC SCIENCE CONGRESS
Royce, W. F. 1953. Preliminary report on a comparison of the stocks of
yellowfin tuna. Proceedings, Indo-Pacific Fisheries Council. (in press)
ScHAEFER, M. B. 1952. Comparison of yellowfin tuna of Hawaiian waters
and of the American West Coast. U. S. Fish and Wildlife Service,
Fish. Bull., vol. 52, pp. 353-378.
SERVENTY, D. L. 1941. The Australian tunas. Australia, Coun. Set. Ind.
Res., Pamphlet no. 104, 40 pp.
Upa, M. and E. ToKUNAGA 1987. Fishing of Germo germo (Lacepede) in
relation to the hydrography in the north Pacific waters. Bull. Imp.
Soc. Sci. Fish., vol. 5, no. 5, pp. 295-3800.
163
DEVELOPMENT AND CONSERVATION OF TUNA FISHERIES
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RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN
By Hirosur NAKAMURA! and YosHIo HiyAMa 2
Because the tunas and marlins fisheries are important in this coun-
try, numerous works have been produced by our biologists over a long
period of time, but here we shall describe some recent achievement of
our biologists as regards these fishes.
(1) Taxonomy
Only a few amendments and additions have been made since Kishi-
nouye (1923) reviewed the fishes of Thunnidae. Jordan and Evermann
(1926) established gen. Kishinoella for Neothunnus rarus Kishinouye
and added Neothunnus itosibi. Nakamura (1939) thought the latter
had no difference from N. macropterus, and Serventy (1941) thought
the former was a synonym of K. tonggol. Kamohara (1940) changed the
name of the Japanese bluefin tuna to Thunnus thunnus Linn. and that
of the albacore to G. alalunga.
About Xiphiiformes, since Nakamura (1937) reviewed Istiophoridae
and Xiphiidae of the West part of the Pacific, Hirasaka and Nakamura
(1947) made a few amendments and additions. They established gen.
Kajtkia for Makaira mitsukurii Jordan & Snyder, added K. formosana
and established gen. Marlina for Makaira marlina Jordan & Hill, and
added Eumakaira nigra N.g. n.sp.
(2) DiIsTRIBUTION AND MIGRATION
As most of the fishes are caught by the long line in this country,
the method of tagging is quite difficult though so many efforts have
been made. Now the tagging method for the pole and line fishing is
under investigation with the cooperation of both authors.
Therefore, our knowledge on the migration of these fishes is merely
based on the seasonal change of the fishing grounds, about which so
many data have piled up already. On the other hand, since Kishinouye
(1923), so many biologists like Kimura (1941-1949), Uda (1935-52), and
Aikawa (1933) have discussed the oceanographic conditions of the hab-
itation of these stenothermal fish species from various points of view.
Recently Nakamura worked out the distribution of these fish kinds by
1 Nankai Regional Fisheries Research Laboratory, Kochi, Japan.
2 Fisheries Institute, Faculty of Agriculture, Tokyo University, Japan.
165
166 EIGHTH PACIFIC SCIENCE CONGRESS
the recent twenty-year records of Japanese Tuna fleet activities. His
work was done mainly to see geographical distribution as regards the
density of fish in fishing grounds throughout the seasons. To measure
the density of fish, he used the number of certain species of fish caught
by one hundred hooks in a long line by the records brought by com-
mercial boats, which is a sort of average catch, catch per amount of fish-
ing effort. Many maps showing the density distribution of each fish
species for each month of each year and of the average of the past
twenty years have been prepared for printing. Here a part of it is in-
troduced as an example.
Thunnus orientalis. Though Kishinouye (1923) thought the
southern limit of the distribution would be 30°N, Nakamura (1936,
’38, °43, ’49, 51) reported the existence of fishing ground from March
to June in the Northeastern part of the South China Sea, North from
15°N in the East of Luzon, and near Formosa and the Ryukyu Islands.
Nakamura also thought that the fish in the East of Luzon would be in-
dependent from the fish that appear near Tanegashima (130°E, 30°N)
from March to December, judging from their size composition and
sexual maturity. Beside these, Shimada (1951) reported the occurrence
of this species in the equatorial area from June to September, and Jor-
dan & Evermann (1926) reported its occurrence in Hawaii and in the
U.S. Pacific coast. The northern limit reported by Isahaya (1935) is
near 50°N in Karafuto. The amount of catch of this species by the
Japanese fleet was near to nothing in 1940, but has been much better
since 1950.
Germo germo. Uda and Tokunaga (1937) thought the fish caught
by the Japanese fleet can be divided into three groups: a small-sized
group in coastal waters off Honshu, a medium-sized group in the grounds
further off shore, and a large-sized group found further East from the
former. Each ot the three groups migrates clockwise, and intermingle
at the point near 155°E, 40°N, having its southern limit in subtropical
convergence. From the data Nakamura compiled, he thought that al-
though it is evident that the bigger size of fish is found in the more
eastern grounds, it is hard to separate the group as the change is so
continuous, and it might be caused by the economical size selection of
fishing by the commercial boats. The fishing ground usually goes South
during the fishing season at a speed of 2-6 miles per day, and in March
it arrives at the Southern extremity, that is, subtropical convergence,
and it goes back to somewhat North in April. ‘The size of the fish in the
front line of this southward migration is usually bigger than that at
the tail, which is found somewhere North from the former. South from
the subtropical convergence to the equator, a large-sized group is found,
RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN 167
though the density is thin. This is supposed to be the spawning group
which came from the North, but this is not confirmed by accurate evi-
dence. One somewhat distinct group of large-sized fish usually goes south-
westward from October to February in a thick density, at 135°E, 12-
25°N; but the relation with other groups is still not clear.
Parathunnus mebachi. The previous works on the migration of
this fish discuss mainly the oceanographic conditions of the fishing
grounds, but Nakamura, by his density distribution maps, found the
following facts. The two separate fishing grounds exist in this area.
The one at about 40°N in the Northwest Pacific in September is
stretched along the latitude line to the date line eastward, and then
goes down South, like G. germo; but the speed is slower than that, so
this fishing ground is always located at the North of the front of that.
Another group of fishing grounds exists all year round at 8 to 12°N,
a contact line of equatorial countercurrent and North equatorial cur-
rent. These are not homogeneously stretched as a line, but form some
isolated groups within them. He still has no definite idea on the rela-
tionship between the two. Besides these, a fishing ground appears in
20-25°N during a certain season. ‘The relationship of this to others is
unknown. Kamimura (not printed) recognized the phenomenon that
the modes in size-frequency curve differ every other year in the North-
west Pacific.
Neothunnus macropterus. Past works are concerned mainly with
the oceanographic conditions of habitation, especially the temperature
of the water. However, Nakamura by his density distribution maps
cbserved the following facts. ‘The size of fish is generally smaller in
the coastal area of Japan and gets larger in the grounds offshore to the
Fast. A remarkable change of size composition is also recognized ac-
cording to latitude in the same longitude in the same season, and the
border lines of this change are at 3-4°N and 7-8°N, which, he thinks,
are caused by the influence of the South equatorial current, the equa-
torial countercurrent, and the North equatorial current. Also, he thinks
that the different fish groups would come in and out by the influence
of the monsoon in the seas which are surrounded by land or islands
such as South China Sea, the Sulu Sea, the Celebes Sea, the Banda Sea
and others. The same fact would be supposed to exist at the coastal
waters off Timor, the Small Sundas and other equatorial areas in the
Pacific. Before Nakamura’s work it was believed that most condensed
grounds are in the equatorial countercurrent, but he thinks it would
be somewhere South from the contacting area of the equatorial counter-
current and the South equatorial current.
168 EIGHTH PACIFIC SCIENCE CONGRESS
Hiyama wants to add, seeing Nakamura’s distribution maps, that
this species has less tendency of southward migration shown in the fore-
going two species, and that the thick distribution is found in the area
more influenced by the coast, or by the existence of islands or lands.
Hiyama and colleagues are now working on the morphometry of the
above-mentioned four species after the method used by U.S. biologists,
but it is still too early to report the results.
Neothunnus rarus. As the catch by the Japanese fleet is not enough
to indicate the distribution and migration, the only fact that Nakamura
can see is that this species is distributed in the area near the Indo-
Australian Archipelago, with its northern limit at the Ryukyu Islands.
Istiophoridae. Tetrapturus angustirostris has remarkable oceanic
character in general and is thinly distributed in the tropical and sub-
tropical area. A thick fishing ground appears usually off the east coast
ef Formosa from November to January.
Istiophorus orientalis has wide distribution in the West Pacific,
having a rather coastal character. ‘The center of the distribution is
thought to be in the Indo-Australian Archipelago, and its northern
limit is in the North polar front. From May to August a thick fishing
ground appears near the Philippines and Formosa. Kajikia mitsukuriz
has more oceanic character than the former, and has also a wide dis-
tribution extending to the North Pacific, with its center at subtropical
convergence. ‘The dense fishing grounds appear at 30-40°N in autumn,
and moves south in October. And from March to June the dense
group of the grounds appears in 20-30°N. After K. mitsuwkurit went
down south, fishing grounds in 30-40°N are occupied by X7phias gladius.
The distribution of K. formosana is not yet well known. Eumakaira
nigra has a remarkable oceanic character, distributed in tropical and
subtropical area. ‘This species has its distribution range south of that
of K. mitsukuri. ‘This shows a northward migration from May to
July, with its northern limit at subtropical convergence, and reaches to
20-26°N zone nearly one month later than K. mitsukuri. ‘The female
of this species is always bigger than the male. The latter rarely exceeds
100 kgm. in weight, so the size composition of the catch should be con-
sidered based upon the sex ratio of it. Marlina marlina is confined
within the coastal area of the Indo-Australian Archipelago, as already
indicated. ‘This also has a size difference between the sexes, the male
rarely exceeding 120 kgm. Xzphias gladius is thought to have world-
wide distribution, but in the Northwest Pacific the dense distribution
is recognized by Nakamura at the North from subtropical convergence
beyond 43°N. In August a good fishing ground is usually formed in
150-155°E, 40-43°N, which moves south thereafter, just like Germo
RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN 169
germo, down to the east of Bonin Island in March, and fades away.
Nakamura and others (1951) think that the spawning ground of this
fish would be in the South from subiropical convergence, because they
found sc many juveniles of this in this area.
(3) SPAWNING HABIT
In general, Nakamura thinks these oceanic fishes have a long spawn-
ing season, sometimes almost all year round, and have their spawning
grounds widely distributed throughout tropical and subtropical, and
sometimes even in temperate zones in the Pacific, based upon the recent
data of collection of eggs and juveniles of these fish kinds, done inten-
sively by Japanese research vessels. Regarding the spawning grounds
of Katsuwonus pelamis, many biologists, such as Schaefer & Marr
(1948), Shimada (1951), and Wade (1950, 1951) reported juveniles
from various parts in the Pacific. Yabe (unpublished) got ten indi-
viduals of 5 to 10 mm. long juveniles of this species from the collection
of our research vessels during 1947 to 1952 from near Ryukyu, off Hon-
shu and in Micronesia in April to September. Suda (unpublished)
found large numbers of juveniles from stomach contents of tunas and
marlins caught from various parts of the Pacific, and found evidence
that the smaller (5 to 20 mm. long) juveniles are obtained from the
area south from subtropical convergence, and the larger ones (over 20
mm. long) were found in the area to the north. About Thunnus ori-
entalis, Kishinouye (1923) thought that this would spawn in June
and July in the area off Honshu, but later Kawana (1935) reported its
spawning in the Japan Sea, and Nakamura (1938, 1939) found the
ripened ovarium in the fish caught near the Philippines from the middle
of April through the middle of May. About Germo germo, Watanabe
(1939) reported that he obtained the ripened ovarium in the fish caught
near Midway Island, and Schaefer (1948) and Brock (1943) got some
idea on this matter. The data obtained by Japanese research boats are
now under investigation. About Parathunnus mebachi, Shimada (1951) -
found ripened ova in the fish caught from the area 143-160°E, 1-10°N
from June to September, and thought that the spawning season might
continue later than this period. Recently biologists on board the re-
search boat of Nankai Regional Fisheries Laboratory succeeded in the
artificial fertilization of this fish in the equatorial region. About N.
macropterus, Nakamura (1939, ’43, ’49, °51) reported that he found
ripened ova in the fishes caught in the South China Sea from March
to May. Wade (1950) thought the season near the Philippines was
from May to August, and afterwards he obtained the juveniles (9.4—37.5
mm. long) and could assure both the locality and the season. Shimada
170 EIGHTH PACIFIC SCIENCE CONGRESS
(1951) found spent fishes in the area 150-200 miles northwest off Ka-
pingamarangi Island at the beginning of August. Schaefer (1948) and
Schaefer & Marr (1948) found juveniles in Central America from
January to May. About N. rarus we have nothing to add to Delsman
& Hardenberg (1934) and Serventy (1942).
About Tetrapterus angustirostris, Nakamura (1937, °38) found
ripened ova in the fish caught east of Formosa and thought this would
spawn in November and December in this area. About Istiophorus
orientalis, Nakamura (1932) reported in December the ripened ovarium
in the fish caught from Molucca Strait. And later he (1938, ’42, ’43)
also found ripened ova and juveniles and witnessed the spawning be-
haviour near Hainan Island, near Formosa and east of Luzon Island
from April to September. Near Japan so many juveniles were found
since Uchida (1937). Also, recently Nakamura and his stafi obtained
so many juveniles from tropical areas such as Micronesia from June to
September. However, they have some difficulty identifying these as
this species, because the difference from E. nigra is not assured in juve-
niles yet, and the latter species matures and grows abundant in the area
in this season. About Kajikia mitsukuri, Nakamura found ripened
ovarium as usual from April to May near Formosa, and thought that
this also spawns in the same season around Bonin Island. Recently
Nakamura and his staff found ripened ovaria in the fishes caught from
the equatorial area from June to September. About Eumakaira nigra,
Nakamura (1938, ’42, ’49) found ripened ovaria of fish caught east of
Luzon Island, and thought this would spawn from April to August near
Luzon and Formosa. Recently he and his staff found another spawning
ground near Bonin Island in the same season, and in the equatorial
area of the Pacific they also found grown-up fishes from June to October.
About the above-mentioned four species Nakamura (1944) found the
seasonal change of both size composition and sex ratio, which changes
remarkably after the spawning season. The juveniles of Xiphias gladius
in the Atlantic Ocean have been reported already. About that in the
Pacific, Yabe (1951), Nakamura and others (1951) reported 11-35 mm.-
long young, and there were plenty of larger young found in the stomach
contents of tunas and marlins.
(4) AcE AND GROWTH
The age determination of these groups of fishes has been made by
counting the number of rings in the centrum of the vertebrae. Aikawa
(1937) reported the growth of K. pelamis by this method and size
composition of the catch. Afterwards Aikawa and Kato (1938) worked
on the growth of G. germo, N. macropterus and T. orientalis by the
RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN 171
same method. Ban (1941), Higashi (1941), Ikebe (1939, ’40, ’41) re-
ported the growth of K. pelamis, N. macropterus, P. mebachi, G. germo
by the method of size composition of the catch. Kimura (1932, ’35)
worked on the same problem about T. orientalis and N. macropterus,
by the seasonal change of size of catch in the Izu Region. Recently
Moore (1951) reported that of N. macropterus near Hawaii. ‘The
growth rates obtained by these workers have big differences from each
other. For example, about that of N. macropterus a big difference
exists between Aikawa & Kato, Kimura and Moore. ‘To examine the
numerous samples to get the accurate age composition of population,
instead of size composition, the centrum reading method is inconven-
ient. So now the scale reading method is going to be established by
Hiyama, as the scale samples can be collected easily from numerous
specimens before the fish is dissected. It is already affirmed by him that
the ring in the scale is formed once a year during a certain long season.
It will be published in the near future, and now the age determination
by this method is going on to get the age composition of the catch.
(5) Frepinc Hasir
Many reports have already been published on the stomach contents
of these fishes, but many of them are fragmental and not enough to
see the relationship between foods and migration. Nakamura (1936)
noticed the difference of the stomach content of N. macropterus in the
Celebes Sea between the fish caught during the Northeast wind season
and that caught during the Southwest wind season, and by this. he
guessed the seasonal change of the fauna in this region. Suyehiro (1936)
reported the stomach contents of K. pelamis and he also (1938) re-
ported that of N. macropterus, P. sibi, and T. orientalis. A group
of biologists with us are now working systematically on the stomach
contents of these fishes, but the results are not ready for publication.
In general, these carnivorous oceanic fishes have less tendency to be
selective as to food, as so many various fishes may be found in their
stomachs, sometimes including the garbage of vegetables thrown out
from boats. Marlins are generally taking larger fish having greater
swimming power than tunas. And the latter, though variation accord-
ing to species is shown, generally has a tendency of a plankton feeder
in any degree, and it is most conspicuous at G. germo. With reference
to fishing, the reason why some school of tunas would not take the bait
was investigated by Suyehiro (1938) and others.
LITERATURE CITED
AIKAWA, H., 1933. Fishery conditions on the Pacific coast for skipjack, tuna,
and sauries. Proc. Sci. Fish. Assoc., vol. 5, No. 4, pp. 354-869. (Jap.)
172 EIGHTH PACIFIC SCIENCE CONGRESS
ArkAwa, H., 1937. Notes on the schools of bonito along the Pacific Coast
of Japan. Bull. Japanese Soc. Sci. Fish., vol. 6, No. 1, pp. 18-21. (Jap.)
—_———. and M. Karo, 1938. Age determination of fish. 1. Bull. Jap.
Soc. Sci. Fish., vol. 7, No. 2, pp. 79-88. (Jap.)
BAN, Y., 1941. Search for southern tuna fishing grounds. South Sea Fish.,
vol. 7, No. 9, pp. 10-21. (Jap.)
Brock, V. E., 1943. Contribution to the biology of the albacore (Germo
alalunga) of the Oregon Coast and other parts of the North Pacific.
Stanford Ichth. Buli., vol 2, No. 6, pp. 199-248.
DELSMAN, H. C. and J. G. F. HARDENBURG, 1934. De Indische zeevischen en
zeevischerij. Biblio. Nederland. Ind. Nat. Ver., No. 6, pp. 330-343.
GopsIL, H. C., 1948. A preliminary population study of the yellowfin tuna
and the albacore. California Div. Fish and Game, Fish. Bull. No. 70,
90 pp.
-- 1949. A progress report on the tuna investigations. California
Fish and Game, vol. 35, No. 1, pp. 5-9.
and E. C. GREENHOOD, 1951. A comparison of the population of
yellowfin tuna, Neothunnus macropterus, from the eastern and Central
Pacific. California Div. Fish and Game, Fish. Bull. No. 82.
HicasHl, H., 1941. Utilization of fishery by-products from the South Sea.
(10). South Sea Fish., vol. 7, No. 3, pp. 36-438. (Jap.)
IKEBE, K., 1939. On the age of yellowfin tuna taken in Palau waters. South
Sea Fish News, vol. 3, No. 10, pp. 4-8. (Jap.)
, 1940a. Age and measurements of tunas in Palau waters. Ibid.,
vol. 4, No. 1, pp. 2-4. (Jap.)
, 1940b. Measurement of yellowfin tuna taken south of the Mar-
shall Islands. Tbid., vol. 4, No. 2, pp. 2-5. (Jap.)
, 1940c. Measurement of albacore and yellowfin tuna taken in
Saipan waters. Ibid., vol. 4, No. 5, pp. 68-67. (Jap.)
, 1941a. Measurement of yellowfin tuna from the Equatorial] Coun-
ter Current area. Ibid., vol. 5, No. 3, pp. 5-13. (Jap.)
, 1941b. A contribution to the study of tuna spawning grounds.
Ibid., vol. 5, No. 4, pp. 9-12. (Jap.)
JORDAN, D. S. and B. W. EvERMANN, 1926. A review of the giant mackerel-
like fishes, tunnies, spearfishes and swordfishes. Occ. Paper California
Acad. Sci. XII.
and J. O. SNYDER, 1901. Description of nine new species of fishes
contained in Museum of Japan. Jour. Coll. Sci. Imp. Univ. Tokyo, XV.,
po. 801-311.
HrIrASAKA, K. and H. NAKAMURA, 1947. On the Formosa spear-fishes. Bull.
Oceanogr. Taiwan, No. 8, pp. 9-24.
ISAHAYA, T., 1986. On the bluefin tuna in the adjacent waters of Karafuto.
Hokkaido Suishi Jumpo. (Jap.)
KANAWA, T., 1935. Bluefin tuna spawns in the Japan Sea. Swisan Kenkyu-
shi. 380, pp. 284-286. (Jap.)
KAMOHARA, T., 1940. Fauna Nipponica, vol. XV, Fas. II, No. V. (Jap.)
KimurA, K., 1932. Growth curves of bluefin tuna and yellowfin tuna based
on the catches near Shigedera, on the west coast of Prov. Idu. Bull.
Japanese Soc. Sci. Fish., vol. 1, No. 1, pp. 1-4. (Jap.)
RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN 173
KimurA, K., 1935. Statistical analysis of the catch by deddle nets, along the
coast of Suruga Bay. Rec. Oceanogr. Works, vol. 7, No. 1, pp. 1-36. (Jap.)
, 1941. Skipjack fishing. Fish. Technol. Lect. Ser., No. 4, 36 pp.
—-—————., 1942a. Tuna and spearfish fishing conditions. JIbid., No. 5, 122
pp. (Jap.)
, 1942b. Oceanic resources: Offshore fisheries. Sci. Sea, vol. 2,
No. 3, pp. 142-147. (Jap.)
, 1949. Atlas of skipjack fishing grounds, with data on the al-
bacore grounds. Kuroshio-shobo. Tokyo.
KISHINOUYE, K., 1919. The larval and juvenile stages of the Plecostei. Proc.
Sci. Fish. Assoc., vol. 8, No. 2, pp. 49-53. (Jap.)
, 19238. Contribution to the comparative study of the so-called
scombroid fishes. Jour. Coll. Agri., Imp. Univ. Tokyo, vol. 8, No. 3,
pp. 293-475.
Moors, H. L., 1951. Estimation of age and growth of yellowfin tuna (Neo-
thunnus macropterus) in Hawaiian waters by size frequencies. U. S.
Fish and Wildlife Serv., Fish. Bull. 65, pp. 133-149.
NAKAMURA, H. 1932. On the ripe ovarian ova of the sailfish (Istiophorus
orientalis). Zool. Mag., vol. 44, pp. 272-283. (Jap.)
, 1935. On the intersexuality of the skipjack (Katsuwonus pe-
lamis.) Trans. Nat. Hist. Soc. Formosa., vol. 25, No. 141, pp. 197-198.
(Jap.)
, 1936. On the feeding habit of yellowfin tuna (Neothunnus ma-
cropterus) from the Celebes Sea. Ibid., vol. 28, No. 148, pp. 1-8. (Jap.)
, 1938. Preliminary report on the habits of the black tuna (Thun-
nus orientalis). Zool. Mag., vol. 50, No. 5, pp. 279-281. (Jap.)
, 1939a. Notes on the differences between Neothunnus macropte-
rus and Neothunnus itosibi. Formosan Fish. Mag. No. 288, pp. 27-32.
(Jap.)
, 1939b. Report on the investigation of Thunnidae from Formosan
waters. Formosa Gov.-Gen. Fish. Exp. Sta. Publ. No. 18, pp. 1-15. (Jap.)
, 1943. Tunas and marlins. Sci. Sea., vol. 8, No. 10, pp. 445-459.
(Jap.)
, 1949. Tunas and tuna fishing. Takeuchi-shobo, Tokyo. (Jap.)
, 1951. A review of the tuna fishing ground based on past in-
vestigations. Rept. Nankai Regional Fisheries Research Lab. No. 1,
(With appendix charts). (Jap.)
, Studies on the fishes of the family Istiophoridae, in the adjacent
Seas of Formosa. (Jap.)
1. 1987a. Habits of the fishes of the family Istiophoridae in the Seas of
Formosa. Especially on Furai-kajiki (Tetrapturus angustirostris)
Zool. Mag., vol. 49, pp. 233-238.
2. 1937b. Report on the investigation of marlins and swordfishes from
Formosan Waters. Rept. Formosan Gov.-Gen. Fish. Exp. Sta. No.
105-84 pp:
3. 1938. On the spawning habit of Kuro-kajiki (Wakaira mazara). Zool.
Mag., vol. 50.
4. 1940. On the spawning habit of the sailfish (Istiophorus orientalis).
Tbid., vol. 52.
174 EIGHTH PACIFIC SCIENCE CONGRESS
5. 1941. On the body temperature of some fishes of the family Thunni-
dae and Istiophoridae. Proc. Sci. Fish. Assoc., vol. 8, Nos. 3 and 4,
pp. 256-268.
6. 1942. Habits of the marlins observed in the adjacent seas of For-
mosa. Ibid., vol. 8.
7, 1944a. Sexual differences of the sizes of the fishes of the family
Istiophoridae. Nat. Hist. Formosa., vol. 35, Aug.
8. 1944b. Seasonal differences of the sizes of the fishes of the family
Istiophoridae.
a. Kurokajiki Makaira mazara. Ibid., vol. 35, Oct.
9. 1944c. Seasonal differences of the sizes of the fishes of the family
Istiophoridae.
b. Shirokajiki Makaira marlina.
c. Other marlins. Jbid., vol. 35, Dec.
NAKAMURA, H. and others, 1951. Note on the life history of the swordfish
Xiphias gladius. Jap. Jour. Ichth., vol. 1, No. 4, pp. 264-271. (Jap.)
ScHAEFER, M. B., 1948a. Morphometric characteristics and relative growth
of yellowfin tuna (Neothunnus macropterus) from Central America.
Pacific Sci., vol. 2, No. 2, pp. 114-120.
, 1948b. Size composition of catches of yellowfin tuna (Neothun-
nus macropterus) from Central America, and their significance in the
determination of growth, age and shoaling habits. U.S. Fish and Wild-
life Serv. Fish. Bull., vol. 51, No. 44, pp. 197-220.
, 1948e. Spawning of Pacific tunas and its implications to the
welfare of the Pacific tuna fisheries. Trans. 13th North Amer. Wildlife
Conf., pp. 366-371.
—-——— and J. C. Marr, 1948a. Spawning of yellowfin tuna (Neothun-
nus macropterus) and skipjack (Katsuwonus pelamis) in the Pacific
Ocean off Central America with description of juveniles. Jbid., vol. 51,
No. 44, pp. 187-195.
SERVENTY, D. L., 1941. The Australian tunas. Couneil Sci. Indust. Res.,
Australia, Pamphlet No. 104, pp. 1-48.
, 1942. Notes on the economics of the northern tuna (Kishinoella
tonggol). Jour. Council Sci. and Indust. Res. Australia, vol. 15, No. 2,
pp. 94-100.
SHIMAD, B. M., 195la. Juvenile oceanic skipjack from the Phoenix Islands.
U. S. Fish and Wildlife Serv., Fish. Bull. 64, pp. 129-131.
---__—__—.,, 1948b. Contribution to the biology of tunas from the Western
Equatorial Pacific. Jbid., Fish. Bull. 62, pp. 111-119.
Supa, A., 1953. Juvenile skipjack from the stomach contents of tunas and
marlins. (not issued) (Jap.)
SUYEHIRO, Y., 1936. The reason why the bonito does not take baits. Fish.
Invest. (Suppl. Rpt.) Imp. Fish. Expt. Sta., No. 3, Paper No. 31,
pp. 14-16. (Jap.)
, 1938. The study of finding the reason why the bonito does not
take to the angling-baits. Jour. Imp. Fish. Expt. Sta., No. 9, Paper
No. 69, pp. 87-101. (Jap.)
TAUCHI, M., 1940a. On the stock of Thunnus orientalis (T. & S.). Bull. Jap.
Soc. Sci. Fish., vol. 9, No. 4, pp. 183-185. (Jap.)
, 1940b. On the stock of Neothunnus macropterus (T. & S.).
Ibid., vol. 9, No. 4, pp. 136-188. (Jap.)
RECENT STUDIES ON TUNAS AND MARLINS IN JAPAN 175
TaucHI, M., 1940c. On the stock of Germo germo (Lacepede). I[bid., vol. 9,
No. 4, pp. 139-141. (Jap.)
, 1941. On the stock of Huthynnus vagans (L.). Bull. Jap. Soc.
Sci. Fish., vol. 11, Nos. 5 and 6, pp. 179-183. (Jap.)
Upa, M., 1935a. On the estimation of favourable temperature for longline
fishing of tunny. Bull. Jap. Soc. Sci. Fish., vol. 4, No. 1, pp. 61-65. (Jap.)
, 1935b. The result of simultaneous oceanographical investigations
in the North Pacific Ocean adjacent to Japan made in August 1933.
Jour. Imp. Fish. Expt. Sta., No. 6, Paper No. 48, pp. 1-180. (Jap.)
, 1936. Locality of fishing center and shoals of “katuo” Euthyn-
nus vagans (Lesson) correlated with the contact zone of cold and warm
currents. Bull. Jap. Soe. Sci. Fish., vol. 4, No. 6, pp. 385-390. (Jap.)
, 1938. Correlation of the catch of “katuo” in the waters adjacent
to Japan. Ibid., vol. 7, No. 2, pp. 75-78. (Jap.)
, 1939. On the characteristics of the frequency curve for the
catch of “katuo” Euthynnus vagans (Lesson) referred to the water
temperature. JIbid., vol. 8, No. 4, pp. 169-172. (Jap.)
, 1940b. A note on the fisheries condition of “katuo” as a function
of several oceanographic factors. Ibid., vol. 9, No. 4, pp. 145-148. (Jap.)
, 1940c. On the recent anomalous hydrographical conditions of
the Kuroshio in the south waters off Japan proper in relation to fisheries.
Jour. Imp. Fish. Expt. Sta., No. 10, Paper No. 74, pp. 231-278. (Jap.)
, The body-temperature and the bodily feature of “katuo” and
“samma.” Bull. Jap. Soc. Sci. Fish., vol. 9, No. 6, pp. 231-236. (Jap.)
, 1952. On the relation between the variation of the important
fisheries condition and the oceanographical condition in the adjacent
waters of Japan. Jour. Tokyo Univ. Fish., vol. 38, No. 3.
and E. ToKUNAGA, 1937. Fishing of Germo germo in relation
to the Hydrography in the North Pacific waters. Bull. Jap. Sec. Sev.
Fish., vol. 5, No. 5, pp. 295-300. (Jap.)
Ucuipa, K., 1937. Kagaku (Science), vol. 7, pp. 540-546, 591-595. (Jap.)
WADE, C. C., 1950. Juvenile forms of Neothunnus macropterus, Katsuwonus
pelamis and Euthynnus yaito from Philippine seas. U.S. Fish and Wild-
life Serv., Fish. Bull. No. 58, pp. 395-404.
-——_———, 1951. Larvae of tuna and tuna-like fishes from Philippine
waters. Ibid., Fish. Bull. 57, pp. 445-485.
YaABE, H., 1951. Juvenile swordfish, Xiphias gladius. Jap. Jour. Ichth., vol.
1, No. 4, pp. 260-263. (Jap.)
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EIGHTH PACIFIC SCIENCE CONGRESS
182
ARE THE WORLD-WIDE DECLINES IN SARDINE
CATCHES RELATED?:*
By Joun C. Marr and James E. BOHLKE
South Pacific Fishery Investigations, U.S. Fish and Wildlife Service
450-B Jordan Hall, Stanford, California, U.S.A.
Large fluctuations in the catches of marine fishes, especially pelagic
species, have long been known and may, in a sense, be considered to
have given the original and major impetus to the birth and growth of
the science of fishery biology. Indeed, such fluctuations have been
observed to occur in so many different species and areas that one might
suppose them to be a characteristic feature of the great fisheries. It is
significant, however, that fishery biologists are not in general agreement
as to the causes of these fluctuations.
Recently there have been major declines in the catches of some of
the sardines; declines which have caused great economic hardship and
have, at least in one instance, resulted in a greatly expanded research
effort (Anonymous, 1950). We refer especially to the Japanese land-
ings of Sardinops melanosticta, the North American landings of S. caeru-
lea, and the Portuguese landings of Sardina pilchardus. ‘These landings
are shown in Figure 1.
The North American data include landings in Canada and the
United States. Relatively small landings made in Mexico are also in-
cluded since 1940. It has been demonstrated (Schaefer, Sette and Marr,
1951) that from the inception of the fishery until 1942, the growth
of the fishery, as shown by the annual catches, followed a logistic curve
characteristic of the growth of many industries. Some of the deviations
about the curve are clearly related to economic conditions; the eco-
nomic depression of the early 1930's, for example, is reflected in the
reduced catches during that period. From 1934 until 1944 the annual
catch fluctuated around an average of about 550,000 metric tons. Fol-
lowing 1944 the catches have declined, in some seasons catastrophically
so, but with a short-lived partial recovery in 1949 and 1950. The basic
causes of this decline have not been completely elucidated, but the
major immediate causes include a series of smaller than average year-
classes and a probable shift in the distribution or migratory behavior
of the fish; the relation of an intensive fishery to these factors has not
* Published by permission of the Director, U.S. Fish and Wildlife Service.
183
184 EIGHTH PACIFIC SCIENCE CONGRESS
been determined to the satisfaction of all concerned (California Marine
Research Committee, in press).
The Japanese data include only the landings made in the Japanese
islands; they do not include landings in continental Asia. In some
years the latter were as large or larger than the Japanese landings. In
addition, it is not certain that the data include all Japanese landings,
nor that they refer entirely to the sardine. Nevertheless, and on a big-
ger scale, the curve of annual catches in the Japanese fishery is remark-
ably similar to that of the North American fishery. The peak catch
was obtained in the same year, but the decline started about two years
earlier. In 1951 there was a partial recovery.
The Portuguese data include only the landings made in poral
Obviously this fishery has never attained the magnitude of the other
two. Properly, this curve should include the catches of Sardina pilchar-
dus landed in all European and North African countries, but these data
are not available to us at the moment. The Portuguese landings are
therefore used as an example of the northeastern Atlantic sardine catch-
es. There is a peak, although not a pronounced one, in the Portuguese
catches occurring at about the same time as in the other two fisheries.
There is a decline occurring slightly later than in the North American
fishery. We understand that more recent seasons have shown a recovery
of the Portuguese fishery, but have thus far been unable to secure exact
data. :
These same catch data are also shown in Figure 2, but here, for
each fishery, the catch in each year has been expressed as a percentage
of the largest annual catch made in that fishery during the period re-
ported. This shows the relative fluctuations in the three fisheries with-
out respect to their absolute magnitudes. ‘The similarities already men-
tioned are even more strikingly shown in this figure, especially the rela-
tive magnitudes of the declines in catches and their close relation in
time, even though not simultaneous.
It is often inferred that when the catch of a particular species be-
comes less, the absolute size of the population is also reduced. This
is not necessarily true and it should be remembered that the data just
presented refer only to catches. The relation of these catches to the
size of the populations from which they were drawn is not known.
The reasons for a major decline in catch in any fishery must be
found among one or more of the following: (1) a decrease in the amount
of fishing effort expended per unit of time; (2) an increase in the
rate of natural mortality; (3) a decrease in the rate of recruitment
(i.e., a decrease in year-class size); or (4) a decrease in the availability
of the fish to the fishery, through a change in behavior or distribution.
WORLD-WIDE DECLINES IN SARDINE CATCHES 185
For the three sardine fisheries mentioned, we may safely rule out (1) as
a cause of the decline in the catches (barring war-caused interruptions
in fishing); one or more of the other three must be responsible.
In order to examine the possibility of the other causes being oper-
ative, various types of information are needed. In the case of natural
mortality rates, some estimates have been made, but they are not very
precise. In addition, for sardines, or practically any marine fish for that
matter, we have only general ideas about the various sources of natural
mortality and practically no ideas about how they operate. In any case,
they are not subject to modification by man, except as fishing mortality
may replace natural mortality.
Variations in rate of recruitment are probably one of the two major
causes of fluctuations in catch (the other being variations in availabil-
ity). Here again, we have only general ideas about the natural causes
of variation in year-class size and how these causes operate. So far as all
present evidence goes, such variations are natural. However, in theory
at least, the size of the spawning stock could influence the size of the
resulting year-classes. If the theory holds, Man could control year-class
size by controlling stock size, but this remains to be demonstrated in
practice. Data on relative year-class sizes as they appear in the catches
are of record, at least for the North American sardine fishery. What
we need, however, are data on year-class sizes as they exist in the popu-
lation.
Variations in the availability of fish to the fishery are, as indicated,
a major cause of fluctuations in catch. Accurate availability data are
extremely difficult to obtain and, in general, availability phenomena
are among the least understood in the field of fishery biology. For most
marine fisheries, however, it is difficult to see how they could be any-
thing but natural and not subject to control by Man.
So, the problem of the causes of these declines falls into two major
divisions: (1) What are the effects of Man’s activities and how do these
operate, and (2) What are the effects of natural phenomena and how
do these operate? Solution of these two sets of problems will require
not only additional observation, but also the development and testing
of theory.
Returning to our original question, if the declines in catches of
sardines were caused solely by Man, then the declines are indeed re-
lated. Such a relationship is not within the province of the fishery bi-
ologist, although the mechanics of its operation obviously must be.
On the other hand, if the declines are natural ones, how could they
be related? Such relationship could only be through a pandemic, which
has greatly increased the rate of natural mortality and for which, inci-
dentally, there is not much evidence, or, through some rather world-
186 EIGHTH PACIFIC SCIENCE CONGRESS
wide meteorological or oceanographic change. The latter possibility
has, in fact, already been suggested by Nair and Chidambaram (1951)
and by Uda (1952).
With the data at hand, it is not possible now to answer the ques-
tion posed by our title. Before the answer is attained, some, at least,
of the problems need to be more clearly formulated; data need to be
assembled, some of which are published in relatively obscure sources
or are not published at all; plans need to be laid and implemented;
and, finally, means must be found to promote greater exchange of ob-
servations and ideas among fishery biologists and oceanographers who
face these common problems. All of these objectives might be best
attained through the medium of international conferences.
LITERATURE CITED
Anonymous, 1950. Research projects examine fluctuating sardine popula-
tions. FAO, Fish. Bull., vol. III, no. 3, pp. 56-8.
California Marine Research Committee. In Press. Progress Report, 1 July
1952 to 30 June 1953.
Narr, R. VEDAPPAN and K. CHIDAMBARAM. 1951. A review of the Indian
oil sardine fishery. Proc. Nat. Inst. Sci. India, vol. XVII, no. 1, pp. 71-
85, 2 figs.
SCHAEFER, MILNER B., Oscar E. SETTE, and JOHN C. Marr. 1951. Growth
of the Pacific Coast pilchard fishery to 1942. U.S. Fish and Wildlife
Service, Res. Rept. 29, 31 pp., 6 figs.
UpA, MICHITAKA. 1952. On the relation between the variation of the im-
portant fisheries conditions and the oceanographical conditions in the
adjacent waters of Japan 1. Jour. Tokyo Univ. Fish., vol. 38, no. 3, pp.
363-389, 11 figs.
THOUSANDS OF METRIC TONS
WORLD-WIDE DECLINES IN SARDINE CATCHES 187
1,600
1.500
1,400}
1,300 }
1,200}
1,100 / \
babel
900
800
700 1
660 ‘
500 1
4350 ry PMA
fs
300 } hea Wy
100
Sy SR eV | ! kine fas l
19iD (915 i920 [225 1939 1935 1940 1945 1950
Fic. 1.—Total sardine catches for the United States (- ), Japan
(----- ), and Portugal (— ). Data obtained from the following sources:
United States-Calif. Fish and Game, vol. 34, no. 2, p. 83 (1948) and unpub-
lished information; Japan-U.S. Fish and Wildlife Service Fishery Leaflet
279, p. 83 (1948), and from personal communication from Dr. N. Nakai of
the Tokai Regional Fish. Res. Lab.; Portugal-Bull. Stat., Cons. Perm. Inucern.
VExplor. Mer, and unpublished information.
EIGHTH PACIFIC SCIENCE CONGRESS
188
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THE PRODUCTS OF THE SEA AND THEIR EXPLOITATION
AND UTILIZATION IN PAKISTAN
By M. R. KHAN
Central Fisheries Department
Government of Pakistan, Karachi, Pakistan
A comprehensive study of the Sea as a store-house of immense
mineral, vegetable, and animal wealth is beyond the scope of the pre-
sent paper. Only those products of the sea which are important from
the fisheries point of view and which occur in the waters off the coast
of Pakistan will be considered.
The demand for protein food in Pakistan is far in excess of the
present supply. Availability of grazing grounds and fodder imposes
limitations on the increased production of livestock in the country.
Faced with the problem of short protein food supply, Pakistan has
turned particular attention to her aquatic protein food resources.
Fish has a pronounced dietetic importance in Pakistan. During
1952 consumption of fish in Pakistan stood at 295.2 million pounds,
of which 242.8 million pounds were consumed in East Pakistan. Rice
and fish constitute the staple food of the population in East Pakistan
and no less than 90% of the people consume fish as a regular item of
diet. In West Pakistan consumption of fish is low except along the
coast and the riverine tracts. Annual per capita consumption of fish
in Pakistan has been estimated at 6.4 pounds. In East Pakistan in
certain localities where the supply is plentiful the per annual capita
consumption may be quite high.
Economically the importance of fishery to Pakistan is considerable.
It is estimated that there are over 200,000 fishermen families in the
country and as many as 800,000 subsist by fishing. In East Pakistan
alone there are 160,000 fishermen families and over 650,000 make a
living out of fishing. These figures include fishermen engaged in fresh
water fisheries. Furthermore, the economy of Pakistan is basically
agrarian. It is desirable that the country’s agriculture be supplemented
by a well-organized fisheries industry.
THE RESOURCES
Pakistan has a total of 700 miles of coast line, 500 miles in West
Pakistan and 200 miles in East Pakistan. The coast of West Pakistan
is bounded by 23°-40’N to 25°-30’N latitudes and 61°-40’E to 68°-10’E
189
190 EIGHTH PACIFIC SCIENCE CONGRESS
longitudes. The coast of East Pakistan lies between 20°-50’N to 22°-
5O’N latitudes and 89°-00’E to 92°-20’E longitudes. The coast of West
Pakistan falls into two distinct divisions: the Mekran coast and the
Sind coast. The Mekran coast extends over a length of 350 miles from
Hub River, about 20 miles West of Karachi, to Gwatar Bay on the
Iranian Border. The coast has a number of bays and is interrupted
by two breakwaters. ‘The most important breakwater on this coast
known as Miani Hor lies about 60 miles West of Karachi. It is approx-
imately 40 miles long and at places 10 miles broad. There are no peren-
nial rivers on the coast; all the rivers and streams remain dry except
for a few days of occasional rain brought in by the southwest mon-
soons during summer and northeast cyclones during winter. The total
rainfall on the coast is less than 3 inches a year. Hills, some of which
rise up to 3500 feet, are bleak and barren, and run parallel to the
coast sloping steeply into the sea.
The Sind coast extends from Karachi to Sir Creek over a length
of 180 miles, and is marked by a network of creeks which extend to a
considerable distance inland. ‘These creeks have been formed by the
Indus and other rivers as they change course from time to time. Hills
are noticeably absent on this coast.
The coast of East Pakistan is broken by the mouths of the Ganges,
the Brahmaputra and numerous other rivers. “The 200-mile-long coast
is plain except for a fringe of hills on the southeast. These hills are
a continuation of the northeastern wing of the Himalayan ranges.
Beyond the territorial limits of Pakistan lie the waters of the Bay
of Bengal in the east and the waters of the Arabian Sea in the west.
The floor of the Bay slopes slowly from the shores and the 100-fathom
line lies 100 miles from the coast. “The bottom topography is smooth
except for a submarine canyon directed southward from the mouth of
Pusur river. The ocean bottom is covered with thick layers of terrig-
enous ooze. ‘The salinity, turbidity and other physical, chemical and
biological features of the waters of the Bay are greatly influenced by
the heavy discharge of the Ganges, the Brahmaputra and other rivers.
The wind movement and revolution of the earth give a rotary move-
ment to the waters of the Bay.
In contrast to the Bay of Bengal, the Arabian Sea is open and its
waters are subject to influences of the South-East current, of current
movements originating in the Mozambique channel and the rotary move-
ment in the Arabian Sea. ‘These movements undoubtedly influence
the physical, chemical and biological properties of waters of the Ara-
bian Sea. ‘The discharge of the Indus also exerts pronounced influence
on the character of the water in that part of the Arabian Sea which
PRODUCTS OF THE SEA—EXPLOITATION AND UTILIZATION 191
lies off the Indus estuary. The continental shelf area of the Arabian
Sea is restricted. It is about 100 miles only off the Indus estuary and
shrinks to about 30 miles off the Mekran Coast. The edge of the con-
tinental shelf lying at the 100-fathom line falls steeply into deep water.
A submarine canyon cuts the shelf opposite the Indus estuary. The
area adjacent to this is subject to a considerable amount of silting.
Fauna: The fauna and flora of these waters are fairly known from
a systematic point of view. Schools of ‘Sczaena, Tuna, Polynemus and
Pristtipoma’ have been observed to be present in seasonal pattern on
the surface of the off-shore waters. In mid-waters ‘Cybium and Elas-
mobranchs’ are present, whilst the fauna of the bottom waters com-
prise ‘Synaptura, Cynoglossus, Lutianus, and Elasmobranchs’. The in-
shore fauna which are endemic and which share some elements of the
off-shore, brackish, and fresh-water fauna, consist of stocks of ‘Mugzl,
Sillago, Chrysophrys, Gerres and Lutianus’ in addition to a very sub-
stantial fauna of ‘Penaeidae.’ The brackish water areas which are ex-
tensive, totalling about 7,500 square miles, include a vast network of
waterways which are inhabited by a varied fauna of ‘Mullets, Perches,
Herrings’ and an extensive stock of oysters. “The brackish water con-
ditions which penetrate the main river course influence to a great extent
the up-stream ascent of the very important fish Hilsa or Palla—‘Hilsa
ilisha’.
Beyond the faunistic lists, knowledge of the resources is seriously
limited. Whilst the general distribution of a few of the more important
species is known, the precise distribution of these, and the variation of
the limits of distribution from season to season, is not known. Little
information is available on the life history in terms of spawning sea-
sons and habits, feeding habits, and migratory movements of these
species. There is no record of any estimate having been attempted,
of the natural abundance of any species of the area. Certain species
are known to be more abundant than others; at least, greater catches
are taken by the fishermen. But whether these catches approach or
exceed the proper limits which the natural stocks can sustain, is not
known.
‘THE INDUSTRY
The primary phase of the fishing industry consists of the following
major divisions:
(1) Capture operations in the off-shore waters,
(2) Capture operations in the brackish waters and open waterways
of the Gangetic and Indus delta and
(3) Culture operations in the estuarine areas.
192 EIGHTH PACIFIC SCIENCE CONGRESS
Culture operations in East Pakistan chiefly take place in the estua-
rine areas. ‘The operations which concentrate on mullets, perches and
prawns are simple and involve basically the construction and main-
tenance of bunds, the control of water movement and, where necessary,
some feeding. It is estimated that over 20,000 persons are engaged in
these culture operations.
Fishing by capture operations is carried out in surface, middle, and
bottom waters. ‘These operations at present are confined at 8-10 miles
from the shore and the 10-fathom line. While these operations are
thus confined they are also restricted in their along-shore extent. The
fishermen do not carry any navigational equipments nor do they have
any knowledge of the science of navigation. It is impossible for them
to go beyond the visibility of the shore. 5
Fishing Season: During the months of June to August the south-
west monsoons are in full swing and there are heavy swells in the sea
making it impossible for any fishing operations to be conducted in the
open sea. Limited fishing is carried out in the protected waters of the
estuarine areas. ‘Throughout the rest of the year fishing is conducted
with varying degrees of intensity in all waters.
Fishermen: The number of fishermen engaged in marine fishing
in Pakistan has been estimated at 85,000. In addition to active fisher-
men there are those concerned in handling and transport, processing
and preservation, the middlemen and merchants, and market operatives.
The fishermen live in important port towns and in isolated villages
along the coast. During seasons for particular fisheries, temporary col-
onies may also be set up. ‘The villages are built on the sandy and un-
protected beaches; the huts and tenements are made of mangrove and
bamboo sticks, and weed mats.
Fishing is essentially a whole-time occupation for the majority of
the fishing group. During the monsoons when no fishing can be con-
ducted in the disturbed sea, the fishermen engage themselves in making
and mending nets and repairing boats and fishing in protected waters.
The fishermen are generally illiterate and unskilled. Their knowl-
edge of the behaviour of fish, of the weather, currents, bottom and of
the operation of crafts and gears is seriously limited. ‘They are also very
much impoverished; their annual money income is probably, on the
average, 400-500 rupees (125-150 U.S. dollars) per head.
Crafts and Gears: The crafts are plank-built, wind-driven vessels
ranging from 15—60 feet in length and 14 to 50 tons in capacity. They
are not decked in and provide no living accommodation even in the
larger crafts. “The storage of fish is provided merely by wooden boxes
and holds without any ice or refrigeration. Smaller crafts carry crew
PRODUCTS OF THE SEA—EXPLOITATION AND UTILIZATION 193
of three to four and operate on single day journeys. Larger crafts
carry from eight to ten persons and stay at sea for four to five days.
Sometimes larger vessels stay away from ports for longer periods. In
such cases the catch is salted on board and the vessels move every third
or fourth day to convenient spots on the shore for drying the salted
fish.
In addition to the local operations with country crafts, the Gov-
ernment’s experimental trawler ‘ALA’ has been operating in the waters
off the coast of West Pakistan. ‘ALA’ is 80 feet long and has a gross
tonnage of 81.24. She has a steel hull, and a Ruston diesel engine of
150 B.H.P. The fish hold is refrigerated and has a capacity of 30 tons.
The trawler employs a Peter Carey trawl, 75 feet long. The operations
of the trawler has not extended beyond the 30-fathom line.
The Trawler has made a number of trips. The results so far have
not been encouraging. Although the tropical waters are known not to
be rich in bottom fauna, the possibilities of trawling in these waters
cannot be ascertained until after exhaustive surveys. “The operations
of ‘ALA’ are limited both in seasonal and geographical co-ordinates for
the purpose of any conclusions.
The gears commonly employed in Pakistan are (1) fixed or stake
nets, (2) boat seines, (3) beach seines, (4) drift and gill nets, (5) cast
nets, (6) traps and weirs, and (7) hooks and lines. Non-searching type
of a gear, e.g. stake nets, drift and gill nets, are numerically predom-
inant and their total catch is more than that of the searching gear. Of
the latter group, the boat seines are most important. These nets catch
sardines, herrings, drums, croakers and threadfins, depending on size
and mesh.
The nets are prepared by hand, using mostly cotton, occasionally
hemp, and nylon whenever it is available. Net preservation practices
consist of their treatment with lime and occasionally with extracts of
some indigenous barks.
The crafts and gears are not mechanized. ‘This severely restricts
the fishing operations in their range along seasonal and geographical
co-ordinates.
Capital: A reliable estimate of capital invested in the primary
industry is not available yet. Preliminary figures place it anywhere from
10-12 million rupees (3—4 million U.S. dollars). Of this nearly 55 per-
cent is invested in crafts and the rest is invested in gears and as recur-
ring expenditure. Capital in Pakistan is noted for its shyness; on the
other hand, the manipulations of the middlemen place impediments to
the flow of fresh capital in the fisheries industry.
Economics and organisation: The number of owner-operators who
work alone as single units is negligible. Some outfits are operated by
194 EIGHTH PACIFIC SCIENCE CONGRESS
the crew; the owner of the outfit generally has a share in the operations,
even if only their supervision. The people who operate the gear do so
cn a share basis. As is usual elsewhere, the boat and gear used in share
fishing, count equally with the operatives in drawing a share. In some
cases of sharing of earnings the owner makes advances to the crew and
undertakes some responsibility for food, either providing it against
shares, or guaranteeing the necessary credit. Under such circumstances
an arrangement is made by which the fish must be sold to the owner
or his agent.
Quite frequently the crew are employed on wage basis. Such crew
are provided with gear and are completely ‘found.’ In East Pakistan the
owners of boats and gears engage their agents to assemble parties, of
up to 200 or more, of fishermen, curers and others; the workers of the
party are engaged on wage basis whilst the agents are contracted to
take the catch to the owners, of boats and gears, to sell on an agreed
basis. ‘The owners supply food and advance money.
Amount of Production: Annual production is estimated to be in
the order of 100,000 tons, wet landed weight of fish. The bulk of this
is landed in East Pakistan. Wide variations in the catch exist in dif-
ferent localities, seasons, and in species. Variations of this kind are
characteristic of the fishery and have considerable effects on it in every
way.
The catch in East Pakistan is composed of 30% Clupeoids, 25%
Crustaceans, 15% Bombay ducks and Hairtails, 7% Elasmobranchs, and
11°% miscellaneous fish. In West Pakistan the catch consists of 25.5%
of Elasmobranchs, 18.5% Perches, 18.0% Crustaceans, 11.5% Mackerels,
10.5% Clupeoids, and 16% miscellaneous fish. In addition there are
3-5 thousand dozens of oysters and clams produced each year.
In the absence of any reliable data regarding production by units
of time, of area, the number of crafts and gear, the number of men who
fish, it is not possible to measure accurately the total amount of effort
and catch per unit effort.
SECONDARY INDUSTRY
The secondary phase of the industry leaves much to be desired.
The equipment for handling, transport, marketing and distribution are
inadequate and inefficient, this being especially true of ice-making
equipment. Processing methods are also not satisfactory and yield prod-
ucts of inferior quality.
Estimates of production passing through various channels of dis-
posal are extremely variable. It is held that of the total production in
West Pakistan approximately one third is handled and consumed fresh
PRODUCTS OF THE SEA—EXPLOITATION AND UTILIZATION 195
and two thirds processed. In East Pakistan roughly 80 per cent is con-
sumed fresh. The products of processing are cured fish, cured prawns,
fish fertilizer, fish meal, shark fins, isinglass and liver oil.
Handling and Transport: Of the fresh fish the greater proportion
is handled with primitive apparatus and without any means of pre-
servation. The catch generally must suffer the exigencies of inefficient
transport, careless handling and inadequate use of ice.
Transport facilities are varied and primitive. Use is made of head-
loads, bicycles, animal carts and some motor transport. Some use is
also made of water transport. In estuarine areas salt is used if the fish
is to travel more than 50 miles. The fish rarely arrives at the market
and less often reaches the consumer in good condition.
Processing: Fish is commonly processed by (1) sun-drying, (2)
salting, (3) salting and sun-drying, and (4) smoking. Salting and sub-
sequent sun-drying is most extensively used in West Pakistan whilst in
East Pakistan sun-drying and wet-salting are equally important. Smok-
ing, which is of minor importance, is employed only in East Pakistan.
Fertilizers are produced by sun-drying the fish or fish offals and subse-
quently crushing them. Shark livers are heated in pans by direct fire
except in the case of a small quantity of medicinal liver oil produced
in East Pakistan by the Provincial Directorate of Fisheries.
The curing yards are inefficient. “They provide no elevated plat-
form for dressing fish and most of all, supply of running water in these
curing yards is tetally absent. Brining tanks where available are built-
in and cannot be drained out.
Fish are dried on bare ground or on woven mats. Wooden racks
are uncommon.
The smoking kiln is an open pit where local wood or sawdust is
allowed to smoulder. No care is taken in the choice of wood or in
regulating the rate of burning.
Salt employed for curing is mixed with sand and mud and contains
high amounts of sulphates, calcium, and magnesium.
The finished product is generally of poor quality. Unsatisfactory
colour and texture, off-flavour and signs of rancidity are noticeable
in the cured fish. Considerable damage is caused to the product dur-
ing storage as the product is left under inadequate and unsatisfactory
storage conditions for long periods.
Marketing and Distribution: Fish supplies are accumulated at
various collection centres. These centres do not have established market
places, nor are they hygienic or efficient in any sense of these words;
many of the operations take place on bare ground. In general, the ‘fish
market’ consists of little more than some space and perhaps a few
benches allotted in the general market for the selling of fish. In Karachi,
196 EIGHTH PACIFIC SCIENCE CONGRESS
however, a cement floored building is used as a wholesale market. This
building does not have sufficient space for handling the total landing
nor is it supplied with running water.
The fisherman delivers his catch at the point of landing to an
agent who may auction it on his behalf to wholesalers, retailers and fish
curers or may buy it from the fishermen where financial arrangement
exists between the agent and fishermen. The wholesalers in turn sell
the fish to the retailers who sell it to the consumers. ‘The fish curers
mainly export their products. The agent who first receives the fish
from the fishermen is the individual who provides finance to the fisher-
men. Apart from the collection of sales tax under certain circumstances
the Government takes no part whatsoever in this marketing process at
any stage.
Trade: Although there is an overall deficit in the country, in re-
stricted areas there is a surplus in fish supply which is particularly due
to inadequate facilities of handling and transport. Pakistan exports
some of this localised surplus. During 1952 over 10,000 tons of fresh
fish were exported to India. The main bulk of it consisted of fresh-
water fish and came from East Pakistan. The total export of processed
fish stood at 9,635 tons. In addition, during the same year Pakistan ex-
ported over 2,000 tons of fish fertilizers, 160 tons of shark fins and fish
maws. As against the export, 460 tons of processed fish, 520 tons of
fish oils and 173,500 pounds of vitaminous fish oils are shown as having
been imported during 1952. The total value of the export trade during
1952 stood at 12,300,000 rupees (3.2 million U.S. dollars) whilst that
of the import trade during the same year stood at 1,527,000 rupees
(500,000 U.S. dollars) .
Socio-Economics: “The economic problems of fishermen in Pakistan
concern his methods of production, purchase of domestic and production
requirements, provision of credit, and the sale of his produce. The craft
and gear and other equipment which the fisherman uses are primitive,
inefficient and wasteful though effective in their own way. The middle-
men to whom, in many cases, the catch is sold in advance, generally,
supply the fishermen with his domestic and production requirements,
and with other credit accommodation that he may need. He is compelled
more often than not by circumstances of trade to buy dear and sell cheap
and thus the fisherman sinks irretrievably into debts. Belonging to an
economically and socially backward community, ignorant and unedu-
cated, he has generally neither the will nor the means of organising
himself for self-emancipation.
Although the fishermen are impoverished and illiterate, these de-
ficiencies of wealth and education may not be presumed to apply to
PRODUCTS OF THE SEA—EXPLOITATION AND UTILIZATION 197
their technical qualifications. The Pakistani fishermen are competent,
skilled sailors, proficient in the use of their traditional equipment. There
seems to be no reason to doubt that these men at least will be capable
of learning the use of new equipment and the operation of new craft.
The fishermen are unable to attempt on their own behalf develop-
ment of their equipment and operations. This situation may be attri-
buted to the combined effects of the improvidence of the fishermen, the
inefficiency of the equipments, and the manipulation of the middlemen.
Certain external influences, such as the demand for fish and the purchas-
ing power of the consuming public, also have a bearing on the situation.
There exist considerable differences of taste among people in different
parts of the country; coupled with this is the inadequate marketing
system, which would seem to make the demand for fish uncertain and
weak.
CONCLUSIONS AND RECOMMENDATIONS
The status of fisheries in Pakistan is low. The resources are capable
of yielding a much greater supply of fish than they do at present. The
procurement of that increase will require in some cases the introduction
of new methods and in others an intensification and improvement of
existing methods. Such changes in methods imply comparable changes
in the craft and gear, and in certain cases will require adjustment of
fishermen. Undoubtedly these changes will demand substantial re-
orientation of the secondary phase of the industry in order that it may
be capable of handling the increased supply and giving a better quality
of service.
Increased production, adequate distribution and disposal of the
produce are the chief tasks in the development of Pakistan fisheries.
Extension of the fishing grounds, improvement and increased employ-
ment of gear, and mechanization of the craft will enhatice production.
Construction of markets at important fish landing centres, provision of
sufficient ice and cold storage, railway refrigerated cars and trucks, and
of various processing facilities will ensure proper distribution and dis-
posal of the produce.
Well-organised central and provincial Fisheries Departments are
formulating schemes for the development of the fisheries resources of
the country. As a member Pakistan has received help in this task from
the Food and Agriculture Organisation of the United Nations. A
thorough survey of the resources has been undertaken in the waters off
the coast of Karachi where already a number of good fishing grounds
have been located. A scheme for the construction of a fish harbour at
Karachi has been approved by the Government of Pakistan. This har-
198 EIGHTH PACIFIC SCIENCE CONGRESS
bour is intended to provide all modern facilities for berthing of fishing
boats, modern curing and other processing facilities for fish and fish
products, ice and cold storage, and wholesale marketing of marine fish.
Similar schemes for mechanisation of craft and gear, refrigerated trans-
port, refrigerated markets and processing plants in other parts of the
country are in their final form.
Private enterprise is also stepping forward, although rather slowly.
A fish meal plant will go into production within the next month or
two; another plant for freezing shrimps is expected to start operation
before the end of 1953; and keen interest is being displayed by several
concerns in the possibilities of fishing with mechanised craft and gear,
of canning fish, particularly of shrimps, and producing vitaminous shark
liver oil.
Implementation of the proposed development measures in fisheries
will, no doubt, require considerable capital investment. On the other
hand, the economic condition of the fishermen does not make it possible
for them to invest in the development of the industry. Except a minor
fraction, the capital so far invested has come from Government account
and from the Colombo Plan and the U.S. Technical Co-operation funds.
Recently Sweden has also offered some aid. Although pilot scale
development plans may seem advisable at present some well-integrated
overall policy will induce expeditions and increased flow of private
capital into the fisheries industry. Effective efforts should be made to
improve the economic condition of the fishermen so that they may them-
selves be in a position to invest in the development of the industry. In
this respect the fishermen should be organized into cooperative societies.
These societies should provide credits and link credits with purchase of
necessities of the industry and of life on the one hand and the sale of
the produce on the other.
Viewed in the general context of the economic and nutritional
problems of Pakistan, and of the world food situation, the need for the
development of fisheries in Pakistan cannot be over-emphasised. The
development plans should be co-ordinated and integrated into an over-
all policy so that the development of the industry may serve the interests
of the producers, the middlemen and the consumers alike.
BIBLIOGRAPHY
AHMED, M. Hilsa Fisheries in Sind. Agri. Pak., Vol. III, No. 1 & 2, 1952.
KESTEVEN, G. L. Report on the Fisheries of Pakistan, Ministry of Food and
Agriculture, Government of Pakistan, Karachi, 1950.
and S. W. Linc. Report on the Fisheries of East Pakistan. (Ms.)
1951.
EXPLOITATIONAND UTILIZATION 199
PRODUCTS OF THE SEA
KHAN, M. R. A case for Pakistan Fisheries. Econ. Comm., Vol. I, No. 8,
1952.
Synthetic Vitamin A and the Future of Fish Liver Oil Industry,
particularly in Pakistan. lAg7ri. Pak., Vol. IV, No. 1, 1953.
Possibilities of Fish Meal Industry in Pakistan. (Ms.) 1952.
and M. AHMED. Report on the Baluchistan Marine Fisheries.
(Ms.) 1952.
QuRESHI, M. R. Prospects of Marine Fisheries of West Pakistan. Bull. Kar.
Geog. Soc., Vol. II, 1950.
Marine Fisheries of Pakistan with a view on Trawling. Proc.
I.P.F.C., April, 1950.
Fishes of Mekran Coast. Agri. Pak., Vol. II, No. 4, 1952.
and M. AHMED. Fish Trade in Pakistan. Agri. Pak., Vol. III,
No. 3, 1952.
SOME FACTORS BEARING ON THE UTILIZATION OF
MARINE PRODUCTS OF THE WEST
COAST OF CANADA
By NEAL M. CarTER
Pacific Fisheries Experimental Station
Fisheries Research Board of Canada
Vancouver, B.C., Canada
Fish and shellfish have been a food of man from prehistoric times.
Remains of fish bones and marine shells exist in the débris of Pleistocene
period European cave dwellers, and the kitchen middens of Recent
period Indians of the coast of British Columbia are composed principally
of clam shells with a few fish bones. Because of the ease with which
they can be secured, shellfish probably attracted prehistoric man’s at-
tention before he recognized their edibility. Perhaps his first taste of
fish followed seeing some animal or bird devouring a fish it had caught;
seeking more of this delicate food, no doubt his first efforts at ‘‘fishing”’
consisted of picking up dead or stranded fish in shallow streams, on the
beach, or in tidal pools. Soon (maybe a thousand years later) his grow-
ing inventiveness developed the first true fishing methods. One of the
earliest must have been the placing of a barrier of stones, stakes or
branches in a shallow stream, or a circlet of rocks on a tidal beach in
imitation of natural tidal pools. “The writer has seen such artificial tidal
pools, constructed in modern times, still in use by the native British
Columbia Indians not more than a hundred miles up the coast from
Vancouver. ‘The chronology of the invention of such fixed barriers, in
relation to the invention of transportable fishing gear, is lost in pre-
historic antiquity. Examples of fish spears have been found in prehis-
toric caves; nets and lines may have been used contemporarily but owing
to their more perishable nature traces of them have vanished. Pictorial
records of fishing nets antedate those of fish spears, and it is known that
the spear, net, line, and rod flourished synchronously as early as the
XUth Egyptian Dynasty. ‘The earliest picture of angling and hand
lining is dated at about 2000 B.C.
Once adequate methods of capturing fish for food became developed,
it 1s interesting to note the very great esteem accorded to fish as an article
of commerce and diet in early historical times. ‘The Bible alone con-
tains some 80 references to fishing, fishermen, fish and other aquatic
products, though curiously enough in no instance is any kind of fish
200
UTILIZATION OF MARINE PRODUCTS OF CANADA 201
mentioned by name. It has been facetiously suggested that there had
not yet been time after the Flood to assign, names to the fishes, for
because of the very nature of that catastrophe there was no neces-
sity to make provision for the fishes when cataloging “every living thing
of all flesh, two of every sort . . . male and female” as they entered the
Ark. In the Indian legend of the Flood it was a fish, not a Deity, that
gave warning of the coming deluge; a fish, not a dove returning with an
olive leaf, signaled the recession of the waters and drew the ark-like
vessel to rest on a northern mountain.
Among the many records of the popularity of fish the Bible ac-
count of the miracle of the loaves and fishes is well known. Fish played
an important role in the food of the early Egyptians; King Rameses III
was in the habit of presenting many thousands of fish to the temples for
the benefit of the priests’ employees and the populace, and Rameses IV
maintained “officers of the Court Fishermen” whose duty it was to
provide large quantities of fish for the monarch, his entourage and servy-
ants. Carefully mummified fish bearing a royal cartouche have been
found, symbolizing the esteem bestowed upon them. ‘The Egyptian city
Latopolis was named in honour of the fish Lates niloticus. But it was
in the heyday of the Greeks and Romans that fishes really came into
their own as luxuries. Seas and rivers were exploited far and wide for
their delicacies. Mullet, sturgeon and turbot commanded fabulous prices
for the epicurian table. Pliny records that although mullet weighing
under two pounds were plentiful and cheap, a large one was worth
8000 nummi (about $300), the value of nine bulls. ‘The Greek come-
dians lamented that fish cost their weight in money, as was the case also
in Rome. Martial upbraided a glutton who sold a slave for about $50
to purchase a dinner, then complained of its lack of variety because near-
ly all the money was spent for one mullet. At a Greek Attic feast,
thirty-two kinds of fish were served; at a banquet given by the Roman
emperor Vitellius in honour of his brother no less than 2000 choice
fishes were served. A treatise of ten volumes on recipes for new dishes,
attributed to Apicius, describes many sauces for fish, one of which calls
for twenty-five ingredients. Some Roman nobles varied the custom of
taking a cognomen from the name of a victorious battle by assuming
a name derived from their favorite fish, e.g., Licinius Muraena, Sergius
Aurata. Among the Greeks, Diogenes the Cynic died from the eager
haste with which he devoured a raw polypus, and Philoxenus the Poet
after dressing, cooking, and eating all but the head of a 36-inch polypus
was warned by his physician that he had but six hours to live. Much
later, King Henry I of England died from overindulging in his favourite
dish of lampreys, a primitive fish at present much despised in Canada
202 EIGHTH PACIFIC SCIENCE CONGRESS
and the United States because of its current depredations on the com-
mercial fishes of the Great Lakes.
What precautions were taken in these early days to maintain the
delectable qualities of freshly caught fishery products? History tells us
that much of the fish was net cured in any way, and the need for keep-
ing fish cool was already appreciated. Nehemiah, Governor of Judaea,
complained in the Biblical book of his name about the sale of food-
stuffs in Jerusalem on the Sabbath, including fish brought by the men
of Tyre from the shores of the Mediterranean some 35 miles away; he
caused the gates of Jerusalem to be closed to such commerce over the
Sabbath, but later it was allowed that a special gate, called the “fish
gate’ should remain open so that fish could be sold before it would
spoil. In Greece, runners were sent up the slopes of 8060-foot Mt. Par-
nassus to collect snow for preserving fresh oysters for banquets in near-
by Athens. The Romans constructed huge vivaria or fish ponds in which
to keep fish alive during warm weather until required for the table.
Lucius Philippus had a tunnel pierced through a mountain in order
to bring cool sea water to his vivarium; Hortensius Varro placed more
importance on the coolness of the water in his vivarium than on the
coolness of a draught of water for a fevered friend. Archimedes is
credited with planning the construction of a large live-well, made of
planks lined with lead, in the bow of one of the large vessels plying
between Egypt and Sicily for the corn trade and carrying live fish in
this well in which the salt water was constantly renewed by hand pump-
ing. In early Egypt fish for the fresh trade were usually dressed on the
boat and quickly dispatched to market. By New Testament times fresh
fish were roasted, baked, or boiled; eggs were sometimes combined with
the boiled type. But what of the fish that could not be transported
fresh to market? The Egyptians were familiar with the process of split-
ting and salting then drying in the sun, and such salted fish, as well as
pickled fish, were exported in baskets or barrels certainly as far as
Palestine.
‘Turning now from ancient times in the Old World to more modern
times in the West Coast of Canada, the native Indians of this coast
prior to the coming of the white man had developed not only their
clam fishery attested by the huge clam shell middens already mentioned,
but also a considerable adeptness in catching fish, particularly salmon
and eulachons. ‘To preserve these fish for use out of season, salmon
were cleaned, split, and subjected to a combined drying and smoking
process in crude smoke houses; because the salmon ascends rivers to
spawn hundreds of miles inland, many Interior tribes had access to this
fish, though it lacked fat by the time it reached distant spawning beds.
UTILIZATION OF MARINE PRODUCTS OF CANADA 203
Eulachons, a small, marine, smelt-like fish taken principally only in the
river estuaries, were hung from the head on large vertical racks for
open-air drying and when dried were so oily that they could be ignited
and used as candles. Probably the earliest fishery by-product industry
in what is now British Columbia arose from the craving of both Coastal
and Interior natives for fish oil as a cooking fat and as a protective or
ceremonial lotion for the skin and hair. The fish were allowed to under-
go some decomposition to partially free the oil and were then boiled in
wooden tanks, the liberated oil was floated and skimmed off and stored
in animal skins or (after congealing) in closely woven jar-shaped bas-
kets. Trade in this oil with Interior tribes developed the well-trodden
“grease trails’ over the lowest mountain passes and through the most.
suitable valleys into direct routes that would be a credit to a modern
road engineer. These native fishing and preservation methods still per-
sist on some parts of the coast, though the modern Indian has been
known to visit an Interior cousin via his own automobile or a com-
mercial airline, taking a token of eulachon grease either upon or with
him, to the olfactory discomfort of any white passengers.
With the settlement of Canada’s west coast by the white man, fol-
lowed in 1858 by the establishment of the Colony (now Province) of
British Columbia, a much greater exploitation of the coast’s fishery
resources began. Commercial salting of Fraser River salmon com-
menced as early as 1829 and by 1835 some 3500 barrels were being ex-
ported annually, principally to the Hawaiian Islands; salmon canning
on the Fraser River began in 1870; fisheries for herring, trout, sturgeon,
halibut, flatfish, dogfish, eulachon, seals and porpoises were reported by
1875. It is not the purpose of this paper to summarize the subsequent
growth of British Columbia’s fisheries or to describe the nature of the
raw materials and the many processing methods used to turn these into
finished products and by-products for local consumption, trade with the
rest of Canada, or export. Government fisheries statistics commenced
in 1876 are available for such purposes. Suffice it to state that the
marketed value of British Columbia’s fisheries in 1911 was $13,677,125,
and in 1951 was $85,500,000, while the marketed values of the whole
of Canada’s fisheries for the same years were $34,667,872 and $200,125,000.
British Columbia therefore contributes a very substantial portion to the
total fisheries production of Canada, which exports more fish than it
imports because it produces more fish than its population desires for
their own consumption. ‘The 13.7 pounds per capita per annum (1951)
consumption of fish by Canadians is quite low in comparison with that
of most other countries, even some not so richly endowed with fisheries
of their own.
204 EIGHTH PACIFIC SCIENCE CONGRESS
British Columbian and other Canadian fisheries, if encouraged by an
increased desire on the part of Canadians to eat more fish per capita per
annum, could meet this incentive and still continue to supply Canada’s
export markets with the kinds of Canadian fish products which the
peoples of some other countries appear to appreciate more than do
Canadians themselves. Why is there this lack of incentive of Canadians
to appreciate and eat their own fish to a greater extent?
Apart from economic considerations such as the living standards of
certain classes of Canada’s population, and the present still-increasing
costs of labour and materials that contribute to the retail cost not only
of fish products but of other foods as well, some of the reasons for
Canada’s low fish consumption are:
(a) Living standards, including those for food, are relatively high;
a great variety of raw and processed foods are available for competing
with fish from the standpoint of the Canadian’s purse and palate. Fish
must be of high quality that will enjoy the confidence of the consumer
before it will compete more successfully with other foods, particularly
other animal products such as meat, fowl, and dairy products.
(b) Unfortunately, some past experiences of the Canadian adult
generation with quality of fish products, particularly fresh and frozen,
have not been too happy, and these impressions have been heightened
by reminiscences of the previous generation concerning still unhappier
experiences. Even in present-day Canadian and American popular
literature including comic strips and cartoons, one sees the expression
“something fishy about that” as synonymous with an undesirable state
of affairs. “To draw a red herring across a trail” is still used figuratively
to express the original literal idea that a somewhat rancid salted herring
would effectively baffle bloodhounds tracking a scent. A cartoon or
comic strip character carrying a parcel of fish (usually with wavy lines
representing odour arising from it) almost always encounters some em-
barrassing situation, often resulting in the fish eventually reposing in a
garbage can. Such allusions do not enhance the public’s desire for fish.
Unlike the enthusiasm of the ancients already mentioned, reference to
fish is practically never used in America in a euphemistic sense. Meat,
on the other hand, is frequently used in a laudatory and even euphem-
istic manner, e.g., “the meat of a subject” for the essence or truth of
the subject; the word “meat” for the edible portion of even a vegetable
product, such as “nut meats.” Fish flesh is very seldom referred to as
“meat.”
(c) Fishery products in Canada, with the exception of canned
salmon, canned herring and dry salt herring from British Columbia,
and a few other products of the fisheries from the Central and Atlantic
UTILIZATION OF MARINE PRODUCTS OF CANADA 205
Coast, are not subject to Federal Government inspection. Provincial
sanitary regulations for fish processing plants apply in most Provinces,
but do not always cover the products themselves. Voluntary inspection
control is exercised by many processing firms, much to their credit, but
unfortunately not by all to the same degree. This has an adverse bear-
ing on the desirable confidence of the consumer of fishery products,
mentioned under (a) above. On the other hand, meat products in
Canada are processed under careful Federal Government control, and
milk products receive considerable Federal or Provincial attention.
(d) Because of the bounteousness of many fishery harvests, not only
in British Columbia but in other parts of Canada, there is an un-
fortunate tendency in times of glut to handle the raw product and its
processing in a careless manner suggestive of the handling of cordwood,
coal, or some other non-perishable material despite the fact that tish and
shellfish flesh is more perishable than that of meat or fowl, which re-
ceives more careful attention. It is true that in times of extreme glut
some of the raw material is diverted to manufacture of products such
as fish meal and oil not intended for human consumption. However,
there is ample advice available from technological sources to show the
way towards better handling of fishery products during every stage from
the time of catch to display for the ultimate consumer. Not all of this
advice has been heeded.
(e) No matter how good may be the quality of a fishery product,
particularly raw, fresh or frozen fish, there exists a certain aversion on
the part of many ultimate consumers to the odours and other unpleasant-
nesses of preparing the product for the table. Many housewives complain
of the odour of cooking fish, and families may enjoy fish cooked in a
restaurant more than they would at home, in order to avoid this in-
convenience. However, most people do not eat in a restaurant as often
as at home. This aversion to the odours of cooking fish may be a matter
of opinion influenced by hearsay, for many families cheerfully accept
the somewhat faecal odour of cooking cauliflower.
(f) Some people just do not like fish. Vegetarians are included in
this group.
To offset some of the above reasons for lack of appreciation of fish
in Canada, it must be stated that while Canada has lagged somewhat
behind some countries, particularly certain Scandinavian countries, in
rigorous control over the quality of its fisheries products for both home
consumption and export, it is well ahead of many other countries in
this respect. Fisheries technological stations were instituted by the
Biological Board of Canada (now the Fisheries Research Board ot
Canada) at Halifax on the Atlantic coast in 1925, at Prince Rupert on
206 EIGHTH PACIFIC SCIENCE CONGRESS
the Pacific coast in 1926 (later moved to Vancouver in 1942), and on the
Gaspé coast of Quebec in 1936. These stations, with the assistance of
the Federal Department of Fisheries and the collaboration of Canadian
fish processers, have gone far in the investigation of the basic principles
underlying the utilizations of fishery products, and the applications of
these principles.
The writer would draw attention, however, to the fact that not only
some of the principles known to the Ancients, but also those developed
through modern scientific research directed towards the handling and
processing of fishery products in many countries, are sometimes over-
looked or find delayed and slow application in the very countries where
the principles were or are being evolved. Mention has been made of
the opening of a fish gate on the Sabbath to allow fish to be sold in
Jerusalem before it might spoil on further holding; in this so-called
enlightened age there are still cases where fresh fish are held over for
later sale to the detriment of its quality because of man’s cupidity,
where a hint from the cited solution might improve matters. ‘The ex-
ample of the Athenians in securing snow from Mt. Parnassus to preserve
the delicacy of their oysters frequently is forgotten when fresh fishery
products are transported long distances or held for considerable lengths
of time without benefit of the crushed or “snow” ice now so readily
available at many fishing ports. A publication only a month ago from
the fisheries technological station with which the writer is connected
described some experiments dealing with the transportation of freshly
caught salmon in a tank of chilled sea water aboard the fishing vessel;
already numerous inquiries have been received from Canada and several
other countries for further details, yet it is merely an application of the
cited invention of Archimedes in providing a tank of sea water on
board a Roman vessel, and also almost a repetition of experiments car-
ried out by another station of this Fisheries Research Board of Canada
and published as a public Bulletin in 1931.
Other instances could be cited to illustrate the lack of application
of known beneficial principles, freely published and readily available,
but often forgotten, that could be used to good advantage in the hand-
ling and processing of fishery products from the West Coast of Canada,
the rest of Canada, and elsewhere. But until more attention is paid to
the condition and perishable nature of many such products, careless
handling, gluts of raw materials, or undue haste in processing to fill
a rush order will continue to give rise to instances of dissatisfied cus-
tomers who will think twice before again buying a similar product.
As for the odours from the household cooking of fish, even high
quality fish products certainly can give rise to characteristic odours, but
a a
UTILIZATION OF MARINE PRODUCTS OF CANADA 207
these should be considered just as normal as those from the cooking of
meats, fowl, or certain vegetables. It is unfortunate that fish of slightly
inferior quality causes cooking odours disproportionately more objection-
able than those from a correspondingly inferior quality of most other
food products. Means are known for mitigating the cooking odours
from fish; among the simplest is dipping the fish or fish flesh in a dilute
solution of lemon juice, or its counterpart of harmless citric or tartaric
acid, just before cooking. Such flavour as may be imparted by the juice
or the acids is practically indistinguishable from that imparted in the
common procedure of squeezing a slice of lemon over the cooked fish.
In conclusion, it should be stated that despite what has been im-
plied above concerning sometime deficiencies of quality and home con-
sumption of Canadian fisheries food products, the West Coast of Cana-
da’s fisheries industries are well to the fore in the disposal of their waste
materials not intended for human food. Good use of these materials
is made in the manufacture of by-products. Descriptions of the process-
ing, nature, and potentialities of these by-products have been given from
time to time in publications from technological laboratories of the
Fisheries Research Board of Canada and elsewhere, and current re--
search is promptly reported. Among recent commercially developed
by-products now receiving considerable attention are fish and whale
solubles resulting from the press liquor recovered from the manufacture
of oil and meal, and liquid or semi-liquid digests made by acid, alkali.
or enzymic action on whole fish or fish processing scrap. Both the above
products are finding application in animal feeding and agricultural.
fertilizer fields.
FABRICATION, DEFINITION ET REGLEMENTATION DE LA
SAUCE DE POISSON VIETNAMIENNE “NUOC-MAM”
Par J. GUILLERM et A. VIALARD-GOUDOU
Laboratoire du Nuoc-mam a& UInstitut Pasteur de Saigon, Vietnam
Les diverses populations d’Extréme-Orient, de I’Inde au Japon trou-
vent dans le riz la base de leur nourriture habituelle. Leur ration ali-
mentaire peu sapide est complétée par des sauces azotces et salées qui
en relévent le gotit et enrichissent les préparations culinaires.
Certaines régions utilisent l’azote emprunté au regne végetal, lé-
gumineuse comme le soja (Japon, Chine), d’autres l’azote d'origine
animale des poissons ou crustacées (Cambodge, Indonésie, Laos, Philip-
pines, Siam, Vietnam).
Le nuoc-mam du Vietnam qui nous intéresse ici, comme le patis des
Philippines (Avery, 1950), représente une préparation liquide qui se
différencie par son nom méme qui veut dire “eau de mam’? des pre-
parations pateuses dites “mam” qui sont a peu prés similaires au prahoc
cambodgien, au padec laotien, au bagoong philippin, au trasi malais.
Le nuoc-mam, véritable denrée alimentaire nationale est préparé
en de nombreux centres saumuriers le long des cdtes du Vietnam depuis
Vile de Phu-Quoéc au Sud jusqu’a Cat-Hai au Nord.
Les grands centres de production sont ceux de I’ile de Phu-Quéc
et surtout de la province du Binh-Thuan avec son cheflieu de Phan-
Thiet.
En 1944, derniere année de statistique normale la production était
de 75 millions de litres.
I] y aurait d’y ajouter le nuoc-mam fabriqué avec du poisson d’eau
douce le long des rivieres du Sud-Vietnam et dont la production aug-
mente de jour en jour.
En 1914, sur la demande de I|’administration, Rosé de |’Institut Pas-
teur de Saigon commenca l'étude scientifique du nuoc-mam.
Le 21 décembre 1916, les autorités administratives adoptant les con-
clusions de Rosé prenait le premier arrété qui donnait une définition
légale du nouc-mam et permettait de lutter contre la fraude.
Depuis l'industrie du nuoc-mam a fait l’objet de plus de 25 publica-
tions de toute une série de travailleurs de l'Institut Pasteur de Saigon.
1 Cette expression peut se traduire plus librement par jus de poisson fermentc¢.
208
SAUCE DE POISSON VIETNAMIENNE ‘“‘NUOC-MAM” 209
FABRICATION Du Nuoc-Mam
La fabrication du nuoc-mam minutieusement décrite par Rosé
(1918 a et b) exige des cuves, du poisson et du sel marin. En voici un
résumé d’aprés cet auteur.
Poissons.—Une grande variété de poissons sert a la préparation du
nuoc-mam, les plus petits sont les plus employés car leur lyse est plus
rapide.
Les principales especes péchées et identifiées par l'Institut Océano-
graphique du Vietnam sont suivant Chabanaud (1924) et Chevey
(1931).
Ca nuc Decapterus russelli-Carangidés.
Ca moi Dorosoma nasus et D. chacurda-Dorosomatinés-Clupeidés.
Ca lam Spratelloides delicatulus-Dussumierinés-Clupeidés.
Ca lep Divers Septipinna et Engraulis-Engraulinés-Clupeidés.
Ca com Divers Stolephorus Engraulinés-Clupeidés.
Ca tap poissons de différentes espéces.
En dehors du Ca moi qui fournit une quantité appréciable d’huile,
le Ca nuc et le Ca com sont les poissons de choix du saumurier.
Sel.La qualité du sel est importante. Le sel le plus propre a la
fabrication est le sel marin sec sans aucune matiére étrangére. Le sel
fin n’est pas a recommander. Le produit fourni par le monopole des
Douanes et Régies renferme environ 25 p. 100 d’humidité et de sels
étrangers ol. dominent les sels de magnésium.
Technique saumuriére.—La fabrication du nuoc-mam se fait sui-
vant les mémes principes dans tout le Vietnam. Seuls varient quelques
tours de main propres a chaque saumurier et qui déterminent le fumet,
lee cru:
Cette fabrication peut se diviser en:
a) Mise en cuve du poisson et du sel.
Les cuves sont en général des récipients en bois (parfois en terre
cuite) de forme cylindrique au tronc conique dont le volume varie
entre 200 et 4000 litres. Elles sont munies a la base d’un robinet dont
lentrée est protégée par un filtre. On y place le poisson frais non €vis-
céré et le sel en couches alternées a raison de deux, trois ou quatre
paniers de poisson pour un de sel.
b) Courte macération de trois jours environ qui fournit un premier
jus rougeatre appelé nuoc-bdi.?
Le nuoc-b6i est soutiré, placé dans des jarres ouvertes a l’air pendant
un nombre de jours variable, puis replacé en entier ou par moitié sur
la cuve. L’autre moitié, parfois réservée sert pour les lessivages. Apreés
2 Boi: rejeter. Nuoc-boi: eau rejetée: jus non utilisable.
210 EIGHTH PACIFIC SCIENCE CONGRESS
extraction du nuoc-bdi, la partie supérieure de la cuve est recouverte
d’une couche épaisse de feuilles de latanier qu’on maintient solidement
pressée a l’aide de traverses en bois fixées par des coins.
c) Soutirage du nuoc-nhut (premier jus).
La cuve ainsi mise en pression est laissée au repos pendant deux
A six mois, robinet fermé suivant le poisson, le taux de sel, un premier
soutirage donne un liquide de qualité supérieure riche en azote, de
caracteres organoleptiques tres appréciés. C’est le nuoc-nhut que l’on
vend en partie mais dont la plus grande part est le plus souvent utilisé
pour couper les eaux de lessivage ou pour rendre marchand les produits
trop pauvres en azote des derniers épuisements.
d) Soutirage du nuoc-mam.
Le contenu de la cuve alors épuisé par lixiviation donne le nuoc-
mam. Cette opération s’effectue a l’aide de liquides de macération
provenant de cuves plus anciennes, puis a l’eau salée a 25 p. 100 environ,
elle est renouvelée plusieurs fois et fournit des produits de moins en
moins riches en azote solubilisé. Lorsque l'épuisement est terminé, cette
opération dure parfois plusieurs mois, le liquide de soutirage peu coloré
est trop pauvre et on le laisse dans la cuve pour servir ultérieurement
aux lessivages de nouvelles cuves.
Le résidu resté dans la cuve, constitué par le poisson épuisé est
dénommé Xac mam. Ii est utilisé tel quel comme engrais. Toutes ces
opérations ont leur raison d’étre, que les recherches de laboratoire de
Guillerm (1930) ont permis de mettre en évidence.
La teneur moyenne en azote des diverses espéces de poissons servant
a la fabrication du nuoc-mam varie entre 2,28 a 3,58 p. 100 du poisson
frais.
Le rendement en nuoc-mam d’une cuve est conditionné par la qua-
lité et la quantité du poisson qu’on y met, il est couramment de 70 p-
100. Le fabricant ne pourra extraire de sa cuve plus d’azote qu'il en a
mis.
Le nombre de paniers de poissons peut servir de base au rendement
et C'est ce qui se passe en réalite.
Essai d’industrialisation.
A part quelques sociétés vietnamiennes et chinoises, la fabrication
du nuoc-mam constitue au Vietnam une industrie surtout familiale.
Diverses tentatives de développement de la production par I’installa-
tion d’usines disposant de moyens matériels modernes ont échoué, car
la technique de fabrication généralement suivie consistait 4 exploiter
divers brevets utilisant l’autoprotéolyse du poisson en milieu aseptique
ou antiseptique.
SAUCE DE POISSON VIETNAMIENNE ‘“‘NUOC-MAM” Vaal
C’est une erreur fondamentale car |’autolyse seule de la chair de
poisson n’aboutit pas au nuoc-mam. Les caractéres organoleptiques qui
font apprécier ce produit par les consommateurs odeur, saveur, sont
exclusivement dus a une fermentation microbienne, anaérobie stricte
comme l’ont montré Boez et Guillerm (1930).
DEFINITION ET CARACTERES DU Nuoc-Mam
Le nuoc-mam est donc le produit résultant de la lyse de poissons
avec fermentations limitées par la présence de sel marin.
Au point de vue scientifique c’est le résultat de la protéolyse du
poisson frais dans une solution concentrée de sel marin protéolyse réa-
lisée par les diastases des organes digestifs et par une série de germes
ana€érobies. En méme temps que la molécule protidique se transforme
en acides aminés, il prend naissance toute une scrie de corps provenant
de la dégradation qui donnent au nucc-mam son ardme spécial et ses pro-
priétés apéritives et digestives tant prisées des Vietnamiens. (Vialard-
Goudou 1953).
Le nuoc-mam résultant d’actions biologiques complexes est un pro-
duit a caractéres variables tout comme le vin.
Les stades de la fabrication montrent en effet l’intervention de
divers facteurs.
Ainsi s'il n’y a pas assez de sels, l’action des bactéries deviendra
putréfiante avec augmentation de l’ammoniaque formée, s'il y en a trop,
la protéolyse sera retardée. Un lessivage trop abondant donnera des
produits pauvres en azote utilisable et de faible valeur alimentaire. Un
soutirage trop rapide donnera un nuoc-mam qui se conservera mal par
insuffisance de désintégration des protides.
Cependant un bon nuoc-mam représente certains caractéres qui ne
varient que dans des limites bien déterminées.
Quelle que soit la durée de la fabrication il n’est pas posible de
dépasser la proportion de 75 a 77 d’azote dosable par la méthode au
formol de Sérensen pour 100 d’azote total. Si la teneur en azote formol
est inférieure a 50 p. 100 le nuoc-mam obtenu est instable; la moitié
au plus de l’azote formol peut étre sous forme ammoniacale: un taux
plus élevé d’azote ammoniacal indique une désamination des acides
aminés avec altération du produit.
La différence entre l’azote total et l’azote ammoniacal donne I’azote
organique; la différence entre l’azote formol et l’azote ammoniacal
donne l’azote des acides aminés. En outre un certain taux de sel, 25 p.
100 en moyenne, est nécessaire pour assurer la conservation du nuoc-
mam.
212 EIGHTH PACIFIC SCIENCE CONGRESS
REGLEMENTATION DU Nuoc-MAM
Nous citerons simplement le dernier arrété du 17 novembre 1943
qui reprend l’essentiel de l’arrété du 21 décembre 1916. Voici les cing
premiers articles qui nous intéressent directement:
Article premier.—En Indochine, il est interdit de fabriquer, d’ex-
poser, de mettre en vente et de vendre, sous la dénomination de nuoc-
mam ou de nuoc-nhut ou des termes synonymes, tout produit autre que
celui obtenu par les usages courants et loyaux de la technique saumu-
riere traditionnelle annamite.
La dénomination de nuoc-nhut est réservée aux premiers jus des
cuves, dont la fraction liquide est exclusivement constituée par l’eau de
constitution du poisson.
La dénomination de nuoc-mam deésigne les produits obtenus par
la dilution du nuoc-nhut ou par |’épuisement des cuves a l'eau salée.
Ces produits doivent répondre aux conditions exigées par les articles
suivants.
Art. 2._Les nuoc-nhut et nuocmam constitués par la dissolution
de la chair de poisson a un certain degré de désintégration sont des
solutions limpides sans dép6t appréciable, d’odeur et de saveur sui-gén-
éris, suffisamment salées pour ne présenter aucun indice de putréfaction.
Art. 3.—Les qualités substantielles du nuoc-nhut et du nuoc-mam
dépendent:
1°) de leur richesse en poisson;
2°) du degré de désintégration de la chair du poisson;
3°) de leur valeur alimentaire.
La richesse du poisson est donnée par la teneur en azote total
exprimée en gramme par litre.
Le degré de désintégration de la chair du poisson s’exprime par
la teneur en azote formol qui doit étre comprise entre 50 et 77 p. 100
de l’azote total.
La valeur alimentaire ou teneur en principes utiles exige que le
taux d’azote ammoniacal ne dépasse pas la moitié de |’azote formol.
Le nuoc-nhut et le nuoc-mam fabriqués et mis en vente devront
répondre aux caractéristiques suivantes:
Pour le nuoc-nhut:
INES MORN Sola hob bob0 5 olawod ase 18 g. par litre au moins.
LNAHTS: WOT GS Sob boo sou Soe de T 50 a 77 p. 100 de J’azote total.
AZOLE vaImmoniaCaley | vers. el: 50 p. 100 au plus de Il’azote formol.
Pour le nuoc-mam:
AZOLE MLO Callig Paar naturel sve epee nnn cron is 15 g. par litre au moins.
ENZO LE PLOTINO Mate torso tn tein rerelary. 50 a 77 p. 100 de l’azote formol.
Azote ammoniacal vere ee 50 p. 100 au plus de l’azote formol.
SAUCE DE POISSON VIETNAMIENNE “NUOC-MAM” 213
Tout nuoc-nhut ou nuocmam dont le taux d’azote ammoniacal
atteint ou dépasse 75 p. 100 de l’azote formol est considéré comme cor-
rompu.
Art. 4.—Est autorisé: l’addition du sucre caramélisé ou non, mélas-
se, miel, thinh ou riz grillé dans les cuves de préparation.
Art. 5.—Sont interdits et considérés comme manoeuvres illicites:
a) la mise en cuve de poisson en mauvais état de conservation;
b) V’enrichissement des eaux de lessivage ou des nuoc-nhut et nuoc-
mam par toute matiere azotée autre que celle provement des cuves;
c) lusage d’eaux de lessivage ammoniacales ou putrides;
d) Vusage des antiseptiques, des produits chimiques, des matieres
colorantes.
Cet arrété supprime le privilege des nuoc-mam du Nord-Vietnam
qui pouvaient contenir seulement trois grammes d’azote total par litre
et établit ainsi une législation unique pour 1|’Indochine.
Peu apres, l’arrété du 29 mars 1944 fixa une période de transition
de deux ans pour la teneur en azote total, soit:
1] g. pour le Cambodge, la Cochinchine et les provinces du Binh-
Thuan, Khanh-Hoa, Haut-Donnai et Lang-Biang.
3 g. pour les autres centres de production.
Par décision du Gouvernement du Vietnam cette période de transi-
tion dure encore. |
RESUME
Pour permettre l’absorption d’une alimentation a base de riz, tous
les peuples de ]’Extréme-Orient l’additionne de sauces condiments salées
a base de matiéres protidiques fermentées (soja ou poisson).
Au Vietnam, c’est la sauce de poisson “nuoc-mam’’ trés voisine du
“patis’” des Philippines et dont la production annuelle en 1944 fut de
75 millions de litres qui remplit ce réle.
Apres un bref exposé de la technique de fabrication les auteurs
rappellent que ce sont les travaux des chercheurs de I’Institut Pasteur
de Saigon exposés dans plus de 25 publications depuis 1918 qui ont
permis de fournir la définition et de fixer les caractéres d’un bon nuoc-
mam. Ils terminent en donnant la derniére reglementation qui peut
intéresser les pays, comme les Philippines, ot l’on consomme des pro-
duits analogues au nuoc-mam.
BIBLIOGRAPHIE
Avery, A. C. (1950)—Fish processing handbook for the Philippines. Fish
and Wildlife Service, U.S. Dept. of the Interior, Research Report No. 26,
pp. 24-27.
Borez, L. et GuILLeRM, J. (1930)—Le facteur microbien dans la fabrication
de la saumure indochinoise (nuoc-mam). C, R. Ac. Sci. 19¢, 534,
214 EIGHTH PACIFIC SCIENCE CONGRESS
CHABANAUD, P. (1924)—Inventaire de la faune ichtyologique de l’Indochine
—lére liste. Bull. Econom. Indoch., fascicule VI, No. 169, 561.
CHEvEY, P. (1931)—Inventaire de la faune ichtyologique de l’Indochine—
2eme liste. Publication Inst. Océanogr.. Indochine—19é note.
GUILLERM, J. (1930)—L’explication scientifique d’un phénoméne empirique:
la production du nuoc-mam. Transactions of the 8th. Congress of the
F.E.A.T.M. Bangkok, 1, 122.
Ross, E. (1918a)—Recherche sur la fabrication et la composition chimique du
nuoc-mam. Bull. Econom. Indochine 1918, 129, 155.
Rosg, E. (1918b)—Le nuoc-mam du Nord, composition chimique et fabrication.
Bull. Econom. Indochine 1918, 132, 955.
VIALARD-GoubOoU, A. (1953)—Etude chimique, bactériologique et valeur ali-
mentaire de la sauce de poisson vietnamienne nuoc-mam. Proceedings of
the Eighth Pacific Science Congress (sous presse).
STUDIES ON AGAR-AGAR IN JAPAN *
By T. YANaGAWA? and K. Tani?
INTRODUCTION
Agar-agar, a kind of carbohydrate contained in red algae belonging
to Gelidium species, is one of the celebrated local products of Japan,
manufactured by a special process which was developed in this country
nearly 300 years ago. Numerous investigations have been made from
the point of view of both applied and pure science.
We believe it advisable to commence with a brief description of
the customary method of manufacturing agar-agar in Japan(l). The
cleaned algae is first extracted with boiling water faintly acidified with
sulphuric acid, and by natural cooling of the extracted filtrate, agar-
agar hydrosol can be coagulated as a gel (1-2%). After it is cut pro-
perly it is placed outdoors in winter, so that the night cold freezes it,
while during the day the warmth gradually thaws the frozen ice into
water, which flows away. The last step is to dry it in the open air until
the product is obtained in a final dry form. Chemical changes in the
course of preparation have been investigated by Araki (2).
The above-mentioned process takes more than half a month and
since it depends to a great extent on natural weather conditions, it
must be considered unsatisfactory. In order to remove this drawback,
several new methods have recently been devised, such as mechanical
freezing or the application of heat from hot springs. ‘The main problems
to be solved are how to produce economically and efficiently a good
quality product by mechanical means and how to produce agar-agar
from Gracilaria confervoides by chemical treatment.
I. PROPAGATION OF SEAWEEDS USED FOR AGAR-AGAR
Efforts have been made to promote the propagation of the seaweeds
which are used as the raw material of agar-agar. For instance, the reefs
were cleaned with simple implements so as to improve the production
capacity of the growing areas and the growing areas were extended by
submerging rocks and stones on the sea-bottom. Except in a few cases,
* By courtesy of the Japanese Government, a Member Government of IPFC.
1Doshisha University, Kyoto, Japan. : : :
2 Northeast Sea Regional Fisheries Research Institute, Shiogama City, Japan.
215
216 EIGHTH PACIFIC SCIENCE CONGRESS
however, these methods have not always been effective and further work
must be carried out.
The seasons for spore formation and liberation have been studied
by many authors. In Gelidiwm Amansii the tetra-spores begin to be
shed late in spring when the temperature of the sea water rises to 21°-
22°C., and the carpospores at temperatures of 24°-25°C. (3) (5). In
Gelidium fastigiatum both spores begin to be shed at about 20°C. (4).
The liberation of the matured spores occurs almost every afternoon
during the season. Sometimes about 100 spores per liter were founded
in the sea water near a Gelidium field. ‘The spores fix themselves on
the rock surface after having lain in contact with it for about ten
minutes (5).
The germination of spores and their later development into young
plants have been reported on by Ueda and Katada (6) (11). According
to their reports, some of them rise up erectly to form an upright bush,
while others form creeping stolons which afterwards emit new upright
buds.
The temperature ranges for normal germination were experiment-
ally estimated at 10°-30°C. (optimum 25°—26°C.) in Gelidium Aman-
sit. (7) and at 10°-25°C. (optimum 16°C.) in Gelidium subfastigia-
tum (4). Low salinity (<1.020) delays the growth of primary rhizoids.
Colors of the prevailing light seem to have some effect on the growth
of the germ lings of Gelidium.
In the northern part of Japan negative correlation was found be-
tween the yields of Gelidium and the sea water temperature in winter,
and Gelidium was not found in the sea where the minimum temperature
fell below 2°C. (4).
Okamura (8),, Ueda (9), and Ueda-Katada(6) obtained some data
for the growth of Gelidium Amansii in the southern part of Japan.
The plants are perennial. They grow very slowly in autumn, but ra-
pidly in winter and spring, reaching lengths of about 10 cm. in the first
year, about 18 cm. in the following year and more than 20 cm. in the
third year. ‘The annual yield amounts at a maximum to about 3 Kg.
wet weight per square meter.
Okamura (8) found that small pieces of Gelidium plants regenerate
rhizoids and continue to grow on a new substratum.
The researches on the relationship between Gelidiwm and other
algae and animals living in association on the Gelidiwm field may be
important, but the work on this subject is still incomplete. The young
plants are damaged by being covered by algae such as various species
STUDIES ON AGAR-AGAR IN JAPAN PANT (
of Corallinaceae (10) and Helposiphonia(11). Some Gastropoda were
found to feed on them(11). Research is now being carried out in co-
operation with phycologists on the ecological relationship between Geli-
dium and Corallinaceae.
Some trials to “cultivate” these algae have been made. Kinoshita
and Hirobe (12) were successful in seeding the spores of Gracilaria
confervoides on an experimental scale. Fujimori hung the Gelidium
plants on hemp-palm rope from a bamboo buoy in a calm inlet. He
found that the plant grew twice as much in weight every month of the
late winter as it had in the preceding month (S. Suto).
IJ. THE RELATION BETWEEN JELLY-STRENGYH AND CHEMICAL
CONSTITUENTS OF AGAR-SUBSTANCES
Generally speaking, mucilages of red algae (geloses) are ester-sul-
phates of galactan, but there are in fact various kinds. After studying
each gelose for each kind of red algae, the following results have been
obtained: The more sulphuric acid is combined in it the weaker is
the jelly-strength obtained, and vice versa. Sulphuric acid content va-
ries widely from | to 259% (13). There are two kinds of sulphuric acid
combined, one of which remains in the ash when the geloses are burnt
while the other does not. Sulphuric acids are combined in geloses by
two types, one of which is R-SO,-R’ and the other R-SO,-M (R being
polysaccharide and M metal). Analysing geloses of many kinds of red-
algae, and representing the results on a graph having a mel-ratio of
hexose/total SO, as its ordinate and that of total SO,/SO, in ash as its
abscissa, we get a line nearly parallel to the ordinate for geloses of all
red-algae which have sufficiently strong jelly-strength to be utilized as
material for agar-agar, and similarly we get a line parallel to the abs-
cissa for geloses of red algae having little jelly-strength and which are
utilized for stiffening textiles. At the same time, geloses of these kinds
of red algae which have a weaker jelly-strength are found to be repre-
sented by a line located intermediately between the two above-men-
tioned lines (13). Moreover, when gelose (SO, ca. 9%) of a kind of
Gracilaria confervoides, represented by the intermediate line, is treated
with dilute alkali solution, a part of the sulphuric acid is easily sepa-
rated, resulting in an increase of jelly-strength. “Those which have 9%
sulphuric acid are very weak in jelly-strength, but when the sulphuric
acid content is finally reduced to 2% (comparable with that of agar-
agar), jelly-strength increases remarkably so as to be comparable with
that of agar-agar (14). It is also reported (15) that the addition of
218 EIGHTH PACIFIC SCIENCE CONGRESS
CaCl, during alkali-treatment favors jelly-strength. Taking advantage
of this, attempts have recently been made to manufacture agar- aga from
cheaper material, e.g., Gracilaria confervoides.
III. RHEOLOGICAL STUDIES OF AGAR-HYDROSOL AND GEL
a) Visco-elasticity of agar-hydrogel(16):—The experimental pro-
cedure adopted was that used by Schwedoff (1889), Hatschek and Jane
(1926), and Poole (1926), the apparatus being composed of two concen-
tric cylinders, the intervening gap being filled with gel and the inner
cylinder being suspended by a tortion wire. When the top of the tor-
tion wire is twisted, the rigidity G of the gel is determined; the elastic
equilibrium is attained immediately, and the viscous flow commences,
so that the inner cylinder is observed to move gradually.
Experimental results obtained are as follows. Elastic deformation
is Hookeian in the range of strain studied (shear rate 0.1—0.6), and ri-
gidity G markedly increases with the increase of concentration:
G(dyne/em.2) 2.1X10-1 4.8x10-1 1.27 1.46X10 3.7102
Cone. (%) 0.039 0.053 0.062 0.12 0.28
Viscous flow is anomalous; it increases along with the increase of
shear strain, namely with the increase of deflection of the inner cylinder.
The visco-elastic behaviour of agar-gel is described by the three-element
mechanical model.
b) Thermo-elastic property of agar-hydrosol (17):—Aqueous solu-
tion of agar, gelatin, pectin, etc. or benzene solution of some metallic
soaps make elastic jellies. The principal characteristic of these gel states
is shape-durability and high elasticity in spite of a relatively high con-
tent of solvent.
The thermo-elastic property of agar-hydrogel was studied according
to Meyer and Ferri’s scheme (1935) for determining the elasticity of
rubber. ‘Thus, both the energy contribution and the entropy contri-
bution to elasticity can be discussed from the stress-temperature curve
under a constant strain.
The experimental device was the same as has been mentioned in the
previous section (a). Experimental results show that the elastic force
gradually decreases with increase of temperature. This means that the
elastic force of gel is concerned with the increase of internal energy and
also with that of entropy by deformation; this situation is similar to
the behaviour of metals and crystals.
The nature of the high elasticity of gel seems to be somewhat dif-
ferent from that of rubber elasticity, which is chiefly attributed to the
STUDIES ON AGAR-AGAR IN JAPAN 219
decrease of entropy by deformation. The agar molecule is considered
to be a galactan chain accompanied by sulphate radicals here and there.
A lattice-like configuration of these poly-electrolyte chains in water
might be the internal structure of the gel state.
c) Viscosity of much diluted agar-hydrosol (18) :—The gel-forming
property of agar is so strong that even a 0.04% solution distinctly ex-
hibits elasticity as has been described in (a), and anomalous viscosity
is observed in these concentrations. Accordingly it is necessary to ex-
periment with much diluted (under 0.04%) systems in order to test the
purely viscous behaviour of the solution.
Measurements were made by the ordinary methods using Ostwald’s
visco-meter in the concentration range 0.01—0.04%, and ésp./c (specific
viscosity divided by concentration) were plotted against concentration.
ésp./c decreases with the decrease of concentration, passes through
the minimum, and then increases again with further decreases of con-
centration, and if a strong electrolyte such as KC] is added to the solu-
tion, ésp./c decreases eventually with the decrease of concentration.
This behaviour is the same as that of other poly-electrolyte solutions.
Intrinsic viscosity defined as [é] = [ésp./c]c — 0 is concerned with
the extension of the molecule in the solution. And from the evaluation
of the intrinsic viscosity of agar-hydrosol, it is supposed that this poly-
electrolyte has a much stretched non-spherical configuration in water;
[€] of agar-hydrosol is much larger than that of the ordinary random-
coil non-polar polymers.
ITV. ORGANIC-CHEMICAL INVESTIGATIONS ON AGAR-AGAR
Araki has investigated the chemical constitution of agar-agar. He
isolated D, L-galactose and L-galactose (19) and reported on acetylated
agar, heterogeneous composition, and percentage compositions (20) of
agar-agar. lL-galactose from methylated agar has been confirmed (21).
2,4,6-trymethyl-D-galactose, 2,4-dimethyl-3, 6-anhydromethy]-L-galacto-
side, 2-methyl-3, 6-anhydro-L-galactose dimethylacetal and pentamethy]-
D-galactosido-3, 6-anhydro-methyl-L-galactoside have been isolated from
methylated agar (22). 3,6-anhydro-galactose has been synthesized (23)
and 3,6-anhydro-L-galactose has also been isolated from agar-agar (24)
as its dimethylacetal by methanolysis of agar-agar and as its diethylmer-
captal by mercaptolysis, from which 3,6-anhydro-L-galactose has been
separated in free state. Again isolation and chemical constitution of
agarobiose and isoagarobiose have been studied (25). A new disaccha-
ride C,.H,,O,, has been obtained by hydrolysing agar-agar with IN
220 EIGHTH PACIFIC SCIENCE CONGRESS
H,SO, for an hour and has been named Agarobiose by one of the au-
thors. ‘The same substance was subsequently obtained from agar-agar
as its dimethylacetal by partial methanolysis and as its diethylmercaptal
by partial mercaptolysis, from which free agarobiose has been isolated
respectively by the separation of methyl alcohol and ethylmercaptan.
It reduces Fehling’s solution and gives q-methyl-D-galactoside and
3,6-anhydro-L-galactose dimethylacetal by methanolysis with 2% HCI-
CH,OH. By preliminary treatment with 0.5% HC1-CH,OH and fur-
ther methylation with Purdie’s reagents, agarobiose gives hexamethyl-
agarobiose dimethylacetal (b.p. 155-6° /0.052 mm., [a], — 11° [H,O]).
When this methylated derivative is left in IN H,SO, at ordinary
temperature for 182 hours, it is changed to hexamethyl agarobiose,
C,,H,,0, (OCH;),, .[a], — 44° (H,O).
As hexamethyl-agarobiose dimethylacetal gives 2,3,4,6-tetramethy]l-
methyl-D-galactoside and 2,5-dimethyl-3,6-anhydro-L-galactose dimethyl-
acetal by methanolysis with 2% HCI-CH,OH, it can be concluded that
the hexamethyl-agarobiose dimethylacetal is 4-2,3,4,6-tetra-methyl-D-ga-
lactoside< 1,5>-2,5-dimethy1-3,6-anhydro-L-galactose dimethylacetal. Fur-
ther, from the fact that the specific rotatory power of the acetal is small,
it can be assumed that the sugar is a #-galactoside. ‘Therefore, the
chemical constitution of agarobiose is illustrated by Figure A:
CHO + as i
HO-C-H H-C-OH
BO |
H-C—— HO-C-H O
Eoin HO-C-H
ee a9 |
HO_ 62H "|
H | — CH.OH
Fic. A.—Agarobiose
The constitution of agar-agar together with the mechanism of the
formation of 3,6-anhydro-L-galactose in marine algae was discussed (26).
Taking into consideration the isolation of 2,4,6-trimethyl-D-galactose
and 2-methyl-3,6-anhydro-L-galactose from the methylated agar by hydro-
lysis as well as the isolation of agarobiose from agar-agar by partial hy-
STUDIES ON AGAR-AGAR IN JAPAN 221
drolysis, it may be possible to conclude the existence of the above linkage
(Fig. B), in the molecule of agar-agar (26):
/
O
i
CH CH
HO-C-H H-C-OH
) | Bo |
Hee O ——C-H O
| |
H-Gsl] 00 / HO-C-H
ee |
io H-C
H.C CH.OH
Fic. B
Further it must be mentioned that the partial methanolysis product
of agar gives about 50° of agarobiose dimethylacetal.
The above-mentioned experimental results cannot be explained by
the formula proposed by Jones and Peat (1941), showing that nine re-
sidues of D-galacto-pyranose are combined mutually by 1,3-glycosidic
linkage and at reducing end of D-galactose residue joins L-galactose-6-
sulphate or 3,6-anhydro-L-galactose through 1,4-linkage, but rather it
may be explained better by the assumption that in the molecule of agar,
agarobiose units are repeated.
Comparative studies on the chemical constituents of agarous sub-
stance of Gelidium Amansii, Campylaephora Hypnaeoides, Acanthopel-
tis Japonica, and Gelidium subcostatum have been reported.
REFERENCES
1) YANAGAWA, T. Kanten (Agar-agar), Book (Japanese), 352 pages (1942).
2) ARAKI, C. J. Chem. Soc. Japan; 58, 1085 (1937).
3) TAKAYAMA, K. J. Fish. Scv.; 34, 211 (1989).
4) KINOSHITA, T. (1950).
5) Suto, S. Bull. Jap. Soc. Sci. Fish.; 15, 671 (1950).
6) Uspa, S. and M. Katana. Ibid.; 11, 175 (1948).
7) KatTapA, M. IJbid.; 15, 359 (1949).
8) Okamura, K. J. Imp. Fish. Inst.; 18, (3), (1921).
9) Uspa, S. Bull. Jap. Soc. Sci. Fish.; 5, 183 (1986).
10) TAKAMATSU, M. Trans. Res. Inst. Nat. Resources; 6, 55 (1944).
11) Uspa, S. and M. Katana. Bull. Jap. Soc. Sci. Fish.; 15, 354 (1949).
222 EIGHTH PACIFIC SCIENCE CONGRESS
12) Kinosuita, T. and T. Hirose. Monthly Rep. Hokkaido Fish. Inst.; 3,
(%), 27 (1946).
18) YanaGAwa, T. Bull. Jap. Soc. Sci. Fish.; 17, 305 (1952). Doshisha Eng.
Review; 1, 53 (1951).
14) YANAGAWA, T. Bull. Osaka Ind. Res. Inst.; 17, (6), (19386): Bull. Jap.
Soc. Sci. Fish.; 6, 274 (1938): Ibid.; 10, 237 (1942).
15) FuNaAKI, K. and Others. Ibid.; 16, 401, 419 (1951) : Ibzd.; 18, 245 (1952).
16) NakaGcawa, T. J. Chem. Soc., Japan; 72, 390 (1951).
17) NaxaGcawa, T. Ibid.; 72, 518 (1951).
18) Nakacawa, T. Ibid.; 72, 625 (1951).
19) ARAxr, C. Ibid.; 58, 958 (1987): 59, 424 (1988).
20) Araxi, C. Ibid.; 58, 1838 (1937): 58, 1351 (1937).
21) Araki, C., Y. HASHI and K. ARAI. Ibid.; 62, 845 (1941).
22) Araki, C. Ibid.; 58, 1862 (1937): 59, 304 (1938): 61, 775 (1940): 62,
733 (1941).
23) ARAKI, C. and K. Arar. I[bid.; 61, 503 (1940).
24) ARAKI, C. I[bid.; 65, 725 (1944).
25) Araki, C. Ibid.; 65, 533, 627 (1944): Unpublished.
26) ARAKI, C. Memo. Kyoto Tech. Univ.; 2, B, 17 (1958): Coll. Treatises
Commemoration 45th. Anniv., Kyoto Tech. Coll.; 76 (1948).
27) ARAKI, C. Ibid.; 89 (1948).
iw)
iw)
(Se)
STUDIES ON AGAR-AGAR IN JAPAN
Mol ratio
nO
o)
15
10
: (18)
xK (19
(ai,)(12)(15)" (12) (8) (26)
: 2 4 6 8 Mol ratio
ty
yy,
of s
ss CURA
ii
Oa
Ae
1
(uy
Oat Dion
B AC
th
4
A REPORT ON THE STUDIES MADE IN JAPAN ON
PEARL CULTURE
By YosuiicH1 MaTsul
Nippon Institute for Scientific Research on Pearis
Kyoto, Japan
The culture of pearls in Japan dates from 1893 when K. Mikimoto
first produced by culture blister pearls from Pinctada martensii (Diin-
ker). Then in 1904, T. Mise first succeeded in cultivating spherical
pearls. He was followed by T. Nishikawa and K. Mikimoto, but it
was not until 1915 that M. Fujita organized Nishikawa’s method on
an industrial basis and brought the products to the market. In 1938,
the total production at 289 culture grounds reached a peak of 560 ke.
per annum. After this the production slumped and the number of
culture grounds was also reduced to 106, which were even closed en-
tirely at one time. However, the recovery starting from 1948 was
spectacular, and in 1952, the number of culture grounds exceeded 1200
with a total output of 400 kg. a year. The fresh-water culture of pearls
has also been continued since it was successfully experimented on Hy-
riopsis schlegelt (Martens) in 1924, and now has an output of about
4 kg. a year.
Until recently the method of pearl culture had been veiled under
the protection of a patent. But the increasing demand after 1946 made
it imperative to reorganize the industry on a scientific basis. Thus the
Nippon Culture: Pearl Co., Ltd., which is the organization of Japanese
pearl culturists, established a laboratory to carry on basic studies on
pearl and its culture, in close cooperation with Kyoto University.
The laboratory afterwards became independent and was reorganized
into its present form. At present there is a project conceived by the
Government for setting up the National Research Institute so as to
meet the marked increase of the numbers of both the culturists and the
scientific workers.
The most important task in the study of pearl culture is to find
out the process in which a pearl is formed. ‘The Japanese pear! cul-
turists, having developed a high art, seem to have accomplished this
task. But it is plain, if you observe how pearls are formed under
natural circumstances, that while they found out a method of trans-
planting pearl secretion tissue, they have not yet clarified the whole
225
226 EIGHTH PACIFIC SCIENCE CONGRESS
process of pearl formation. K. Isowa tried an experiment on Pinctada
martensit and obtained a number of seed pearls by giving chemical
or physical stimuli to its aductor muscle and anterior retructor muscle,
and patented his method. Y. Matsui, working with Isowa, supposed
that a substance similar in function to a hormone was first formed by
the stimulus of a wound, and this hormone-like substance in its turn
caused abnormal propagation and functional reverses of the epithelial
cells in the mantle. On this hypothesis, he made various experiments
with fruitful results. As a result of his histological studies of the mantle
tissues of Pinctada martensii and Hyriopsis schlegeli, Y. Ojima identi-
fied four kinds of secretory cells, but after testing the calcium contents
in the tissue, he concluded that these did not make the glands spe-
cialized for secreting calcium. Ojima and T. Watanabe are now en-
gaged in the study of the structure and the process of formation of the
pearl sac. I. Kawakami transplanted the mantle tissue of Pinctada
martensw: in the gonad tissue, and saw the outer epidermis propagate
and complete the formation of pearl sacs in fifteen days, while other
tissues degenerated. He also reported his studies on the regeneration
of the mantle.
With regard to the formation of pearls, the important question
that the scientists must answer is: What is the mechanism of the cal-
cium deposition as well as of the shell formation? Our recent efforts
have been directed to discovering a new explanation to answer this
question.
Y. Matsui, S. Tanaka and Y. Uchida are now carrying on experi-
ments on the calcium deposition in Pinctada martensi and Hyriopsis
schlegeli, using the isotope Ca,;. When the animal was kept in water
containing Ca,,, the Ca,, absorbed in the internal organs, with the
exception of the liver, reached a maximum at the fifteenth hour and no
change was observed at the thirtieth hour. In the mantle, the maxi-
mum was reached at the sixteenth hour and a reduction was observed
at the thirtieth hour. In the shell and the pearl, the presence of Ca,,
was noted at the fourth hour. When Ca,; was injected in the body
of the mollusc, it was diffused in the internal organs in 1—2 hours and
began to be excreted out of the body at the fourth hour. While the
shell is mainly composed of calcium carbonate, it also contains a cer-
tain amount of conchiolin, which is an organic matter. Many points
as to the attributes of the conchiolin are yet unknown. S. Tanaka
and H. Hatano have undertaken a biochemical study of the conchiolin,
which has led them to discover that the conchiolins in both the shell
and the pearl are of the same composition and that proline, oxyproline
and sulphur contained amino acid are found in either of the two,
STUDIES MADE IN JAPAN ON PEARL CULTURE 227
while halogen contained amino acid as gorgonin and spongin, are
absent. Y. Matsui, M. Takanami and T. Hirota measured the amounts
of amino acids in normal and baroque pearls in a microbiological assay
and found that while there was no difference in the amounts of acidic
amino acids between the two pearls, there were significant variances
in the basic amino acids: namely, in the normal pearl layer, glycine
registered 21.9%, against 9.8% and leucine 16.4% against 11.3%; and
in the abnormal layer of baroque pearls, histidine registered 4.7%
against 0.5%, arginine 8.3% against 4.9%, lysine 7.4% against 1.7%,
threonine 1.9% against 0%, etc. D. K. Ikenaga, who modified and em-
ployed Clark’s method, manometrically ascertained that there was a
variation in the activities of carbonic anhydrase in Pinctada martensii,
corresponding to the specific organs and age of the animal and the
seasons of the year. T. Tsuji demonstrated by a histochemical study
that while carbonic anhydrase was almost absent in the epithelium on
the inside and at the top of the mantle, it was found in abundance in
the epithelium contiguous to the shell. He is also carrying on a study
on the distribution of nucleic acid. Y. Ojima and Ikenaga, who have
undertaken a histochemical study of the alkaline phosphatase in the
mantle and the pearl sac of Hyriopsis schlegeli, have discovered that
it is distributed in a remarkable amount in the epithelium at the top
of the mantle and that while it is found neither in the mucus glands
at the side of the mantle adjacent to the shell nor in the epithelial
cells of the pearl sac, a considerable amount of it is present in that
part of the tissue which has been injured by the insertion of a pearl
nucleus.
Physiological and ecological studies of pearl oysters are also being
carried on with great animation, as these can be directly applied to
the culture of pearls. Examples are S. Mori’s study in the respiratory
physiology and daily rhythmic activities of Pinctada martensi, 1. Hon-
jo’s study concerning their reaction to light, N. Kawamoto’s study of
the artificial spawning in ordinary and diluted sea water, H. Koba-
yashi’s and J. Matsui’s experiments with various degrees of the salinity
and temperature of sea water and other environmental conditions, and
the studies taken up by S. Kobayashi and the staff of the Mie Prefec-
tural Fisheries Experimental Station on the generation and larva of
Pinctada martensii. C. Ashikaga, S. Tanaka, H. Hatano and others
have made a number of reports on their studies of the chemical com-
position and its variation according to the seasons of the year.
Researches into the water, the bottom of the Pearl Culture ground
and the plankton are proceeding under the collaboration of Y. ‘Toyo-
hara, J. Yamaji, M. Motojima, M. Morishima, Y. Inoue and others.
228 EIGHTH PACIFIC SCIENCE CONGRESS
Earnest hopes are attached to these researches in view of the degrading
tendency of the qualities of the products due to the recent increase
in the number of pearl culture grounds.
An important aspect of the art of pearl culture is concerned with
the scientific evaluation of the quality of a pearl. For this, it is in-
dispensable to clarify the essential properties of pearls through physical
and chemical approaches. Y. Uchida and M. Ueda made clear the
interrelation between the stratiform makeup of the pearl and its
irridescence. ‘IT. Watanabe is engaged in a research into the interrela-
tion between the color and the thickness of a pearl layer and also
into the crystallization of the substance. Y. Matsui and T. Hirota have
reported that there is a marked difference in the crystalline form be-
tween the normal and the baroque pearls.
Y. Uchida discovered by spectroanalysis that there were remarkable
differences in the mineral contents among pearls with different colors.
T. Kosaki’s report has disclosed that a pearl contains 16-66 ,/100g of
porphyrin and 5-70 ,./100g of metalloporphyrin, varying with the color.
Recently our laboratory has been made the center of the studies
devoted to the discovery of the conditions on which to evaluate the
qualities of pearls scientifically. With the help of Hardy’s self-record-
ing spectrophotometer, T. Fukuda and his collaborators examined
pearls with various colors and lusters, and have proved the possibilities
of classifying them according to their substantial colors. ‘They have
also demonstrated that they can calculate the thickness of the pearl
layer by rating the surface color which is formed by the interference of a
reflexion. Besides these studies, various other approaches are now be-
ing tried to test the pearl as a jewel.
FUNDAMENTAL STUDIES ON THE FISH LAMP
By N. Y. KAwAMoTo
Faculty of Fisheries, Prefectural University of Mie, Tsu
Mie Prefecture, Japan
It is a well-known fact that animals react to light, positively or
negatively. Phototaxis of protozoa such as Paramecium and Euglena
has been studied by many investigators, and reaction of the earthworm
to light is also a well-known fact. Especially for insects, most efficient
lamps were recently discovered by means of studying complex factors
between visibility of retina of their eyes and their behavior.
Fish lamps have been used in every country in the world since
ancient times to increase efficiency of fishing. In Japan, the torch-light
has been used since olden times for collecting the fishes. Nowadays,
electric fish lamps are employed by almost all fishermen in our country.
However, maximum efficiencies could not be expected because of un-
reliable theories about fish lamps. Dr. M. Tauchi (1926) and Dr. T-
Sasaki (1950) studied the effects of fish lamps upon fish shoals in the
sea, but the studies of the two investigators were chiefly on the side of
physics, and biological aspects were not fully considered. Therefore,
the fundamental reason for the method of using fish lamps was not
yet clear.
Since 1947 the writer has studied, with co-investigators, the re-
lation between fish behaviour and fish lamps, using methods of physiol-
ogy and experimental zoology.
For these experiments, many kinds of young marine fishes were
used and their reaction against various kinds of light in the dark
room was determined. Studies were made of the behaviour of adult
horse-mackerel in a rectangular net which was set down off the coast
of the sea in front of the Ichthyological Research Institute, Shimoda,
Izu peninsula, Japan.
EXPERIMENTS
In the laboratory, the writer adopted a lusterless, black, round
wooden tank, which was 100 cm. in diameter and 25 cm. in depth; and
the tank was divided radially into eight compartments, which were
open to each other at the center. The tank was filled with water to
a depth of 20 cm. and a color filter, was placed over a light window of
each compartment and 60-Watt Mazda electric bulbs were set 20 cm.
229 \
230 EIGHTH PACIFIC SCIENCE CONGRESS
above each of them. In order to make the illumination for the colored
lights equal to 50 lux on every water surface of the eight compartments,
some sheets of white paper were piled up over these filters for adjusting
the light. The color filters were arranged in two ways, one in the order
of wave length and the other at random in order that the fish might
not become familiar with the color arrangements.
We observed the rates of frequencies of the time of entrance of
the fishes into each compartment of various lights, and compared the
rates with the relative energies which were calculated by the transpar-
encies of the filters, sensibilities of selen photometer and radiant ener-
gies of the lamp, and judged their phototaxis tendencies. By this meth-
od, we got considerable experimental results and will show the ab-
stract of these as follows:
One of my co-workers, Dr. Osaki, studied the relation between the
phototaxis and the aggregation of young marine fishes, because, in a
biological phenomenon, the aggregation frequently comes into ques-
tion. Some investigators who have studied on the fish aggregation, have
probably made the assumption that apparent gatherings are real ag-
gregations. Nevertheless, it is possible that two fishes actually form an
aggregation even when they are so apart from each other that they may
be considered as a group. ‘Therefore, it is next to impossible to con-
clude from the appearance whether a gathering is an aggregation or not.
In our studies on the phototaxis of fish, it is necessary to conduct re-
search on how aggregation affects the phenomenon and what difference
exists between the phototaxis of the individual fish and that of the ag-
gregated fish. The shape of the curves of fish gathering rate varied in
accordance with the number of fishes employed and wave lengths in the
experiments, but, at any rate, fishes are constantly forming various types
of aggregation, the shapes of gathering rates of each individual were at
random, while those of two or more numbers of fish in an aquarium
coincided with each other and maximum values of these appeared at
the range of green and blue colors in common fishes (Dr. H. Ozaki).
The types of phototaxis of fish were found to be divided into two.
One was the greatest fish-gathering rates in the range of wave lengths
of green and blue as were seen in Oplegnathus, Monacanthus, Cybium,
Spheroides and Sphyraena, while the other was quite contrary as in
Anguilla (M. ‘Vakeda).
The product of radiant energy of light of certain wave length and
the visibility of eyes to that light was called ‘Spectral luminosity” for
the same wave length; and when the spectral luminosity was calculated
by using the human visibility curve with the maximum displaced suit-
ably as a substitute for the true visibility curve of eyes of fish, it turned
FUNDAMENTAL STUDIES ON THE FISH LAMP 231
out that the ratio of the fish gathering rates for the two lights was pro-
portional to the ratio of the spectral luminosities of the two lights.
Moreover from the ratio of spectral luminosity to radiant energy, the
“visual efficiency” was calculated, and in the case of Spheroides rubripes,
green light showed the largest visual efficiency, that of blue light was
next to green, and that of red light was smallest.
Though radiant energy of red light was 22 times as much as that
of green light, its visual efficiency was no more than 1/62 of that of
green light (J. Konishi).
Studies on the influence of repeated experiments on the aggrega-
tion of fish to a fish lamp were carried out; the young Girella punctata,
which was repeatedly made at intervals of ten minutes, made clear
that the influence of a preceding experiment was held over to the suc-
ceeding one, while in the experiment of young Scomberomorus nipho-
nius made at intervals of 30 minutes, no such influence was seen, and
the fish gathering rates of Scomberomorus, Oplegnathus and Monacan-
thus under the stationary light attained maximum in a definite time,
and then became stabilized at this maximum value (H. Kobayashi).
The experiment of turning on and off at any intervals two lamps
which were situated inside the water tank (3 m. in length, 64 cm. in
width, 40 cm. in depth) was done. Aplocheilus latipes (fresh water
fish) and Girella punctata showed the greatest gathering rates to the
lamps, which had the most appropriate intensities for them when two
lamps were turned on and off. However, the gathering rates, as a whole,
decreased little by little in proportion to shortening of the interval
(T. Niki).
The gathering rates of Spheroides and Mugil show almost the same
tendencies of sectional distribution as the type U in the limited length
of water tank (3 m. in length, 25 cm. in width and depth) and the
light source set at the end of it, used in this experiment, the type U of
the curve of sectional distribution of fish in the tank is divided into two
meanings; and those are positive gathering rate which decrease expo-
nentially in proportion to the distance from the light, and negative
gathering rate which, on the other hand, increase exponentially to the
opposite side of the light. The value of the light intensity at which fish
gathering rates are highest was 55 lux in Spheroides; both in the day
and in the night, the values were 15 lux in the night and 87 lux in the
day in Mugil (S. Nagata).
The present writer further studied with K. Uno on the influence
of the moonlight on the gathering rates to the fish lamp as follows:
The relation between the moonlight and the fish lamp upon the
gathering rates of fishes has been studied in the laboratory and in the
232 EIGHTH PACIFIC SCIENCE CONGRESS
open sea, as no experimental studies had been carried out, although such
relations were commonly discussed.
Laboratory experiment:
In a black colored tank, 1 m. in diameter, 20 cm. in water depth,
a 20W electric bulb was set so as to throw its light horizontally in the
water, on one side of the tank called F-light, after fish lamp and the
other one, called M-light, which compared to the moonlight was at-
tached 2 meters above the water surface. The light showed 0.068 lux
on that surface as the light intensity of the full moon on the surface of
the sea was measured from 0.06 to 0.07 lux.
Under these equipments, the gathering rate of fish to the F-light
was calculated for fifteen minutes at water temperature of 13°—14°C in
the dark room.
From the experiments of the gathering rates of fishes to the F-light
under varying intensity of the M-light in different species of fish, it
was found that the gathering rates of Girella punctata had almost the
same in either one light or two lights, while those of Pempheris japonica
were more considerably decreased in the two lights than in one.
And the result of the experiment on Spheroides niphoblse coincided
with that of Pempheris in spite of change in the intensities of the M-
light. It was observed that the gathering rates of fishes decreased in the
field of F-light according to the increase of intensity of the M-light;
and the rate increased in the field of green color of the F-light and
decreased in the red of it.
From the experiments above mentioned, the relation between the
gathering rates of fish and spectral luminosities which were calculated
from the product of the relative radiant energies in place of the light
intensities and relative visibilities for light of the same wave lengths,
(Kawamoto and Konishi, 1952) will be shown as the following equa-
tion:
where Ga and Gb are the values of rates of fish gathered under the F-
light and the M-light except in the field of the former respectively, and
Ha and Hb are the spectral luminosities under the fields of the two
lamps.
Open sea experiment:
A rectangular net of 20 m. x 6 m. x 3 m. was let down off the coast’
about 200 meters from the shore near our Ichthyological Laboratory
and ten horse-mackerels (Trachurus trachurus L.) about 16 cm. in body
length and 30 gm. in body weight were set free in that net at the time
of each experiment.
FUNDAMENTAL STUDIES ON THE FISH LAMP 233
At one side of the net, a fish lamp which directed horizontally to-
ward the other side was fixed one meter under the water from the sur-
face and a 20W, 60W or 100W electric bulb was used as a light source
of the fish lamp, and attached to it was a green glass filter 18 cm. in
diameter which had a limit of transparency from 500 my to 570 my
and maximum wave length of transparency of 530 mu.
The weather was frequently stormy during the experiment, as this
study had to be carried out from November to February in 1950-1951,
and diificulties had often been experienced for observing the phenomena
in the roughing sea. The water temperature measured from 14.0° to
15.5°C in these experiments.
‘The numbers of fish which gathered in the area of light field with-
in three meters from the lamp were calculated as the rate of gathering
for twenty minutes in every thirty seconds.
In the dark night experiments, the gathering rate attained about
80% within the time of two minutes and 30 seconds after the light
was switched on, and continued its rate at the light source of 20W of
the fish lamp.
The rate of gathering in the night of the moon age of 9.8 decreased
to 77.8% as compared with the data of the rate of gathering in the
dark night and, moreover, decreased to 21% at the moon age of 10.7.
The rate became zero at the 11.8 moon age, and no reaction of
fish to light was seen.
As the light intensity of 11.8 moon age was almost equal to that
of 18.0 moon age, it might be supposed that the fish would not show any
reaction to the fish lamp in the period between those two ages.
From these experiments, observation was made that the conditions
of gathering rates of fish differed according to the kind of bulbs, 20W,
60W, or 100W respectively, and it was considered that the 20W electric
bulb was most adequate in the limit of the size of this experimental
net, since the rates of gathering became irregular in the light sources of
60W and 100W.
It turned out clearly that the effect of the fish lamp was influenced
by the moonlight from the results of experiments in the laboratory and
in the open sea; however, the authors concluded that the efficiency of
it might be kept in some limit by adjusting the strength of intensity
of the fish lamp. But the relation of those intensities has not as yet been
sufficiently studied, and it will be cleared in a later experiment.
In the course of these studies, it was also understood that the ef-
ficiency of the lamp was considerably influenced by facts such as the
tidal current, direction of wind, and temperature of the sea water, etc.;
and the relation of these factors to the lamp will be studied later as
those must never be passed over.
COACTION IN LAMP-COMMUNITIES
By Hirosu1 MAEDA
Shimonoseki College of Fisheries
Yamaguchi Prefecture, Japan
Besides many investigations relating to the fish-gathering lamp on
such items as the light source, condition of light in water, phototaxis
of fishes and the methods of fishing, there is an interesting ecological
article worked by Hardenberg (1935) on shoals assembling around the
lamp. The effect of the fish-gathering lamp is nothing but merely a
simple artificial change of the light, one of the physical environmental
factors, to gather fishes. Thus, the mechanism of gathering fishes is con-
sidered to be based primarily on the phototaxis of some animals. It
is, however, quite uncertain whether the behaviors of animals in the
natural environment, which appear as the results of complex inter-
action of many factors, may accord or not with those observed in the
laboratory under special experimental conditions, namely, only one in-
dividual or one sort of fish is treated. It is reasonably expected that
the coaction of fishes may be modified by light and that the existence
of different sorts of animals may cause the phototaxis for some fishes.
For instance, fishermen use “‘shirasu’’ (larval fish, particularly sardine
or anchovy) or mysids as food for fishes to keep the shoal stable under
the lamp; zoo- and phyto-plankton feeders, such as Engraulis and Sto-
lephorus, are changed into pure zoo-plankton feeders under the lamp
and take smaller planktonic crustaceans assembling around the lamp,
and some fishes showing the negative phototaxis in experimental con-
dition, many benthonic fishes and higher predators, may act photoposi-
tively under the lamp where many prey animals are assembling. Thus,
the coaction between fishes around the light under the natural condi-
tion must be investigated at first, when we research the cause of the
fluctuation found in caches by lamp method. ‘The effect of light upon
fishes from the synecological point of view will be understood correctly
solely when the interrelation of animals under the light is fully com-
pared with that under the non-light condition. However, I can here
refer only to the phenomenon observed under the lamp.
In the following, I wish to give first the outline of coaction of
lamp-communities taking the most complex case observed in Shira-
hama (Wakayama-ken) as an example, and then show briefly some
234
COACTION IN LAMP-COMMUNITIES ASN)
examples of more simple cases which are considered to lack some so-
cial components.
A. PREY AND PREDATORS COEXISTING WITH THE OBJECI FISHES.
The observations were made in the area near Shirahama situated
on the west coast of Kii peninsula and strongly influenced by a branch
of the warm current “Kuroshio.” Animals assembling around the lamp
are synecologically classified into the object, fishes, preys, and predators.
Reviewing the data obtained during a series of investigations on food
habits and behaviors of fishes around the lamp to find the niches of
main fishes in lamp-communities, the lamp-animals are classified into
the following five groups:
1) Prey animals: This group consists of Gammalid amphipods,
megalopae, mysids and Engraulis of Shirasu stage, and represents the
lowest class in the temporal communities formed artificially under the
lamp. It contains no producer or smaller preys nourishing the animals
mentioned above. Members of this group are eaten chiefly by the se-
condary predators, although a part of them serves as the food of the
primary predators.
2) Primary predators: This group consists of Stolephorus, En-
graulis and Pempheris, of which the former two are said to be zoo- and
phyto-plankton feeders in the natural environment, but are changed
into pure zoo-plankton feeders under the light. Stomachs of the most
examined individuals were, however, almost empty.
3) Secondary predators: ‘This group consists of medium- or large-
sized zoo-plankton feeders, e.g. carangids and mackerels. “These mem-
bers feed chiefly on the prey animals and occasionally on the primary
predators.
4) Tertiary, quaternary and end predators: The primary and se-
condary predators which form the chief object of the lamp fisheries are
dispersed from the light by the emergence of tertiary and higher pre-
dators. Consequently, fishermen hate their visits very much. Espe-
cially the end predators, which occupy the highest position in the food-
pyramid of the lamp-community, may be called the destroyers of the
lamp-community, since the fishes disappear completely at the appear-
ance of members of this group. The lower predators form compact
shoals and move along the circular rout around the lamp, perhaps along
the equi-luminous line, while predators of the higher degree usually
visit the lamp in a single individual, move across the equi-luminous
line and take food actively under the light. The tertiary predators are
composed of squids and Sphyraena, the quaternary predators of Tri-
chiurids. The end predators in shallower water are composed of Squa-
lus, Coryphaena and Dolphinus, of which the latter two are much
236 EIGHTH PACIFIC SCIENCE CONGRESS
rarer than the first, while those near the bottom are represented by
Epinepherus and its allies.
(5) Indifferent group: ‘This group consists of the fishes which
have no significant relation to other animals on account of their
meagre population, short staying time under the light, and the fact
that they seldom eat or are eaten near the lamp. Some members of
this group occupy the situation between the lamp fishes and those
not assembling around the light; some others show enormously strong
phototaxis, Crabs, Atherina, Cypserulus, Mugil, Euthynnus, Tylosu-
rus, Teuthis and Ostracion are the main members of this group. The
following four inclinations are deducible from the above-mentioned
classification.
1. The size of a lower rank is, in general, smaller than that of
the higher rank. The fishes of the younger stage belong to a rank
lower than that of its full-grown stage.
2. The fishes of the lower rank take the food lower than that of
the higher fishes.
3. The fishes of the lower food rank are controlled more strongly
by the light.
4. The fish with a stronger dispersing influence on the community
is placed in the higher rank.
Generalizing these inclinations, we may be able to determine the
niches of main lamp-animals as follows: (small planktons can not be
assembled by the light in the streaming tide) — smaller planktonic crus-
taceans (Oncaea venusta and Calanus) — larger planktonic crustaceans
(megalopae, Gammalid amphipods and Siriella) — Engraulis of Shirasu
stage — Stolephorus — Engraulis — (Clupeidae) — Pempheris — Carangi-
dae — Sphyraena — squids — Trichiurus — Squalus Coryphaena — Dol-
phinus.
The lamp animals and those not assembling around the light can
not be separated distinctly from each other, but they are connected
completely by the existence of many fishes showing various degrees of
tendencies to assembling around the light. The distance between these
intermediate fishes and the lamp-animals may be determined by the ~
stability of the shoal, coaction to other animals and other behaviors
of the former. ‘Thus, the primary predators assembling around the
light and the fishes of the same rank not assembling near the lamp are
continued which each other by a series of the following intermediate
fishes — Atherina — Cypserulus — Mugil —; in the secondary predators
the series is represented as — mackerel — Sarda — Euthynnus — (Kat-
suwonus) —; and in the tertiary predators it is — Tylosurus —. Similar
COACTION IN LAMP-COMMUNITIES 237
relations can be expected also in the benthonic fishes, although they can
not be ascertained easily.
If the above-mentioned relations are correct and of important eco-
logical significance, there must be a lot of phenomena reflecting these
relations distinctly. The social structure of the lamp community and
the arrival order of various animals near the lamp may be accepted as
good examples of these phenomena.
When the lamp is lighted, many animals assemble one after an-
other and after a certain time they attain a condition of equilibrium.
At this time the animals occupy their situations horizontally, perhaps
also vertically, from the nearest part of the lamp to the periphery ac-
cording to the following orders (several actual examples are given be-
low): — planktonic crustaceans — Engraulis of Shirasu stage — Engraulis
of grown stages — Carangidae — Sphyraena (22h. 25 min. June 23, 1950),
planktonic crustaceans — Engraulis of Shirasu stage — Pempheris — Ca-
rangidae — squids — (lh. 00 min. Aug. 6, 1950), planktonic crustaceans —
Stolephorus — Engraulis of grown stages — Pempheris — Carangidae —
Sphyraena (2h. 40 min. Aug. 6, 1950), planktonic crustaceans — Engrau-
lis of Shirasu stage — Stolephorus — Engraulis of grown stages — Sphy-
raena (19h. 45 min. Aug. 11, 1950). The arrangement of the situation of
the animals from the nearest part of the lamp to the periphery is quite
parallel to the order mentioned previously. This arrangement is called
the standard form, from which many modifications are derived by the
dispersive activity of the higher predators. When higher predators
are not so numerous or their predating activities are not so violent,
the spatial relations of lamp-animals are not changed, except for the
animals of the lowest rank of the community, which are unable to keep
their positions and are driven away from the central part [Stolephorus
— Carangidae — Sphyraena — benthonic fishes (vertically) or squids (ho-
rizontally) (4h. 05 min. June 24, 1950), Engraulis of grown stage — Stole-
phorus — benthonic fishes (vertically) or squids (horizontally) (4h. 10
min. Aug. 17, 1950), Stolephorus — Pempheris — Carangidae —- benthonic
fishes (vertically) or squids (horizontally) (Oh. 00 min. Aug. 6, 1950),
Carangidae — Sphyraena (vertically) or squids (horizontally) (23h. 05
min. Aug. 22, 1950)]. When the higher predators are numerous their
predating activities become more violent, the spatial relations of ani-
mals in the community are reversed; the central part is occupied by
animals of higher ranks[ Tylosurus — Carangidae — Pempheris — Engra-
ulis — squids (2h. 40 min. Aug. 23, 1950) and Tylosurus — Carangidae —
Stolephorus (2h. 00 min. Aug. 24, 1950)]. Lastly comes the case when the
predating is very violent. This time most animals are unable to ap-
proach the light, the community consists merely of the predators and
238 EIGHTH PACIFIC SCIENCE CONGRESS
some much weaker animals quite indifferent to the food habits of the
predators [planktonic crustaceans — Tetraodontidae — Trichiurus (19h.
20 min. Sept. 17, 1950), planktonic crustaceans — Engraulis of Shirasu
stage — Trichiurus (3h. 25 min. Sept. 18, 1950)]. During the observations
I have also recorded the order of arrival of main lamp-animals near the
lamp. ‘The order of animals, determined by the mode of frequency,
is as follows: planktonic crustaceans — Engraulis of Shirasu stage —
Atherina — Cypselurus — Engraulis — Pempheris — Stolephorus — Sphy-
raena — squids — Carangidae — Trichiurus. Squids contain some small
individuals which come to the light early and are considered to be-
long to the prey group. The order of arrival of squids as solely the ter-
tiary predators is much later. Although Sphyraena seems to come to
the light earlier than carangids in the order determined by the mode
of frequency: Sphyraena — squids -— Carangidae — Trichiurus, in actual
cases it and Trichiurus assemble to the light last. Whenever they visited
the light relatively earlier, no other animals could be expected under
the lamp after their arrival. Actually there was no case, in that the
carangid came to the light later than squids, Sphyraena and Trichiurus.
From these facts the order of arrival near the light may be determined
as follows: Carangidae — Sphyraena — squids — Trichiurus. Thus, the
order of arrival near the light is quite parallel to the order of food
rank and the spatial arrangement mentioned previously.
Successional changes are strongly affected by the dispersing acti-
vity and the order of arrival; those two facts are also related closely
with the rank of animals in the lamp-community described previously.
B. PREDATORS ABSENT.
At Murotsu, about 35 miles west of Kobe, the gray rock cods
(Sebastodes inermis) are gathered by scattered bait and angled up in the
daytime. At night, the acetylene lamp is placed near the rock not far
from the coast and the fishes gather around the lamp to eat the zoo-
plankton and Shirasu assembling around the lamp. ‘Then fishermen
angle for these fishes.
In the latter case, it has been said that the more preys are assem-
bled around the lamp the more fishes are caught. ‘The amount of
conger leptocepharus in preys is considered one of the key factors. Ac-
tually the stomach of the angled gray rock cod is filled with the zoo-
plankton and fry which are considered to be assembled to the lamp.
I have been told that the fishes hardly assemble in the daytime near
the rock where the lamp is put at night, even if scattered baits are
placed in the water. It is clear that the prey plays a significant role
and there are no predators of the fishes in the present case.
COACTION IN LAMP-COMMUNITIES 239
C. PREYS ABSENT.
As I have asserted the significance of the prey of the object fishes
so strongly that readers may feel a contradiction in the title of this
paragraph, there is a case lacking the prey of the object fishes in the
community. It must be understood, however, that the light is used in
previous cases to gather fishes in places where no fish is found in
swarms. In this case, however, the light is used to attract the fishes
in places where fishes are found in swarms.
In Harima nada, a part of the Inland sea west of Awazi Is., the
shoals of Engraulis are easily recognized on winter nights by the glim-
mering light brought about on the sea-surface by swimming Engraulis.
Fishing boats pursue the shoals and go across them, when the lamps
are lighted. ‘The fishes are scattered at first, but the shoals are soon
reformed and keep the circular movement around the light. In this
case, there is no influence of the lower ranks on the behavior of Engra-
ulis, although there are some cases when the larger fishes such as yellow
tails (Seriola quinqueradiata) appear and disperse the shoal formed
around the lamp. It is not certain whether these higher predators are
the fishes always swimming after the shoal before the lamp is lighted
or fishes assembled after the lamp is lighted; although the former sup-
position seems more reasonable than the latter from the observations of
Fngraulis shoals in the day time.
D. PREYS AND PREDATORS ABSENT.
At Ejima, about 10 miles SSW from Murotsu, Engraulis shoals rest
at night among the rocks near the coast. ‘These fishes assemble to the
light when a light of relatively weak intensity moves slowly along the
coast. In this case, the fishes assemble to the light so rapidly that no
effect of preys can be considered. Also the influences of other fishes are
not admitted, because the carangid and mackerel swim away to the outer
sea and yellow tails can not approach near the coast. There are found
some half-beaks (Hyporhamphus sajori) and flat-fishes (Paralichihys
olivaccus) mixing in the Engraulis shoal caught among the fishes in this
region by the light, but they are all of the indifferent group and scarcely
have any influence upon the shoal of Engraulis.
After many types of social structures of lamp-communities have
been discussed, it may be concluded that the mechanism keeping the
fishes near the light is based on the two factors, light and food-relations,
though these two factors are unable to be treated separately. “There
are some intermediate forms between the animals comprising prey ani-
mals and primary predators, whose behaviors near the lamp are pri-
marily regulated by light, and the animals comprising quaternary and
end predators, whose behaviors near the lamp are regulated by the
240 EIGHTH PACIFIC SCIENCE CONGRESS
preys. ‘These intermediate forms may be arranged as follows:—higher
primary predators being regulated more strongly by light than by their
preys—secondary predators being regulated by both factors almost equal-
ly—tertiary predators being regulated mainly by their preys, though
being affected also by light in some degree. ‘Thus the effect of the
light differs considerably according to the situations of the object fishes
in the ecosystem. The purse seining at Harima nada and the anchovy
fisheries at Ejima are the extreme instances using the light to allure
the fishes directly to the lamp by phototaxis; and the gray rock cod
fisheries at Murotsu is an extreme example using the light to gather the
preys of the object fishes.
The coactions in lamp-communities are strongly affected by the
fish fauna, habits of animals and the environmental relations in the
area; consequently they may be accepted as the reproduction of the
coactions of these ecological factors, which are regulating the cosmos
of the area spatially and at all times, and in a short time in a limiting
area. ‘Thus, the investigation of the lamp-communities seems appro-
priate to recommend as one of the most convenient methods of observ-
ing the coaction of animals in the natural condition in a certain area.
THE HAKE FISHERIES OFF THE WEST COAST OF CHILE
By Erik M. POULSEN
International Commission for the Northwest Atlantic Fisheries
St. Andrews, N.B., Canada
Since 1945 there has occurred a tremendous development of the
hake fishery in the Pacific along the coast of Chile. The catch of 1945
totalled only 11,000 tons, whereas in 1951 it was 44,000 tons or four
times as big. i
This big increase was mainly achieved through a change in the
methods of fishing. Whereas formerly hake fishery was only carried
out by Chilean fishermen working from small boats with nets or hooks,
in later years German fishing vessels have been called in carrying out a
modern fishery with trawls in order that the increased demand for hake
by the fish meal plants could be met.
This intense trawl fishing, until then unknown in Chile, caused
great concern not only among the Chilean fishermen, but also with the
Chilean fishery authorities.
Therefore, when I for half a year in 1951-52 worked as a fishery
expert in Chile, for FAO and the Chilean Government, I was asked
to pay special attention to the fishery for hake, Merluccius (Spanish
Merluza or pescada) and especially to provide for an assessment of the
stock of hake, to investigate if there were reasons for fear of overfishing.
It was by then known that two species of hake occurred in Chilean
waters, Merluccius gay: and M. australis. ‘Their areas of distribution
were however not known, nor was it known if one only or both species
were affected by the newly established trawl fishery. In the following
the term “hake’’ is used for M. gay: whereas the M. australis is named
“southern hake.”
The two species are very much alike. However, it was found that
the number of gill rakers on the lower arm of the first gill arch was
different, varying in the hake between 14-17 and in the southern hake
between 9-10. No overlapping in numbers was found.
The experimental trawlings carried out showed that the hake was
found only north of Corral and the southern hake only in the area
south of Puerto Montt and in the southern archipelago. It is possible
that a small overlapping of their areas occurs between Puerto Montt
241
GZ4Z, EIGHTH PACIFIC SCIENCE CONGRESS
and Corral. Only the hake is affected by the present trawl fishery, which
is carried out between Coquimbo in the north and Talcahuano in the
south.
Owing to the rocky nature of the Chilean continental shelf it is only
in very small, minute areas of the large coastal region between Coquimbo
and ‘Talcahuano that trawling could be carried out. This fact alone
makes it rather improbable that overfishing could occur through the
present trawl fishery.
The hake was found from ca. 20 to ca. 150 m. depth and in greatest
quantities between 50 and 150 m. In deeper waters deeper than 150 m.,
the trawl could not be operated. ‘The fact that the catch was far
smaller between 125-150 m. than between 50 and 125 m. shows, however,
that greater concentrations of hake at the bottom in deeper water can
hardly be expected.
The biological study of the hake carried out in connection with
the experimental trawling showed the following main results:
REPRODUCTION
‘The spawning season is very extended, lasting from the beginning
of October to the end of April. The material further indicated that
the long spawning season has two maxima, one bigger in October-
January and a smaller in April-May.
The length upon attaining maturity for the first time varies some-
what from south to north. Fifty per cent were found mature in the
southern area at a length of 37 cm, in the northern area already at 30
cm. ‘The males grow mature at a somewhat smaller size than the fe-
males.
GRowTH
Owing to a great number of individuals with accessory rings in
scales and otoliths, these gave only little help for the determination of
growth. However, measurements of large numbers showed distinct
peaks of the length curves and thus the length at the close of the first
to fourth year could be determined as follows:
1 year old—l6cm
2 years old—27cm
3 years old—38cm
4 years old—47cm
The growth of the females is only a little faster than that of the
males, the 3-year old females being 3-4 cm bigger than the males. Fur-
ther, the females grow to a far bigger size than the males, and probably
live longer. No males bigger than 52 cm were found; females, however,
HAKE FISHERIES OFF THE WEST COAST OF CHILE 243
were found rather frequently right up to sizes of 80 cm. It must in this
connection be borne in mind that the investigation only covered part of
the area of distribution, and that the difference in size between the sexes
in the material caught may be due to a different pattern of migrations
for the older year classes of each sex.
Foop AND FEEDING HapsiTs
According to the stomach contents, the hake is mainly feeding on
plankton animals; sardines, anchovies and various crustaceans. True
bottom animals, as worms and molluscs, were hardly ever found in the
stomachs.
In accordance with this feeding habit the hake undertakes diurnal
vertical migrations following the same migrations of the food animals,
shunning the upper layers of the sea during the day.
This habit of feeding on macro-plankton makes it possible for the
hake to live independent of the bottom. In this connection it is of in-
terest that bigger concentrations of hake can only be found on the
trawling grounds along the coast from September to May (in the spawn-
ing season). ‘Taking the feeding habits into consideration it is well pos-
sible that, apart from this period, the hake is living in the free water-
layers either over the fishing grounds along the coast or farther sea-
wards.
REGIONAL DIsTRIBUTION ACCORDING TO SIZE
It was the general opinion that in order to protect the young hake,
trawling should be prohibited in shallow coastal waters, and in fact
large areas of shallow water along the coast were closed to trawlfishing.
However, the investigations showed beyond doubt that the younger and
smaller individuals lived in deeper water; in the shallow coastal water
only large and medium-sized individuals were found. Thus for the pro-
tection of the growing hake, the prohibition of trawlfishing in shallow
water was of no avail.
MIGRATIONS
For the assessment of stock and for an accurate determination of
the probability of overfishing, a knowledge of the migrations is essential.
The investigations showed the following pattern of migrations:
As the smallest (youngest) bottom stages are found far away from
the shore, it is probable that the larvae live over this deeper water.
The scarcity of spawning and spent females in the catches on the coastal
fishing grounds indicates that part of the spawning is likely to occur
over deeper water. The first migration of the merluza is a drift of eggs
244 EIGHTH PACIFIC SCIENCE CONGRESS
or larvae out to deeper water. The second migration is the return of
the young individuals in the course of 2 or 3 years to the coastal waters.
The third migration is a movement back again to deeper water for
spawning. A fourth migration is the dispersal of the fish after spawning
(observed through the trawlfishing). As the spawning shoals are made
up of at least two or three groups, it is clear that these migrations occur
annually.
However, the fact that the biggest individuals (larger than 60 cm.)
are more numerous in deeper than in shallow water, shows that the
older merluzas do not return to shallower water. It is also quite possible
that the fact that males are not found in the samples to a length of
more than 52 cm is not due to the fact that the males do not attain a
larger size, but is caused by an earlier cessation of the shoreward migra-
tion than it is the case with the females.
These two points leave open the possibility or probability, that
there are concentrations of bigger merluza both male and female in
deeper waters still not touched by fishery, forming a reserve from whose
spawning activity recruitment of the merluza stock will continue without
danger from the fishery.
Finally we have the diurnal migrations of the merluza in search
for food towards the bottom at dawn and away from the bottom at
nightfall.
As far as assessment of stock is concerned, the investigations under
review have shown that the hake occur in great quantities off the Chi-
lean coast from Coquimbo in the north to south of Talcahuano, and
that only small patches of this vast region are touched by the trawl-
fishing in its present state. Further, the study of the migration has
shown (1) that for part of the year the hake is dispersed either in in-
termediate water layers far from the bottom or farther seawards where
it is not fished upon and (2) that part of the spawning occurs in off-
coastal regions where no trawlfishing is carried out.
These facts show that for the time being no danger of overfishing
of the stock is present. The areas not fished upon and the concentrations
of hake not touched by the fishery are so large that they constitute a big
reserve of hake to be drawn upon for the recruitment of the stocks
fished.
However, as a considerable expanding of trawlfishing for hake can
be expected in Chilean waters, and out of the consideration that “pre-
vention is better than cure’”—and in question of conservation of fish
stocks—far more easy than cure, it was recommended that certain mesh
regulations should already now be introduced in order to protect the
smaller and—from a commercial point of view—less valuable individuals.
HAKE FISHERIES OFF THE WEST COAST OF CHILE 245
In order to protect the Chilean fishery conducted by smaller craft
with nets and lines, it was further recommended that trawlfishing should
be prohibited in certain coastal areas especially fished in by these smaller
craft.
The present ground trawlfishing for hake in Chilean waters is
carried out only on the tiny patches of smooth bottom occurring in a
few places over the whole area and at day time only when the sunlight
causes the hake to concentrate at the bottom. The danger of overfish-
ing of the hake through this fishery therefore hardly exists.
A real danger to the hake stock can, however, be expected the mo-
ment the modern midwater trawling is introduced in Chilean waters,
making it possible for the fishing vessels to pursue the hake not only in
the short periods when it is concentrated on the bottom but also dur-
ing the diurnal migrations away from the bottom as well as during its
seasonal migrations away from the coastal grounds, i.e. during the whole
of its life.
In order to meet such a danger in the right way, a thorough knowl-
edge of the biology of the hake is an absolute necessity. The report
on the investigations therefore also contained a plan for further re-
searches aiming at such a complete knowledge to form the basis for
the judgement of what regulations of the fishery should and must be
introduced in order to conserve the stock and maintain the fishery at its
highest possible level.
REPORT ON THE ALGAE OF THE CHILEAN SEAS
By Hecror ETCHEVERRY-DAZA
Marine Biological Station
University of Chile, Montemar, Chile
The purpose of this brief report is to present a picture of the
Chilean algae flora, quoting its characteristic species, particularly those
which can be used as raw material or food.
An ecological rather than a systematic approach has been followed.
With regards to the commercially important algae the author has not
gone into details about the techniques applied for their utilization.
The Chilean algae flora extends along the western coast of South
America, from Lat. 18°22’S. down to Cape Horn. Within the Chilean
realm numerous islands are included. Important among them, because
of their size, abundance of algae and available phycological literature
are Juan Fernandez, Desventuradas (San Félix and San Ambrosio) and
Easter Island. In addition the Chilean Antarctic Region, limited by
the meridians 53° W. and 90° W. and the South Pole, should be con-
sidered. The Chilean algae domain extends therefore from tropical la-
titudes down to the South polar region.
From Arica to Chiloé the biological and physico-chemical condi-
tions (salinity, tides, temperature, light, physical nature of the sub-
stratum) are approximately uniform. From Chiloé to Cape Horn exist
numerous archipelagos, rocky coasts, waters with low salt content and
the greatest tide difference in Chile (up to 10 m.).
The Antarctic Region with high cliff characteristics, bottom de-
posits, temperature, salinity, marine currents, tides, ice, penetrations of
light, etc. have a particular and specific influence on the phycological
flora, characterized by endemisms and the abundance of calcareous
algae.
This paper should deal only with the first two referred regions,
in so much that the algae flora of the Antarctic has become well known
since Foster, in 1829, collected in Graham’s Land the first algae of the
region.
The Marine Biological Station of the University of Chile, located
at Montemar, have started a systematic and phytogeographic study of
the algae of the Chilean territorial waters. In the last few years, some
contributions on this subject, from the systematic and technical point
246
ALGAE OF THE CHILEAN SEAS 247
of view, have been published. Also the station has already assembled
a well stocked collection including specimens from the Chilean main-
land, its islands, and the Antarctic, as well as from various regions of
other continents.
The region from Arica to Cape Horn is a very rich one, both
in genera and species. There is a littoral rocky zone, beaten by the
constant and strong wave impact, with deep and shallow pools, and a
sublittoral zone where the rocks are cliff-like and covered by a veritable
belt of large-sized algae.
The author does not attempt to make a systematic list of all the
species, but will only refer to the most characteristic of the benthic Chlo-
rophyceae, Phaeophyceae, and Rhodophyceae of the continental shelf.
Among the species so far identified, some are cosmopolitan, and, in
the northern zone, there are elements common to the Peruvian flora.
The islands are characterized by their endemicity. Some of the large
Phaeophyceae species are also found in the waters off South Africa and
New Zealand.
A. In the littoral zone we distinguish:
1. An upper littoral belt, characterized by algae resistant both to
desiccation and to changes in salinity, particularly in the pools.
MYXOPHYCEAE
NOSTOCOCALES
Lyngbya confervoides C. A. Ag., on the rocks of the upper littoral
belt.
CHLOROPHYCEAE
ULOTRICALES
Enteromorpha bulbosa (Suhr.) Kitz.
E. compressa (L.) Grev.
E. intestinalis (L.) Link.
Eeyiinza. (e.) J. Ag:
Ulva lactuca (L.) v. rigida (Ag.) Le Jolis.
U. v. latissima D. C.
CLADOPHORALES
Chaetomorpha linum (Miller) Kutz.
Ch. aerea (Dilwyn)
Cladophora pacifica (Mont.) Kutz.
C. incompta Hook. f. et Harv.
C. subsimplex Kitz.
Spongomorpha arcta (Dilw.) Kutz.
248 EIGHTH PACIFIC SCIENCE CONGRESS
PHAEOPHYCEAE
; PUNCTARIALES
Scytosiphon lomentarius (Lyngby.) J. Ag.
RHODOPHYCEAE
BANGIALES
Bangia fuscopurpurea (Dilw.) Lyngby.
Porphyra columbina Mont.
P. {. Kunthiana Hamel.
2. A middle littoral belt, peculiar to sheltered beaches in which
there is an abundance of Phaeophyceae, Rhodophyceae and some Chlo-
rophyceae.
CHLOROPAYCEAE
SIPHONALES
Codium dimorphum Svedelius; forming a deep green velvet on ver-
tical cliffs.
PHAEOPHYCEAE
DICTYOTALES
Padina Commersoni Bory.
Glossophara Kunthi (C. A. Ag.) J. Ag.
PUNCTARIALES
Ilea fascia (Miill.) Fr.
Colpomenia sinuosa (Roth.) Derb. et Sol.
Endarachne Binghamiae J. Ag.
Scytothamnus australis Hook. f. et Harv.
Adenocystis utricularis (Bory) Skottsb.
SPHACELARIALES
Halopteris hordacea (Harv.) Sauv.
A. funicularis (Mont.) Sauv.
ECTOCARPALES
Ectocarpus stliculosus (Dilw.) Lyngb.
Pylaiella littoralis (L.) Kjellm.
RHODOPHYCEAE
GELIDIALES
Gelidium crinale (Turn.) J. Ag.
G. filicinum Bory.
G. lingulatum J. Ag.
NEMALIONALES
Chaetangium variolosum (Mont.) J. Ag.
CRYPTONEMIALES
Grateloupia Cutleriae Binder
Callophyllis variegata (Bory) Kitz.
ALGAE OF THE CHILEAN SEAS 249
Corallina chilensis Decaisne.
Hildebrantia Le Cannelliert Hariot.
GIGARTINALES
Schyzymenia Binderi. J. Ag.
Plocamium pacificum Kylin.
Tridaea laminarioides Bory.
I. obovata Kitz.
Gigartina Chamissoi (C. A. Ag.) J. Ag.
G. Chauvini J. Ag.
G. Lessonit (Bory) J. Ag.
G. Teedit (Roth.) Lamour.
Chondrus canaliculatus Grev.
Gracilaria lemanaeformis (Bory) Wome se 4 Bosse.
G. lichenoides (L.) Gmell.
Ahnfeltia Durvillaet (Bory) J. Ag.
Gymnogongrus furcellatus (C. Ag.) J. Ag.
CERAMIALES
Ceramium rubrum (Huds.) C. A. Ag.
C. Doze: Hariot.
Centroceras clavolatum (C. A. Ag.) Mont.
Polystphonia alscissa Hook. f. et Harv.
Laurencia chilensis D. T. Forti et Howe
Heterosiphonia Berkeleyi Mont.
RHODYMENIALES
Dendrymenia flabellifolia (Bory Skottsb.)
Rhodymenia corallina (Bory)
3. A. breakers belt, with large Phaeophyceae and some Rhodophy-
ceae belonging to the genera Gelidium, Iridaea and Rhodymenia.
Among the Phaeophyceae:
Lessonia nigrescens Bory.
Macrocystis integrifolia Bory, and
Durvillaea antarctica (Cham.) Hariot.
B. In the sublittoral zone there are areas covered by large sub-
merged Phaeophyceae belonging to the genera Lessonia, Macrocystis and
Durvillaea and of the deep water Rhodophyceae with species of Rho-
dymenia, Iridaea, etc.
PHAEOPHYCEAE
FUCALES
Durvillaea antarctica (Cham.) Hariot.
D. Harveyi Hook. f. et Harv.
250 EIGHTH PACIFIC SCIENCE CONGRESS
LAMINARIALES
Lessonia flavicans Bory.
L. nigrescens Bory.
Macrocystis integrifolia Bory.
M. pyrifera (L.) C. A. Ag.
DESMARESTIALES
Desmarestia herbacea (L.) Lamx.
D. Rossii Hook. f. et Harv.
D. Willit Reinsch.
EDIBLE ALGAE
Some algae of the Chilean coast have been utilized from olden
times in the feeding of man and animals. In the first place, it must be
mentioned, the Durvillaea antarctica fucaceae, whose area extends from
Valparaiso to the Antarctic region, is a very large alga with a strong
discoidal holdfast, short and strong, cylindrical stipe, prolonged in a
palmated frond, wedge-shaped at the base and branched at the top.
The people utilize the laminar part of the thallus and stipe, known by
the name of Ulte, Huilte or Coyofe. This alga is rich in iodine, con-
tains about 5.88 mg. per 100 grs. of dried algae.
Under the name of Luche or Luchi the chlorophyceae, Ulva lac.
tuca, and the rhodophyceae, Porphyra columbina, are consumed. ‘They
have the common characteristics of the laminar shape of the thallus
and the curly edges. Both are rich in glucids, iodine and vitamins.
The rhodophyceae Iridaea laminarioides, commonly called Yapin,
is used in Chiloé as pig fodder.
Cattle fodder is prepared in the central zone of Chile from species
of Macrocystis.
In addition there are other species of marine algae susceptible of
being utilized as human food or for fodder, belonging for example to
the genera Rhodymenia and Gigartina, also utilized in other parts of
the world.
The Algazos, name given to the algae cast up by the sea, are used
in Chiloé as fertilizer for potato crops. They include species of the gen-
era Enteromorpha, Ulva, and Macrocystis.
In the distant Easter Island, a Chilean possession, the natives eat
the chlorophyceae, Ulva lactuca which they call Kiroke and also a species
of Dictyopteris, a Phaeophyceae which they call Auke and consider de-
licious.
ALGAE OF THE CHILEAN SEAS 251
INDUSTRIAL ALGAE
The Algae utilized for industrial purposes are members of the Rho-
dophyceae and Phaeophyceae.
Three years ago the industrial utilization of these species began for
the production of phycocolloids, especially agar-agar. The species which
have given best results belong to the genus Gelidium (G. lingulatum
J. Ag. and G. filicinum Bory) ; they are found in southern Chile, from
Antofagasta to Talcahuano under the tide line, in rocky places, where
they are generally difficult to collect. Total yields vary between 11 and
ZOE.
Other Chilean agarophyte are: Gracilaria Greville, Gigartina
Stockhouse, Ahnfeltia Fries, and Gymnogongrus Martius.
Good production has been obtained with Gracilaria lemanaeformis
found from the Peruvian coast to the Island of Chiloé.
The Marine Biological Station of Montemar, with the purpose of
cooperating in the industrial utilization of marine products, has inves-
tigated the problems relative to the extraction of agar, from different
species of agarophyta algae inhabiting the coast and their chemical
composition.
The agar extracted from the Chilean species as regards quality is
equivalent to the best that can be imported; it is specially used in bac-
teriology and in the production of food commodities. It is also ex-
ported, principally to Argentina.
The large Phaeophyceae of the Chilean coast, which correspond to
the Laminaria of Europe, belong to the genera Lessonia, Durvillaea,
and Macrocystis. ‘here is an incipient industry producing alginic acid,
alkali-soluble ficocolloids, derived from poliuronic acid, at present in
great demand for industrial, chemical and food purposes. The species
tested in Montemar correspond to Macrocystis pyrifera, M. integrifolza,
Lessonia nigrescens, and L. flavicans and Durvillaea antarctica.
All these algae grow in the breakers belt and in the sublittoral zone.
They are partly uncovered during the low tide, which makes their har-
vesting easier, in spite of the rocky characteristics of the coast which
prevents the use of mechanized techniques.
The abundance in Chile of those species can only be compared to
that of Canada, Scotland and South Africa. Along the coast there are
numerous and large beds of Macrocystis, which ensure the possibility of
intensive exploitation.
The experiments carried out at the Montemar laboratory and at the
Inveresk Institute (Scotland), by a number of the Station, give a 20 to
25% content of alginic acid for the mentioned species and very com-
252 EIGHTH PACIFIC SCIENCE CONGRESS
mendable values for laminarin, manitol and fucoidin, all of which prod-
ucts are beginning to be in demand in the market.
The alginates industry disposes of abundant raw materials in Chile
to serve as the basis for the preparation of a number of medical, chem-
ical and food products.
On a small scale Chondrus canaliculatus (Ag.) Grev. instead C. cris-
pus is used for extraction of carragenin, and Macrocystis pyrifera, M.
integrifolia and Lessonia flavicans are used to produce kelp meal.
SELECTED LITERATURE
CUBILLOS-Moya, R. El] Agar-agar chileno. Fev. Biol. Mar., Univ. Chile, V.
e, Nos. 1-2, pp. 70-88.
ETCHEVERRY-DAZA, H. 1951. Generos Algologicos chilenos. I. Genero Les-
sonia Bory. 1825. Ibidem., V. e, Nos. 1-2, pp. 53-69.
LLANA, A. 1948. Primera Expedicion Antartica chilena. Algas Marinas.
Ibidem., V. 1, No. 1, pp. 19-31.
1948. Algas Industriales de Chile. IJbidem., V. 1, No. 2, pp.
124-131.
SKOTTSBERG, C. 1941. Communities of algae in Subantarctic and Antarctic
waters. Kgl. Svensk. Vetensk. Ak. Handl., V. 19, pp. 1-92.
1941. Marine algae Commuities of the Juan Fernandez Is-
lands, with remarks on the comparison of the flora. In The Natural
History of Juan Ferndndez and Easter Islands, V. 2, pp. 671-696.
TAYLOR, WM. R. 1939. Algae collected by the “Hassler”, “Albatross” and
Schmitt Expeditions. II. Marine Algae from Uruguay, Argentina, the
Falkland Islands, and the Strait of Magallanes. Pap. Mich. Acad. Sci.,
Arts, and Letters, V. 24 (1988), pp. 127-164.
1947. Algae collected by the “Hassler”, “Albatross” and
Schmitt Expeditions. III. Marine Algae from Peru and Chile. Ibidem.,
V. 31, pp. 57-90.
THE FISHERIES OF CHILE
By B. F. Osorto-TAaFraLi
Oficina Regional para Sudamerica Occidental
Santiago de Chile, Chile
INTRODUCTION
The coast of Chile extends from the tropics to near the Antarctic
region for a length (not including islands and channels in the far south)
of about 2900 miles, along the Southeast Pacific.
Chile is becoming aware of the wealth of her coastal waters. In-
creased action is being taken to utilize these natural resources to com-
plement the food intake of the population and also to develop national
brands for the domestic markets to replace formerly imported com-
modities and, in certain cases, for sale on the international market.
As in other Latin American countries where rapid progress is be-
ing made in the better utilization of their fishery resources, Chile is
consistently showing an important increase in the output of its marine
fisheries. From a total catch of about 30,600 metric tons in the pre-
war years, the production rose to 118,300 tons, or by about 386 per cent,
in 1952. This is due particularly to the meat shortage and also to the
encouragement of the fishing industry by both Government agencies and
private interests.
Should the demand of the domestic market increase or new foreign
markets be opened to Chilean fish and shellfish products, it is likely that
a great deal of expansion could take place. Not only could fresh fish
production be enlarged but processing would also become profitable for
some valuable species.
1. NATURAL CONDITIONS
Chile appears to possess all the natural advantages for the establish-
ment of a very important fishing industry, perhaps the leading one in
Latin America; a long and productive coast line, many valuable species
ot fish, molluscs and crustaceans, and a sea-going population which has
been engaged in fishing for many years.
Favorable oceanographic conditions, particularly along the Hum-
boldt current, are conducive to provision of varied marine species for
commercial purposes, some of which are virtually unknown in most
parts of the world.
254 EIGHTH PACIFIC SCIENCE CONGRESS
The marine fauna of the Chilean coastal waters fall into two major
biogeographical provinces. ‘The northern section belongs to the tem-
perate West South American or Peruvian-Chilean province, with its
northern boundary at Agujas Point (Peru) and with its southern ex-
treme in Chiloé Island, where the sub-Antarctic or Patagonian province
begins.
The narrowness of the continental shelf confines the productive
trawl fishery to limited areas between Quintero and Chiloé I., but the
pelagic or high sea fisheries, virtually untapped, constitute invaluable
potential resources.
Fish and shellfish are found in great abundance in Chilean waters
and are so regularly available generally as to form a secure and sustained
base for a greatly expanded one. Among the species represented are
tuna (albacore and yellowfin), bonito, swordfish, sardines, herring and
anchovies, cusk eel (the delicious “‘congrio’”’), mackerel, king crab, lob-
ster, shrimp, oyster, etc. From these, products that are in constant de-
mand in world markets may be derived. Some of the species mentioned
—sardines and anchovies, e.g.—may be taken in mass production fishing
at low cost for drying and salting to be marketed as a valuable food
product which keeps well, is highly concentrated and can be easily dis-
tributed.
2. LABOUR AND EQUIPMENT
a) Fishermen.
There are about 7500 men regularly engaged in fishing. The cen-
sus of fishermen as of January 1950 gives 7229 fishermen operating all
along the Chilean coast and 426 crewmen on fishing boats over 10 tons
working for canneries; in the 1943 census the number of fishermen was
given as 5517. In addition, the number of workmen in canneries and
processing plants is 3816. In total, there are 11,471 men engaged in
fishing and fish processing. In the Talcahuano region alone the number
of the fishermen amounts to 2000.
The fishermen of Chile appear to form a homogeneous group. The
great majority of them are hard working, enterprising, and intelligent.
Because of these qualities they are capable of mastering new techniques.
With expert instruction there is no doubt at all that they may be relied
upon to develop increasing productivity. Surveys indicate that the chief
problem among fishermen is lack of means to purchase adequate craft
and gear. The average income of fishermen ranges from 1000 to 2000
pesos monthly, but individually might vary from about 500 to 8000
pesos (official rate: 1 American dollar = 110 Chilean pesos).
FISHERIES OF CHILE 255
It is evident that with so low an income many fishermen do not
earn their livings and are forced to devote part of their time to other
jobs.
b) Craft.
In December 1951, out of a total of 4338 fishing craft used, approx-
imately 64 were engine driven vessels of medium size (10 to 200 gross
tons, including 12 whale catchers), 917 motorized small craft (most of
them with portable gasoline engines), and 3357 open boats with oar and
sail, representing 77 per cent of the total fishing fleet were in operation.
The census taken in 1943 recorded 385 motorized and 2554 non-motor-
ized vessels.
Almost all the present fishing fleet was built in Chilean yards from
domestic materials and by local labor. Since the inception of the trawl
fisheries in the early forties and the building of new processing plants,
several large steel trawlers and some wooden purse seimers were im-
ported, most of them from Belgium and Germany. ‘The local ship-
yards have also been active in building new power-driven craft. Un-
fortunately some of these large boats have been wrecked or lost at sea.
Present types of boats appear to be adequate enough to supply the
existent demand for fresh fish. However, due to the very low product-
ivity per man and year of the small non-powered craft and the increased
demand for raw material from the processing plants, both for canning
and fish meal, if production costs are to be maintained at an adequate
level, motorization of the fishing fleet is imperative and acquisition of
larger and modern craft is necessary for fishing in distant grounds to
supply fish varieties at lower price. Such boats could be built in Chilean
shipyards if technical assistance is provided.
©). Gear:
The amount of fishing gear in Chile has been estimated in 1945 as
including approximately 600 units of longlines (“palangre” or “espinel’’)
used almost exclusively for cusk eel (“congrio’”); about 400 gill nets
(“amalladeras” or “trasmallo’”) of different types; about 1000 harpoons
which account for practically the entire catch of swordfish; ring nets
(‘“boliche”) for bonito, sardine and anchovy, numbering 120; beach
seines (“chinchorros de playa”) of various types numbering about 250;
otter trawl nets, exclusively used in the hake fishing; trolling lines for
tuna fishing; lobster traps in Juan Fernandez Island; traps (‘“nasas’’)
for crabs and shrimp, and about 200 diving outfits used in the shellfish
fisheries.
256 EIGHTH PACIFIC SCIENCE CONGRESS
While the longline is still of great importance for cusk eel, {lounder
and croaker fishing, the otter trawl has become of increasing importance
in the recent years, in the fishing of hake or whiting, taking about 65%
of the total fish catch.
Almost all the nets used in Chile are made from domestic materials
and, although there is a lack of adequate fittings and cable, operations
are fairly efficient.
d) Investments.
Chile’s fishing industry was evaluated in June 1947 as representing
an investment of approximately 400 million pesos, distributed as follows:
Million pesos
Craft and gear 200
Processing plants 175
Fresh fish distributing and
marketing facilities 10
Others 15
Total 400
It is probable that, on account of recent developments, particularly
the severe inflation suffered by the country, the total investments in the
industry are now 100% higher, that is around 800 million pesos.
3. PRODUCTION
a) The Fishing Zones.
Chile can be roughly divided in respect of her marine fisheries, into
five zones, which from north to south are:
North: Provinces of Tarapaca and Antofagasta
North Central: Province of Coquimbo
Central: Province of Valparaiso and San Antonio
South Central: Province of ‘Talcahuano
South: Provinces of Valdivia and Puerto Montt.
The northern zone with Iquique, Antofagasta and ‘Taltal, is im-
portant because of its pelagic fisheries which include such species as
tuna, bonito, swordfish and pilchard, processed in the local canneries,
the largest in the couniry.
The north central zone supplies the immediate mainland as well
as the Santiago Market with the highest priced varieties of fresh fish,
viz: cusk eel (‘“congrios negro” and “colorado’”’), flounder, croaker,
mackerel, etc.
The central zone is the site of the large trawl fisheries centering in
Valparaiso and San Antonio. Hake is the species exploited, with about
64 per cent of the catch going to fish meal plants.
FISHERIES OF CHILE 257
The Talcahuano zone produces fresh fish, principally hake and
cusk eel, with part of the catch sold locally and the balance being
shipped by rail to Santiago; it also produces mackerel and sardine for
local canneries.
In the southern zone fishing is mostly of the subsistence type, but
being the richest in shellfish, these provinces contain most of the plants.
processing molluscs and crustaceans.
b) The Catch. (As indicated by Table I)
Fish landings have consistently increased since 1944. Figures for
previous years, while showing an upward trend evidence some fluctua-
tions. ‘Tie rather spectacular increase in the fish catch is due to the
development of the trawl fisheries for hake, offshore along the central
section of the country (areas Valparaiso—San Antonio, and Talcahuano).
Shellfish landings manifest wider fluctuations than fish landings but
there is also an apparent trend to rise during the past few years.
TABLE I
CHILE
FISH AND SHELLFISH LANDINGS, 1931 To 1951
(In Metric Tons)
YEAR FISH SHELLFISH TOTAL
1931 11,836 5,180 17,016
1932 14,204 8,982 23,186
1933 18,572 8,623 PAT USI)
1934 17,680 8,207 25,887
19385 21,104 7,676 28,780
1936 27,579 7,282 84,861
1937 28,778 7,909 36,687
1938 24,114 6,458 30,572
1939 28,912 7,642 36,0504
194 27,094 11,216 88,310
1941 29,017 8,363 37,380
1942 24,086 8,128 32,214
1943 80,999 9,549 40,548
1944 29,023 10,778 39,801
1945 32,623 14,401 47,024
1946 39,815 21,128 60,943
1947 45,6938 14,378 60,071
1948 47,396 17,328 64,724
1949 60,375 15,871 76,246
1950 69,337 17,529 86,866
1951 73,106 19,931 93,037
1952 94,370 23,916 118,286
Source: Direccién de Pesca y Caza, Ministerio de Economia y Comercio, Chile.
258 EIGHTH PACIFIC SCIENCE CONGRESS
In 1952, ten species (Table II) formed about 92 per cent of the
total fish catch, with a single species, hake, accounting for more than
68 per cent of the total fish production.
c) Disposal of the Catch.
On the basis of the 1951 figures Table III has been prepared giving
the utilization of the catch and for each item the weight of raw ma-
terial and of the edible portion. The latter data are needed to estimate
the per caput consumption.
There is a great spread in production per capita, from the lowest,
3 kilos in the southern zone of Puerto Montt, to 20-22 kilos in the
northern districts. It shows that the production in the middle zones
is not large enough to satisfy the demand of its large urban areas. In
spite of the commerce between the zones which should help to distribute
fish caught more equally according to the population, there seems to
be big differences in fish available for domestic consumption between
the various zones. The largest export of fresh fish takes place from the
Talcahuano zone, from which a large proportion of its production of
fresh fish is shipped, mainly to Santiago. ‘This reduces quantities avail-
able for local consumption in this big fishery zone considerably. An
influencing factor when considering fresh fish available for the domestic
market is the season of the year. aking the most important fish, Mer-
luza is caught in only four months, from August to November, and
50% of Sierra in the four months from January to April. Since 50%
of fish consumption is in fresh fish, it is obvious that, if consumption is
to increase, consuming centres must have better storage and distribution
facilities.
The Commercial Fisheries in all Latin America, but particularly
in Chile, are generally slow to improve products or to develop new
techniques, to exploit untapped resources, correct wasteful fishing me-
thods or to utilize their raw materials with economical possibility. “This
backwardness is probably the consequence of the very diffused char-
acter of the fishing industry, ordinarily comprising small individual
enterprises widely scattered along extensive coast lines and involving
great diversity of local fisheries based on notoriously unstable supply.
4. VALUE OF THE CATCH
The value of the catch in 1952 as paid to the fishermen has been
estimated at 589 million pesos; 432 million for fish and 157 million for
shellfish. Consumers paid around 1250 million pesos for fresh fish and
shellfish and about 750 million for processed fish, making a total value
paid by the consumers of about 1.52 billion pesos.
259
FISHERIES OF CHILE
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‘260 EIGHTH PACIFIC SCIENCE CONGRESS
TABLE III
CHILE
UTILIZATION OF THE CATCH IN 1951
(In Metric Tons)
LANDINGS PERCENTAGE EDIBLE PoRTION
Fish
Fresh, whole 36,680 50.2 19,774
Fresh, filets 316 0.4 136
Dried Soll 0.5 88
Salted 35 0.1 5
Smokea 224 0.3 150
For meal 27,376 37.4 BRST
Canned 8,188 Blea] 3,029
| Total 73,106 100.0 29,265
Shellfish
Fresh 12,684 63.6 1,569
Canned 7,247 36.35 1,224
TOTAL 19,931 100.0 2,793
GRAND TOTAL 93,037 32,058
Source : Estimated from data coiected by the Direccién de Pesea y Caza, Ministerio de
Economia y Comercio, Chile.
* Utilized in poultry and milk cow feeding.
Exports were valued in 1951 at about 45 million; imports of fish
commodities were 3 million, and imported supplies and materials for the
industry (not including the value of the large trawl vessels brought to
Chile) 2n additional 25 million. It is estimated that the foreign ex-
change balance for the fishing industry is about 50 million pesos an-
nually.
5. WHALING INDUSTRY
Two Chilean companies engage in whaling. ‘The larger is the
“Compania Industrial” with its principal offices in Valparaiso; the other,
which is quite small, the “Compafiia Pesquera y Commercial de Macaya
Hermanos”, is established in San Vicente, Talcahuano.
The large firm has six whaling vessels and a shore station at Quin-
tay, not far from Valparaiso. ‘The whaling operations of this company
were begun during the last war to provide substitute materials for tal-
low and other scarce fats in its manufacturing processes. In 1951, this
company caught and processed 1096 whales (735 sperm whales, the
balance being baleen whales, chiefly finback—Table 1V).
FISHERIES OF CHILE 261
TABLE IV
WHALES CAUGHT IN CHILE
1943 To 1951
1 2 3 4 5 6 7
YEAR soISHES EBLUEL FInNBACK HUMPBACK SER eae TOTAL
1948 1 iL 13 — 128 -— 143
1944 — 3 49 38 363 —- 418
1945 -— 41 65 el 366 —- 483
1946 ~- 11 238 5 340 1 595
1947 — 22 90 15 720 2 849
1948 — 85 289 5) 731 6 1,116
1949 — 18 209 3 680 — 991
1950 -—— 43 273 4 773 — 1,093
1951 — ta 279 3 735 2 1,096
1—Balaena australis
2.—Balaenoptera musculus
3.—Balaenoptera physalis
4.—_Megaptera nodosa
5.—Physeter macrocephalus
6.—Balaenoptera borealis
Source: Direccidn de Pesca y Caza, Ministerio de Economia y Comercio, Chile.
The baleen whales yielded 721 metric tons of oil and the sperm
whales 2600 metric tons, a total oil production of 3321 metric tons for
this company, whose whaling activities are an adjunct to its extensive
and diversified soap and manufacturing activities. Over 90% of this
concern’s Output is used in the manufacture of soaps, the remainder
(baleen oil) goes into its production of margarine. The carcasses are
used in the fish meal and bone meal manufacture.
The smaller company owns a catcher which operates along the
central and southern Chilean coast. ‘The 1949 production was 900 bar-
rels (152.4 metric tons) of baleen whale oil and 2301 (84.8 metric tons)
of sperm whale oil. When this firm at Talcahuano cannot sell its pro-
duction to the Compania Industrial for hydrogenation and use in the
latter firm’s soap factory, the Talcahuano firm sells its production to
small soap factories located in the south of Chile.
6. PROCESSING INDUSTRIES
Fish have been processed in Chile for many years, but on a limited
scale. During the past fifteen years, however, considerable activity has
taken place. In 1950, 56 fish processing industries with a capital of
350 million pesos were in operation.
262 EIGHTH PACIFIC SCIENCE CONGRESS
Refrigeration:
Although a number of refrigeration plants exist, these generally
lack modern machinery and employ sub-standard methods. The role of
refrigeration in the fishing industry is not yet thoroughly understood.
Ice, chiefly because of the present high prices, is little used by the fish-
ing industry. ‘The proximity of the fish producing areas to the main
markets does not seem to require the more expensive methods of pre-
servation of fish, such as freezing.
Salteries:
Salting and drying of fish received considerable impetus during the
last war, chiefly for export. Production costs have been high, and for
this reason comparatively little salt fish is consumed in Chile. The so-
called “bacalao de Juan Fernandez’ (actually a grouper) is one of
several species which is salted and dried. In addition, small amounts
of hake, shark, elephant fish and cusk eel are dried; tuna, herring, sar-
dine and anchovy salted; and swordfish, snake mackerel, herring, sardine,
anchovy hake and smelt smoked. In 1951 about 375 tons of fish were
dried and salted, and 224 tons smoked. The resultant products were
90 and 5 tons respectively.
Cannertes:
Canning started in Chile around 1865. In 1946 there were some
20 canning plants having an approximate declared capital of 40 million
Chilean pesos. By 1950 the number of fish canning concerns increased
to 56 with an active capital of 350 million pesos. These canneries are
scattered from Arica in the far north to the extreme south in Punta
Arenas on the Strait of Magellan. The canneries are concentrated in
the following areas: ‘Tarapaca—Antofagasta, Valparaiso, Talcahuano,
Puerto Montt, Calbuco, and Punta Arenas. From the standpoint of
production the Tarapaca—Antofagasta areas and the Talcahuano area are
the major centres of canned fish production, processing respectively
6,700 and 17,900 tons of raw material.
Exact statistics of Chile’s canned fish are not available, but the total
figures give an idea of the steady rise in production. In 1936, around
1000 tons net of canned fish and shellfish were produced; 1951 fish
pack, chiefly sardines, tuna and herring, amounted to a net weight of
about 3425 metric tons.
Pesquera Iquique, S.A., with fish-freezing plant, plenty of refrigerated storage and tuna
and sardine canning, owns the most modern and best equipped fish plant in all Chile, located
in Iquique. In addition, there are Sociedad Industrial Pesquera de Tarapaca (elaborating the
renowned brand “Cavancha’’), with plants in Iquique and Taltal; Jorge Cerda’s plant “El
Buen Gusto” in Arica; Sociedad Pesquera Industrial Pacifico, in Iquique; Compaiiia Industrial
Pesquera and Mateo Zlatar’s plants, in Antofagasta; Industrias Pesqueras Guayacan in Co-
quimbo; Sociedad Italo-Portuguesa “Sipol’? in Valparaiso; Jorge Sarquis’ Sociedad Pesquera
“Qurbosa”’ Conservas y Productos Pesqueros S.A.; and Meekes and Saelzer in Taleahuano—San
Vicente dre the largest fish canneries in the country, whose combined output exceeds 75% of
the entire canned fish production.
FISHERIES OF CHILE 263
Shellfish canning is centered in the southern zone. In 1951 twenty
canneries were in operation, of which eleven are located at Calbuco
Island; another five farther south and the balance in Punta Arenas. Six-
teen canneries produced in that year 106,650 cases with an average of
6,660 cases per cannery, the largest output of a single cannery being
18,000 cases of finished product. A standard case of canned shellfish
contains 48 cans of 240 grams net each. The net output amounted to
1225 metric tons.
The present fish canning industry, with few exceptions, does not
employ modern machinery for efficient production methods. Costs,
therefore, are relatively high. Although buildings are usually good,
equipment, layout, working space arrangements and labour saving de-
vices are deficient. Machinery and other equipment, in general, are ob-
solete. Among the problems confronted by the Chilean fish processing
industry, in common with other Latin American countries, are the dif-
ficulty of acquiring new equipment to replace obsolete machinery, the
difficulty of obtaining foreign hard currency for cans, and the low
standard of cans manufactured locally. In fact, containers are often
made by the cannery and this practice has led to cans of sub-standard
quality, a great divergence of sizes and added overhead expenses.
It is obvious that the Chilean canning industry with modernization
and expansion will be capable of producing a much greater pack at
lower costs than those prevailing at present. Increased production is
dependent on the amount of tin plate available and of export markets
to absorb the output. The most logical and readily available markets
are those of other Latin American countries, but this outlet has not yet
been utilized. United States importers maintain that high cost of trans-
portation and difficulties of shipping make the venture of importing
Chilean canned fish to the United States almost unprofitable. Moreover,
production costs are at present abnormally high and Chilean canners
are not in a position to capture any significant part of the world’s market
for commodities such as tuna and bonito. However, exports of canned
fish and shellfish have risen from 112.4 metric tons in 1948 to 935.3
tons in 1951. It seems that the crustaceans and molluscs pack could
find a good place in foreign markets.
Fish meal:
Annual production in two modern plants, one with a capacity of
10 tons per hour, located in San Antonio and several small or crude
installations at the canneries, is estimated in 1951 at about 5,800 tons.
The majority of the raw material used is hake obtained by trawling
in the near fishing grounds. With a low oil content the hake is not
264 EIGHTH PACIFIC SCIENCE CONGRESS
suitable for oil production. It appears that good possibilities exist for
expansion of fish meal production both from wastes and from direct
fishing. Nevertheless, the profitability of fish meal production in Chile
by direct fishing remains to be seen. Cattle and poultry raising use
almost all the domestic production of fish meal.
Fish oil:
Production of industrial fish oils in Chile is still very limited. Not
more than 100 metric tons are estimated to be produced annually. How-
ever, this output is subject to increase as oil extraction proceeds in the
fish meal plants already in operation and the new ones under construc-
tion.
Vitamined oils:
Assays of samples of fish liver from Chilean waters indicate that
rich sources of vitamin “A” are available. Reported 1951 production,
chiefly of low potency oils, was about 29,700 liters. Present output is in
the neighborhood of 120 billion International Units, derived from about
275 tons of liver. Different species of shark and also tuna supplied the
raw material.
7. FREsH WATER FisH
The indigenous fish fauna of Chilean lakes and rivers is exception-
ally poor, particularly regarding edible species. The once abundant
smelt (pejerry — Basilichthys microlepidotus), native trout (trucha
criolla — Percichthys trucha), and catfish (bagre de agus dulce — Nema-
togenys inermis), as well as the small farionelas or peladillas (Haplochi-
ton spp.), were overfished in the measure that human settlements ex-
panded, with the result that, at present, these species are on the verge
of extinction.
Since 1905, the fisheries administration implemented an ambitious
programme of restocking Chilean fresh waters with species such as the
European salmon and trouts, the North American rainbow and steel
head trouts and the Alaskan salmon. ‘These activities were continued
for a number of years and, with the exception of the European and
the North American salmons which acclimatization apparently failed,
the other species were successfully established. In more recent years
this planting with foreign species was expanded to new areas and other
species, such as the valuable Argentinean smelt (Odonthestes bonar-
iensis), were introduced. It is interesting to report that all these ac-
climatized species grow in Chilean waters to a larger size than in the
original countries. However, the utilization of these stocks is mainly
for sportive purposes,
FISHERIES OF CHILE 265
SELECTED BIBLIOGRAPHY
ALARCAO, J. 1953. Present Status and Prospectives of the Fishery Industry in
Latin America. F.A.O. Fisheries Division. 31 pp. mimeographed. Food
and Agriculture Organization of the United Nations, Rome, Italy.
HERNANDEZ-PoNCE, M. 1953. Informaciones Estadisticas sobre Pesca. Direc-
cién de Pesca y Caza. pp. 57. Valparaiso, Chile.
Howarp, G. V. and GopFREY, E. 1951. A Summary of the Information on the
Fisheries and Fisheries Resources of Latin America. F.A.O. Fisheries
Division. 262 pp. mimeographed. Food and Agriculture Organization of
the United Nations, Washington, D.C.
LcoBELL, M. J. 1951. The Development of the Fishery Resources in Chile.
Proc. U.N. Sci. Conf. on Conservation and Utilization of Resources. Vol.
VII, Wildlife and Fish Resources. pp. 41-44. United Nations. Dept. of
Econ. Aff., New York. .
LOBBLL, M. J., et al. 1947. The Fisheries of Chile: Present Status and Future
Possibilities. Report of the U.S. Fisheries Mission to Chile. 1207 pp.
(typed), illustr. and appendixes. U.S. Dept. of Interam. Fish and Wild-
life Service, Washington, D.C.
MontTtT, M. 1949. La Pesca Industrial en Chile. 134 pp. Valparaiso, Chile.
Myers, G. S. 1950. The Fish Fauna of the Pacific Ocean. Proc. 6th Pacific
Set. Congr. Vol. 3. pp. 201-210. Univ. of California Press, Berkeley
and Los Angeles, Calif.
OSsORIO-TAFALL, B. F. 1951. Better Utilization of Fishery Resources in Latin
America. F'..A.O. Fisheries Bulletin. Vol. 4, No. 4, pp. 3-25. Food and
Agriculture Organization of the United Nations, Rome, Italy.
. 1952. Report on the Fisheries of Chile. 51 pp. mimeographed.
F.A.O. Regional Office for Western South America, Santiago, Chile.
POULSEN, E. M. 1952. Report to the Government of Chile on Food Fishes of
Chile. F.A.O. Report No. 45. pp. 72, illustr. Food and Agriculture
Organization of the United Nations, Rome, Italy.
PRELIMINARY LIST OF CHILEAN FISHES AND THEIR
VERNACULAR NAMES
By FERNANDO DE BUEN
FAO Fisheries Expert
Technical Assistance Program, Chile
The author has devoted six months, as an FAO Fisheries expert,
surveying fishery potentialities along the Chilean coast. While this
survey has been concentrated on commercially important species, during
the trips made aboard fishing boats, a number of interesting species
were caught and identified.
In this preliminary note some changes have been introduced re-
garding the nomenclature and taxonomic status of the species recorded
in Chilean waters. ‘This matter will be discussed in the author’s final
report to FAO.
On the basis of the existent recording literature and of my personal
observations, a list has been compiled including all the species of fish,
sensu latu, known to be resident in Chilean fresh water and coastal
waters, and also those migrants that seasonally approach the littoral of
the mainland, the off shore waters and the distant islands. The names
marked with an asterisk refer to species identified by the writer.
For the sake of simplification the following notations are used:
N., C., and S. indicate respectively Northern, Central and Southern
Sections of Chile.
JF refers to Juan Fernandez Island.
SFA to San Felix and San Ambrosio Islands.
P to the Easter Island (Isla de Pascua).
I MORDACIIDAE
1. Geotria australis Gray Lamprea, lamprea de bolsa.
(C.S.)
II EPTARETIDAE
2. Polistotrema polytrema (Girard) (C.S.)
3. Polistotrema decatrema (Regan) (C.S.)
III MYXINIDAE
4. Myxine tridentiger Garman (C.S.)
5. Myxine affinis Giinther (S.)
IV HEXANCHIDAE
6. Hexanchus griseus (Bonnaterre) Tiburon. (C.S.)
7. Heptranchias perlo (Bonnaterre) Tiburon. (C.)
266
CHILEAN FISHES AND THEIR VERNACULAR NAMES 267
V ISURIDAE
8. Isurus oxyrinchus Rafinesque (N.C.S.)
9. Lamna nasus (Bonnaterre) (C.S.)
10. Carcharodon carcharias (Linnaeus) Tiburon. (S.)
VI CETORHINIDAE
*11. Cetorhinus maximus (Gunner) . .» Tiburén gigante. (C.)
VII ALOPIDAE
12. Alcpias vulpinus (Bonnaterre) Pez zorro. (N.C.S.)
VIII SCYLIORHINIDAE
13. Cephaloscyllium ventricosum
(Garman) (Chile).
14. Halaelurus bivius (Smith) Pintarroja. (C.S.)
*15. Halaelurus chilensis (Guichenot) Pintarroja. (N.C.S.)
IX TRIAENODONIDAE
*16. Mustelus mento Cope Tollo. (N.C.S.JF)
*17. Mustelus maculatus (Kner y Stein-
dachner) Tollo. (N.)
18. Triaenodon nigricans Philippi (SFA)
X EULAMIIDAE
19. Galeorhinus chilensis (Perez Canto) Cazon. (C.S.)
* 20. Prionace glauca (Linnaeus) Azulejo. (N.C.S.)
21. Eulamia philippi Fowler (N.)
22. Eulamia robusta (Philippi) (N.S.)
XI SPHYRNIDAE
23. Sphyrna zygaena (Linnaeus) Pez Martillo. (N.)
XII SQUALIDAE
24. Scymnodon macracanthus (Regan) (S.)
25. Etmopterus paessleri Ldnnberg (S.)
26. Etmopterus granulosus (Ginther) (S.)
27. Squalus fernandezianus Guichenot Tollo. (C.S.JF)
XIII SQUATINIDAE
28. Squatina armata (Philippi) (N.C.S.)
XIV RHINOBATIDAE
29. Tarsistes philippi Jordan (N.C.S.)
XV RAJIDAE
30. Raja flavirostris Philippi Raya. (N.C.S.)
31. Raja magellanica Steindachner Raya. (S.)
32. Raja brachyurops Fowler Raya. (S.)
33. Psammobatis scobina (Philippi) Pequén. (N.C.S.)
34. Psammobatis lima _ (Poeppig) Trucha de mar. (N.C.S.)
XVI DASYATIDAE
35. Urotrygon chilensis (Giinther) (Chile)
36. Urobatis marmoratus (Philippi) (C.)
268
37.
38.
39.
* 40.
* Al,
A2.
* 43.
* 44,
* AD,
* 46.
* 47,
48,
49,
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
EIGHTH PACIFIC SCIENCE CONGRESS
XVII MYLIOBATIDAE
Aetobatus peruvianus (Garman) Aguila de mar. (N.)
Rhinoptera chilensis (Philippi) Aguila de mar. (N.)
XVIII MOBULIDAE
Mobula tarapacana (Philippi) (N.)
XIX TORPEDINIDAE
Discopyge tschudu Heckel Templadera. (N.C.S.)
: XX CALLORYNCHIDAE
Callorhinchus callorhinchus (Linneaus) Peje Gallo. (N.C.S.)
XXI CLUPEIDAE
Clupea fueguensis Jenyns Sardina. (S.)
Clupea bentincki Norman Sardina, sardina anchoa.
(C.S.)
Spratella nov. sp.? Sardina, sardina anchoa.
(C.S.)
Sardinops sagax sagax (Jenyns) Sardina espafiola. (N.C.)
Ethmidium maculatum (Valenciennes) Machuelo, machete. (N.C.)
XXII ENGRAULIDAE
Engraulis ringens Jenyns Sardina, sardina bocona,
anchoveta, chicora. (N.C.S.)
XXIII APLOCHITONIDAE
Aplochiton taeniatus Jenyns Peladilla. (S.)
Aplochiton zebra Jenyns Peladilla. (S.)
\Aplochiton marinus Eigenmann Peladilla. (S.)
XXIV STOMIATIDAE
Stomias atriventer Garman (Deep-sea).
XXV IDIACANTHIDAE
Indiacanthus niger Regan (Deep-sea).
XXVI GONOSTOMIDAE
Cyclothone signata Garman (Deep-sea).
XXVIII MAUROLICIDAE
Maurolicus mulleri (Gmelin) (Deep-sea).
XXVIII GALAXIIDAE
Brachygalaxias bullocki (Regan) Puye. (S.)
Galaxias attenuatus (Jenyns) Puye. (S.)
Galaxias gracillimus (Canestrini) Puye. (S.)
Galaxias maculatus (Jenyns) Puye. (S.)
Galaxias alpinus (Jenyns) Puye. (S.)
Galaxias globiceps HEigenmann Puye. (S.)
Galaxias platet Steindachner Puye. (S.)
XXIX CHLOROPHTHALMIDAE
Chlorophthalmus glacilis Giinther (JF)
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
Ute
78.
Usb
80.
81.
82.
83.
84,
85.
86.
87.
88.
89,
CHILEAN FISHES AND THEIR VERNACULAR NAMES 269
XXX MYCTOPHIDAE
Myctophum affine (Liitken)
Myctophum tenisoni Norman
Rhinoscopelus cocco (Cocco)
XXXI CHARACIDAE
Cheirodon pisciculus Girard
Cheirodon galusdae Eigenmann
Cheirodon australe Eigenmann
(Deep-sea).
(Deep-sea).
(Deep-sea).
Pocha, pochita. (Fresh-
water).
Pocha, pochita. (Fresh-
water).
Pocha, pochita. (Fresh-
water).
XXXII DIPLOMYSTIDAE
Diplomyste chilensis (Molina)
XXXIII ARIIDAE
Netuma barbus (Lacepede)
XXXIV PYGIDIDAE
Hatcheria maldonadoi Eigenmann
Hatcheria bullocki Fowler
Hatcheria macraei (Girard)
Pygidium chiltoni Eigenmann
Pygidium areolatum (Valenciennes)
Pygidium maculatum (Valenciennes)
Nematogenys inermis (Guichenot)
XXXV LORICARIIDAE
Ancistrus erinaceus (Valenciennes)
XXXVI MURAENIDAE
Muraena appendiculata (Guichenot)
Gymnothorax porphyreus (Guichenot)
Gymnothorax weineri Sauvage
Gymnothorax chilensis (Giinther)
Gymnothorax modestus (Kaup)
Tollo, bagre de agua dulce.
(Freshwater).
Bagre marino. (S.)
Bagre. (Freshwater).
Bagre. (Freshwater).
Bagre. (Freshwater).
Bagre. (Freshwater).
Bagrecito. (Freshwater).
Bagre. (Freshwater).
Bagre. (Freshwater).
(Freshwater).
Murena, culebra de mar. (C.)
Murena, culebra de mar.
(JF)
Murena, colebra de mar.
(Chile).
Murena, colebra de mar.
(Chile).
Murena, colebra de mar. (C.)
XXXVII OPHICHTHYIDAE
Ophichthus ater Peters
Ophichthus dicellurus (Richardson)
Ophichthus remiger (Valenciennes)
Ophichthus pacifict (Gunther)
Ophichthus callaensis (Gtinther)
XXXVIII CYEMIDAE
Cyema atrum Giinther
Anguila. (Chile).
Anguila. (N.C.)
Anguila. (C.)
Anguila. (N.C.)
Anguila. (N.C.)
(JF)
270 EIGHTH PACIFIC SCIENCE CONGRESS
XXXIX NOTACANTHIDAE
9). Gigliolia moseleyi Goode y Bean (Deep-sea).
XL SCOMBERESOCIDAE
* 91. Scomberesox equirostrum Le Sueur Agujilla, punto fijo. (C.JF)
XLI HEMIRAMPHIDAE
92. Hemiramphus phurcatus Philippi Pez aguja. (P.)
XLII EXOCOETIDAE
93. Hxocoetus volitans Linnaeus Pez volador. (N.)
94. Cypsilurus lineatus (Valenciennes) Pez volador. (JF)
XLIII MURAENOLEPIDAE
95. Muraenolepsis orangiensis Vaillant Ss)
96. Muraenolepsis microps Lonnberg . (S.)
XLIV GADIDAE
97. Saliota australis (Ginther) (S.)
98. Physiculus marginatus (Ginther) (S.)
99. Lotella fernandeziana Rendahl (JF)
100. Laemonema multiradiatum (Thompson) (Deep-sea).
* 101. Merlucctus gayi (Guichenot) Pescada, merluza (C.S.)
102. Merluccius australis (Hutton) Pescada, merluza. (S.)
103. Macruronus magellanicus Loénnberg Merluza de cola. (S.)
104. Macruronus novae-zelandiae (Hector) Merluza de cola. (S.)
XLV CORYPHAENOIDIDAE Granaderos
105. Coryphaenoides holotrachys (Giinther) (Deep-sea).
106. Coryphaenoides ariommus Gilbert y
Thompson (Deep-sea).
107. Coryphaenoides ariommus (Giinther) (Deep-sea).
108. Celorhynchus fasciatus (Giinther) (Deep-sea).
109. Celorhynchus chilensis Gilbert y
Thompson (Deep-sea).
110. Celorhynchus patagoniae Gilbert y
Thompson (Deep-sea).
111. Macruroplus pudens (Gilbert y Thomp-
son) (Deep-sea).
XLVI MACRORHAMPHOSIDAE
112. Macrorhamphosus fernandezianus
(Delfin) (JF)
XLVII SYNGNATHIDAE
118. Syngnathus scicularis Jenyns Aguja de mar. (N.C.S.)
114. Syngnathus pelagicus Linnaeus Aguja aguja de mar. (S.)
115. Leptonotus blainvillianus (Eydoux
Gervais) Aguja de mar. (C.S.)
XLVIII CYPRINODONTIDAE
116. Orestias agassizi Valenciennes (N.Freshwater).
Ie
118.
iil
120.
121.
122.
123.
124,
125.
126.
127.
128.
129.
130.
131.
132.
133.
134.
135.
136.
137.
138.
139.
140.
141.
142.
143.
144,
145.
146.
147.
148.
149.
150.
151.
CHILEAN FISHES AND THEIR VERNACULAR NAMES
XLIX TRACHIPTERIDAE
Trachipterus altivelis Kner
(C.S.)
L TRACHICHTHYIDAE
Trachichthys fernandezianus Gimnther
LI MUGILIDAE
Mugil cephalus Linnaeus
Mugil curima Cuvier y Valenciennes
LII ATHERINIDAE
Notocheirus hubbsi Clark
Basilichyhys australis FEigenmann
Basilichyhys microlepidotus (Jenyns)
Basilichyhys gracilis (Steindachner)
Odontesthes mauleanum (Steindachner)
Odontesthes wiebricht Eigenmann
Odontesthes itatanum (Steindachner)
Odontesthes brevianalis (Giinther)
Odontesthes laticlavia (Valenciennes)
Odontesthes smittt (Lahille)
Odontesthes nigricans (Richardson)
Odontesthes regia (Humboldt)
LII SERRANIDAE
Percichthys trucha (Valenciennes)
Percichthys melanops Girard
Percilla gillissi Girard
Percila irwinit Eigenmann
Acanthistius pictus (Tschudi)
Gilbertia semicincta (Valenciennes)
Hemelutjanus macropthalmos Tschudi
Polyprion oxygeneios (Schneider)
Paralabrax humeralis (Valenciennes)
Paralabrax semifasciatus
Prionodes huascartt (Steindachner)
Diplectrum conceptione (Valenciennes)
Caprodon longimanus (Gtnther)
Hemanthias peruanus (Steindachner)
Callanthias platei Steindachner
(JF)
Liza. (N.C.S.JF)
271
Liza. (N.)
(C.)
Pejerrey. (Freshwater).
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
Pejerrey.
(Freshwater).
(JF)
(Freshwater).
(Freshwater).
(Freshwater).
(Freshwater).
(Freshwater).
(S.)
(S.)
(N.C.S.)
Trucha, perea trucha.
(Freshwater).
Trucha, perea trucha.
(Freshwater).
Carmelita. (Freshwater).
Carmelita. (Freshwater).
(N.C.)
Cabrilla listada. (JF)
Ojo de uva, papaniagua. (N.)
Baealao.
Cabrilla.
(Chile)
(S.JF)
(JF)
(Chile)
(JF)
LIV BRANCHIOSTEGIDAE
Prolatilus jugularis (Valenciennes)
Caulolatilus princeps (Jenyns)
Blanquillo.
(Chile)
LV POMATOMIDAE
Pomatomus saltatrix (Linnaeus)
(C.)
LVI RACHYCENTRIDAE
Rachycentrodon canadum (Linnaeus)
(JF)
(JF, SFA)
(N.C.S.JF)
(N.C.S.)
272
152.
153.
* 154,
salop.
156.
157.
158.
159.
* 160:
161.
162.
163.
164.
165.
166.
167.
168.
169.
170.
as
172.
Beviios
174.
175.
176.
177.
178.
UE
180.
181.
EIGHTH PACIFIC SCIENCE CONGRESS
LVII CARANGIDAE
Seriola mazatlana (Steindachner) (JF)
Seriola dorsalis (Gill) (N.)
Neptomenus crassus Starks Conjinoba. (N.)
Trachurus murphyi Nichols Jurel, furel. (N.C.S.JF)
Caranx georgianus Valenciennes Palometa, pampanito. (JE)
Parona signata (Jenyns) (S.)
Lichia albacora Guichenot Albacora. (C.S.)
Trachinotus paitensis Cuvier y Valen-
ciennes (C.)
LVIII LEPIDOTIDAE
Lepidotus chilensis (Guichenot) (C.)
LIX CORYPHAENIDAE
Coryphaena hippurus Linnaeus Dorado. (N.)
LX EMMELICHTHYIDAE
Emmelichthys cyanescens (Guichenot)(C.)
LXI SCIAENIDAE
Cynoscion analis (Jenyns) Allanque. (N.C.)
Sciaena gilberti Abbott Corvinilla. (N.C.S.)
Sciaena deliciosa (Tschudi) Corvinilla. (N.)
Sciaena fasciata (Tschudi) Corvinilla. (N.C.)
Sciaena reedi (Gtinther) (JF)
Sciaena imberbis (Giinther) (N.C.JF)
Micropogon furniert (Desmarest) Corvina. (N.C.JF)
Stellifer minor (Tschudi) Corvinilla. (N.C.)
Menticirrhus ophiocephalus (Jenyns) Pichiguen. (N.JF)
LXII POMADASYIDAE
Pomadasys bipunctstus Kner (N)
Isacia conceptionis (Cuvier) Cabinza. (C.N.)
Cilus monti Delfin Corvina. (N.C.S.)
Anisotremus scapularis (Tschudi) Sargo. (N.)
LXIII SCORPIDAE
Scorpis chilensis (Guichenot) Pampanito. (JF)
LXIV GIRELLIDAE
Girella albostriata Steindachner Jeringuilla. (JF)
Girella foliciana Clark (SF)
Doydimodon laevifrons (Tschudi) Baunco. (N.)
LXV HISTIOPTERIDAE
Pentaceros kneri Steindachner (S.)
LXVI OPLEGNATHIDAE
Oplegnathus insignis (Kner) Loro. (N.)
* 182.
183.
184.
185.
186.
187.
188.
~ alee
190.
il
192.
193.
194.
195.
196.
197.
198.
199.
200.
201.
S202:
208.
204.
205.
206.
207.
208.
209.
210.
211.
212.
CHILEAN FISHES AND THEIR VERNACULAR NAMES
273
LXVII APLODACTYLIDAE
Aplodactylus punctatus Valenciennes
Aplodactylus vermiculatus Valencien-
nes
Aplodactylus guttatus Valenciennes
Jerguilla. (C.N.)
Jerguilla. (C.)
Jerguilla. (JF)
LXVIII POMACENTRIDAE
Chromis crusma (Valenciennes) Castafieta, burrito, pampa-
nito, frailecillo. (N.C.S.)
Abudefduf saxatilis (Linnaeus) (N.)
Nexilosus latifrons (Tschudi) Castaneta, pampanito. (N.)
LXIX LABRIDAE
Pimelometopon maculatus (Perez) Peje perro, vieja colorada.
(N.C.S.)
Pimelometopon darwini (Jenyns) Peje perro, pejeperro. (N.)
Bodianus diplotaenia (Gill) (N.)
Pseudolabrus gayi (Valenciennes) (JF)
Graus nigra Philippi Vieja, vieja negra. (C.N.)
Malapterus reticulatus Valenciennes Biya. (JF)
LXX CHEILODACTYLIDAE
Cheilodactylus gayi (Kner) Breca. (S.JF)
Cheilodactylus variegatus (Valencien-
nes) Pintadita, pintadilla. (N.C.)
Cheilodactylus antoni (Valenciennes) Bilagai. (C.)
Cheilodactylus bicornis (Steindachner) (JF)
LXXI LATRIDAE
Mendosoma lineata Guichenot Trompetero, trompero. (C.)
Mendosoma caerulescens Guichenot Cabinza. (C.)
Mendosoma fernandezianum Guichenot Cabinza. (C.)
Latris hecateia Richardson (S.)
LXXII MUGILOIDIDAE
Mugziloides chilensis (Molina) Robalo, rollizo. (N.C.S.)
Parapercis chilensis Norman (S.)
LXXIII TRACHINIDAE
Trachinus cornutus Valenciennes (N.)
LXXIV BOVICTIDAE
Bovictus chilensis Regan Torito. (C.S.JF)
Cottoperca govio (Giinther) (S.)
LXXV NOTOTHENIDAE
Notothenia brevicauda Loénnberg (S.)
Notothenia canina Smitt (S.)
Notothenia cornucola Richardson (S.)
Notothenia elegans Giinther (S.)
Notothenia jordani Thompson (S.)
Notothenia longipes Steindachner (S.)
274
213.
214.
215.
216.
217.
218.
219.
220.
221.
222.
223.
224.
225.
226.
227.
228.
229.
230.
231.
232.
233.
234.
235.
236.
237.
238.
239.
240.
241.
242.
243.
244,
245.
EIGHTH PACIFIC SCIENCE CONGRESS
Notothenia macrocephala Giinther
Notothenia microlepidota Hutton
Notothenia sima Richardson
Notothenia squamiceps Peters
Notothenia tessellata Richardson
Notothenia wiltoni Regan
Dissostichus eleginoides Smitt
Eleginops maclovinus (Valenciennes)
Harpagifer bispinis (Schneider)
LXXVI BLENNIDAE
Salarias chilensis Clark
Salarias viridis Valenciennes
Salarias rubro-punctatus Valenciennes
Salarias petersoni (Fowler)
Salarias variolatus Valenciennes
Scartichthys gigas (Steindachner)
Scartichthys concolor (Philippi)
Scartichthys modestus (Philippi)
Scartichthys eques (Steindachner)
LXXVII CLINIDAE
(Jenyns)
(Valencien-
Auchenionchus crinitus
Auchenionchus variolonis
nes) ~
Calliclinus geni-guttatus
nes)
(Valencien-
(Philippi)
(Valenciennes)
Valenciennes
(Steindachner)
Myxodes foncki
Myxodes viridis
Myxodes cristatus
Lepisoma philippii
Labrisomus microcirrhis (Valencien-
nes)
(Philippi)
(Fowler)
Labrisomus niger
Labrisomus conventryi
Labrisomus fernandezianus (Guiche-
not)
Labrisomus guttulatus (Valenciennes)
(Valenciennes)
(Jenyns)
Petroscirtes biocellatus
Petroscirtes fasciatus
(C.S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
Robalo, robalito, robalo de
piedra. (C.S.)
(S.)
(C.)
Borracho, torito.
Torito. (C.JF)
Torito. (N.)
(JF)
Torito, borracho, suefo.
(N.C.)
Torito.
Torito.
Torito.
(N.C.)
(C.)
(C.)
(N.C.S.)
Tramboyo. (N.)
Tramboyo. (N.C.S.)
Vieja, tomoyo, tramboyo.
(C.S.)
Doncella. (S.)
Doncella. (N.C.S.)
Doncella. (C.)
Trombollo, tomoyo, vieja.
(N.)
Trombollo, tomoyo, vieja.
(C.)
(Chile)
Trombollo, tomoyo, vieja.
(C.)
Tromobollo, tomoyo, vieja.
(JF)
Trombollo, tomoyo, vieja.
(C.S.)
Torito.
Torito.
(C.)
(C.S.)
LXXVIII CHAENNICHTHYIDAE
Champsocephalus esox (Giinther)
(S.)
246.
247.
248.
249.
250.
251.
252.
253.
254.
250.
256.
257.
258.
259.
260.
261.
* 262.
* 263.
* 264.
265.
* 266.
* 267.
* 268.
* 269.
* 270.
PMN
272.
1 Palle
CHILEAN FISHES AND THEIR VERNACULAR NAMES
LXXIX ZOARCIDAE
Ophthalmolycus macrops (Gunther)
Tlwocoetes finbriatus Jenyns
Iluocoetes elongatus (Smitt)
Austrolycus depressiceps (Regan)
Austrolycus laticinctus (Berg)
Phucocoetes latitans Jenyns
Crossostomus chilensis (Regan)
Crossostomus fasciatus (L6énnberg)
Platea insignis Steindachner
Maynea puncta (Jenyns)
Maynea patagonica Cunningham
Melanostigma gelatinosum Gtinther
275
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
(S.)
LXXX LYCODAPODIDAE
Lycodapus australis Norman
Gymnelis pictus (Giimnther)
LXXXI BROTULIDAE
Cataetryx messiert (Giinther)
LXXXII OPHIDITIDAE
(Schneider)
(Guichenot)
Genypterus blacodes
Genypterus chilensis
Genypterus maculatus (Tschudi)
LXXXIII GEMPYLIDAE
Thyrsites atun (Euphrasen)
Thyrsitops lepidopodes (Cuvier)
LXXXIV SCOMBRIDAE
Pneumatophorus peruanus Jordan y
Hubbe
LXXXV THUNNIDAE
Thunnus thynnus saliens Jordan y
Evermann
Germo alalunga (Bonnaterre)
Neothunnus macropterus (Schlegel)
Katsuwonus pelamis (Linnaeus)
LXXXVI CYBIIDAE
Sarda chilensis (Cuvier)
(S.)
(S.)
(S.)
Abadejo. (S.)
Congrio colorado, colorao.
(N.C.S8.)
Congrio negro, mono.
(N.C.S.)
(C.S.)
(S.)
Sierra.
Sierra.
Caballa. (N.C.)
Cimarron. (C.)
Attn, atin de aleta larga.
(N.C.S.)
Attn, atin de aleta amarilla.
(N.)
Cachurreta. (N.)
Bonito o mono. (N.C.S.)
LXXXVII ISTIOPHORIDAE
Makaira audax (Philippi)
LXXXVIII XIPHIIDAE
Xiphias gladius Linnaeus
Pez aguja. (N.C.S.)
Albacore. (N.C.S.)
276
* 274.
275.
276.
277.
278.
279.
280.
281.
282.
283.
284.
285.
286.
287.
288.
289.
290.
291.
292.
* 293.
294.
Sebastodes oculatus
EIGHTH PACIFIC SCIENCE CONGRESS
LXXXIX STROMATEIDAE
Stromateus maculatus Cuvier y Va-
lenciennes
XC CENTROLOPHIDAE
Palinurichthys caeruleus (Guichenot)
Leirus peruanus (Steindachner)
XCI NOMEIDAE
Seriolella porosa Guichenot
Seriolella violacea Guichenot
eet
XCII GOBIIDAE
Gobius chiloensis Guichenot
Gobiosoma ophiocephalum (Jenyns)
Pampanito. (JF)
Pampanito. (JF)
(N.)
Cojinoba, casinova, hachita.
(N.C.S.)
Cojinoba, casinova, hachita.
(C.)
(S.)
(S.JF)
XCIII SCORPAENIDAE
(Cuvier)
Sebastodes prognathus Tortonese
Sebastodes darwinit (Cramer)
Sebastodes chilensis Steindachner
Helicolenus lengericht Norman
Scorpaena thomsoni Ginther
Scorpaena fernandeziana Steindachner
Scorpaena histrio Jenyns
XCIV TRIGLIDAE
Cabrilla, cabrilla espamola.
(N.C.S.)
(C.)
Cabrilla. (N.C.S.)
Vieja colorada, cabrilla.
(C.S.)
(JF.)
Peje diablo. (JF)
Peje diablo. (JF)
jPeje diablo. (JF)
Trigla guttata Philippi (JF)
Cheilidonichthys pictus (Ginther) (JF)
XCV CONGRIOPODIDAE
Congriopus peruvianus (Cuvier y Va-
lenciennes)
Agriopus hispidus (Jenyns)
XCVI COTTIDAE
Peje chancho, chanchito.
(N.C.S.)
Chanchito, peje chancho. (S.)
(Including NORMANICHTHYIDAE)
Normanichthys crokert Clark
(C.S.)
Mote, cochinilla.
XCVII PSYCHROLUTIDAE
(=NEOPHRYNICHTHYIDAE)
Neophrynichthys marmoratus Gill (S.)
XCVIII AGONIDAE
. Agonopsis chiloensis (Jenyns) (C.S.)
308.
309.
310.
311.
312.
313.
* 314.
CHILEAN FISHES AND THEIR VERNACULAR NAMES 277
XCIX CICLOPTERIDAE
(Including LIPARIDAE and LIPAROPIDAE)
. Cyclopterichthys amissus Vaillant (S.)
. Careproctus falklandica (Loénnberg) (S.)
. Careproctus pallidus (Vaillart) (S.)
C SCOPHTHAIMIDAE
. Thysanopsetta nareri Giinther
Lenguado. (S.)
. Hippoglossina macrops Steindachner
Lenguado. (C.S.)
. Hippoglossina mystacium Ginsburg
Lenguado. (S.)
. Paralichthys adspersus (Steindachner)
Lenguado. (N.C.JF)
. Paralichthys fernandezianus Stein-
dachner Lenguado. (JF)
. Paralichthys patagonicus Jordan
Lenguado. (S.)
. Paralichthys hilgendorfi Steindachner
Lenguado. (JF)
. Paralichthys microps Giinther)
Lenguado. (N.C.S.)
. Paralichthys schmitti Ginsburg
Lenguado. (JF)
Paralichthys coeruleostica Steindach-
ner Lenguado. (JF)
CI ECHENEIDAE
Remora remora (Linnaeus) Piloto, remora. (N.C.S.)
CII DIODONTIDAE
Diodon hystrix (Linnaeus) Erizo. (P.)
CIII MOLIDAE
Mola mola (Linnaeus) Peje luna, peje sol. (C.S.)
CIV GOBIESOCIDAE
Sicyases sanguineus Miller y Troschel Peje sapo. (C.N.JF.)
Sicyogaster marmoratus (Jenyns) Peje sapo. (S.)
CV BATRACHOIDIDAE
Aphos porosus (Valenciennes) Peje bagre. (N.C.S.)
For the preparation of this list of Chilean fishes, different papers
were consulted, Guichenot’s in Gay, Philippi, Perez Canto, Delfin and
others; but particularly we have been guided by Fowler’s catalogue,
published in the years 1941 to 1943 in the “Revista Chilena de Historia
Natural.” The families have been arranged according to Berg’s classi-
fication (1940). The fresh water species have been checked with Eigen-
278 EIGHTH PACIFIC SCIENCE CONGRESS
mann’s study published by the U.S. National Academy of Sciences (Vol.
XXII, Report I), modifying the generic denominaticns of the Atheri-
nidae according to our own judgment. We have kept in mind for
the north of Chile the similar fish fauna of Peru, as described in Hil-
debrand’s paper (U.S. Nat. Mus. Bull. 189, 1946), and for the Southern
part of the country, Norman’s paper in the Discovery Reports (vol.
XVI, 1937).
During our assignment in Chile (15 February to 15 August 1953),
we continued the work started by Dr. Erick M. Poulsen, FAO expert,
who concentrated on the biology cf bottom fishes, especially the hake
(two species of Merluccius). We have paid special attention to pelagic
species, of seasonal abundance in the fishing grounds, including repre-
sentatives of the Thunnidae, Cybiidae, Xiphiidae, Engraulidae and Clu-
peidae.
At the time of our survey, all the Thunnidae approached the Chi-
lean coast in search of food, with their gonads inactive. Neothunnus
macropterus, which appears off the coasts of the provinces of Tarapaca
and Antofagasta comes in through oceanic waters, feeding then prin-
cipally on pelagic crustaceans, and soon invades the green coastal waters
in search of Engraulis; this fishery is the basis of a coming industry,
and in years of abundance a catch of about 1,000 tons is obtained, al-
though in poor years the catch diminishes to only 50 tons a year. Ger-
mo alalunga, called Germo germo by some authors, is the tuna of cen-
tral Chile, which in small groups can reach Talcahuano and is also
frequent along the northern zone. It may be missing some years, but
even with the present primitive fishing gear, up to 500 tons a year can
be caught. Albacore is used for fresh fish consumption, either directly
or frozen, or for canning.
We had the opportunity to examine some specimens of what we
have called Thunnus thynnus saliens in view of the small differences
observed compared with Atlantic tuna. Its scarcity is due principally to
the gear employed, which is the same used to catch albacore, and which
do not stand the strain of very big specimens.
The only Cybiidae of Chile, Sarda chilensis, with a catch of nearly
5,000 tons, approaches the north coast to spawn, generally in cold green
water; in July specimens with very developed gonads are found.
The swordfish, inhabitant of warm, blue, oceanic waters, is of great
economic importance, as up to 2,000 tons per year can be caught off
the northern coast. It appears also at times in the Valparaiso area
reaching as far south as Talcahuano.
We have only been able to find one Engraulidae in Chilean waters
(Engraulis rengens), of which we studied more than 1,000 specimens.
CHILEAN FISHES AND THEIR VERNACULAR NAMES 279
This anchovy is of great interest, not only from the industrial point of
view, but also because it is the primary food supply of many species
of fish. Thunnidae and Cybiidae in the northern coast feed on an-
chovy. Its schools are prayed upon by other species of larger size and
also by the guano birds (Pelecanus occidentalis thagus, sula variegata,
Phalacrocorax bougainvilli) and marine mammals (Otaria byronia). It
is also used for bait by the fishermen.
Among the Clupeids the most important is the sardine, which we
have called Sardinops sagax sagax, to separate it as a mere subspecies
of the Sardinops sagax caerulea of California. The Chilean sardine
is abundant in the northern coast, principally in the Antofagasta zone.
EDIBLE SHELLFISH OF THE CHILEAN COAST
By FRANCISCO RIVEROS-ZUNIGA
Estacion de Biologica Marina de la Universidad de Chile
Montemar, Chile
In 20 years shellfish production of Chile has risen from 5,180 tons
in 1931 to 19,931 tons in 1951, the largest increases being recorded in
1940 and 1946. The zones of Puerto Montt, Talcahuano, Valparaiso,
and Antofagasta are the most important producing areas for edible
crustaceans and molluscs. Puerto Montt produces almost 80% of all
shellfish consumed in the country; 46°% of its local production is used
for canning and in this form distributed all over the country.
However, as exemplified by the CHORO (Choromytilus chorus
Molina, 1782), the production of some species has steadily declined. In
fact, its catch decreased during the period 1930-1943 from 3,237 to 1,651
tons. ‘This calls for the immediate adoption of conservation measures.
On the other hand, from 1945 to 1951, the total production of OYSTERS
(Ostrea chilensis Philippi, 1845) has mounted from 260 to 598 tons or
more than double. This increase is due to enforced conservation prac-
tices and to annual restocking of depleted beds.
The most sought after species of shellfish, from the industrial point
of view are: LANGOSTINOS (Plated lobsters), ALMEJAS (Clams),
CALAMARES (Squids), CENTOLLAS (King crabs), CHOLGAS (Mus-
sels), CHORITOS (Horse-mussels), ERIZOS (Sea urchins), TACAS
(Hard clams), PICOS (Giant acorn-shells), PIURES (Edible sea-squirts),
APANCORAS and CANGREJOS (Crabs), on which information will be
given later on.
In 1951 the amount of shellfish used for canning was 7,244,061 Kg.
with a net yield, on an edible basis, of 1,223,921 Kg. The consumption
of fresh shellfish during the same year reached a total of 12,684,405 Kg.
with a net yield of 1,569,100 Kg.
ECHINODERMATA
Loxechinus albus (Molina, 1782). ERIZO COLORADO o ERIZO
COMESTIBLE (Red or Edible Sea Urchin). Among the echinoderms of
Chile the only one of commercial value and preferably consumed fresh.
The gonads, commonly called lenguas de erizo (sea urchin tongues),
are canned in oil, mostly in small plants located at the Island of Cal-
buco. In addition, along the coast from Callao, Peru, to the Magel-
280
EDIBLE SHELLFISH OF THE CHILEAN COAST 281
lanic province, it is consumed fresh in great quantities wherever abun-
dant.
CRUSTACEA
Lithodes antarcticus (Hombron et Jacquinot, 1853). CENTOLLA
(King crab). A crustacean much sought after for processing due to the
quality and good taste of its flesh. The catch during 1950 and 1951
has decreased considerably, being of 61 and 55 tons respectively, while
in years of abundance (1946) it amounted to 126 tons. Its area of dis-
tribution on the Chilean coast extends from Puerto Montt to the Strait
of Magellan. It has also been found in the deep waters of the coast of
Buenos Aires, Argentina. The fishing grounds in Chile are in the region
of Calbuco, Quellén, Aysen, southern canals, and the Strait of Magellan;
in the Republic of Argentina it is caught in Ushuaia, in the Beagle
canal, but production in that country is lower than in Chile (43 tons
in 1938), (Carcelles, 1946). It is fished in shallow waters during the
season when it approaches the beaches. It is sold canned in oil, but its
{fresh consumption is also considerable, though not recorded statistically
(Schwabe, 1939 and 1941).
Jasus lalendei frontalis (Milne Edwards, 1837). LANGOSTA DE
JUAN FERNANDEZ (Spiny lobster) found in the Archipelago of Juan
Fernandez and the Desventuradas Island (San Ambrosio and San Félix),
(Holthuis, 1951). Because of its economic importance and the great
domestic and foreign demand from Argentina, where it is also sent by
air, unsuccessful attempts have been made to acclimatize this species in
the Chilean mainland coast (Albert, 1898). Production registered be-
tween 1945 and 1951 shows the lowest catch in 1946 (56 tons) and the
highest in 1948 (106 tons).
Balanus (Megabalanus) psittacus (Molina, 1782). PICO DE MAR
or PICOROCO (Giant acorn-shell) in the region of Chiloé. Its wide
area of distribution extends from Pascamayo (Peru!) to the Strait of
Magellan. Principal processing centres are Calbuco and Puerto Montt.
The most important crustacean for industrial purposes, canned “au
naturel” and in oil, and also in great demand for fresh consumption.
Its catch amounted in 1945 to 307 tons and increased in 1951 to 407
tons.
LANGOSTINOS (Plated lobsters). This name is given in Chile to
three species: Munida gregaria Leach, Plewroncodes monodon Milne
Edwards, and Cervimunida johni Porter, 1903. They are canned in
jelly, mostly in the Valparaiso zone. In 1951, 19 tons were processed.
APANCORAS (Crabs). Statistics on shellfish production compiled
by the Chilean Department of Fish and Game (Hernandez, 1953) in-
clude under this item all species of JAIBAS (Crabs) consumed in Chile,
282 EIGHTH PACIFIC SCIENCE CONGRESS
of which the most utilized are: Cancer polyodon Poeppig, 1836 and
C. plebejus Poeppig, 1836 (JAIBA PELUDA); Homalaspis plana Milne
Edwards, 1834 (JAIBA MORA or MORADA); Ovalipes punctatus De
Haan, 1833 and Taliepus dentatus Milne Edwards, 1834 (PANCHOTE).
The aggregate catch was over 300 tons between 1945 and 1949, but
declined in 1949, to increase in 1951 to 623 tons.
CAMARON DE MAR (Prawn), Rhynchocinetes typus Milne Ed-
wards, 1837. Of wide distribution; found in Chile, Peru, New Zealand,
and Indian Ocean. In Chile its production has decreased from 83 in
1947 to 16 tons in 1951, Valparaiso being one of the most important
producing centres.
‘TUNICATA
PIURE or PIVRE (Sea-squirt), Pyura chilensis Molina, 1782 (Van
Name, 1945) of wide distribution, from the Peruvian port of Mollendo
(17°S) in the North to Chiloé Is. (about 42°S). It lives in shallow
waters and is caught mostly for fresh consumption. Some factories in
Calbuco can it “au naturel.’ It is an irregular oval shaped tunicate
growing in very close groups, each individual independent with its own
cuticular test. Its test and internal organs are consumed fresh or
smoked; industrial utilization is negligible. In 1948, 235 tons were
caught, but production has considerably diminished and in 1951 was
only 91 tons.
MOoOLLUSCA
CEPHALOPODA
CALAMAR (Squid), Loligo gahi D’Orbigny, 1835. Small cepha-
lopoda about 10 cm. long consumed canned in oil. Although its area
of distribution is extensive, including the biogeographical Peruvian
and Patagonian provinces of South America, it is only processed in Cal-
buco with a net production of 1,111 Kg. in 1951. It is also used as
fishing bait. ;
PULPO (Octopus), Polypus fontaineanus D’Orbigny, 1835. In-
habitant of the Chilean and Peruvian coasts; of a vivid red colour with
granulated body surface. The maximum length observed is about 25
cms. Its arms are eaten, but it is not processed and is captured in small
quantities.
JIBIA (Cuttlefish), Dosidicus gigas D'Orbigny, 1835. Big nocturnal
cephalopoda usually beached in great quantities at Ritoque, Refiaca,
Constitucién and Talcahuano; utilized as fishing bait for cusk eel
(Genypterus sp.).
EDIBLE SHELLFISH OF THE CHILEAN COAST 283
GASTROPODA
LOCO, Concholepas concholepas Brug. 1789. Gastropoda of eco-
nomic importance attaining great size; 33 tons were utilized in 1951
and canned in three ways: in oil, special brand, and “au naturel.” It
is hand picked in the intertidal zone or by divers with or without div-
ing equipment. The principal fishing centres are Los Vilos, Quintero,
Valparaiso and Puerto Montt. The mollusc’s powerful foot is consumed
tenderized by beating together with salt or with sawdust before cook-
ing. It is processed in the region of Calbuco and Puerto Montt.
- Other gastropods of popular demand are:
CARACOL GRANDE DE ESPUELA (Chorus), Chorus giganteus
Less., 1829. Found originally in Concepcion; its area of distribution
extends up to the bay of Valparaiso (Riveros-Zuniga, 1950) ; caught in
traps baited with fish or crustacean wastes; eaten cooked; taste resem-
bling that of Concholepas concholepas.
CARACOLES (Top-shells). Under this name are consumed some
edible species of the genera Tegula, such as 7. atre Less., 1830, the
MELONHUE of the Chiloé zone; T. tridentata Potiez et Michaud, 1838;
T. quadricostata Gray, 1838; Acanthina calcar Martyn (Unicorn-shell),
1784 and Turbo (Prisogaster) niger (Turbine-shell) Wood, 1828,
known as LILIHUEN. Not processed, but sought after by the fishermen
to be eaten cooked.
Fissurella (Keyhole limpets). Abundant gastropods whose tasteful
foot is frequently consumed fresh. Also called CHAPAS or CHAPES.
‘The most used species are F. maxima Sow., 1834; F. picta Lamk, 1822;
F. crassa Lamk, 1822; F. limbata Sow., 1834; F. latemarginata Sow.,
1834; (Riveros-Zuniga, 1951). Area of distribution generally very ex-
tensive. Abundant in the intertidal zone on the bare rocks or on those
covered by algae.
Patella, Nacella, Scurria, Siphonaria (Limpets) are genera whose
species are sought as food and called LAPAS, a name which is applied
in general to mollusks with conical shell which adhere strongly to the
rocks or other supports. Some species utilized are Patella magellanica
Gmelin, 1791; Nacella clypeater Less., 1830; Scurria scurra Less., 1830;
and Siphonaria (Liriola) lessoni Blainville, 1824.
Thais chocolata Duclos, 1832, (Thais) is found from Paita in Peru,
where it is called CARACOL, to Valparaiso. In Coquimbo and vicinity
it is known as LOCATE or LOCA because of its resemblance in taste to
the Concholepas concholepas. Fished by divers and very well liked.
PIQUILHUE (Volutes) Adelomelon magellanicus Lamk, 1811 and
A. ancilla Sow., 1786, are the species consumed in the region of Chiloé.
284 EIGHTH PACIFIC SCIENCE CONGRESS
AMPHINEURA
Chiton and Tonicia (Chitons) are genera of Polyplacophora with
some species found in the market. In a number of Chilean ports they
are sold under the name of COGOTES, but they find little acceptance.
PELECYPODA
From the industrial point of view, the following families are of
importance, (by order of value): Mytilidae, Ostreidae, Mesodesmatidae,
Veneridae and Pectenidae.
Among the Mytzlidae the total volume of production in 1945 was
9,950 tons and 12,289 in 1951, the highest production being in 1946
with 15,082 tons. The catch of the most valuable species has diminished
a great deal due to uncontrolled and extensive exploitation, leading to
the extraction of very young specimens, to the evident danger of the
conservation of the species. The fishing methods, which literally collect
every specimen from the beds, have had a depleting effect shown in the
disappearance of the beds nearest to the factories; therefore it has been
necessary to search for them in more distant places.
To the new genus Choromytilus (Soot-Ryen, 1952) belongs C.
chorus (Molina, 1782) CHORO (Giant mussel) with area of distribu-
tion from Pascamayo (Peru) to Orange Bay (Chile). Its uncontrolled
exploitation continued for decades has caused depletion and there is
urgent need of protecting the species. It is the biggest of the marine
choros and is greatly esteemed from the nutritive point of view. It
adheres to its supports through a strong byssus and has a big oval ob-
long shell, bluish in colour, covered by a blackish periostracum.
Mytilus ater Molina, 1782, Aulacomya magellanica Chemnitz, 1819
(Carcelles, 1942), and M. chilensis Hupé, 1854, are commonly called -
CHOLGAS (Mussels). ‘The first has a smooth surface and is found from
Manta (Ecuador) to Talcahuano; the second abundant in Magallanes
but is found north up to Valparaiso, and the last along an extended
area from Callao (Pert) to Tierra del Fuego, Falkland Is., and the
coast off Buenos Aires. The total production of CHOLGAS is around
4,000 to 7,000 tons. They are usually consumed fresh or smoked. In
1951 canned production amounted to 2,900 tons, “au naturel,” special
brand, and in oil. The Puerto Montt zone (Calbuco, Puerto Aguirre,
Quellon, Aulén, San Rafael) industrializes the greatest quota of cholgas.
M. chilensis, called CHILEAN or SOUTHERN MEJILLON, is caught in
Tierra del Fuego, Patagonia and Strait of Magellan. Aulacomya ma-
gellanica Chemnitz, is the GRAN MEJILLON OF MAGALLANES (Ma-
gellanic large mussel) or CHORO or MEJILLON RAYADO.
EDIBLE SHELLFISH OF THE CHILEAN COAST 285
Modiolus dayctiliformis Hupé, is characterized by its oblong shape,
smoothed at the umbo and by the brownish green periostracum; the
inside of the shell is nacreous tinged with violet. The CHORITO or
QUILMAHUE (Horse-mussel) is found from Antofagasta to the Chiloé
zone, but only consumed by fishermen.
Brachydontes purpuratus Lamk, 1797 is the CHORITO MAICO
(Purple horse-mussel) found along all the Chilean coast, Tierra del
Fuego, Falkland Is., and Argentine coast up to Golfo Nuevo, also called
MEJILLON DEL SUR or MEJILLON PURPURA. It is fished in all its
area, but not for industrial purposes.
Ostrea chilensis Philippi, 1845, the OSTRA CHILENA (Oyster)
found in an extended area from the coast of California to the zone
of Chiloé. It is the most demanded mollusk. Its exploitation has in-
creased since 1945 from 260 tons to 598 tons in 1951, Ancud being the
zone of greatest production. This production comes principally from
artificially stocked beds and has been helped by timely restrictions.
Pecten (Plagioctenum) purpuratus Lamk, 1819, OSTION is the
Chilean scallop most in demand, with orbicular, convex shell, with 26
ribs and pinkish white colour. The adductor muscle has a delicious
flavour and is preferably consumed fresh. In 1945, 65 tons, in 1950,
387 tons, and in 1951 only 262 tons were extracted.
Chlamys patagonicus King, 1831, OSTION MAGALLANICO (Ma-
gellanic scallop). Very common in the coasts of the Strait of Magellan
and in the fjords up to Puerto Montt, but not of great economic value.
Protothaca thaca Molina, 1782, TACA (Hard clam) is found from
Ancon (Pert) to the Chonos Archipelago and is in demand because
of its excellent taste to be consumed baked on embers or in soups or
“curantos’” (primitive preparation of shellfish and algae, cooked in
ground holes with hot stones). Production in 1950 and 1951 has
amounted to 901 and 913 tons respectively.
Mesodesma donacium Lamk, 1818, MACHA (Soft shell clam), is
found from Chiloé to the Sechura Bay, in Peru. Maximum production
amounted to 668 tons in 1951. Its white shell is covered by a straw
yellow periostracum and of its ends the shortest is subtruncate and the
widest, compressed and channelled. Obtained in great quantities in
Las Ventanas of Quintero, Iloca, etc.
Tagelus (Mesopleura) dombeyi Lamk, 1818, is one of the NAVA-
JAS DE MAR (Razor-clams), found from Tumbes, Peru, to the Chiloé
Is. Hinged with two inconspicuous cardinal teeth; consumed by the
coastal people and frequently found in southern markets where its local
name is QUIVI.
286 EIGHTH PACIFIC SCIENCE CONGRESS
Solen gaudichaudi Chemn, 1843, and Ensis macha Molina, 1782,
are called NAVAJUELAS DE MAR (Razor-shells).. The first is found
in a small area, from Valparaiso to Coquimbo, and the second, from
Valparaiso to Magallanes up to the Atlantic coast, reaching the Gulf
of San Matias (Carcelles, 1950). Both are sand species found at great
depths and collected at low tide.
Pholas (Thovana) chilensis Molina, 1782, commonly called COMES
(Piddock) is found from the Gulf of Panama to the Chiloé Is. Con-
sidered one of the best shellfish and known by its two anterior plates
with anterior-central nuclei, a small and transversial middle plate and
a long and narrow posterior plate. No lines in the third posterior of
the shell.
Mulinia bicolor Gray, 1837; M. edulis King, 1831, and M. byronen-
sis Gray, 1838, species which because of their resemblance to the TACAS
(Hard clams) are called TAQUILLAS (Small hard clams). ‘Their areas
of distribution are extensive: M. edulis is found from Callao to the
Strait of Magellan, M. byronensis from Salaverry (Peru) to the Strait
of Magellan, M. bicolor from Copiapo to Valparaiso. (Some authors
consider M. bicolor Gray synonymous with M. edulis). They are
frequently found in the markets of a number of sea ports in Chile.
REFERENCES
ALBERT, F. 1898. La Langosta de Juan Fernandez y la Posibilidad de su
Propagacién en la Costa Chilena. Rev. Chilena Hist. Nat., Ano II,
No. 1, Pp. 5-11. Valparaiso, Chile.
CARCELLES, A. 1942. Nota sobre el Mejillon Aulacomya magellanica Chem-
nitz. Physis, Vol. XIX, Pp. 180-190, Buenos, Aires, Argentina.
1946. Mariscos de las Costas Argentinas. Argentina Austral.,
Afio XVIII, Nos. 186-187, Pp. 1-20. Buenos Aires, Argentina.
HERNANDEZ, M. 1953. Informacioénes Estadisticas sobre Pesca. 57 Pp. Di-
reccién de Pesca y Caza. Valparaiso, Chile. |
HoLtTuHius, L. B. 1952. The Crustacean Decapoda Macrura of Chile. With
Spanish Abstract. Report Lund Univ. Chiie Hap. 1948-1949. Vol. 5,
110 Pp. Lunds Univ. Handl., N. F. Bd. 62, No. 10. Lund.
RiveRos-ZUNIGA, F. 1950. El Area de Distribucién de Chorus giganteus Less.,
1829. fev. Biol. Mar. Univ. Chile. Vol. III, Nos. 1-2, Pp. 157-161. Val-
paraiso, Chile.
SCHWABE, G. H. 1939. Uber die Mariscofischerei von Siidchile. Monatsh. fo
Fischerei, 7 Jg. N. F. Pp. 129-184. Hamburg, Germany.
1941. Aus dem siidchilenischen Kiistengebiet, XIII Uber Mariscos
und Mariscofischerei. Zeitschr. f. Fischerei. Vol. XXXIX, No. 8, Pp.
313-347. Frankfurt a.d. Oder.
Soot-RYEN, T. 1952. Choromytilus, a new genus in the Mytilidae. Rev. Soe.
Malacol. Carlos de la Torre, Vol. VIII, No. 3, Pp. 121-122. Havana, Cuba.
VAN NAME, W. G. 1945. The North and South American Ascidians. Bull.
Amer, Mus. Nat. Hist. Vol. 84, Pp. VIII + 476. New York, U.S.A.
NOTES ON THE COMMERCIALLY IMPORTANT
IM(Sla0as) Ove Clsvouss
By PARMENIO A. YANEZ
University of Chile Marine Biological Station
Montemar, Chile
The fish fauna of the coast of Chile, which extends from the border
of Peru (18°22’S) to Cape Horn (56°S), is constituted of coastal
species typical of the Chilean district, generally understood to be the
region between the latitudes of Valdivia (39°45’S) and Tocopilla
(22°41’S). Among these species are also found northern and southern
fishes from the Peruvian and Magellanic districts. Besides these species,
other pelagic ones are also found which migrate to the south through
the outer waters of the Coastal Current of Peru following, during their
transgresses and regresses, the tropical and subtropical oceanic waters.
The transgression of these waters, at a temperature and salinity of
about 15° and 35%, respectively, starts approximately in October,
reaches its maximum in February and its minimum in August, when
they move away from the coast, between Yocopilla and the province
of Cautin, a short distance north of Valdivia.
At the time of the regression of the warm waters, the cold waters,
with temperatures around 12°C, which during the summer do not sur-
pass the latitude of the peninsula of Taitao (46°30’S), extend towards
the north on a narrow coastal strip reaching as far as 32°S, a little
north of the site of the Marine Biological Station of Montemar (Esta-
cidn de Biologia Marina de Montemar), (32°51’24”S), located in the
Bay of Valparaiso.
The analysis of the observations made in the Marine Biological
Station since 1947, shows that the surface temperature of the sea water
fluctuated in February between 14° and 16°C; in August between
11° and 12°C, and in October, between 12° and 13°C. Occasionally
there has been a maximum of 18°C in February and a minimum of
around 9°C in August.
Thanks to the indicated facts, the Marine Biological Station is
located in the most favourable point of the Chilean coast regarding
ichthyological observations. The majority of the species character-
istic of the Magellanic and Peruvian districts reach the latitude of
the Station in question. Of the 50 species of commercial importance
considered below, only 7 were not caught in the neighbourhood of
287
288 EIGHTH PACIFIC SCIENCE CONGRESS
the Station, which is a small number compared with the 16 species
missing in the waters of Talcahuano (36°44’S), and 12 in the waters
of Antofagasta (23°38’S).
The annual changes of temperature of the surface waters on the
coast of Chile, besides determining the characteristics of the fish fauna
and the migrations of many of the species of fish, also establish a typical
annual cycle of plankton. Two distinct periods are found in the abund-
ance of plankton; the rich Spring period, which extends until the be-
ginning of Summer, and the poor Autumn period until the commence-
ment of Winter. In July and August there are also two short periods
of abundance and scarcity respectively (P. Yanez—Informacion preli-
minar sobre el ciclo anual de plancton superficial en la Bahia de Val-
paraiso (“Preliminary notes on the annual cycle of the surface plankton
of the Bay of Valparaiso’), Rev. Biol. Mar. I, 1, pp. 57-59).
Around one fifth of the 260 coastal and pelagic species (Selachit
and Teleostomz), listed for the Chilean coast up to date (Henry W.
Fowler—Fishes of Chile. Rev. Chilena de Hist. Nat. Santiago, Chile.
1943), are used as food by the inhabitants of the country. However,
not more than twenty, in view of the volume of the catch and industrial
value, are of real commercial importance.
A list of the species of fish of commercial value follows.
It is arranged systematically. Between brackets, following the sci-
entific name, is given the common denomination of the species mostly
utilized in the country, followed by the annual catch in tons, taken from
Moises. Hernandez Ponce—Informacidones estadisticas sobre la Pesca
(Statistical Information on the Fisheries) Valparaiso, Chile. 1953.
CLASS PISCES
SUB-CLASS ELASMOBRANCHII
ORDER SQUALIFORMS
Family Squalidae
1.—Squalus fernandinus Mol., 1782. Small size species found in
the water off the island of Juan Fernandez and in the continental coast
of Chile, from Valparaiso southwards. It has been extensively fished
until recently because of its liver, which is very rich in vitamin oil.
ORDER LAMNIFORMS
Family Carcharidae
2.—Mustelus mento (Cope, 1877) (TOLLO; 800 tons) Species of
medium size. Found from the Gulf of Arauco to Peru; mainly caught
between Caldera and Coquimbo. It has excellent flesh, which is con-
sumed fresh, dry, salted or smoked.
COMMERCIALLY IMPORTANT FISHES OF CHILE 289
ORDER CHIMAERIFORMS
Family Callorhynchidae
3.—Callorhynchus callorhynchus (L.) (PEJEGALLO; 300 tons).
Found along the whole coast. Its flesh is very much appreciated salted
or smoked.
SUB-CLASS TELEOSTOMI
ORDER CLUPEIFORMS
Sub-order CLUPEOIDEI
Family Clupeidae
4.—Ethmidium maculatum (Val., 1847) (MACHUELO; 800 tons).
It is the largest Chilean clupeid (length 35 cms.); it is caught from
the Gulf of Arauco northwards and it is consumed smoked or canned.
5.—Clupea fuegensis (Jen., 1842), (sardina comun)
6.—Sardinops sagax (Jen., 1842), (cardina espanola)
7.—Engraulis ringens (Jen., 1842), (anchoa)
The first species is found from Valparaiso southwards, and the
others, from the Gulf of Arauco northwards. ‘Their catch amounts to
8000 tons annually, and they are mostly canned; however, they are also
used for the manufacture of fish meal.
ORDER GADIFORMS
Family Gadidae
8.—Merluccius gayi (Guich., 1848), (PESCADA; 40,000 tons). Is
the most important species for human consumption. Inhabits the waters
from Caldera southwards; however, it is mainly caught between Valpa-
raiso and Talcahuano for fresh fish consumption and manufacture of
fish meal.
ORDER PLEURONECTIFORMS
Family Bathidae
9.—Paralichthys microps (Gthr., 1881).
10.—P. adspersus (Steind., 1867).
11.—Hippoglossina macrops (Steind., 1876).
These species are commonly known by the name of LENGUADO;
their meat is of good quality and is consumed fresh; however, their catch
is only about 400 tons yearly.
ORDER PERCIFORMS
Sub-order PERCOIDEI
Family Malacanthidae (=Latilidae)
12.—Prolatilus jugularis (Val., 1833), (BLANQUILLO; 400 tons).
Inhabitant of the waters between Chiloé and Antofagasta. Consumed
fresh, but it is not a very well liked fish.
290 EIGHTH PACIFIC SCIENCE CONGRESS
Family Carangidae
13.—Trachurus trachurus (L.), (JUREL; 600 tons). Pelagic, cos-
mopolitan, tropical or sub-tropical; approaches the coast during the
Summer, from Chiloé northwards, pursuing in large shoals, the sar-
dines and anchovies.
Family Pomadasyidae
14.-Cilus montti (Delfin, 1900), (CORVINA; 1000 tons). Found
from Chiloé to Tarapaca; abundant mostly during Spring and Summer.
15.—Isacia conceptionis (Cuv., 1830), (CABINZA; 400 tons). From
the Gulf of Arauco northwards; like the previous species, is more
abundant in the Spring and Summer.
16.—Pomadasys schyvi (Steind., 1902), RONCADOR.
17.—Anisotremus scapularis (Tschudi, 1843), (SARGO).
Family Sciaenidae
18.—Sciaena deliciosa (Vschudi, 1845), (AYANQUE),.
These three later species come from Peru; they are caught from
Antofagasta northwards, and are very popular.
19.—Menticirrhus ophicephalus (Jen., 1842), (PICHIGUEN).
20.—Micropogon furniert (Desm., 1823).
These two species are caught in small quantities; are consumed
fresh and are very much liked in their restricted area of distribution,
which extends from Valparaiso to Chanaral.
Family Labridae
21.—Pimelometopon maculatus (Perez-Canto, 1886), (PEJE-PER-
RO). Gulf of Arauco to Iquique; consumed fresh.
22.—Pimelometopon darwinit (Jen., 1842), (MULATO). From An-
tofagasta northwards. It is mostly caught in Tarapaca and is consumed
fresh.
23.—Graus nigra (Philippi, 1887), (VIEJA). Very much esteemed
for fresh consumption in its limited area of distribution, which extends
from Coquimbo (30°S) to Colchagua (34°S).
Family A plodactylidae
24.-Aplodactylus punctatus (Cuv. et Val. 1831), (JERGUILLA).
Found in the area between the Gulf of Arauco and Peru. It is a fish
about 35 cms. long, very little appreciated and consumed almost only by
the fishermen.
Family Cheilodactylidae
25.—Cheilodactylus variegatus (Cuv. et Val., 1835), (PINTADILLA).
26.—C. antonii (Val. 1833), (BILAGAY). Fish of medium size
and bright colors, characteristic of the coastal water from Valparaiso
COMMERCIALLY IMPORTANT FISHES OF CHILE 291
northwards. ‘The fishermen like it in view of the good quality of its
flesh; however, it is caught only in small quantities.
Family Notothenidae
27.—Eleginops maclovinus (Val., 1830), (ROBALO; 2000 tons).
Found from Tierra del Fuego to Valparaiso. Inhabits the waters along
the beaches and enters in the river estuaries; it is the fish of Magellanic
origin of greatest commercial value; abundant all year round in its
original area, offering possibilities for canning. It is presently consumed
fresh, salted and smoked.
Sub-Order BLENNIOIDEI
Family Clinidae
28.—Callichinus geniguttatus (Val., 1836), (TOMOLLO; 25 tons).
Magellan to Antofagasta. It is of average size; inhabits shallow waters
in rocky beaches; its flesh is of good quality and is consumed fresh.
Family Mugiloididae
29.—Mugiloides chilensis (Mol., 1782), (ROLLIZO). Found from
Magellan to Peru; grows up to 80 cms., and has a thick body and good
quality flesh.
30.—Auchenionchus variolosus (Val., 1836), (TRAMBOLLO).
Found from Tierra del Fuego to Iquique; very much alike the previous
species in its aspect and quality.
Sub-Order OPHIDIOIDEI
Family Ophididae
31.—Genypterus chilensis (Guich., 1848), (CONGRIO COLORADO;
1500 tons). Found from Tierra del Fuego to Peru; it is the most liked
fish in the central region of Chile; fished all year round and consumed
fresh like the other following species. Inhabitant of rocky bottoms.
32.—G. blacodes (Schn., 1801), (CONGRIO NEGRO; 2000 tons).
Found from Antofagasta to Tierra del Fuego; very much like the above
species, but less appreciated as food. Its fishery has diminished in latter
years.
33.-G. maculatus (Tschudi, 1846), (CONGRIO DORADO; 400 tons).
It has been caught for six years only in a canyon of the continental
shelf near Talcahuano.
Sub-Order SCOMBROIDEI
Family Gempylidae
34.—Thyrsites atun (Euphr., 1791).
35.—Thyrsitops leprdopodes (Cuv., 1830).
292 EIGHTH PACIFIC SCIENCE CONGRESS
These two species are very much alike, and are known by the
common name of SIERRA; they are pelagic fish which reach the coast
in great quantities, from Coquimbo southwards during the Summer
months. ‘They are of very good quality and are consumed fresh and
smoked. Maintain a considerable fishery (5000 tons).
Family Scombridae
36.—Thunnus macropterus (Schleg., 1850), (ATUN DE ALETA
AMARILLA; 2000 tons). It is caught all year round from Tocopilla
northwards, outside of the coastal current. It is tinned in the canneries
of Iquique.
37.-Germo alalunga (Bonnat., 1788), (ATUN DE ALETA LARGA;
500 tons). From the tropical and sub-tropical Pacific it reaches, during
the Summer months, the coasts of Valparaiso, where it is mostly
consumed fresh.
38.—Katsuwonus pelamys (L.), (CACHURETA). It is found in
the waters outside of the coastal current, from Huasco (28°27’S) north-
wards, and it is caught in comparatively small quantities.
39.—Sarda chilensis (Cuv. et Val., 1851), (BONITO; 4000 tons). It
is found in great quantities along the coasts of Antofagasta and Tara-
paca, and is the fish which constitutes the basis of the canning industry
of northern Chile.
40.—Pneumatophorus peruanus (Jordan and Hubbs, 1925), (CA-
BALLA). It is of small size and it is abundant in the coast of Tarapaca
where it is caught in large quantities.
Family Xiphidae
41.—Xiphias gladius (L.), (PEZ ESPADA; 1000 tons). This is a
cosmopolitan species of warm seas which is abundant in northern
Chilean waters. It is mostly exported frozen to the United States of
America.
Sub-Order STROMATEOIDEI
Family Stromateidae
42.—Stromateus maculatus (Cuv. et Val., 1833), (PAMPANITO).
From Tierra del Fuego to Coquimbo. Small; it is caught in limited
quantities and is liked by the fishermen.
Family Nomeidae
43.—Seriolella porosa (Guich., 1848), (COJINOVA; 400 tons).
From Magellan to Tarapaca; found gathered in small schools during the
Summer pursuing the sardines.
COMMERCIALLY IMPORTANT FISHES OF CHILE 293
Sub-Order MUGILOIDEI
Family Mugilidae
44.-Mugil cephalus (L.), (LISA; 100 tons). Lives in schools near
the beaches, and enters the estuaries of the rivers of the central region,
where it is sometimes found in extraordinary quantities.
Family Atherinidae
45.—Austromenidia laticlavia (Val., 1835).
46.—A. regia (Humboldt, 1833).
The numerous Chilean species of this family, known by the com-
mon name of PEJERREYKES, constitute a systematic problem not yet
solved. ‘They are found all over the Chilean coast as well as in fresh
water. ‘They are very much appreciated and the annual catch is about
500 tons.
ORDER GOBIESOCIFORMS
Family Gobiesocidae
47.—Syciases sanguineus (Muller et Troschel, 1843).
48.—S. chilensis (Brisout de Barneville, 1846).
49.—Sycyogaster marmoratus (Jen., 1842).
These three species live attached to the rocks in the breakers area,
from Chiloé as far as Peru. ‘They are known by the common name of
PEJE-SAPOS, and the fine flesh is very much appreciated.
ORDER BATRACHOIDIFORMS
Family Batrachoididae
50.—_Aphos porosus (Cuv. et Val., 1837), (BAGRE DE MAR).
Reaches the coast to spawn in the fissures of the rocks near the inter-
tidal zone, around the middle of Spring, and leave the coast by the
end of the Summer. During this period it is caught in large quantities
in its lurking places to the end of poles. Its flesh is of excellent quality,
but it is very little known in the market.
OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA
By N. K. PANIKKAR
Central Marine Fisheries Research Station
Mandapam, South India
EARLIER WorK
Although earlier investigations in Indian Seas were conducted by
the British Naval Vessels from 1832 to 1862, serious attempts to study
Indian waters were commenced only in 1872 with the inauguration of
the Indian Marine Survey. The surgeon-naturalists attached to the
survey ships were really the pioneers in marine studies of Indian waters.
The Marine Survey was placed on a more permanent footing when the
survey ship “INVESTIGATOR” was built during 1879 to 1880 and it is
of interest to record that some of the apparatus used in this ship for
work in Indian waters originally came from the gear used by H.M.S.
“Challenger.” ‘The interest evinced in deep sea life by the Challenger
Expedition was reflected in the special attention given to deep sea
organisms of the Indian Ocean. Except for soundings and temperatures,
the observations made were largely biological.
SEWELL’S WorRK ON “INVESTIGATOR”
In place of the “INVESTIGATOR I’, a new ship of the same name
was built and commissioned in 1908 commencing a new phase in
oceanographic work in Indian waters with special reference to the tem-
perature and salinity distributions up to a depth of 500 fathoms
initiated by Sewell, who joined the ship in 1910. ‘The work of Sewell
on “INVESTIGATOR” continued till 1925 with the exception of a break
of some years between 1914 and 1921 owing to World War I. Sewell’s
work brought out the general picture of hydrological features of the
ocean. In a series of contributions published by the Asiatic Society of
Bengal in 1925-35, the geography of the Andaman Basin, the nature
of the sea bed and of the deep sea deposits of the Andaman Sea and the
Bay of Bengal, the maritime meteorology of the Indian Seas, the tempera-
ture and salinity of the coastal and deeper waters of the Bay of Bengal
and Andaman Sea, the topography of the Laccadive Sea and the coral
formations in Indian waters were dealt with by Sewell. Additional
oceanographic data were also obtained during this period from the re-
sults of the German Deep Sea Expedition “VALDIVIA” (1898-99) and
294
OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA 295
the Danish Dana Expeditions (1920-22) and the Dutch Snellius Expedi-
tion (1929), and to a smaller extent by traverses made by other survey
ships.
Joun Murray EXPEDITION
The third phase in the progress of Indian Oceanography relates to
the period covered by the John Murray Expedition to the Indian
Ocean on the research vessel “MABAHISS” led by Sewell. The region
especially chosen was the Arabian Sea, to the west of Maldive and Lac-
cadive Archipelago, in continuation of the “INVESTIGATOR” work.
The expedition was able to confirm some of the findings of the Dana
on the submarine contours and it brought evidence of the presence of
submarine ridges running parallel to the Rift Valley system. ‘The
changes in the distribution of fauna in regions of the Arabian Sea were
also clearly shown by the work of the John Murray Expedition, and a
noteworthy discovery was made of the existence of large azoic areas off
Arabia probably connected with petroleum formation. ‘The results ob-
tained by the John Murray Expedition have been dealt with in various
volumes which have already come out, but the principal findings have
been dealt with by Sewell in various papers.
FEATURES OF THE INDIAN OCEAN
Our present knowledge of the Indian Ocean has been summarized
by Schott (1935), Sewell (1937), and Sverdrup et al. (1950). The
fact that oceanographic information relating to the Indian Ocean is
imperfect has been often stressed and with more intensive work it is
possible that some of the concepts now current may require modification.
This is especially so for that part of the Indian Ocean south of the
Equator. The Northern part of the ocean is broadly divided into the
Arabian Sea and the Bay of Bengal, each with further geographical
sub-divisions. The topography of the Arabian Sea is characterized by
the existence of a long series of submarine ranges, the Carlesberg Ridge
beginning from the region of the island of Socotra and Gape Gardafui
’ and extending to the southeast along the Chagos Archipelago and fur-
ther south to the Island of Rodriguez. To the southwest of the Carles-
berg Ridge and lying parallel to it lies the Mascarane Bank covering
the Islands of Seychelles and Mauritius together with a series of reefs.
To the north, the Carlesberg Ridge is continued by a different forma-
tion in the direction of Arabia and the Gulf of Oman; this ridge which
is considered as the submarine continuation of the Kirthar Range of
Sind is the Murray Ridge. The geology of these ridges and the sea
floor require much further study before their origin could be established
296 EIGHTH PACIFIC SCIENCE CONGRESS
with certainty. In the Bay of Bengal a north to south range, the Car-
penter’s Ridge, which probably is of volcanic origin, is situated to the
west of the Andaman-Nicobar chain of islands. ‘The mouths of the
Indus in the Arabian Sea and the Ganga-Brahmaputra at the head of
the Bay of Bengal have given rise to deep submarine gulleys (Indus
Swatch and Swatch of no ground). ‘The presence of the submarine
ridges and gulleys substantially influences the circulation in the North-
ern Sector of the Indian Ocean. Further, there are widespread forma-
tions of coral reefs of the fringing and atoll types throughout the area
except on the two sides of the Indian peninsula, although reefs are
prominent around southernmost India and Ceylon, the Andaman-Nico-
bar group and the Laccadive-Maldive group. ‘The reasons for their ab-
sence in most parts of the Indian Coast have not been satisfactorily
explained, although it is usually attributed to estuarine influences and
silting on the east coast of India and to the upwelling of colder waters
on the west coast of India (Sewell, 1937).
Hydrologically the Bay of Bengal and the Arabian Sea present
substantially different features and a careful study and interpretation
of these differences might well explain the enormous disparity in fish
production between the western and eastern coasts of India, the former
contributing to more than two thirds of the total. The Bay of Bengal
waters are generally less saline owing to the influence of the large rivers
that empty into it. The eastern coast is also characterized by a well-
developed estuarine fauna. On the other hand the salinity of the
Arabian Sea waters is distinctly higher and the waters generally are of
an oceanic character. Owing probably to the upwelling of deeper
waters to the surface, the vertical mixing facilitated by the Carlesberg
and Murray ridges and the turbulence resulting from strong S. W. Mon-
soon winds, the Arabian Sea waters appear to be richer in nutrients
having extensive areas of high productivity. It is noteworthy that shoals
of plankton feeding fishes like the oil sardine of Malabar (Sardinella
longiceps) and the Indian mackerel (Rastrelliger kanagurta) largely
contribute to the west coast fisheries of India.
Post War INTEREST IN FISHERIES AND OCEANOGRAPHY
It may be said that the work carried out so far did not form part
of any comprehensive programme for the investigation of Indian waters.
Collection of further information has continued through the agency of
survey ships and subsequent expeditions like that of the Discovery II
and the Galathea. With the end of World War II, India, like many
other nations of the world, was faced with problems of acute food short-
age, and one of the subjects that received governmental attention was
OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA 297
the development of marine fisheries. It is natural that in connection
with fisheries programmes a considerable amount of interest was also
evinced in the further pursuit of oceanographical studies as an aid to
the proper exploitation of marine fishery resources. A very small part
of biological and chemical studies as a necessary ancillary to the de-
velopment of fishery investigations was initiated in 1948 when arrange-
ments for the systematic collection of hydrological data at selected
fishery centres were made. ‘These attempts to obtain hydrological data
have been purely from the standpoint of fishery work and it cannot be
said that they have been carried out in any systematic manner in the
absence of a Fishery Research Vessel for regular cruising.
It is well-known that the arrival and departure of shoals of fish in
any definite area are largely governed by their movements connected
with their feeding and spawning habits, which are most intimately
related to the physical and chemical properties of the sea water in which
the shoals are located. In the sea there are periodical fluctuations in
the physico-chemical conditions which may be annual, seasonal or even
diurnal; these fluctuations are the combined results of the action of
various meteorological and hydrodynamical factors. In addition to these
more or less normal variations there may also be abnormal variations
caused by geophysical disturbances or by factors unknown to us at the
present time. A very systematic approach to these various problems is
necessary to obtain a correct picture of sea fisheries of the Indian coast,
which are largely seasonal and some of which, like sardines, show large
variations from year to year.
Indian marine fisheries are largely seasonal in character and the
causes governing the movements of shoaling fish and the reasons for the
failure or shift of seasons of a given fishery are at present unknown.
Similarly the fishing grounds have not been charted, though a beginning
has been made in this direction for areas around Bombay. The area
now exploited for sea fishing includes only the narrow coastal zone of
five to six miles from the shore. Power vessels to exploit the off-shore
fisheries have begun operations on a pilot scale in Bombay under the
aegis of the Government of India and in Calcutta by the Government
of West Bengal. In the not too distant future, it is expected that more
vessels will be put into operation from different centres like Cochin,
Madras and Visakhapatnam. ‘The work of exploration of off-shore
fishery resources and the charting of fishing grounds is one which calls
for help from oceanographical studies as data on movements and com-
position of the water masses would be extremely useful.
298 EIGHTH PACIFIC SCIENCE CONGRESS
CENTRAL BOARD OF GEOPHYSICS
The Government of India constituted the Central Board of Geo-
physics in 1949 and an Oceanographical Committee of the Central
Board of Geophysics reviews the problems of oceanographical studies
in India from time to time with the ultimate object of setting up an
Institute of Oceanography. ‘This probably marks the first attempt in
the country to think in terms of oceanography as an independent sci-
ence which needs pursuit for its own sake without being subservient
to the applied aspects of Fisheries, Harbour development, Coastal ero-
sion, ‘Tide Prediction, Survey and Navigation. It may be recalled that
the Survey of India has for a long time been carrying out prediction of
tides for thirty-nine ports from Aden to Singapore and it is also re-
sponsible for the mean sea level determinations. Expansion of tidal
work is also contemplated by the Survey of India by placing tide gauges
at most of the important ports and carrying out corresponding meteoro-
logical surveys with the help of the India Meteorological Department.
EXTENT OF AVAILABLE DATA
The information on oceanographical topics available in India
would therefore comprise (1) Salinity and temperature distributions as
recorded by previous expeditions and part of which work is being
continued with reference to Fisheries by the Central Marine Fisheries
Research Station at Mandapam with the help of Fishery Naval and
Merchant Vessels operating in Indian waters; (2) Data relating to tides,
mean sea level and other physical aspects available with the Survey of
India; and (3) Data on maritime meteorology available with the India
Meteorological Department.
An extremely useful compilation of sea temperature, currents and
meteorological data has been published by the Netherlands Meteoro-
logical Institute in the form of an Atlas in 1952.
BEGINNINGS OF FISHERIES RESEARCH
Early attempts relating to research on marine fisheries of India
were directed to experimental trawling operations by ships belonging
to the Madras, Bengal and Bombay Governments and the scientific
work relating to the biology of the Oil Sardine of the Malabar Coast.
The trawling operations were commercially unsuccessful and_ fishery
work in most provinces suffered neglect during the periods of economic
depression that followed the first World War. ‘The interest in the
Sardine fishery of the west coast of India continued because of the
disasters which this fishery suffered following the many successful years
OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA 299
for Sardines which led to the production of sardine oil becoming an
important industry. Owing to the inadequacy of staff, lack of sufficient
funds to carry out investigations with thoroughness, and the position of
Fisheries as a Provincial Subject creating administrative problems when
a fishery extends to two or more states, these efforts often lacked
continuity. The first decision to tackle the marine fisheries investigation
on an All-India basis was taken by the Government of India with the
starting of the Central Marine Fisheries Research Station in 1947.
CENTRAL MARINE FISHERIES STATION
This Central Institute was started in February 1947 for handling
marine fisheries research on an All-India basis with temporary head-
quarters in the Biological Laboratories of Madras University until the
permanent headquarters at Mandapam were ready for occupation.
Buildings originally put up as a Naval Hospital by the Defense Depart-
ment during World War II were converted into laboratories and tem-
porary residential accommodation for the staff. Subsequently an aqua-
rium was built with facilities for keeping organisms alive in circulating
sea water and fittings to the laboratories were carried out. In addition
to the headquarters station, there is a subsidiary research station at
Kozhikode to deal with the special fisheries problems of the West Coast
of India, and research units at Karwar in the Bombay State to deal with
the mackerel fishery, at Narakkal in Travancore-Cochin to deal with the
prawn fisheries and prawn farming operations, at Madras for handling
studies on edible Mollusca and at Bombay for carrying out investiga-
tions on off-shore fisheries. In order to collect fishery data from the
long coast-line of India, fishery survey assistants have been posted at
twelve centres representative of the various divisions of the Indian
coast-line extending from Kathiawar to West Bengal. The data gathered
are analysed and computed at Headquarters, setting up for the first time
a machinery for the collection of All-India marine fishery statistics.
PROGRAMMES OF MARINE FISHERIES RESEARCH
The work of the institution is broadly divided into four categories,
Fishery Survey, Fishery Biology, Marine Biology and General Physiol-
ogy. Fishery Survey aims at assessing the marine fishery resources by
computing fish landings and biological composition of catches to see
if the marine fisheries in general are under- or over-utilized. Scientific
study of exploratory work of the deep sea fishing vessels forms an essen-
tial part of the survey programme. ‘The studies relating to Fishery
Biology deal with the fish stocks, special habits, distribution, life-histo-
ries and such aspects of fish life as have intimate bearing on fisheries
300 EIGHTH PACIFIC SCIENCE CONGRESS
problems. The major fisheries of India like the Sardines, the Mackerel,
the Sharks and other less known categories of fishes are all investigated
in detail in an attempt to understand the causes governing their abun-
dance, and the efficiency with which the fish are caught and utilized.
Subsidiary fishery resources like the prawns, the oysters, clams, etc. are
also receiving close attention. Sea weeds which occur in considerable
abundance in the sea and form a valuable raw material for the produc-
tion of agar and other industrial products, are being investigated in
detail to determine the extent of the resources. The third important
category of investigations come within the field of Marine Biology deal-
ing with the factors connected with the abundance of smaller forms of
plant and animal life which ultimately form the food ‘of fish. This is
also correlated with studies on the chemistry of sea-water with a view
to understanding seasonal changes in the occurrence of nutrient salts.
Bacteriology of sea-water and fish products is also investigated with a
view to arriving at enforceable standards in the handling of fish prod-
ucts. The physiology of fish and other commercially important forms
of marine life are studied with a view to selecting suitable types that
would be ideal for large-scale culture in coastal areas which could be
developed into marine fish farms. The institution maintains a good
library and a reference collection.
CORRELATION OF OCEANOGRAPHY AND FISHERIES
In the above paragraphs some idea has been given of the ap-
proach to oceanographical and marine fisheries studies in India. ‘There
is need for a standing machinery to collect and integrate synoptic data
on the hydrology and maritime meteorology of the waters that surround
India. The emphasis so far received has been biological and although
marine biological investigations on a considerable scale have been car-
ried out at Visakhapatnam, Madras, Mandapam, Trivandrum, Calicut
and Bombay, the full interpretation of these results has to await more
intensive physical-chemical work. Preliminary chemical data on phos-
phates, nitrates, nitrites and silicates are already available for Madras,
Mandapam and Calicut and it is hoped to extend these further in the
near future. The greatest drawback, however, lies in the fact that stu-
dies have principally been carried out in inshore or neritic waters with
few observations in the open sea. An attempt to obtain a clear picture
of oceanographic conditions in relation to Fisheries has now been
initiated by the Central Marine Fisheries Research Station from Bom-
bay utilizing the facilities of deep sea fishing vessels operating from
that port and especially in view of the excellent results in trawling
operations to the west of Kathiawar, which has now been found to be
OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA 301
one of the richest fishing grounds in India. A new line of work to cor-
relate fishery conditions with oceanography has been developed in the
study of mud banks of the Malabar Coast where it has been established
that the fine silt which settles soon after the southwest monsoon in the
form of a submerged bank acts as a reservoir of nutrient salts, probably
influencing the fisheries of that area. On the physical side, work has
been started by the Indian Navy in the Port of Cochin. There is need
for more detailed coastal surveys and accurate charts and maps for the
entire Indian coast, and for this purpose the surveys which are being
repeatedly carried out by the survey ships will, it is hoped, contribute
a large amount of data.
FUTURE PROSPECTS
Oceanography is an infant science in India as compared with the
status of the subject in the more advanced countries where work has
been in progress for some years. Absence of adequate training facilities
for physical oceanography at Universities and non-availability of suit-
able research vessels for oceanic work constitute the major obstacles to
progress, but there is every reason to think that these will be overcome.
The Andhra University on the East Coast of India has already formed
a Department of Geophysics, and has initiated some work on physical
and biological oceanography at Visakhapatnam. A few Indian Re-
search Scholars are being trained abroad on the subject. Research
Vessels for oceanographic and fisheries work are likely to become avail-
able under the Five-Year National Plan of the Government of India
and substantial additions to equipment available for marine work are
now being made at several centres of Research. These developments
in a country situated in one of the least explored of oceans will be
watched with interest by all students of Marine Science.
REFERENCES
EKMAN, 8S. 1953. Zoogeography of the Sea. Sidgwick & Jackson, London.
GULATEE, B. L. 1952. Tidal work in India. Assoc. Oceanogr. Phys. Proc.
Verb. No. 5, 178.
JOHN MurrAy EXPEDITION. Various Scientific reports.
KONINKLIJK NEDERLANDS METEOROLOGISCH INSTITUUT No. 185. 1950. Indian
Ocean Oceanographic and Meteorological Data.
PANIKKAR, N. K. 19538. Fisheries Research in India—Pt. I. J. Bombay Nat.
Hist. Soc., 50.
ScHOTT, G. 1985. Geographie und Oceanographie des Indischen und Stillen
Ozeans. Hamburg.
SESHAPPA, G. 1953. Phosphate content of mud banks along the Malabar
Coast. Nature, London, 171, 526-27.
302 EIGHTH PACIFIC SCIENCE CONGRESS
SEWELL, R. B. 8. 1925-35. Geographic and Oceanographic Researches in In-
dian waters. Mem. Asiat. Soc. Bengal., Vol. 9.
1987. Oceans round India: in Outline of Field Sciences of India,
Calcutta.
1953. Deep Sea Oceanographic Exploration in Indian Waters.
J. Bombay Nat. Hist. Soc., 50, 705-717.
SVERDRUP, H. U., M. W. JoHNSoN and R. FLEMING. 1942. The Oceans, their
Physics, Chemistry and Biology. Prentice Hall, New York.
OCEANOGRAPHY AND FISHERIES
By G. L. KESTEVEN
Marine Fisheries Section
Food and Agriculture Organization cf the United Nations
Rome, Italy
The contribution of oceanography to fisheries research (which
means research in economic and technical fields as well as in biological
fields) is to be understood only in terms of the applied character of
fisheries science: an effort is made in the following paragraphs to ex-
pound the implications of this statement. However, it is desired here to
stress a principal consequence of this position, namely that it brings
upon the fishery scientist an obligation to exercise a keen discrimina-
tion, and to undertake a frequent scrutiny of his activities, to determine
whether they will stand a test of their applicability to real fishery
problems.
1. SoME DEFINITIONS
The term Indo-Pacific is used in the sense in which it is employed
by the Indo-Pacific Fisheries Council, namely, to signify the zoogeo-
graphic area occupied by the warm-water marine fauna which is var-
iously described as Indo-Pacific, Indo-West-Pacific (Ekman), and Indo-
Australian (Weber and de Beaufort), the core of which is constituted
by the Indonesian Archipelago. The term oceanography is taken to be
the correlative of limnology and thus with that term to comprehend
the whole of the scientific work bearing upon the hydrosphere with
biological objective, or of biological use. ‘This definition derives au-
thority from many works from among which perhaps that monumental,
and already classical work “The Oceans’, by Sverdrup, Johnson and
Fleming, may be chosen for citation. The validity of regarding oceanog-
raphy as correlative of limnology may be found in the comprehensive-
ness of the latter, as set out in such standard periodicals as the Revue
der Internationale Gesammte Hydrobiologie and also in the standard
text by Welch, which uses that term as title.
It is to be stipulated that we reject the restriction imposed upon the
term by some workers who regard it as concerned only with physical
and chemical features of the oceans, and even as especially the pre-
occupation of naval research establishments. Whilst, of course, there can
be no challenge of their right to choose this usage, their attention may
303
304 EIGHTH PACIFIC SCIENCE CONGRESS
well be drawn to the confusion which they create, especially since they
do not offer us any alternative correlative of limnology.
Oceanography is used by us to signify the study of the oceans in
respect of themselves as water masses and of the biota which inhabit
them; if not qualified, as it is in expressions such as ‘fisheries biology’,
it is a pure science with no limitations upon the range or detail of the
subject matter of its enquiry. A qualifying term, such as “fishery”,
signifies an orientation of the enquiries and a limitation of the field,
and not a specialized extension; thus, fisheries oceanography is that in-
vestigation of the physico-chemical and biotic properties of the oceans
required by fishery science—it does not mean oceanography which has
swallowed fisheries research!
2. GENERAL CONSIDERATION
In a general way we may say that oceanography holds a relationship
to fisheries corresponding to that which meteorology holds to agricul-
ture. But we must go further and describe it also as the ‘soil-science’
of fisheries. “These two aspects were discussed by Tait, in his Auckland
lectures, from the points of view of physical and chemical properties
of the sea, respectively, in relation of fishes. “The more general, as well
as more particular aspects of relations of aquatic organisms to the phys-
ical and chemical factors of their environment, have been described
in the new voluminous literature of ecology. In this paper I wish to
make a plea, both for a special fisheries view of these relations and, at
the same time, for further and more detailed investigations along what
might be described as the classical approach to animal physiology and
ecology.
The programme of fishery biology traverses, in a general sense, six
principal phases, a brief description of which I quote from a recent
paper I presented to the General Fishery Council for the Mediterranean.
“Firstly, if the area in which the biologist is working is virgin a
survey must be made to determine the general characteristics of the
area and of its fish stocks; the principal compositional features of the
stocks must be described. For most of the present fishable areas informa-
tion such as this has been accumulated in the course of fishing opera-
tions and from work in marine biology; in such cases, a late starting
programme in fishery biology must first collate all such information.
‘Secondly, the general features of the stocks of the species to be
investigated must be determined. ‘The species must be correctly iden-
tified, and the continuity and taxonomic homogeneity of these stocks
must be examined. ‘This work may or may not require the refined
; OCEANOGRAPHY AND FISHERIES 305
taxonomic study known as racial investigations, but it is im any case
a distribution study which must take reference to details in the bio-
nomics of the species.
“Thirdly, the bionomics of the species must be discovered, that is
the general-life-history, ontogenology (embryology, growth, and geron-
tology), including feeding habits, reproduction and migratory habits.
“Fourthly, the composition of the stocks is to be determined and,
if the stocks exist in separate units, this determination must be made
for each separately. ‘This compositional study concerns the age, sex,
size, and maturity and other groups of the population.
“This analysis generally reveals a fluctuation from year to year in
composition of the stocks. Frequently there is also considerable varia-
tion from area to area and between distinct segments of the stock. This
study should see, not only to describe the composition and its fluctua-
tion, but also to discover the causes of these fluctuations and, if possible,
to evolve a system of prediction of the appearance of the fluctuations.
“Fifthly, following directly out of the fourth stage, there is to be
a measurement of the properties of the population. ‘These properties
are potentials for growth and reproductions, and viability as a comple-
ment to the mortality which the stock sustains. In this stage there is
affected a considerable concentration of information since not only are
data on the bionomics and composition of the stocks to be reduced into
expressions summarizing the consequence of these structural features,
but there must also be a reference to physiological, physical and other
data concerning the factors which determine the properties of the pop-
ulation as a whole. This work should also aim at a prediction system.
“Sixthly, the fishery biologist must then collaborate with the fishery
economist and fishery technologist in applying the general theory of
fishing to give mathematical expression to the relations between the
properties of the population and the effect of fishing operations.”
The essential feature of this programme is that it is concerned with
populations: its purpose is to develop a detailed description of the
population as a whole and of the response of the properties of the popu-
lation to changes in its environment, including among such changes,
of course, those in fishing intensity.
The biologists’ responsibility in respect of these populations is one
or the other of two kinds, which may be summed up in two questions:
Firstly, what type of population and where? Secondly, of what abun-
dance? ‘The first question belongs in the main to the exploratory stage,
the second to the management stage. In a way, also, these questions
correspond to the different enquiries concerning abundance; those
which relate to the availability of the fish to fishing operations, and
306 EIGHTH PACIFIC SCIENCE CONGRESS
those which relate to the real abundance of the stock; and these in turn
are covered respectively by the first three and the last three of the
stages listed above.
3. OCEANOGRAPHY AND THE DISTRIBUTION OF FISH
In its broadest sense this is a question primarily of marine zoo-
geography, but for the fishery biologist the enquiry must press far
deeper, since, in point of fact, for each species of commercial impor-
tance he seeks to establish the ontogenetic distribution patterns and,
moreover, the seasonal, annual, and even secular modulations of these.
The great oceanographic cruises, of the Challenger and of others, have
since established the major features of our picture of marine zoogeo-
graphy and yet withal there remains much to be done to enable us to
evaluate unexploited areas and to be able to give fishermen the in-
formation on which they might plan the development of fishing
operations.
The zoogeographic account of the distribution of marine faunas is
in effect a generalized one referring to groups of species and to indi-
vidual species which characterise the fauna and serve as indicators of
identified conditions. The distribution patterns referred to in the zoo-
geographic account indicate the broadest limits within which the faunas
are observed to occur.
The more restricted limits within which the various ontogenetic
stages move are not of as great importance to zoogeography as they said
their seasonal and other modulations are to fisheries. But the greater
pattern and its component parts are both the grosser manifestation of
the reaction of the individual organisms to the various elements of its
environment at the behest of its own physiology. ‘The general adjust-
ment of the organism to its medium in respect of its respiratory and
osmo-regulatory requirements set the general limits within which it can
move differences, in these requirements, between ontogenetic stages
may, theoretically, give separate distributions to these stages. The nu-
tritional requirements and peculiar needs in respect of reproductive
habits, further complicate the picture as the organisms undertake feed-
ing and reproduction migrations in search of the situations where the
necessary conditions are satisfied. It is perhaps no misrepresentation to
say that in the first part of this enquiry, the task is to describe the dis-
tribution of the first and the conditions under which they are found,
whilst, in the second part, the task is to find means of predicting where
these conditions will be found—as a means to predicting where the fish
will be. It must be stressed, however, that the accurate account of dis-
tribution requires elucidation of the keenomics of the species.
OCEANOGRAPHY AND FISHERIES 307
At this point we are concerned only with the types of fauna found
in various situations, with the task of characterizing an area in respect
of the composition of its fauna and, for situations whose fauna is known,
with evolving means of predicting variations in the distribution of ele-
ments of that fauna and of ontogenetic stages of those elements.
The role of oceanography in this phase of the programme emerges
very clearly; it must first furnish the description of the physical, chem-
ical and biotic properties of the water masses and in this way it cor-
responds to soil science coupled with climatology. Then, when the
distribution patterns are revealed, the role of oceanography corresponds
to that of meteorology in furnishing predictions as to the conditions
which are likely to be found, and the task of the fishery biologist then
is to predict the behavioral response of the fish stocks to such conditions.
4. OCEANOGRAPHY AND THE ABUNDANCE OF FIsH
In this part of the programme we may consider three types of prob-
lems having common basis. We are concerned with the natural abun-
dance of fish in an area, a problem which has practical meaning only for
unexploited areas, although a method of estimating potential natural
abundance of an exploited stock might solve many of the problems
concerning abundance under conditions of exploitation. Next we are
concerned with the fluctuations in abundance which have manifested
themselves in all exploited stocks, whatever the degree of exploitation.
Finally, we are concerned with the special problem of the effect of fish-
ing operations on the abundance of the stock.
The measurements of natural abundance of stocks in virgin areas
is a task of peculiar difficulty which demonstrates, perhaps more than
anything else, the special character of the work of fisheries science and
the abstruseness of its problems. A simple example will serve to indi-
cate the nature of the problem and the difficulties. Somali fishermen
have for many years been catching tunas off the Somali coast, and for
some years a few small canneries have been processing this catch for
export market. The canneries would like to expand their operations
and therefore require to increase their catch of tuna; the question is:
do substantial stocks of tuna, accessible to fishing craft operating from
Somalia, inhabit the waters on the Arabian Sea east of Somalia, or, are
the occurrences from which the fishermen have made their catch merely
sporadic invasions from a principal area lying somewhat remotely from
Somalia? This, it will be noted, is not a simple distribution question,
for the tuna are well known to appear in these waters. It might be a
question of ontogenetic distribution pattern and the determination of
this possibility could lead to development of a system of prediction of
308 EIGHTH PACIFIC SCIENCE CONGRESS
the times and conditions under which these occurrences take place, and
even of the fluctuations in relative numbers of fish appearing from time
to time. But this would still be insufficient: the cannery operators
need to have some indication of the level of abundance in order to be
able to decide the amount of fishing equipment (craft and gear) which
could be brought to bear on the stocks, and thence the amount of pro-
cessing equipment which would be required to handle the catch.
There are probably two broad avenues of approach to this prob-
lem. One is by way of evaluation of the area in terms of basic pro-
ductivity and measurement of food chains. This would be possible
only for stocks endemic to the area and not to transients. The other
approach is by way of special sampling which, in the case of pelagic
stocks, may include aerial observation. It may be noted that in this field
of work there is urgent need to elaborate and improve the methodology
of searching and sampling, and that in such improved methods, even
greater use must be made of reference to oceanographic factors as de-
terminants of the behaviour of the fish.
In the more general sense of the productivity of an area, the ocea-
nographer must take a leading role, and the task of the fishery biologist
is to develop the understanding of the nutrition of the economic species
in order to be able to use the data on food availability.
We now turn to the other two problems concerning abundance.
The structure of the problem was symbolized by Russel, in his well-
-known equation, which says that the difference in a stock of fish, be-
tween one season and another, can be represented by the balance
between.
Growth + Reproduction and Natural Mortality + Fishing Mor-
tality. We may take these four elements as the plan for our enquiry.
Growth:—The growth of any individual may be taken to be the
result of the operation of factors which may be considered in three
groups—genetic, food supply, and the environmental factors affecting
food procurement and the subsequent metabolism; between these arise
interactions. In the past fishery biology has concerned itself chiefly with
measuring and describing the ontogenetic manifestations of growth: it
has made little analysis of growth itself as physiological process. ‘The
initial approach made by fishery biology to growth has furnished a
useful description of growth phenomena at what might be called their
grosser level, and some attempt has been made to measure the relations
between these phenomena on the one hand, and food availability and
environmental conditions on the other. Whether much further progress
can be made along this line before more detailed enquiry is made into
the physiology of growth might be questioned, but both types of enquiry
OCEANOGRAPHY AND FISHERIES 309
require much information from oceanography on the environment of
the fish. The first information is that concerning food availability; the
second is that concerning temperature, salinity, trace elements and biotic
factors which influence the procurement of food it ingests. But the work
of fishery biology has been concerned generally with estimates of aver-
age growth in populations, and with this as a means of characterizing
year-classes and the conditions prevailing from year to year. Recent
work has carried the theory further to attempt to use those data on
growth as a means of estimating the biomass production of the popula-
tion as a whole. Such work will accomplish a practical effectiveness,
however, only after the underlying physiology of nutrition and growth
have been studied further, and this will mean, as in the study of nutri-
tion and growth of domestic animals, that there must be controlled ex-
periments in which both food supply and environmental factors are at
least precisely measured if not actually controlled.
In this field of enquiry, taking it to be the responsibility of fishery
biology to measure the growth of the population, the contribution of
oceanography is two fold: initially, in aiding the description and analysis
of these systems; subsequently, in providing data for a prediction sys-
tem. In the initial phase the contribution is of data on all factors which
might directly or indirectly affect the nutrition and growth of the fish.
In the prediction phase, the data would concern certain critical factors.
Reproduction:—Although in the fishing theory equation this term
refers essentially to recruitment into fishable stocks, the fishery biologist
has some concern with the whole range of phenomena which lead to
the reproductive act and those which lead from that act to recruitment.
That is to say, there is a concern with sex ratios and fecundity, with
length and age at first maturity, and (within each season) of the
maturation of the gonads, with the spawning act itself (including fer-
tilization), with embryonic development and hatching, with larval and
post-larval development, and with growth and survival through these
and the young-fish stages. Some workers consider that the only practi-
cable approach to the problem of replenishment of the stock is by way
of measurement of recruitment as it is taking place, or of the potential
recruits shortly before they enter the fishery. Other workers contend
that it is possible to enter more deeply into the system and to attempt
some measurement of the series which connects spawners with recruits.
Among these latter there are some who believe that, although in gen-
eral the number of eggs produced at each spawning is always far in
excess, in numbers, of the number of individuals which survive to be
recruits to the fishery, so that little connection can be found between
the number of eggs spawned and the subsequent recruitment, the brood
310 EIGHTH PACIFIC SCIENCE CONGRESS
strength is, in the main, determined by one or more critical factors at
certain critical points in the life of the brood. Efforts at demonstrating
this hypothesis have aroused some controversy. However, it is unques-
tionable that the sequence described above is closely dependent upon
environmental conditions and that any understanding of it, let alone
any measurement of it or formulation of a prediction system, must make
demands upon oceanography.
Natural Mortality:—This term is perhaps even more recalcitrant
than the other two. We may argue, a priori, that mortality may be
caused by predatism, parasitism, disease, lethal genetic characters, mal-
nutrition, and physical factors such as temperature and salinity extremes,
but there seems to be little prospect yet of measuring the result of
operation of each of these factors separately, or, as an antecedent to that
result, the intensity of each factor. Nevertheless, again we must look
to oceanography to furnish the fishery biologist with some of the in-
formation which he will require in this field. At the present stage
natural mortality must be accepted as a sum arrived at after deducting
measured fishing mortality from estimated total mortality. It might be
possible to correlate variations in natural mortality with variations in
environmental factors and thus to approach both analysis of the causes
and prediction of intensity.
Fishing Mortality:—In this field, oceanography has a small contribu-
tion to make in respect of the influence of weather and sea conditions
on the intensity of fishing operations and their efficiency, but we defer
further consideration of this to Section 5 of this paper.
Fluctuations in Abundance:—A great deal of work has been done in
describing the fluctuations in abundance of exploited stocks and analys-
ing these fluctuations in terms, chiefly, if variations in strength of brood-
classes and in recruitment into fishable stocks. ‘This work can proceed
at one or other of various levels: either with simple description of the
fluctuations and elementary correlation with various environmental
factors—a course which does not promise much reliability in its results;
or with varying degrees of penetration of the analysis into the systems,
with the conviction that if relationships are truly identified, and rela-
tions usefully measured, prediction systems may be evolved with prac-
tical and reliable value.
Fishing Theory:—Perhaps the ultimate objective of fishery science
in respect of fishing operations is to prepare, for each unit fishery, a
description of the fish stocks and of the effect on them of the fishing
operations in order to permit the design of a plan of management of
the fishing operations which will ensure the best exploitation of the
stocks. The description of each unit fishery will be along the lines of
OCEANOGRAPHY AND FISHERIES 311
the Russel equation as discussed above, and the dependence of this work
upon oceanographic inquiry is Clear.
Best exploitation clearly means that which will give the best and
most sustained yields, but in another way it may be signified by the term
“fish husbandry’—a concept which has recently emerged in respect of
marine stocks and which, at least, holds out a goal, even if we should be
ready to find that the end-result might not be as precisely analogous to
animal husbandry as our present speculative thinking imagines it. This
touches upon the possibility that there might be other direct interven-
tion in the stocks besides the fishing operations. Some speculative think-
ing has turned to the possibility of intervening in some of the basic
phenomena of the sea, and there has been experimentation in fertiliza-
tion. The realization of artificial upwellings, or of control of the move-
ments of marine stocks, will depend very largely on the work of the
oceanographers.
5. OCEANOGRAPHY AND FISHING OPERATIONS
The dependence of fishing operations on weather and sea conditions
needs no discussion, either in respect of the effect of environmental
factors on the behaviour of the fish (which determines gear and method)
or of the effect of weather and sea surface conditions on the craft. The
pot to make here is that fishermen need more aid from the oceanog-
raphers by way of predictions of these conditions.
6. DiscUSSION OF THE RELATIONS BETWEEN OCEANOGRAPHY AND FISHERIES
There is really no need to make a case for recognition of the im-
portance to a knowledge of any organism (or population of organisms)
of data concerning its environment, and as oceanography is defined here,
it is the science which will furnish the environmental data required by
the fishery biologist. I do not believe that it can be denied that in fact
fishery science can no more do without oceanography than agricultural
science can do without meteorology. But, whereas oceanography per
se has the entire marine hydrosphere as its field of enquiry, and the
limits are set only by the interest of the worker and the funds, equip-
ment and help available to him, fisheries oceanography is to be defined
strictly according to the area of interest and the kind of problem pre-
sented by the fishery biologist.
It will be clearly seen from the preceding discussion that different
types of oceanographic information are required in the different situa-
tions found in fisheries. Different sets of elements are to be observed,
with different patterns of observation station, and different intensities
of observation at each station according to the nature of the fishery
problems. In the determination of general limits of distribution of a
a2 EIGHTH PACIFIC SCIENCE CONGRESS
fauna, or a species, broad isotherms, isohalines and so forth are sufficient,
but for more detailed description of distribution, a more precise measure-
ment, with much narrower intervals between the iso-lines, is required.
The point which must be made is that the oceanographic programme
for fisheries should be carefully planned with a clear view of what is
required by the biologist’s problem and of the use which he can make
of the material and data which are collected. And perhaps it would not
be dogmatic to say that where resources for oceanographic research are
limited, these should be employed in those situations in which the need
for oceanographic data can at once be formulated, rather than in
broader fields from which the data may be expected to be of use at some
unspecified time in the future.
7. OCEANOGRAPHIC REQUIREMENTS IN THE INDO-PACIFIC
On the basis of the foregoing review, and making use of some of
the criteria proposed for setting limits upon the oceanographic pro-
gramme for fisheries, we may make a brief review of some of the urgent
problems for oceanography in this region.
In the first place it is as well to refer to the important problem of
the basic productivity of tropical waters. This has now become a critical
question, the solution of which would have considerable bearing on
the planning of future development of fisheries. However, it is a long
range problem which, at this stage, stands within the province of the
oceanographer with his more general interest. Moreover, it is probable
that further advances need to be made in perfecting the techniques for
measurement of productivity and in marine biological research on food
chains and the nutrition of marine organisms.
Turning to immediate fishery problems, mention may first be made
of the ‘major’ fisheries of the region, such as for the Rastrelliger spp.
of the Indian and Malayan west coasts, of the Gulf of Siam and of In-
donesia, the Sardinella longiceps in much the same areas, Stolephorus
spp. also in similar areas, Sardinia sp. in Japanese waters, the reef stocks
predominantly of Percomorph species, the Pseudosciaena spp. of the
China Sea, the Flying fishes (Exocoetidia) of the Celebes and those for
the Carangids and Scombroids, more especially within the various island
groups. In respect of each of these fisheries the requirement is for
oceanographic information bearing upon the distribution of the fish,
and the related work concerning the bionomics of each species. In some
cases the broad distribution limits are known and the present problem
is to determine the distribution of ontogenetic stages and to develop
prediction systems; Rastrelliger in the Gulf of Siam, Sardinia in Jap-
anese waters, and Pseudosciaena in the China Sea are in this situation.
OCEANOGRAPHY AND FISHERIES 313
In other cases the situation calls for a more general exploration of dis-
tribution and analysis of compositions; this is especially true of the reef
stocks. In all of these cases there is need of estimates of level of abun-
dance, in none of them, except perhaps the Japanese sardine, does the
present knowledge of the stocks warrant the mounting of oceanographic
programmes appropriate to a true population analysis as described above.
The ioregoing instances are all of well established fisheries which
stand in need of improvement in the knowledge of the biology of the
resources. Of different status are two other broad classes of resources:
the pelagic stocks of the high seas, and the demersal stocks of certain
continental shelf areas. ‘The latter include the continental shelf of
the Indo-Pakistan west coast, of the Bay of Bengal, or the deeper waters
of the Gulfs of Siam and Tonkin, of the South China Sea, and of the
Java and Arufura seas. Although there has been some exploration of
these areas, and in some cases (e.g. off the Saurasthra coast) some sys-
tematic fishing, the knowledge of the areas is generally patchy and in-
complete; as soon as the development plans of the fishery industries of
the adjacent countries warrant, there should be systematic exploration
and survey of these areas, and this work should include the taking of
appropriate oceanographic observations. Similarly, in the case of the
pelagic stocks, survey work must be undertaken at some time and must
include oceanographic observations.
As a final note, I may say that, whatever my remarks above, I do
not underestimate the difficulty which confronts a worker, or a director
of a programme, in determining the limits of the work and the relevance
of different avenues of enquiry which open up as an enquiry develops.
One can only say that this must be left to the perspicacity and honesty
of the worker. One cannot deny the desirability of general oceano-
graphic enquiry, any more than the urgency of particular enquiries,
demanded by economic necessity, can be ignored.
FACTORS IN THE UTILIZATION OF CANADA'S
PACIFIC MARINE RESOURCES
By J. L. Harr
Pacifie Biological Station
Nanaimo, B. C., Canada
In a simple society men use their hands or simple tools to take fish
for their own immediate food needs. In an industrialized society com-
plicated machines are used to catch and prepare fish for shipment and
exchange for other commodities. In any region the extent and char-
acter of the departure from the simple situation depend upon (1) the
qualities and habits of the fish species available, (2) the geography and
meteorology of the region, (3) the technological aptitude of the fisher-
men, and (4) the economic condition of the inhabitants. These factors
are also an influence in the attitude of peoples toward resource utiliza-
tion. ‘Their application to the fishing industry of the Pacific coast of
Canada is discussed in this account.
FisH Usep
Five species of salmon of the genus Oncorhynchus provide more
than half the total value of the Pacific fishery in Canada. The fish are
fat, preserved well by canning, freezing or salting, and are in general
high demand. They differ substantially in life history but all are ana-
dromous, and all attain most of their growth in salt water. On their
spawning migration in summer and autumn all pass through the inlets
and channels of the coast in large and readily captured schools. Thus,
on its spawning migration each species is susceptible to easy depletion
or even extermination by fishing. Human activities add to the natural
hazards of the freshwater life of these fish: dams obstruct rivers; irriga-
tion requirements divert water; impoundments “drown” spawning
grounds; communities and industries pollute streams; logging and agri-
culture result in silted spawning grounds or changes in stream flow.
‘The second ranking fishery on the Canadian Pacific Coast is for
herring (Clupea pallasi). Most of the catch is reduced and shipped to
the markets of the world as oil and meal. Adult and adolescent herring
for the most part spend their summers feeding offshore on the con-
tinental shelf. In autumn and winter they form dense schools and ap-
proach the coast as a preliminary to spawning in shallow water and on
the beaches in March. The migrating aggregations are very vulnerable
314
UTILIZATION OF CANADA’S PACIFIC MARINE RESOURCES 315
to large scale capture. ‘This suggests that intensive fishing operations
could cause depletion. As it is beyond reasonable dispute that salmon
can be depleted by unrestricted exploitation, it is assumed that herring
can also be depleted by unrestricted fishing on pre-spawning popula-
tions. This assumption is the subject of critical scientific examination.
Of a dozen or so commercial species of groundfish the halibut is the
most important. It freezes well and is shipped frozen to the markets
of the continent. The fishery is principally by long-line in Hecate
Strait (between the Queen Charlotte Islands and the islands along the
mainland coast) and on the offshore banks of the continental shelf. It
is administered by an International Commisssion (Canada and the
United States) on the premise that at low or moderate levels of abun-
dance, increased fishing effort produces less fish. ‘The sable fish or black-
cod (Anoplopoma), so highly prized for smoking, is taken on the same
gear in deep water. The remaining groundfishes—flatfishes (Pleuwro-
nectidae), gray cod (Gadus macrocephalus), rock fishes (Sebastodes),
lingcod (Ophiodon elongatus)—yield excellent fillets for the fresh or
frozen trade on local or distant markets. They are taken principally by
trawls on banks of intermediate depth (15-100 fathoms) at times when
concentrations make for fast and hence profitable fishing.
The only truly oceanic fishery to attract Canadian fishermen is the
troll fishery for albacore. ‘The fish is canned as premium tuna for
Canadian consumption or exported frozen. Fishing may be as close as
six miles from shore but typically is offshore by 40 miles or considerably
more. The fishery is very erratic in occurrence and yield. ‘There is
in it an element of sport which appeals to many fishermen.
A small but effective shore-based whaling operation uses half a
dozen or more species of whales. The products (meal, solubles, oil, and
meat for fur farms) are sold on the world’s market. The promised re-
wards of the whaling industry are the only ones which have yet seemed
sufficient to justify deploying valuable capital equipment in organized
offshore projects. Canadian whalers work up to 150 miles off shore—
much farther than other company-operated vessels.
GEOGRAPHY AND METEOROLOGY OF THE AREA
The coast of British Columbia has many islands and inlets. Race
Rocks at the south end of Vancouver Island and Stewart at the north
end of the Portland Canal are less than 600 miles apart in a straight
line, but 16,900 miles of coast line intervene. The irregularities in the
shore line provide numerous good harbours where small craft can wait
out perilous weather or conditions which make fishing impossible. Al-
though there are many good harbours there are few or no permanent
316 EIGHTH PACIFIC SCIENCE CONGRESS
residents on them. The shore in many places is rough and inhospitable
and the surrounding terrain is so rugged as to make access by land dif-
ficult or non-existent. In consequence fishing communities are few and
widely separated and those with rail or road connections are even fewer.
Tidal change is moderate (12 to 26 feet maximum change at various
places). Tidal currents in the passages and inlets are, however, strong.
In a few places they make navigation hazardous and in others they are
too swift to be stemmed by small craft. They must be given thorough
consideration for efficient navigation on the coasts.
The prevailing winds are moderate to strong with occasional calms
and gales. Sudden high winds are not common. In deep water, seas
are seldom dangerous to properly loaded seaworthy vessels. However,
in the shallow waters of Hecate Strait or in situations where the wind
opposes strong tidal currents, steep waves develop which can be dan-
gerous to small craft.
"TECHNOLOGICAL POSITION
The fishing industry of Western Canada has made use of the tech-
nological knowledge of the Western Hemisphere. It has been applied
both to processing and to capture. The principal method of process-
ing is canning. ‘To it are applied the special techniques of machine
cleaning of fish; and of filling, capping, exhausting, sealing, and retort-
ing of cans.
The fish reduction industry uses presses and centrifuges especially
adapted to its purposes and special evaporators for concentrating solu-
bles in the press liquor. General plant construction and arrangement
take advantage of new power sources and engineering methods.
The installations for the frozen fish trade apply principles of refri-
geration engineering as developed by scientists of the Fisheries Research
Board. Similarly, the application of newly developed principles to
smoke house construction has improved control of the process to the
point where the operation is largely freed of dependence on uncon-
trolled conditions.
The greatest single contribution of technology to catching is the
development of compact, dependable, and economical power units to
propel vessels and to operate deck equipment. More recent develop-
ments of great general usefulness are the radio telephone which facil-
itates concentration of the fleet on large bodies of fish and with shore
headquarters or processing plants; and the echo sounder, which makes
navigation more certain, allows troll and trawl fishermen to follow the
contours of the bottom, and reveals the presence of deep schools of fish.
General developments of more recent application are radar, which
UTILIZATION OF CANADA’S PACIFIC MARINE RESOURCES 317
facilitates prompt return to harbours in fog or dark, and the range
finder and Loran for general assistance in offshore navigation.
The machines mentioned above were developed for other purposes
and later adapted to fishing vessels. “There are special developments,
too. Prominent are power driven drums on the sterns of small boats
for easily setting out and picking up gill nets (or handling long lines),
larger drums for handling salmon purse seines, power driven gurdies for
handling trolling lines, the older long line gurdies of the halibut boats,
and stabilizers for trollers and other smaller craft. These are the pro-
ducts of the ingenuity and enterprise of fishermen. Other ideas are
constantly being tested and rejected or modified. All increase the ef-
ficiency of fishing or reduce the physical labour of fishing and, in so
doing, shift the emphasis for success in fishing from physical strength
and hardihood to ingenuity and technical skill.
A_ variety of factors contributes to the rapid development of ef-
ficient fishing methods. ‘The army of fishermen is not a stable one: it
is always receiving recruits from (and losing deserters to) other indus-
tries—logging, farming, construction—so that new ideas, some practical,
some naive, are continually being tried, with the good ones being
adapted and applied to local conditions. Furthermore, Western Ca-
nadian fishermen are recruited from a variety of the great fishing centres
of the world so that methods successful in other places are available for
trial under local conditions. In general, there is ample opportunity to
try and apply new fishing methods within existing regulations. When
successful ones are developed, the educational standard is high enough
to facilitate the ready dissemination of information through trade and
technical journals. ‘The organization of the industry is at once strong
enough and adaptable enough to bring promptly into general use all
really useful developments.
ECONOMIC POSITION
The fishing industry of Western Canada is centred on a favoured
section of a favoured continent. The inhabitants of British Columbia
have no urgent need of fish as a protein food. Rather, they use the
choicer varieties occasionally as a change from meat. In general the
processed products of the fishing fleets are shipped to the markets of the
continent and the world to provide exchange for the foods and manu-
factured goods which go toward maintaining a high standard of material
welfare.
APPLICATION
The low local demand for untreated fish and the wages for labour
expected by fishermen require that most of the fish be processed in one
318 EIGHTH PACIFIC SCIENCE CONGRESS
way or another. In general this can be done most cheaply in the few
large centres of population having good transportation facilities. A
few specialized communities relying entirely on fishing products have
been located at places convenient to the fishing grounds. ‘Technological
advances are improving established processing methods and developing
new ones.
The Canadian fishing industry depends upon exports, and in con-
sequence is in an assured competitive position only in cases where there
are advantages in fish availability or in some other way. There is little
incentive to organize costly offshore operations (such as for tuna) in
competition with exploiters from other nations.
The vessels used must be large enough to deliver paying fares to
fishing ports or buying stations which are rarely as much as a day’s run
from the fishing grounds. They must be large enough to continue fish-
ing in moderate weather in order to complete paying loads, but they
need not ride out severe gales as safe harbours are always within reach
of the fishing grounds. ‘The boats must, of course, be large enough
to handle effectively the gear in use and to accommodate the necessary
fishing aids. ‘The tendency is accordingly toward the use of craft of
medium size. Boats used in the marine fisheries are customarily 35 to
85 feet long depending on the gear used and the places and seasons of
operation. Salmon gill net boats used in the inlets and river estuaries
are smaller and lighter in construction.
Because the economic situation puts the emphasis on financial re-
turn rather than on efficient use of the whole resource, the fish utilized
are those commanding the highest prices or those whose habits make
it convenient to capture them in very large numbers. Only such species
can produce sufficient return to allow the fishing profession to compete
successfully for the time of potential fishermen. However, for these
species more fishermen are attracted to the fishery than are necessary
to take all the fish which can safely be removed from the reproducing
stock.
As the most important fisheries in Western Canada are for ana-
dromous fishes which are liable to depletion by over-fishing, regulations
have been introduced to assure each year an adequate number of
spawners. These regulations limit fishing or define the gear. In general,
the resource has been fully used for years. Consequently, each tech-
nological advance in fishing efficiency must be matched by regulations
reducing the effectiveness of the gear. A paradoxical situation is pro-
duced but such seems inevitable in view of the biological facts and the
accepted policy not to refuse fishing privileges to any citizen.
UTILIZATION OF CANADA’S PACIFIC MARINE RESOURCES 319
Regulations prevent fishing much above tidal influence or, at
smaller streams, near the river mouths at all. Such regulations and the
fishermen’s desire fer comfort and efficiency have, during recent years,
promoted the use of gasoline-driven boats, replacing rowboats and sail-
boats. Still more recently competition for fish has led to the use of
larger and faster boats so that the fish can be met and caught as they
approach the meuths of the rivers. There results an economic balance
between the efficiency resulting from access to all of the fish as they
approach the fishing grounds and the inefficiency arising from using
better equipment than is necessary to do the work. The situation has
been encouraged by the increasing market price for fish. When prices
fall the point of economic balance may shift so that the use of expen-
sive equipment may become unprofitable. Adjustment is likely to prove
very awkward.
RESEARCH ATTITUDE
The fisheries resources of Western Canada are the subject of mod-
erately intense research. Research on the wholly marine species (except
herring) adapts traditional approaches to the local species and prevail-
ing conditions. As a basis for assuring maximum sustained utilization,
information is sought on such matters as migrations, population limits,
the factors controlling abundance through year-class variation, factors
influencing catchability by modifying shoaling habits, rates of growth,
and intensity of the fishery. ‘he objectives and approaches for herring
are complicated by the herring’s inshore spawning in the intertidal zone
and the consequent conviction that the species is subject to economic
extinction by overfishing. Full scale experiments to test the effective-
ness of protective regulations aré in progress.
Most research effort is devoted to salmon. ‘The anadromous habit
makes salmon extremely vulnerable to fishing. The determination and
provision of the number of spawners required to perpetuate the re-
source without withholding an unnecessary surplus from the fishery, are
major problems whose difficulty is increased by the variations in re-
productive success which occur from year to year under natural condi-
tions in the freshwater habitats of salmon. The parts played by droughts,
freshets and frost in suppressing salmon populations are under investiga-
tion. Such information is needed beth for the determination of the pro-
portion of the runs which should be used by the fishery and for the
prediction of variations in the abundance of available fish so that the
industry may avoid economic loss through unnecessary surplus of fish
on the spawning grounds.
320 EIGHTH PACIFIC SCIENCE CONGRESS
The special hazards which are faced by anadromous fish as a re-
suit of human activities have been mentioned previously. Perhaps the
most serious interference with natural conditions is produced by hydro-
electric developments which intrude impassable barriers to upriver sal-
mon, pass practically all of the water through their turbines, and create
great new lakes in their storage reservoirs. Much effort is being put on
studies of methods to guide upstream and downstream migrating sal-
10n past obstructions. Culturing in coastal lakes or special nursery
areas may prove necessary and the conditions controlling survival are
being studied with that in mind. As hydro-electric power is in increas-
ing demand, there is a great sense of urgency in the researches which
seek means for preventing the destruction of the salmon fisheries.
POISONOUS FISHES AND THEIR RELATIONSHIP TO MARINE
FOOD RESOURCES IN THE PACIFIC AREA *
By Bruce W. HALSTEAD
School of Tropical and Preventive Medicine
College of Medical Evangelists
Loma Linda, California, U.S.A.
INTRODUCTION
Recent declines in fish catches in certain regions in the Pacific have
stimulated scientific organizations to investigate ways and means of
developing latent fishery resources. Other fishing grounds are being
explored, and the addition of new fish species to the consumers’ menu
is being considered. The decline in catches becomes even more serious
when considered in the light of increasing human population through-
out the world. ‘This increase is estimated to be progressing at the rate
of 1 to 1.25 percent per annum, or in terms of numbers, about 25
million people a year. Unfortunately, the population increase has not
been matched by the production of food stuffs. Many of the southern
Asiatic countries, which prior to World War II were exporters of food
stuffs, have since become importers.
Increases in population, decreased food production resulting from
political and military upheaval, and the general decline in fish catches
have all contributed toward making protein food stuffs a subject of con-
cern. It is not unusual, therefore, that economists should focus their
attention on the almost untapped protein food reserves of the sea. How-
ever, the development of the shore fisheries of the tropical Pacific will
present important problems regarding the edibility of certain fish species
which fisheries and public health organizations must not ignore.
ECONOMIC SIGNIFICANCE OF POISONOUS FISHES
The economic significance of poisonous fishes can probably be more
readily appreciated by reviewing a few instances which have occurred in
the tropical Pacific within the last ten years. According to Mr. P. F.
D. Palmer,! who has managed the Fanning Island Plantations Limited
(Line Islands) and has been a resident of the island since 1936, poi-
* This investigation was supported by a research grant from the Division of Research
Grants and Fellowships of the National Institute of Health, Public Health Service, Bethesda,
Maryland, supported in part by the United States Air Force under contract No. AF 18(600)—
451, monitored by Research Secretariat, U.S.A.F., School of Aviation Medicine, Randolph Field,
Texas,
o21
322 EIGHTH PACIFIC SCIENCE CONGRESS
sonous fishes (exclusive of puffers) were unknown prior to World War
II. Fishes of all types were commonly eaten and supplied to the native
workers for their main source of protein. Between February 1946 and
April 1947 there were 95 cases of fish poisoning amongst the population
of 224 people on the island. A clinical account of these outbreaks has
been published by Ross.? Palmer further states that from 1946 to 1950
there were “hundreds” of cases of poisoning resulting from the very
same species of fishes which they had formerly eaten without ill effect.
The problem finally reached the point where feeding their native per-
sonnel became critical. Fortunately most of the pelagic species, mullet
and some of the lagoon fishes remained edible. Within the last year or
two the situation seems to be improving and some of the species have
been placed on the edible list again.
A report received from Dr. Vernon Brock, Director, Division of
Fish and Game, Board of Agriculture and Forestry of the Territory of
Hawai,’ indicated that more than 60 tons of red snapper (Lutjanus
spp.), ulua (Caranx spp.) and miscellaneous reef fishes were shipped
to the Honolulu fish markets during the years 1930 to 1937. During
this time not a single outbreak of fish poisoning was known to occur
as a result of eating these fishes. Since the year 1944 scores of outbreaks
have resulted from eating Line Island fishes. Some of these outbreaks
have been reported by Lee and Pang.‘
As a direct result of these epidemic unfavorable publicity has de-
veloped regarding Line Island fishes. Species such as red snapper (Lut-
janus gibbus, L. vaigiensis, L. bohar), manini (Acanthurus triostegus),
grouper (Epinephelus spp.), seabass (Variola loutt), ulua (Caranx
spp.) and others, are no longer permitted to be imported from the Line
Islands and sold in the Territory of Hawai. A situation such as this
results in both fishermen and consumers refusing to have anything to do
with fishes coming from a poisonous fish zone.
During the period September 1950 to July 1953, field studies were
conducted by our organization in the Phoenix, Line, Hawaiian, Maria-
nas, Eastern and Western Carolines, Johnston, Okinawa, Japan, Gala-
pagos, Cocos, La Plata Islands, the Gulf of California and Panama Bay.
Studies thus far indicate that the poisonous fish population of the trop-
ical Pacific is much larger than was formerly believed. ‘Toxic species
have been found to occur in the Pacific from the Galapagos Islands to
the Philippines and Okinawa, and from Midway to the Society Islands.
The survey at Canton demonstrated that about 27 percent of the reef
fishes were toxic. The survey at Johnston Island indicated that about
75 percent of the species tested were poisonous. Once an area has estab-
lished a reputation it is very difficult to change public opinion. As
POISONOUS FISHES 323
new fishing grounds are entered and the spectrum of food fishes
broadened, public acceptance will be one of the factors determining the
success of the venture. A few epidemics can have disastrous effects in a
struggling industry, resulting in enormous financial losses and wanton
waste of valuable fisheries resources. With the present trends in world
population and food supply we can ill afford waste of any food resource
and particularly those supplying protein.
RESULTS OF SURVEY STUDIES
The following report is based upon the field investigation pre-
viously mentioned. ‘Table I consists of a compilation of families of
fishes which have been incriminated in human intoxications, animal
feeding and inoculation tests. This tabulation was made from 574 case
histories and technical reports. Cases resulting from ordinary bacterial
food intoxications were not included. In addition, approximately an-
other five hundred reports were received that were concerned with more
general aspects of poisonous marine organisms.
Many persons have the erroneous idea that poisonous fishes are
restricted to “trash fishes’, those species which would be generally un-
acceptable as food for humans, but such is not the case. Perusal of
Table I will reveal that the phylogenetic spread is remarkably broad.
Families marked with an asterisk indicate those groups which are gen-
erally considered to be of commercial importance by various Pacific
peoples. Some of the families listed are fresh-water, European, Asiatic
or American, but the bulk are Pacific marine fishes. The list obviously
fails to consider a number of important factors, viz., geographical lo-
cality, ecological biotope, maturity of the fish, and season of the year.
Hence, because a family is listed in this table it does not mean that any
or all of the members of that family are poisonous throughout their
geographic range.
The problem of recognizing a poisonous plectognath is a relatively
simple one, since most of the members of this order adhere to a fairly
consistent morphological pattern. Numerous toxicological surveys and
case reports by Japanese, Australian and American scientists clearly in-
dicate that most plectognaths are to be regarded with suspicion until
proven otherwise.* However, the identification of poisonous non-plec-
tognath fishes presents some very real problems because of a number of
unique factors, viz.: (1) Apparently, under the proper environmental
*In Japan and many of the other Oriental nations poisonous puffers are routinely eaten
and considered a delicacy. The fishes are prepared in a special manner in order to remove
the poison and thus make them safe for human consumption. However, in spite of these pre-
cautions, the Japanese Government reports more than 125 deaths a year resulting from the
eating of these fishes. During the 1l-year period from 1927 to 1937 puffer poisoning accounted
for 44 percent of the total food poisonings in Japan and was listed as their greatest single
eause of fatal food intoxication.
324 EIGHTH PACIFIC SCIENCE CONGRESS
conditions, any fish-like vertebrate is capable of developing (concentrat-
ing or metabolizing—which?) ichthyosarcotoxins which can be lethal to
man. (2) Poisonous fishes are widely distributed throughout the torrid
zone, and some species are known to occur in temperate and arctic
waters. (3) A fish that is a valuable commercial species in one area
may be poisonous to humans in another locality. Hence, conclusions
derived from an epidemiological survey in one area may have little or
no bearing upon the incidence or identification of poisonous fishes else-
where. Distances of even a few miles may entirely alter the epidemiolog-
ical picture. (4) The problem is not a static one. Fish species which
were once edible and commercially valuable species have within the
last ten years become poisonous. The situation which has occurred at
Line, Johnston and Midway Islands may be cited as classical examples.
There are no valid statistical data whether the over-all incidence of fish
poisoning is probably on the increase. (5) There is no correlation be-
tween the incidence of toxicity and season of the year in most species.
Instances of intoxication commonly occur throughout every season of the
year. (6) There is no simple field test whereby a toxic fish can be dis-
tinguished from an edible one. A poisonous fish appears in form and
action no different than a non-toxic fish.
The question of why a fish becomes poisonous is a difficult one to
answer. Numerous theories have been propounded, but few of them
harmonize with the field observations. The reader is referred to the
works of Gudger,® Hiyama * and Halstead * for a more complete review
of these theories. ‘There is no single explanation that will satisfy the
entire picture.
Recent studies indicate that ichthyosarcotoxins evolve from a num-
ber of different sources and through the interplay of a variety of phy-
siological processes. Hence the term ‘ichthyosarcotoxism’ is an all-em-
bracing one in which are included a number of different and distinct
clinical entities. This is indicated by the symptomatology of humans
resulting, for example,* from the European barbel (Barbus barbus
[Linnaeus]), the Pacific puffer (Arothron hispidus [Linnaeus]), the
Greenland shark (Somniosus microcephalus [Bloch and Schneider]) ,
the bluefin tuna (Thunnus thynnus [Linnaeus]), the moray eel (Gym-
nothorax flavimarginatus [Ruppell]), and red snapper (Lutjanus vai-
giensis [Quoy and Gaimard]), are quite distinct. Nothing is known re-
garding the origin of the poisons found in fresh-water fishes, such as the
barbel, nor in sharks. The histamine-like poisons found in scombroid
fishes (tuna, bonito, mackerel, etc.) are believed to be tissue break-
down products, possibly the result of bacterial action. Such fishes as the
* The fishes listed are representative cf various groups of poisonous fishes which are capable
of producing different types of intoxications.
POISONOUS FISHES 3825
puffer, moray eel and red snapper are believed to become poisonous
because of their eating habits.
The acquisition of poisonous properties by a fish is thought to be
derived as a result of herbivorous fishes feeding on poisonous marine
algae. Carnivorous fishes would become poisonous by feeding on poi-
sonous herbivores. Controlled laboratory feeding studies have demon-
strated that at least one species, Leptocottus armatus Girard, the Cal-
ifornia staghorn sculpin, has the ability to feed on poisonous fish flesh
and harbor the poison in various tissues of its body with no apparent
alteration in its behavior. Studies are now in progress on this particular
phase of the program and will be reported at a later date. This food
chain theory has been presented in greater detail in our “Survey of the
poisonous fishes of the Phoenix Islands.” *
Ichthyosarcotoxism in man is frequently confused with various
types of bacterial food intoxications. True fish poisoning is in no way
related to putrefactive processes, hence the state of freshness of the fish
has no bearing on the production nor the potency of the poison.* ‘The
chemical nature of these poisons, exclusive of puffer poison, are un-
known. Some fish poisons appear to. exert a variety of physiological
effects which represent the combined action of the different compo-
nents. Many of the symptoms resemble those produced by such com-
pounds as aconitine, muscarine and curare. Many of the scombroid
(tuna-like) fishes produce rather violent histamine-like reactions, which
appear to be dependent on the freshness of the fish. On the other hand
some of the skipjacks contain neurotoxins which are frequently present
in freshly caught specimens.
Japanese scientists have studied tetraodon toxin or puffer toxin in
great detail. Tetraodon toxin has been assigned the provisiona! formula
of C,,H,,NO,,. It has been isolated as a white hygroscopic powder
soluble in water and insoluble in the ordinary organic solvents. It is
neither a protein, an alkaloid, nor a protamine. ‘The exact chemical
nature and relationship of other ichthyosarcotoxins have not been stu-
died to date. All fish poisons, however, are water soluble and relatively
heat stable. Ordinary cooking procedures do not destroy or appreciably
alter the potency of the poison.
CLINICAL CHARACTERISTICS
Since the Pacific Science Congress is primarily concerned with
Pacific research, the discussion of the clinical aspects of ichthyosarco-
toxism is limited to the four clinical types of ichthyosarcotoxism com-
monly recorded for the Pacific area.
* The only exception to this statement is in the case of scombroid poisoning which results
from eating inadequately preserved fishes. However, the symptoms are quite different from
ordinary. types of bacterial food poisoning.
326 EIGHTH PACIFIC SCIENCE CONGRESS
]. Tetraodon (Puffer) poisoning: The causative organism is a
puffer, one of the members of the suborder Tetraodontoidea. The
symptoms commonly noted are in time frequency numbness of the lips,
tongue, tips of fingers and toes, which usually develops within 30 minutes
after the ingestion of the toxin. This is followed by nausea, vomiting,
headache, dizziness and extreme weakness. Power of speech becomes
impaired and dyspnea is marked. Within two hours as a rule, the
patient suffers complete paralysis with muscles relaxed, body limp, and
inability to speak although conscious. Just prior to death the patient
lapses into unconsciousness. Death generally occurs in severe cases with-
in 1 to 24 hours as a result of respiratory paralysis. Mortality rate is
estimated to be about 60 per cent. Prognosis is considered to be good
if the patient survives the first 24 hours.
2. Gymnothorax (Moray eel) poisoning: ‘The causative source is
a member of the genus Gymnothorax. Symptoms of tingling and numb-
ness about the lips, tongue, hands and feet usually develop within 20
minutes to 7 or 8 hours after ingestion of the toxin. Nausea, vomiting,
laryngeal spasm, aphonia, excessive mucus production, foaming at the
mouth, injection of the conjunctiva, paralysis of the respiratory muscles,
motor incoordination, violent clonic and tonic convulsions, abnormal
deep and superficial reflexes and coma follow in rapid sequence. The
mortality rate is estimated to be about 10 per cent.
3. Ciguatera: Numerous species of marine fishes are capable of
causing this type of poisoning. Tingling followed by numbness usually
develops almost immediately or within a period of 30 hours after in-
gestion of the toxin. Nausea, vomiting, diarrhea and abdominal pain
are present in about 75 per cent of the cases. Joint aches, malaise, chills,
fever, prostration, headache, profuse sweating, pruritus, metallic taste,
generalized motor incoordination, muscular weakness, and myalgia are
common. Sensory disturbances are present in most cases, hot objects
are interpreted as feeling cold and cold objects as hot or like “electric
shock” in typical complaints. Convulsions and severe paralyses are less
common. ‘The mortality rate is comparatively low, estimated to be about
2 to 3 per cent, and recovery from severe intoxication is very slow, some-
times taking weeks or months to recover completely from the weakness
and myalgia.
4. Scombroid poisoning: Members of the genera Euthynnus and
Katsuwonus are common offenders. In rare instances these fishes may
produce symptoms typical of the ciguatera type of fish poisoning, but
more frequently the clinical characteristics are typical of a violent his-
tamin-like reaction. It is the only form of ichthyosarcotoxism known
in which inadequate preservation or freshness of the fish appears to be
POISONOUS FISHES 327
a factor in the production of the poison. The symptoms generally de-
velop within a few minutes after ingesting the fish and consist of nausea,
vomiting, redness and flushing of the face, engorgement of the soft tis-
sues of the eyes, swelling and cyanosis of the lips, tongue and gums,
giant urticaria, severe itching, headache and respiratory distress. ‘The
victim usually recovers within eight to twelve hours. ‘The few bacte-
riological analyses of the fish flesh for human pathogens have been nega-
tive. Moreover, the toxin appears to be water soluble and is not de-
stroyed by ordinary cooking procedures. The problem of scombroid
poisoning has been discussed in greater detail elsewhere.°
“TREATMENT
There is no known specific antidote at the present time. An at-
tack of fish poisoning does not impart immunity. ‘The treatment is
purely symptomatic. Gastric lavage and catharsis should be instituted
at the earliest possible time. Intravenous 10 per cent calcium gluconate
in many instances has given prompt relief while in others it has been
ineffective. Victims suffering from moray eel poisoning appear to be
particularly susceptible to violent convulsions and may present dif-
ficult nursing problems. Since the convulsions are precipitated by noise,
rest, quiet and sedation are essential. Paraldehyde and drop ether have
been reported to be the drugs of choice in controlling the convulsions.
Coramine or one of the other respiratory stimulants are advisable in
cases of respiratory depression. Excessive mucus production in the
buccal cavity is treated by aspiration and constant turning of the
patient. Atropine has been found to make the mucus more viscid and
difficult to aspirate, and is not recommended. If laryngeal spasm is
present, intubation and tracheotomy may be necessary. Nasal oxygen
and intravenous fluids supplemented with parenteral vitamins are usual-
ly beneficial. If the pain is severe, opiates will probably be required.
Morphine given in small divided doses has been recommended. Cool
showers have been found to be effective in relieving the severe itching.
Fluids given to patients suffering from the paradoxical sensory disturb-
ance should be warmed. Vitamin B complex supplements are advisable.
SUMMARY
he expansion of commercial fishing interests and the utilization
of various species of shore fishes in the tropical Pacific impose upon
fisheries and public health organizations an urgent solution to the prob-
lem of poisonous fishes. Poisonous fishes are widely distributed through-
out the torrid zone, but some species occur in temperate and arctic
waters. Poisonous fishes are distributed throughout the entire phylo-
O28 EIGHTH PACIFIC SCIENCE CONGRESS
genctic series of fish-like chordates, including cyclostones, elasmobranchs
and numerous groups of true fishes. Edible and commercially valuable
species in one locality may prove violently poisonous in another area.
The pharmacological and chemical properties of most ichthyosarco-
toxins are unknown. ‘The poisons are water soluble and are not de-
stroyed by ordinary cooking procedures. Bacteria are not involved in
the production of the poison. Ichthyosarcotoxism or fish poisoning ap-
pears in the form of different clinical entities. Four clinical types of
ichthyosarcotoxism typified by various neurological and gastrointestinal
symptoms are known to be endemic to the Pacific area: ‘Tetraodon, Gym-
nothorax, Ciguatera and Scombroid poisoning. ‘The interrelationship of
the various poisons involved is not understood. The treatment of fish
poisoning is largely symptomatic. Research is urgently needed on the
distribution, biology, ecology and systematics of reef fishes. “he prob-
lem of poisonous fishes and fish poisoning will become of increasing
economic and public health importance in the Pacific area in the years
to come.
ACKNOWLEDGMENT
The author takes pleasure in acknowledging the many helpful sug-
gestions and kindly constructive criticism received from Dr. K. F. Meyer
in the preparation of this manuscript.
LITERATURE CITED
1. PALMER, F. D. Personal communication. April 11, 1958.
2. Ross, S. G. Preliminary report on fish poisoning at Fanning Island. (Cen-
tral Pacific). Med. Jour. Australia, 2 (21): 617-621, (Nov. 22) 1947.
3. Brock, V. Personal correspondence. June 10, 1953.
4, Leg, R. K. and H. Q. PANG. Ichthyotoxism—fish poisoning. Amer. Jour.
Trop. Med., 25 (8): 281-285, 1945.
5. GUDGER, E. W. Poisonous fishes and fish poisonings, with special reference
to Ciguatera in the West Indies. Amer. Jour. Trop. Med., 10 (1):
43-55, (Jan.) 1980.
6. Hiyama, Y. Poisonous fishes of the South Seas. U.S. Fish and Wildlife
Serv., Spec. Sci. Rep., Fish. 25: 1-188, 1950.
7. HALSTEAD, B. W. Ichthyotoxism—a neglected medical problem. Med. Arts
and Sew., 5 (4): 1-7, 1951.
Some general considerations of the problem of poisonous fishes
and ichthyosarcotoxism. Copeia, (1): 31-38, 1953.
8. HALSTEAD, B. W. and N. C. BUNKER. A survey of the poisonous fishes of
the Phoenix Islands. Copeia (in press).
9. HALSTEAD, B. W. A note regarding the toxicity of the fishes of the genus
Euthynnus, the black skipjacks. Calif. Fish and Game (in press).
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SOME ASPECTS OF FISHERIES PROBLEMS IN THE
SOUTH PACIFIC AREA
By A. H. J. Kroon
Economic Development, South Pacific Commission
Noumea, New Caledonia
Fish plays an important role in the life of most inhabitants of the
South Pacific area. It is their main source of protein. The Fisheries
Conference held in 1952 at Noumea under the auspices of the South
Pacific Commission stressed the importance of fish in the diet and
pointed out that as land animal protein is not a regular item in the
diet of the peoples of the region and as in most territories, social and
economic factors limit the possibility of an early or rapid expansion
of protein food supplies from livestock, fish is the most accessible and
also the cheapest source of animal protein.
In Melanesia, the present consumption of fish is on a lower scale
than in Micronesia and Polynesia, where the consumption of fish and
other marine products (algae, molluscs and crustacea) seems rather
high, though accurate data are not yet available.
A part of the population of the region, and even a great part, are
not in a position to obtain fish easily. I am mainly thinking here of the
impression that there are great untapped resources available. It is felt
of the other islands fish production is often insufficient to cover the
needs of the population, chiefly due to seasonal influences.
The enormous acreage of the South Pacific Ocean leads to the
impression that there are great untapped resources availabie. It is felt
that the Pacific Ocean is a region where enormous quantities of valuable
food are produced, and that we have to do with the problem of the
“untaken crop.” One may ask if the untaken crop problems such as
those in the field of fisheries, sago production, timber production and
so on, are not somewhat over-emphasized in modern times. The un-
taken crops in the world can only contribute to economic development
in as far as the harvesting is within economic possibilities.
Though there are still vast acreages of forests in the world, their
exploitation is often impracticable for economic reasons. ‘There are a
number of rubber producing plants in nature, but their harvesting is
not practical, as it is cheaper to leave those resources “‘unharvested”’
and to grow hevea rubber.
331
Bon EIGHTH PACIFIC SCIENCE CONGRESS
Mankind has nearly always passed from the stage of collection, of
harvesting what was available in nature, to the stage of cultivation;
from collecting and hunting to growing and raising.
In fisheries we see the same picture, on the one hand fish catching,
the harvesting of what is available in nature, and on the other hand
fish culture, or controlled production.
The abundance of fish in the Pacific Ocean and the fact that the
largest ocean in the world furnishes food for only a few million people
could lead to the idea that there is no need of fish culture in addition
to fish catching. But reality seems to point in a different direction. It
is a strange fact that the fish production in the South Pacific area is not
sufficient to meet the needs of the population. Instead of being a fish
exporting region the Pacific islands are importing fish. New Guinea’s ©
imports of fish and fish products in 1952 amounted to a quantity of
more than 1,744,000 Ibs. with a value of nearly fAust.186,000; the
figures for Fiji are 1,748,000 lbs. with a value of £¥F.154,500; Western
Samoa 1,280,000 lbs. with the value of £NZ.46,230; American Samoa
405,000 Ibs. having a value of $47,380. Other territories such as Papua,
Tonga, New Hebrides, New Caledonia, French Oceania, Gilbert and
Ellice Islands Colony and Netherlands New Guinea also have an ap-
preciable import of fish. Although complete figures of fish imports are
not available, a rough estimate gives a value of £400,000 Sterling per
year for the region. The available figures indicate furthermore that
imports are increasing. ‘Thus it seems possible that fish production in
the region has not kept pace with the increasing population. It was
stated at the Fisheries Conference that coastal populations sometimes
abandon fishing and prefer to buy their food, even including fish in tins.
Especially the deep-sea fishing (for pelagic fishes) seems to be declining.
The report of the Fisheries Conference refers to:
“A declining interest among the local populations in the
conduct of fishing operations at market-fisheries level and some-
times even at subsistence level.”
FisH RESOURCES
The resources within the region can be divided into:
(a) marine fisheries;
(b) inland fisheries.
The marine fisheries are generally divided into:
(a) coral reef and lagoon resources;
(b) mangrove and estuarine resources; and
(c) oceanic resources.
FISHERIES PROBLEMS IN THE SOUTH PACIFIC AREA BO)
The inland fisheries can be divided into:
(a) fish catching in rivers, lakes, swamps and fresh water
estuaries;
(b) fish culture in ponds.
Reef fishing is the main source of fisn supply. The limited reef
area of some islands and the fact that fish stocks on the reefs are isolated
within their particular reef systems set a limit to the yield. The Fisheries
Conference states:
“In some localities, in the neighbourhood of concentration of
regional population, these resources appear to have been over-ex-
ploited and the current harvest is small. These instances include
reefs in the neighbourhood of Rarotonga (Cook Islands), Pago
Pago (American Samoa), Papeete (Tahiti), Suva (Fiji), and
Noumea (New Caledonia) .”
The rapid rate of population increase in Polynesia and Micronesia
and the deficiency of the diet in the interior of New Guinea make the
problem of how to allow for higher levels of fish consumption per head,
even more acute. Under such conditions it seems not unlikely that this
reef and lagoon source, already over-exploited in some areas, will be-
come more and more deficient in relation to the increasing demands
of the future.
The mangrove and estuarine resources are believed to be abundant
and relatively unexploited in New Guinea. ‘The Conference report
states:
“It is in mangrove and estuarine areas that the greatest poten-
tial for pond culture exists, but in New Guinea and large islands
in Oceania the relatively large tracts of land might be expected,
with appropriate social and economic change in the lives of the
people, to make a contribution of animal protein on a scale which
obviously could not be reached by the smaller islands of the
region.”
Oceanic resources: ‘The development of pelagic fisheries in the
open ocean outside the reefs offers the best opportunity for increased
fish production, not only for markets within the territories but also
for export. ‘There are, however, in this field many unsolved problems
due to lack of knowledge of the pattern and distribution of the prin-
cipal species in these waters. Stocks in abundance sufficient to carry
commercial operations have been indicated in equatorial waters north of
New Guinea and south of the Caroline Islands. The Fisheries Con-
ference expressed the opinion that most prominent among these re-
304 EIGHTH PACIFIC SCIENCE CONGRESS
sources are the tunas, but there are numerous other species of potential
commercial value, such as flying fish, half beaks and mackerels.
The fisheries industry on a commercial basis should go together
with a more differentiated community where a group of fishermen
could earn their livelihood by catching fish for sale. Such differentiation
does not exist to any marked degree. ‘The number of fishermen in the
region who earn their livelihood by fish catching, although not known,
is very small. Development in that direction requires better processing
techniques.
PROCESSING
The Conference stated:
“The only methods of processing employed in the region are
salting, smoking and drying, mostly by crude and primitive tech-
niques. Only small proportions of fish caught are processed.”
In the papers submitted to the Fisheries Gonference some valuable
information on fish processing is supplied. ‘The paper submitted by
the Australian Delegation based on a survey of native methods of fish
preservation in New Guinea carried out by Mr. K. W. Anderson of the
Food and Transport Division, C.S.I.R.O., during April, May and June,
1950, states that the objects of that survey were:
“I. To evaluate methods at present in use;
2. To determine what improved methods might be introduced
to increase the storage life of the fish and make it available:
(a) for smoothing out seasonal fluctuations in supply
(b) for distributing to inland protein deficient com-
munities.”
In summarizing their observations, they state:
“As far as could be ascertained, the sole method for preserva-
tion of fish used throughout the territory was a simple, crude dry-
ing over a hot fire.”
The paper gives full information as follows:—
“The extent to which the fish is dried varies somewhat with-
in uncontrolled limits, but can broadly be classified into two
groups:—
(a) short term, partial drying, with or without prior cleaning of
the fish, giving a product that is relatively soft, probably has
moisture content in the range of 40 to 60% and a storage life
of one to seven days. ‘This is the technique used in the great
portion of the territory.
FISHERIES PROBLEMS IN THE SOUTH PACIFIC AREA 335
(b) a more complete drying of cleaned and split large fish or whole
uncleaned small fish, down to a moisture content of about 20%
where it is hard and dark in colour, but, when protected from
attack by insects, probably has an indefinite storage life even
under tropical conditions. This latter technique seems con-
fined to the Sepik River area.”
The same paper states that:—
“It is clear that in the absence of controllable pond fisheries
the preservation of coastal fish as a means of smoothing out seasonal
fluctuations in supply and of distributing inland to protein de-
ficient communities with a poor system of communication will
initially best be done by the traditional process of salting, drying
and smoking in suitable combination, rather than by adopting
elaborate processes such as freezing, canning and controlled
smoking.”
The importance of salt in the improvement of the existing primitive
processing techniques was emphasized by the Australian Delegation,
who stated that this salt will either have to be imported from Australia
or produced by setting up a plant for its recovery from sea water within
the territory itself.
Lack of cheap salt and a small market for preserved fish are partly
responsible for slow development in Netherlands New Guinea.
Controllable pond fisheries as a means of smoothing out seasonal
fluctuations in supply has already been mentioned. The culture of fish
in ponds is not unknown to the Polynesian and ponds seem even to
belong to the Indonesian-Polynesian cultural sphere. Fish cultivated
are the milk fish (Tuamoto Archipelago, Nauru Island, the Gilbert
Islands, the Lau Group), whilst the carp (Cyprinus carpis L.) was in-
troduced into Fiji fifteen years ago. ‘The Fiji Government initiated
pond culture experimentally in 1950 and yields of fish reached 1200 Ibs.
per acre per year. However, since sewage had been run into the ponds
to promote growth of algae, the Fijians would not eat the fish. In
other territories also there is a growing interest in pond culture. It is
unknown to what extent fish culture in ponds would contribute to a
higher fish production in the region and to a smoothing out of seasonal
influences. ae ae
The lack of information and data on Pacific island fisheries in
general was plainly shown and expressed in the papers submitted to the
Fisheries Conference. One of the recommendations of the Conference
Was:
336 EIGHTH PACIFIC SCIENCE CONGRESS
“That periodical and regular compilation and assessment of
quantitative and qualitative information on the fishing industries
be recognized as essential prerequisites to regional development.”
It is still not quite clear what course a short term development in
the field of fisheries should take. The necessary basic survey and assess-
ment of the fisheries resources and potentialities of the region is still
most essential and urgent.
At its Twelfth Session the South Pacific Commission authorized the
appointment of a Fisheries expert for a term of three years, to assist
and stimulate fisheries investigation and development in the region, in-
cluding inland fisheries and pond culture. It is hoped that these ac-
tivities will contribute to an absolute increase in production and to in-
creased production per head, permitting an improvement of the nutri-
tional value of the islanders’ diet.
November 19, 1953
SYMPOSIUM ON MARINE PROVINCES IN THE INDO-PACIFIC
REGION
(SPONSORED BY UNESCO)
Convener: Mr. A. W. B. Powext, Auckland Institute and Museum,
Auckland, New Zealand.
Secretary: Mr. INoceNcio A. RoNQUILLO, Bureau of Fisheries, Manila.
AWARDEES OF THE UNESCO SUBVENTION
Name Address Nationality
1. BRUUN, ANTON Fr. Deputy Keeper Danish
University Zoological Museum
Copenhagen K—Denmark
2. CHU, TSU-YAO Meteorologist, in charge of Re- Chinese
search Section
Taiwan Weather Bureau
64 Kong Yuen Road
Taipei, Taiwan, China
3. CLEMENS, WILBERT A. Director Canadian
Institutes of Oceanography
and Fisheries
University of British Columbia
Vancouver, Canada
4, HARDENBERG, J. D. F. Head, Laboratory for Investi- Dutch
gation of the Sea
Passar Ykan, Djakarta
Indonesia
5. HipaKa, Kosi Professor Japanese
Geophysical Institute
Tokyo University
Tokyo, Japan
6. PANIKK4R, N. KesAvA Chief, Central Marine Indian
Fisheries Research Station
Mandapam Camp, South India
7. POWELL, A. W. B. Assistant Director New Zealander
Auckland Institute & Museum
P. O. Box 9027, Newmarket
Auckland, S. E. 1.
New Zealand
8. SERENE, RAOUL R. Director, Institut French
Oceanographique
Nhatrang, Viet-Nam
337
308 EIGHTH PACIFIC SCIENCE CONGRESS
9. SERVENTY, D. L. Senior Research Officer Australian
Wildlife Survey Section
C.S.1.R.O., Arundale Hall
1 Museum St., Perth
Western Australia
10. THOMPSON, THOMAS G. Professor of Oceanography American
University of Washington
Seattle 5, Washington
UC S.A.
PROCEEDINGS
The Symposium was sponsored by UNESCO, organized and con-
vened by Mr. Powell, the Assistant Director of the Auckland Institute
and Museum, Auckland, New Zealand. It was alloted one whole day
for presentation. ‘There was a large attendance drawn from Zoology,
Geology and Botany as well as Oceanography. ‘The rather full pro-
gramme of fiiteen papers was accommodated by mimeographing all pa-
pers in full and distributing copies the day before the meeting. ‘his
avoided tedious full length reading of contributions and allowed ade-
quate time for discussion after each paper and a reasonable amount of
time at the end of the session for general consideration of the topic.
The symposium convened at 9:00 A.M. with Mr. Powell opening
the convention by speaking briefly on the manner in which the sym-
posium was to be conducted, the number of minutes to be alloted to
each paper, and the scope of the discussions.
The papers were grouped into three categories, namely deep sea,
distribution for general areas, and distribution for particular areas.
The subjects represented by the fifteen papers embraced algae, plankton,
holothurians, bryozoa, mollusca, fishes, and birds.
The first paper read. was that of Dr. W. A. Gosline, Hawaii,
entitled “The Nature and Evolution of the Hawaiian Inshore Fish
Fauna.” The paper dealt with the Hawaiian provinces and inshore
fisheries in the upper 200 meters of water. He endorsed the Schilders’
Hawaiian Province, into which he advocated including Midway and
Line Islands. The geography, water temperature, and current systems
of the Hawaiian Chain in relation to the evolution and endemism of
Hawaiian fishes were discussed.
Mr. Powell’s paper, “Marine Provinces of the Indo-West Pacific,”
outlined the several published propositions for subdividing the area.
It was suggested that the 18 named provinces for the Indo-West Pacific
advocated by F. A. and M. Schilder (1939) were in excess of practical
requirements. It was also suggested that this nomenclature applied
mainly to shallow water faunas and that consideration of both deep
PROCEEDINGS 339
sea and pelagic faunas would probably require separate consideration.
Both these points were affirmed by other contributions and endorsed
by several speakers. “Iwo slides and a full page map were presented.
A question in methodology was brought up but it was suggested that
it be taken up in the afternoon discussions.
The next paper, “An Outline of the Distribution of Pacific Deep-
Sea Animals”, was presented by Dr. Anton Fr. Bruun, Denmark. It
covered the deep areas at and below 2,000 meters and described the
Pacific Abyssal and abysso-pelagic fauna as part of a cosmopolitan deep
sea fauna. The suggested subdivisions of the deep sea faunas were
(1) Pacific and (2) Atlantic-Indian Ocean from which an Antarctic
region may be separable. Slides showing specimens of deep-sea species
accompanied the presentation of the paper.
Dr. Rolf L. Bolin, California, on “Deep-Water Biological Provinces
of the Indo-Pacific’, based his classification on the Archibenthic fish
family, Macrouridae, which occur within a 200—2,000 meter range. It
discussed myctophids and bathymetric fishes as indicators of biological
provinces in the Indo-Pacific. Dr. Bolin’s suggested provinces were
fewer, of larger scope, and were obviously not delimited by the same
factors that gave rise to the shallow-water provinces. ‘The author spe-
culated on the existence of other marine biological provinces as indi-
cated by fishes and other marine fauna, but suggested more compre-
hensive and detailed investigations before drawing conclusions. ‘There
was agreement, however, in the recognition of a Hawaiian Province.
Professor Martin W. Johnson of Scripps Institution of Oceanography,
in “Some Outlines of Piankton Concentration in the Eastern and Tro-
pical Pacific’, dealt with surveys involving marine plankton distribution
along this west coast of North America and in some parts of the tropical
Pacific. “The surveys were made by different scientific institutions in
connection with the California Cooperative Sardine Research Program.
The discussion related to the constitution of the plankton found in
western Indonesia and also that found near the California coast. Dis-
cussion follows:
Dr. HARDENBERG: May I ask whether you can tell us about the com-
position of the plankton?
Dr. JoHNson: ‘They are mostly edible diatoms, Rhizosolenia, and are
substantially not dinolagellates or watery planktons as Salpa.
Dr. HARDENBERG: In Western Indonesia, there are few diatoms in the
plankton. They are mostly Peridinium and watery organisms.
Dr. JoHNSON: We need more work on plankton. We should give em-
phasis to knowing what we are working on.
340 EIGHTH PACIFIC SCIENCE CONGRESS
Dr. HarpENBERG: It is hard to study our plankton due to the great
abundance of floating water organisms.
Dr. Jounson: The plankton is not worked out seasonally. It is not
such in watery plankton. However, near the California Coast, in
spring, there is a large volume of plankton.
Drs. Yaichiro Okada and Shizuo Mawatari of Japan, in their paper
entitled “Distributional Provinces of Marine Bryozoa in the Indo-Pa-
cific Region”, presented a preliminary report on the distribution of the
Indo-Pacific bryozoa, tracing geographical isolation and the oceano-
graphical factors responsible for the formation of Bryozoan Provinces
in the Indo-Pacific region. They recognize three subregions, the In-
dian, the Western Pacific and the Central and Eastern Pacific with eight
provinces: (1) Ethiopian and (2) Indian for the Indian Subregion,
(3) Malayan, (4) Chinese and (5) Papuan for the Western Pacific
Subregion, and (6) Hawaiian, (7) Polynesian and (8) Mexican for
the Central and Eastern Pacific Subregion. Discussion follows:
Mr. Domantay: In your study of Japanese Bryozoans have you come
across species of Bowersbankia?
Dr. Oxapa: Yes, there are four species found in Japan but these are
not mentioned in this paper.
“The Distribution of Polychaetes within the Indo-Pacific Region”
by Mr. G. A. Knox of the Canterbury University College, New Zealand,
is the first distributional survey of this group for the area. ‘The poly-
chaetes inhabiting the shelves of 24 regions in the Indo-Pacific area
were dealt with. Description of the species in the text was supple-
mented by tables on the distribution and number of species found in
each of the 24 regions. Extensive tables are given, an analysis of which
points to recognition of the following faunal areas:—(1) Indian, with
possibly a separate Arabian Sea region, (2) Malayan, (3) Philippine,
including South China Sea, (4) Southern Japanese, (5) Northern Jap-
anese, (6) Hawaiian, (7) Tropical Pacific. This paper was read by
Mr. Powell.
Dr. Leonard P. Schultz in his paper, “A New Approach to the Dis-
tribution of Fishes in the Indo-West-Pacific Area” presented a grouping
of. marine ecological habitats. It advanced the concept that the so-
called species as named by Zoogeographers are actually composed of two
or more species, subspecies or races, each more or less inhabiting sub-
faunal areas. He considered that too much reliance has been placed
upon check lists prepared by ichthyologists with only a local faunal
concept and that the nomenclature used often stressed greater differ-
ences between faunas actually occurs zoologically. He advocates com-
PROCEEDINGS = a41
prehensive revisional work on generic, specific, and subspecific levels.
The discussion related to the spawning periods of marine organisms
in different areas. It was stated to be all the year round with certain
species in tropical Djakarta, March the month for most prevalent spawn-
ing of fishes at Palmyra and March, April and May for the Marshall
Islands. Comments and discussion follow:
Dr. HarvenBerc: In tropical Djakarta, most species spawn the whole
year round. We found two types that breed the whole year round
and another type that spawns during the fall and spring only. Are
your Carangids more or less related to our species?
Dr. ScHULTz: Yes.
Dr. Gostine: I found that the check list and list of species of fishes
of Guam could not be used in the case of the Hawaiian fishes. I
aiso found that the Hawaiian Islands are not coralline, that coral
reefs there are very small, with almost no atoll present, and that
those parts with cooler waters have different fishes.
Dr. ScHuLTz: You just have to ignore the list of fishes of Guam. Only
50% of it is correct. In one case, 35 species were listed as new
but the listing were later found not valid, and this is probably true
of other species. In the Samarano, if the ichthyologist cannot de-
scribe these, he classifies them as new, as was found in the case of
parrot fishes.
Dr. HALSTEAD: I made various studies of coral atolls at various times
of the year. In Palmyra I found that March is very definitely the
month when the fishes are most active as far as reproduction is
concerned.
Dr. Jonson: In the Marshall Islands, March, April and May show
very heavy spawning in plankton samples. It is probably so in
other places.
After the discussion on Dr. Schultz’s paper, Mr. Powell announced
a recess for refreshments.
The after-recess session began at 11:30. Only one paper, “The
Zoogeographical Distribution of the Indo-Pacific Littoral Holothurio-
idea”, by Mr. Jose S. Domantay of the Philippine Bureau of Fisheries,
was read. The paper covered the study of the littoral forms of Holo-
thurioidea found at depths not exceeding 50 fathoms. It proposed the
zoogeographical division of the Indo-Pacific Ocean based on the Holo-
thurian fauna, into the following ten provinces: (1) North Pacific
(2) South Pacific (3) East Pacific (4) West Pacific (5) Northwest
Pacific (6) Southwest Pacific (7) Northeast Pacific (8) Southeast Pa-
cific (9) Central Pacific and (10) Indian Ocean. ‘These areas for the
342 EIGHTH PACIFIC SCIENCE CONGRESS
most part fall readily into the named scheme of the Schilder’s. He also
advanced opinions on the causes for the unequal distribution of the
North and South Pacific Holothurian fauna. The number of the dif-
ferent species of the various provinces were tabulated and presented in
graphs and charts.
The session adjourned for lunch at about midday.
When the afternoon session resumed at 2:00 P.M. Mr. Powell an-
nounced that there were six more papers to be presented. He said that
aside from the discussion after each paper, there would be a general
discussion after all the papers had been read. Comments and sugges-
tions would be entertained. Mr. Powell then called upon Dr. Har-
denberg to read his paper.
Dr. Hardenberg’s paper entitled ‘Distribution of Marine Fishes in
South East Asian Waters” presented the general range of distribution
of tropical marine fish fauna of South East Asian seas. The complex
pattern of the occurrence of fishes in different regions was discussed.
It mentioned the division of the seas into regions, and the factors im-
portant to the ecology of the marine fauna. Various species were cited
for particular fish fauna of several regions with common ecological
characteristics.
The discussion was mostly concerned with the location of the eggs
and post-larval stages of parrot fishes.
Dr. Scuuttz: I have been troubled for years about parrot fishes and
how their eggs look like. Have you seen some eggs of these fishes?
Dr. HarpvENBERG: No. I saw only ovaries with small eggs. I have seen
a parrot fish in the open sea.
Dr. ScHuttz: We are troubled as to the identity of pelagic eggs at
Bikini Atoll. They looked like anchovies but these fish are not
found there. We even found certain fish eggs that looked like an-
chovy eggs.
Dr. Jounson: I found fish eggs 20 miles from the nearest land.
Dr. Scuuttz: What is the smallest parrot fish you have found?
Dr. HARvENBERG: ‘The smallest fish I have found is about 20 mm.
long. I observed the same condition in Caesio. ‘The smallest I
have seen is about 5 to 6 cm. long. I have seen Caesio spawn at
the edge of coral reefs and the larvae get away after spawning.
Dr. D. L. Serventy in “An Analysis of the Pelagic Bird Faunas of the
Indo-Pacific Oceans”, working on taxonomy in relation to distribution
patterns, considered that the whole of the Indian Ocean and the west-
ern and central part of the Pacific represented one homogeneous fauna
consisting of long-established descendants of the ‘Tethyan fauna of the
PROCEEDINGS 343
Tertiary. He did, however, recognize a sub-speciation centre in the
region of the Kermadec Islands. It interpreted the known taxonomic
and zoo-geographical facts. Factors regulating the ebb and flow of
species movement were analyzed. Faunal elements in the Indo-Pacific
region were presented with enumeration of bird species with their
habitat and migration. The paper was illustrated with three maps.
Dr. Murphy referred to this paper as an admirable review in which the
author reached a series of conclusions in harmony with the known geo-
logical history and without resource to hypothetical land gaps or land
bridges. Discussion follows:
Dr. Mvurpuy: Dr. Serventy’s study is more admirable than that review
it indicates. He found the breeding grounds of the sea bird spe-
cies not familiar to the audience. He built up a series of conclu-
sions which then coincides and harmonizes with the groups of sea
birds and the geological history. He needed no land gaps and land
bridges.
Mr. Tuss: I would like to ask about the flying habits of the frigate
birds. I have observed those that circle up to the point of invi-
sibility and, when very high, cross the country where they roost.
Boobies are also seen from land when nesting. ‘They fly direct to
waters near the nest.
Dr. SrrvENTy: Iam glad to know that frigate birds cross land and that
they fly far from roosting islands. I have not seen this in the lite-
rature.
Dr. HARDENBERG: I wish to confirm the statement of Mr. Tubb con-
cerning the flying habits of the frigate birds.
Dr. WoostER: When we were opposite Cape Monticino, a bird stayed
on our ship for three hours when we were about 1,500 miles from
land. I would like to know if petrels form colonies.
Dr. SERVENTy: ‘There are big scale conditions where petrels form co-
lonies, that is, from South America to California. There in a ran-
dom collection of birds we could recognize the New Zealand birds,
and other sea birds were presented. ‘There is no evidence, how-
ever, of migration of sea birds in historic times.
Dr. E. Yale Dawson’s paper, “Some Distribution Patterns Repre-
sented by the Marine Algae of Nhatrang Bay, Vietnam”, was read by
Dr. Maxwell S. Doty. It presented a brief picture of the present knowl-
edge of the marine algal flora of Indo-China. Results of the algal
study undertaken by the author on the distribution of the different
species and their occurrence were presented. ‘The paper also presented
two generalities on marine algae of the Indo-Pacific; namely, the out-
standing deficiency of information about algae not only of the South
344 EIGHTH PACIFIC SCIENCE CONGRESS
China Sea but also of the whole Indo-Pacific region, and local varia-
tions in ecology as the cause for the extreme diversity between algal
associations of adjoining localities.
‘The paper, “Some Problems on Marine Biogeographical Micro-
Provinces Surrounding Japan”, by Tadasige Habe, Tokubei Kuroda,
and Denzaburo Miyadi was read by Dr. Okada. It points out that in
southern Japan cold water continental coastal faunal elements often
survive in bays whereas the adjacent open coast may have a warm wa-
ter fauna belonging to a different marine province. Stress was made
on the idea that biogeography based on taxonomic differences is only
one side of biogeography. A comparison of bay fauna with littoral
fauna of the open sea, with specific examples of various species, was
presented. Several authors interpreted the term biogeographic prov-
inces in the ecological or zonation issue and this led to some discussion.
The characteristic aspects of marine littoral fauna which bear on bio-
geographical segmentation of Japanese seas were discussed.
The paper of R. K. Dell of the Dominion Museum, New Zea-
land, entitled ‘““The Marine Mollusca of the Kermadec Islands in Rela-
tion to Molluscan Faunas in the South West Pacific’, came next and
was read by Dr. Hiatt. It reviewed briefly the literature on the marine
mollusca of the region and the author’s own findings in his investiga-
tions of the different species and genera.
“The Geographical Variation of Early Embryonic Processes in Ma-
rine Eggs” was read by Dr. Alexander Wolsky, Principal Scientific Of-
ficer of Unesco in South East Asia. It dealt with the different factors
affecting the development of marine eggs, and the causes of geographic
variation in the embryonic processes. Dr. Boschma commented on the
paper.
Dr. BoscuMa: I agree with Dr. Wolsky that some species of animals
found in the North Sea and in the Mediterranean have differences
in their development. ‘The study of their embryos must be inte-
resting.
After this paper had been read, Mr. Powell opened the meeting
for general discussions.
Dr. Bruun: We found some Actinians in the Philippine Deep and also
in the Java ‘Trench. I believe that this form is endemic in the
trenches. We also found more in the depth of 6,000 meters, which
cannot differ much from those found in the deep waters of India
and Japan. As shown by the work of Dr. ZoBell, the bacteria for
the Philippine Trench die when subjected to a pressure of 800
atmospheres, while they live at a pressure of 1200 atmospheres. It
PROCEEDINGS 345
is possible that the deep sea fauna can be split according to dif-
ferences in pressure, i.e. variation in pressure at the slopes rather
than differences in temperature.
. GostinE: I found that the fishes in the high island are similar to
those found in the coral reefs and in the low islands. However,
I found that in high islands with low water temperatures the spe-
cies of fishes are poorer.
. ScHULTz: I have noticed the relationship of fishes in the different
provinces. As the distance gets farther for wide ranging species,
there is a considerable difference in morphology and color distinc-
tions. In different fish populations the colors vary widely. For
example with reference to eels the use of the color for differentia-
tion is very difficult to apply in the field.
. PANIKKAR: It is interesting that prawn is marine in the Mediter-
ranean but is estuarine in India and fresh water in China and
Japan. ‘They belong to the same species but differ physiologically.
Another example is Arenicola, which was recently found in the
Gulf of Bombay.
. Hratr: I hope that we are not confusing here ecological conditions
and biological distribution. We may find new arrivals of animals
in certain localities but we should not discuss these animals im-
ported by men, i.e., those that had not existed in that locality
before.
. Harry: I observed that the faunas in the Atoll area are different
from those in Hawaii, i.e., where the land shelf drops fast, and that
similar atolls have similar fishes.
. Borin: Rough shore and sandy beaches are different. Differences
in habitat in a biological province are not so important but the
similarities of fauna in high island and coral atoll are important.
. PowELL: ‘This symposium stimulates more interest along the line
of biogeographic distribution. Gentlemen, we have to conclude
this part of the session. When I say this part of the session, I am
referring only to the official presentation on the subject today, for
I am sure sufficient materials have been presented today to be the
subject of wide and lengthy discussions for a long time to come,
and I am very thankful indeed to all of you for your splendid
response to this symposium which I had the great pleasure of or-
ganizing. ‘Thank you very much.
The symposium adjourned at 4:30 in the afternoon.
: amen
met Hany tee
i ae ; ert ise ia }
THE NATURE AND EVOLUTION OF THE HAWAIIAN
INSHORE FISH FAUNA!
By Witii1AM A. GOSLINE
University of Hawaii
Honotute 1. Ls H., U.S. A:
INTRODUCTION
A very large number of the shallow-water animals of the Hawaiian
Islands are endemic, and the area is usually considered a major zoo-
geographic subdivision of the great, marine, shallow-water, Indo-West-
Pacific region (Ekman, 1953). Among Hawaiian species of inshore
fishes estimates of endemism range between approximately 15% (Fowl-
er, 1928) and 50% (Jordan and Evermann, 1905). In my opinion
the latter figure is about correct. Neither the distinctiveness of the
Hawaiian inshore fish fauna nor its derivation from an Indo-West-
Pacific stock are in doubt, and these matters will not be discussed here.
‘The purpose of this paper is to present a preliminary analysis of the
factors that appear to have brought about the present. status of the
Hawaiian shore-fish fauna. It is based on five years of investigation
and on collecting trips to Johnston, Wake, and most of the Hawaiian
Islands. Nevertheless, present knowledge is insufficient to provide more
than leads to the subject, and no help is to be obtained from other
components of the Hawaiian shore fauna, for they are more poorly
known than the fishes. Consequently the ideas presented here can de-
serve no rating higher than that of working hypotheses.
GEOGRAPHY
The Hawaiian Islands (Fig. 1) form a long, narrow chain extend-
ing for some 1600 miles along a southeast to northwest axis. Hawaii,
at the southern end of the chain is the largest island in the central
Pacific, whereas Kure, at the opposite end, is the northernmost coral atoll
in the Pacific. he greatest distance between any two islands in the
chain is less than 200 miles. For zoogeographic purposes, Johnston
Island (Fig. 1), about 450 miles to the south of the central part of
the chain, must be considered an outlying component of the Hawaiian
faunal area.
The nearest shallow waters to the north and east are those of the
Aleutians and Alaska, somewhat less than 2000 miles away. Between
1 Contribution No. 49, Hawaii Marine Laboratory in cooperation with the Department of
Zoology and Entomology, University of Hawaii.
347
348 EIGHTH PACIFIC SCIENCE CONGRESS
Hawaii and the mainland United States lie about 2000 miles of deep
water. There are no shallow-water fishes common to the Hawaiian
Islands and the shores of North America, though a few high seas
species, e.g., the albacore, inhabit both regions. ‘To the south of the
United States, America slopes away from Hawaii, so that the distance
from Hawaii to Panama is about 4000 miles. ‘Thus the nearest American
coasts with water temperatures similar to those of Hawaii are separated
from that island by at least 2500 miles of deep sea. ‘The Hawaiian fish
fauna has derived little or nothing from tropical American waters.
The nearest shallow-water areas to the Hawaiian chain lie to the
south and west. The Line Islands (Fig. 1) south of Honolulu extend
to within about 850 miles of Hawaii and to 800 miles southeast of
Johnston. Due west of Hawaii, Wake (Fig. 1), a northern outlier of
the Marshalls, lies about 1200 miles southwest of Midway (and about
half way between Honolulu and Japan).
WaTER TEMPERATURES
With regard to surface-water temperatures, it can be seen from
Table I that all of the islands of the Hawaiian chain, Wake, Johnston,
and Palmyra (in the northern Line Islands) have about the same tem-
peratures in summer; there is, however, considerable difference between
the northern parts of the Hawaiian chain and the other islands men-
tioned in winter. Since the Hawaiian fish fauna is essentially a tropical
one, it would seem probable that if any temperatures are critical for
Hawaiian fishes, they are those of winter. Consequently summer tem-
peratures will be dismissed from further consideration. In winter, the
differences in water temperatures within the Hawaiian chain are greater
than those between Hawaii and the northern Line Islands or Wake.
TABLE I
SURFACE WATER TEMPERATURE (FROM SVERDRUP, JOHNSON, AND FLEMING,
Cuarts II Anp III)
FEBRUARY AUGUST
TEMP. C. DIFFEREN CB TEMP. Cc. 4 DIFFERENCE
Wake 25 aI ean 28
i da 2
Midway 18 26
6 0
Hawaii 24 26
1 1
Johnston 25 oT,
| aL 0
Palmyra ez it |
NATURE AND EVOLUTION—HAWAIIAN INSHORE FISH FAUNA 349
If cold water were the principal limiting factor in the differentiation
of Hawaiian shore fishes, then greater variation would be expected
within the Hawaiian chain than between the northern Line Islands
or Wake and Hawaii. ‘This, however, dces not occur. On the contrary,
the fish fauna throughout the Hawaiian chain seems to be quite homo-
geneous. Except for slight indications of racial differentiation in two
species (Kuhlia sandvicensis and Istiblennius zebra), attempts to dis-
tinguish even races of fishes within the Hawaiian chain have been un-
successful.
As to number of species, there are several a priori reasons for sus-
pecting that it might differ at the two ends of the Hawaiian chain.
One is the great differentiation in winter water temperatures within
the chain noted above. A second is that the southeastern islands are
high and volcanic, whereas the northwestern are low coral atolls. Pre-
sumably all the atoll habitats are present around the high islands; how-
ever, the volcanic rock habitats of the eastern islands are absent from
the whole western part of the chain. Finally, there is the possibility
that the low western islands have a larger fauna because they are older.
Unfortunately, it is impossible to say whether the number of species
at the two ends of the Hawaiian chain actually does differ, for the low
leeward islands have been very poorly collected and the absence of
species records from these islands means nothing. Consequently, it be-
comes necessary to fall back on general impressions for what they are
worth. After collecting at most of the islands from Hawaii to Midway
it is my personal feeling that there is a decrease, though probably not
an evenly graded one, in the number of species from southeast to north-
west. Indeed I have collected no species in the leeward islands that
I had not already collected in the high Hawaiian islands. (On the other
hand the number of individuals of a species seems to increase from
south to north. Also, judging from a few non-commercial species, the
maximum size of individuals within at least some species increases from
south to north.) If, however, there are species on the high islands
restricted to lava rock habitats, I do not know them. In Oahu, the great
majority, at least, of the species found over lava rock may also be en-
countered over coral or coralline limestone areas. It seems necessary
then to fall back on winter temperatures as the cause of the decrease
in number of species in the leeward group, if indeed such a decrease
really takes place.
CURRENT SYSTEMS
The adults of most Hawaiian inshore fishes are bottom feeders that
would presumably starve in the open sea. It is generally believed,
350 EIGHTH PACIFIC SCIENCE CONGRESS
though by no means verified, that most such fishes arrived in Hawaii
as planktonic larvae carried in by the ocean currents. Under such pos:
tulates the current systems should play a dominant role in the develop:
ment of the Hawaiian inshore fish fauna.
However, there seems to be little correlation between the present
current systems of the Hawaiian region and the fish immigration routes.
Although the Hawaiian inshore fish fauna has come in from the south
and west, there are no known northeasterly-flowing currents reaching
the Hawaiian Islands (see Sverdrup, Johnson, and Fleming, 1942, Chart
VII). The North Equatorial Current, in which Hawaii lies, flows to-
ward the west, and the eastwardly flowing Equatorial Counter Current
does not pass within 800 miles of these islands. If the derivation of
the Hawaiian inshore fishes is to be tied in with present current sys-
tems there would seem to be only two possibilities, both in my opinion
rather remote. One is that the larval forms were carried to the east
of Hawaii in the Counter Current and then doubled back in a great
eddy of the North Equatorial Current that carried them over 800 miles
north. ‘The other is that Hawaiian fishes were carried in to Kure and
Midway from the Bonins and Japan by a southern tongue of the Ku-
roshio Current (see Sverdrup, Johnson, and Fleming, 1942: 122). This
would involve transport in a slowly moving current across more than
2000 miles of deep water.
There is of course the possibility that the current systems of the
Hawaiian area were different in the Pleistocene than they are today.
However, Arrhenius (1952) has shown that there was little or no dis-
placement of, at least, the Equatorial Counter Current during the Pleis-
tocene.
If the immigration of Hawaiian fishes took place randomly, e.g.,
via occasional eddies within the major current systems, then it would
seem logical that they came in from the nearest islands, namely, John-
ston and Wake. ‘There is indeed considerable evidence in the Johnston
fish fauna that this island has formed something of a way point in both
the immigration and emigration of Hawaiian fishes.
NATURE OF THE HAWAIIAN FisH FAUNA
Before treating the endemism among Hawaiian fishes it seems ad-
visable to divide these into several ecological categories. First, there
are a small number of Hawaiian fishes, mostly gobies, that have taken
up a primarily fresh-water existence in the streams of the high islands.
At the other end of the scale are the deep-water fishes, both bathy-
pelagic and bottom dwelling forms. ‘Third, there is a group in which
the adults are pelagic, e.g., most sharks, the tunas, flying-fishes, and
NATURE AND EVOLUTION—HAWAIIAN INSHORE FISH FAUNA 351
Schindleria. All three of the above-mentioned groups will be omitted
from further consideration in this paper. ‘The remaining, inshore fishes
will again be divided into two categories for purposes of treatment here.
One group contains those species ordinarily living in depths of ap-
proximately 200 to 600 feet, and the other those fishes usually inhabit-
ing depths of less than about 200 feet.
OF those fishes living between 200 and 600 feet, relatively little is
known. In Hawaii there is a considerable hand-line fishery for such
species, but only the larger forms are taken, and of these only the edible
forms are brought in. About all that can be said of this group is that
it seems to show less endemism and a greater affinity to the Japanese
fish fauna than is present among shallower-water forms.
The rest of this paper will be devoted to those fishes usually living
in less than 200 feet of water. “This inshore group is not only the best
known, but contains well over half of all the fishes recorded from the
Hawaiian Islands. Four main features must be noted about these forms.
First, a large proportion of the Hawaiian species appear to be endemic.
Second, at most a very few of the Hawaiian genera are endemic. ‘Third,
the Hawaiian inshore fish fauna, in distinct contrast to the Hawaiian
terrestrial biota, is a harmonic (balanced) one. Finally, the Hawaiian
fish fauna does not appear to be a particularly impoverished one by
Central Pacific standards.
It is necessary to discuss each of the above points in some detail.
Since the lack of endemic genera and higher categories is most easily
dismissed, it will be dealt with first. ‘There are, to my knowledge, only
two genera of Hawaiian shallow-water fishes (Gregoryina and Micro-
brotula) that can be considered endemic. However, both of these are
made up of small, rarely collected forms that may have been overlooked
elsewhere.
The statement that a large proportion of Hawaiian inshore species
of fishes are endemic needs some qualification, for the question may be
raised whether the Hawaiian endemics are not merely subspecies. In-
deed it cannot be proved that these endemics will not and do not in-
terbreed with their central Pacific counterparts (see below). Never-
theless, there are two basic reasons for considering the Hawaiian en-
demics as full species. One is that the Hawaiian representatives of an
Indo-Pacific Artenkreis are usually better differentiated than any other
populations of the Artenkreis, e.g., Acanthurus sandvicensis in the A.
triostegus complex (Schultz and Woods, 1948). ‘The other and more
important reason is that no intergradation can be demonstrated at the
borders of the ranges between the Hawaiian and the central Pacific
forms. Johnston and Wake (Fig. 1) are both islands which geograph-
352 EIGHTH PACIFIC SCIENCE CONGRESS
ically lie somewhat between the Hawaiian and central Pacific faunal
areas, and a mixture of these two faunas (but with a high predom-
inance of Hawaiian forms) is found at Johnston. Nevertheless, no
intergradation between the Hawaiian endemics and their central Pacific
counterparts was found at Johnston. Among four species complexes
investigated in some detail (Muraenichthys cookei- laticaudata, Gymno-
thorax eurostus-buroensis, Acanthurus sandvicensis-triostegus and Kuhlia
sandvicensis), the Johnston populations of the first three represented
the pure Hawaiian stock, and of the fourth the pure central Pacific
form. In no instance were both the Hawaiian and the central Pacific
forms found at Johnston, nor have they been found together elsewhere.
As to the harmonic nature of the Hawaiian fish fauna, a very high
proportion of the families and genera of shore fishes found in the central
Pacific east of Samoa have representatives in Hawaii. ‘There are, how-
ever, two notable and curious gaps in the Hawaiian shallow-water fish
fauna. Throughout most of the tropical Pacific, two of the most prom-
inent genera are Lutjanus and Epinephelus. In the northernmost of the
Line Islands, for example, perhaps a half dozen species of each of these
genera occur. In the Hawaiian Islands and Johnston Lutjanus appears
to be totally unrepresented, and Epinephelus occurs only in a single,
deep-water form. Yet the families to which these two genera belong are
abundantly represented in Hawaii by other, smaller, deeper-water genera.
These gaps seem especially peculiar in that both genera are made up
of generalized, moderate to large sized fishes. Furthermore, both are
present in Japanese waters that would seem to be colder than those of
Hawaii.
With regard to the relative size of the Hawaiian fish fauna, little
can definitely be said. On the one hand numerous central Pacific species
are unrepresented in Hawaii. On the other, more inshore species are
recorded from Hawaii than from any one central Pacific island group
east of Samoa. However, except for Hawaii, no central Pacific island
group east of Samoa has been adequately collected. Under any circum-
stances the Hawaiian inshore fish fauna, with some 400-500 known
species, cannot be called depauperate.
CHARACTERISTICS OF HAWAIIAN ENDEMIC FISHES
The characteristics by which Hawaiian endemic fishes differ from
their ancestral forms, i.e., their central Pacific representatives, can best
be treated under two categories: physiological and morphological. In
morphological features the Hawaiian endemic fishes show no pattern
of divergence from their central Pacific relatives. One Hawaiian en-
demic has a greater number of fin rays; a second has fewer gill rakers;
a third has the dorsal fin originating farther forward; a fourth has
NATURE AND EVOLUTION—HAWAIIAN INSHORE FISH FAUNA 358.
slightly longer jaws; a number differ in various details of color pattern;
etc. Even within a family no trend of divergence is shown by the various
Hawaiian endemic members. Consequently there seems to be no pos-
sibility of correlating the morphological peculiarities of Hawaiian en-
demics with distinctive features of the Hawaiian environment, e.g.,.
colder water temperatures. One anticipated correlation of this sort is
strikingly absent: Hawaiian coral reefs are notably dull colored as
compared with those of the central Pacific, yet the fishes seem to be as.
brightly pigmented as those to the south. It is not, therefore, easy to
escape the inference that the morphological peculiarities of Hawaiian
endemic fishes are per se non-adaptive.
‘Treatment of physiological differentiation is handicapped by the
fact that almost nothing is known of the physiological reactions of
tropical marine fishes. It might be expected that Hawaiian fishes have:
become physiologically adjusted to life in colder waters than their more
tropical ancestors. ‘There is some indirect evidence for, and none against,.
this supposition. The best available bit of information in this connec-
tion is derived from the spawning seasons of certain Hawaiian fishes.
One would expect (Ekman, 1953: 113) that a tropical species living
in Hawaii would spawn, at least primarily, during the summer months
when water temperatures most closely approximate those of its an-
cestral home. However, many Hawaiian fishes spawn primarily or en-
tirely in winter at temperatures below those ever reached in more trop-
ical regions. One example will suffice. Around Honolulu Pomacentrus.
jenkinst spawns from December to March; no ripe females have been
taken during the remaining months. At Arno, 10° nearer the equator
in the Marshalls, Dr. Strasburg informs me that ripe females of this.
same species were taken in July. (Hawaiian specimens of Pomacentrus
jenkinst do not seem to be morphologically distinguishable from their
central Pacific counterparts, which further emphasizes the advisability
of treating the morphological and physiological peculiarities of Ha--
walian forms separately.)
The restriction of spawning in Pomacentrus jenkinst (and other
similar examples can be given) to winter around Oahu is the reverse:
of what would be expected, and the explanation for this phenomenon
is obscure. Perhaps the Hawaiian populations of P. jenkinst have at
one time become adapted to waters even colder than exist around.
Oaliu today, e.g., in the Pleistocene, and the winter spawning is merely
a holdover from such adaptation. (In any event, the Hawaiian fishes.
must either have come in since the Pleistocene, under which supposi-
tion it is difficult to explain the high degree of endemism, or they must.
have been able to survive the Pleistocene water temperatures of Hawaii.),
354 EIGHTH PACIFIC SCIENCE CONGRESS
CAUSES OF ENDEMISM AMONG HAWAIIAN FISHES
In the preceding sections the nature of the Hawaiian fish fauna
has been discussed. It remains, however, to attempt some explanation
to the question of why it is as it is. Why, on the one hand, has not
the fish fauna undergone the adaptive radiation found in the Hawaiian
terrestrial fauna (see Zimmerman, 1948)? Why, on the other hand,
is there any endemism among Hawaiian fishes at all?
The answer to these questions would seem to be found in the
degree of isolation of the Hawaiian Islands. “Though the Hawaiian
chain is equally isolated in space for both fishes and terrestrial organ-
isms, the fishes (and other marine organisms) seem far better adapted
to getting there than most terrestrial forms. ‘This is immediately in-
dicated by the balanced nature of the fish fauna as compared with the
terrestrial biota. Indeed there are a large number of central Pacific
fishes unrepresented in Hawaii, but on the whole it looks more as though
such absences were due to unsuitable conditions for survival rather
than to inability to arrive there.
If the foregoing is correct, most or all suitable inshore environ-
mental niches have been filled by immigration, and the possibility of
an adaptive radiation among Hawaiian fishes is precluded. But also,
if the foregoing is correct, the question of why there is any endemism
at all among Hawaiian fishes becomes difficult to answer.
In my opinion, the endemism among Hawaiian fishes has been
brought about by two factors acting together and, in general, additively.
The primary cause is a moderate degree of isolation. ‘The secondary
cause is the slightly colder water of the Hawaiian Islands as compared
with the tropical central Pacific.
With regard to isolation, it has been stated above that the vast
majority of central Pacific fishes have probably arrived in Hawaii at one
time or another. By this it was not meant that the Hawaiian fish po-
pulation is deluged by an influx of immigrants every year, but rather
that one or a small number of specimens of most central Pacific species
have managed to get to the Hawaiian chain from time to time. Pre-
sumably the original entrants, if they survived and reproduced, would
have had time to saturate the islands with their descendants before the
next immigrants arrived. ‘There is some evidence that such a process
does take place. As already noted, at Johnston the pure central Pacific
stock of Kuhlia sandvicensis is represented, but among three other
fishes the pure Hawaiian form is present. Apparently what has occurred
is that in the case of Kuhlia the central Pacific stock has been able to
saturate the island with its representatives. Subsequent immigrants
from Hawaii were either unable to survive at Johnston, or if they
NATURE AND EVOLUTION—HAWAIIAN INSHORE FISH FAUNA 355
survived and interbred with the central Pacific form they did so in such
relatively small numbers as to leave no trace of intergradation on the
Johnston population. For the other three fishes the situation would
seem to be similar except that the Hawaiian form has either arrived
first or totally displaced the central Pacific type.
The original immigrants to Hawaii that gave rise to the descend-
ant population may or may not have been aberrant members of the
ancestral stock. Furthermore, during at least the initial increase in the
population, random drift may have been effective. Finally, among
Hawaiian fishes, these possibilities of aberrant initial immigrants and
random drift may have occurred at least twice, once at the stepping
stone of Johnston (or possibly Wake) and again on first arriving in
Hawaii.
The above factors (more fully treated in Zimmerman, 1948: 122-
125) may have caused differentiation through isolation per se, and this
differentiation would be of a non-adaptive type. Once arrived in the
Hawaiian Islands the fishes may have undergone further differentia-
tion in adapting themselves to the colder waters of this area. (Evidence
for one such adaptation has already been discussed.) Such adaptive
physiological differentiation would increase the ability of the residents
to compete with further immigrants, so that these would be able to
pass even fewer genes into the resident population than before (provid-
ing of course that they could interbreed at all). Consequently, I believe
that the integrity of a Hawaiian endemic species has been maintained
whether or not an occasional central Pacific immigrant has interbred
with it, and that the physiological adaptations of the endemics have
insured them from extermination through competition with the central
Pacific immigrants that may have arrived subsequently.
REFERENCES
ARRHENIUS, G. 1952. Sediment cores from the East Pacific. Reports of the
Swedish Deep-Sea Expedition 1947-1948, vol. 5, fase. 1, pp. 1-227.
EKMAN, S. 1953. Zoogeography of the sea. Sidgwick and Jackson Limited,
London: 417 pp.
FowLer, H. W. 1928. The fishes of Oceania. Memoirs of the Bernice P.
Bishop Museum, vol. 10, pp. 1-540.
JORDAN, D. S. and B. W. EVERMANN. 1905. The aquatic resources of the
Hawaiian Islands. Part I. The shore fishes. Bulletin of the U.S. Fish
Commission for 1903, vol. 28, pt. 1, pp. 1-574.
SCHULTZ, L. P., and L. P. Woops. 1948. Acanthurus triostegus marquesensis,
a new subspecies of surgeonfish, family Acanthuridae, with notes on re-
lated forms. Journal of the Washington Academy of Sciences, vol. 38,
pp. 248-251.
356 EIGHTH PACIFIC SCIENCE CONGRESS
SVERDRUP, H. U., M. W. JOHNSON, and R. H. FLEMING. 1946. The oceans.
Prentice-Hall, Inc., New York: pp. 1-1087.
ZIMMERMAN, E. C. 1948. Insects of Hawaii. Volume 1. Introduction.
University of Hawaii Press, Honolulu: pp. 1-206.
ODT
NATURE AND EVOLUTION—HAWAIIAN INSHORE FISH FAUNA
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MARINE PROVINCES OF THE INDO-WEST PACIFIC
By A. W. B. POWELL
Auckland Institute and Museum, New Zealand
The precise definition of shallow-water provinces in the tropical
Indian and Pacific Oceans is difficult since accurate faunal lists are few,
not many bibliographies have been published, and the systematics of
only a few groups are adequately known.
The purpose of this paper is not to present a scheme based upon the
systematics and biogeographic data of one phylum (mollusca) but to
invite discussion of the topic by workers representative of as many phyla
as possible.
If a working plan satisfactory to the majority of interests emerges
from this discussion it is hoped that agreement may be reached regard-
ing both the nomenclature and the respective boundaries of any ap-
proved provinces.
It is realized that provinces apparent in the littoral do not neces-
sarily extend to the deep waters, not even to the continental shelf in all
instances. The abyssal faunas probably bear no relation to the shallow-
water faunas and will require separate consideration. Pelagic faunas
also will probably require special treatment.
The recent appearance of Ekman’s “Zoogeography of the Sea’
(1953) will undoubtedly cause a renewed interest in biographic studies.
Ekman’s classification of the tropical faunas is as follows:
1. Indo-West Pacific. Indian ocean to 30-35°S and the western
part of the Pacific between 35-40°N and 30-35°S; extending from
the east coast of Africa to the Hawaiian, Marquesas and Tua-
motu Islands.
2. Atlanto-East Pacific.
A. Tropical and Subtropical America
a. Pacific American warm water region.
b. Atlantic American warm water region.
B. Tropical and Subtropical West Africa.
We are concerned only with the Indo-West Pacific which Ekman
subdivided into—
]. Indo-Malayan, 2. Islands of the Central Pacific (excluding Ha-
wall), 3. Hawaii, 4. Subtropical Japan, 5. Tropical and Subtropical
Australia, and 6. Indian Ocean.
359
360 EIGHTH PACIFIC SCIENCE CONGRESS
Recognition of the Indo-West Pacific as a homogeneous faunal
region is irrefutable. To this region alone is confined all the Recent
sea snakes. Of the 46 Recent species of the coral Fungia only one is
found outside the region. Among living molluscs Nautilus, Hippopus,
Tridacna and Malleus are not found elsewhere. Without mentioning
specific instances Ekman (1953) refers to many coral and alcyonarian
families confined to the Indo-West Pacific, and Myers (1940) recognises
many families and genera of fishes not found outside this region.
The outstanding paleogeographic condition that gave rise to this
vast faunal region was undoubtedly Suess’ Tethys Sea which allowed
almost unimpeded dispersal in the tropical zone. This sea is known
to have persisted with but brief local interruptions from the Lower
Cambrian to the Tertiary.
The recognition of the influence of this vast waterway readily dis-
solves many otherwise anomalous cases of discontinuous distribution.
In molluscs, for instance, the spread to the Austro-Neozelanic provinces
in the Tertiary of characteristic Paris and Vienna Basin genera (Eocene-
Miocene), such as Baryspira and later Pecten and Ranella, is note-
worthy.
Although the segregation of faunas within the Indo-West Pacific
must be of late development a fairly clear segregation is even now ap-
parent with endemism strongly marked in areas of continental origin
as opposed to the oceanic faunas of islands of coral or recent volcanic
origin.
A false impression of uniformity in the molluscan faunas of the
widely scattered insular areas of the Indian and Pacific oceans is given
by the extensive distributional patterns of common species of spectacular
appearance; i.e. the spotted cowrie Cypraea tigris, and the spider-shell
Lambis lambis.
In many unrelated tropical gastropod families two efficient free-
swimming larval types, known respectively as Sinusigerid and agadinid,
are characteristic of most of the Indo-West Pacific wide ranging species.
It is therefore among the sedentary and less conspicuous elements
that endemism is apparent and in the mollusca in particular many
-regional species and subspecies are apparent.
Ekman’s six divisions of the Indo-West Pacific are in my opinion
conservative, and on the other hand the eighteen divisions advocated
by F. A. Schilder and M. Schilder (1939) on the basis of a world survey
of the Molluscan family Cypraeidae are certainly excessive. Ekman
made no reference to this work in his “Zoogeography of the Sea.”
The Schilders advocated the division of the Indo-West Pacific into
three ‘“‘provinces”’ and eighteen “regions”. ‘Their terminology should be
reversed of course, i.e. “province” = subregion, and “region” = province.
MARINE PROVINCES OF THE INDO-WEST PACIFIC 361
The scheme is as follows:—
A. INDIAN PROVINCE.
]. Erythraean Region. Red Sea.
2. Persian Region. Persian Gulf to Karachi.
3. African Region. Somaliland to Mozambique and Southern
Madagascar.
4. Lemurian Region. Northern Madagascar, Reunion, Mauri-
tius, Seychelles and Maldive Islands.
5. Indian Region. India and Ceylon.
B. CENTRAL INDO-PACIFIC PROVINCE.
6. Sumatran Region. Andaman and Nicobar Islands, Sumatra,
Christmas Island, Sunda Strait and south coast of Java.
7. Moluccan Region. Bali Strait to Timor, Aru Islands, West-
ern New Guinea and Moluccas.
8. Java Sea Region. Southern Celebes, S.E. Borneo, North Java,
Malaya and Gulf of Siam.
9. Sulu Sea Region. Annam, Northern Borneo, Northern Ce-
lebes and Philippines.
10. Japanese Region. S.E. China, Formosa and Southern Japan.
11. Dampierian Region., N.W. Australia and Western Australia
north of Sharks Bay.
C. PACIFIC PROVINCE.
12. Queensland Region. New South Wales to Port Curtis Queens-
land, Lord Howe Island and Norfolk Island.
13. Melanesian Region. Northern and Eastern New Guinea, Bis-
mark Archipelago, Solomon Islands, Torres Straits Islands,
New Hebrides, Loyalty Islands and New Caledonia.
14. Samoan Region. Kermadec Islands, Fiji, ‘Tonga, Niue and
Samoa.
15. Oceanic Region. Gilbert and Ellis Islands, Vokelau and
Marshall Islands.
16. Micronesian Region. Caroline Islands, Palau Islands, Guam,
Marianas and Bonin Islands.
17. Polynesian Region. Cook Islands, Society Islands, ‘Tuamotus,
Marquesas Islands and Easter Island.
18. Hawaiian Region. Hawaiian Islands and Midway Island.
Practically every worker will disagree in detail with the Schilders’
scheme which in places suggests convenience rather than the expression
of natural biogeographic areas. Nevertheless the scheme provides a
useful framework upon which either to build or to dismantle.
362 EIGHTH PACIFIC SCIENCE CONGRESS
Perhaps because I know my own region best I find most fault with
the East Australian-South West Pacific section of the scheme. For in-
stance, No. 12, the “Queensland Region” has been subdivided to the
satisfaction of Austro-Neozelanic workers on the basis of systematic
studies in mollusca, echinoderma and aigae, with a recent endorsement
from the ecologists (Bennett & Pope, 1953).
There is general recognition of the Peronian warm-temperate prov-
ince for New South Wales and the Solanderian tropical province for
Queensland to Cape York. It may be noted, however, that Whitley
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A NEW APPROACH TO THE DISTRIBUTION OF FISHES
IN THE INDO-WEST PACIFIC AREA
By LEONARD P. SCHULTZ
Smithsonian Institution
United States National Museum, Washington 25, D.C., U.S.A.
Much has been written on the distribution of marine fishes of the
Indian and Pacific Oceans. Roughly ichthyologists classify the marine
ecological habits into three categories, shore, pelagic, and deep-sea. Al-
though these groupings are useful there is a considerable overlap be-
tween the zones and their limits vary in different seas.
Shore fishes are those that occur over the continental shelf or along
the coastal areas, and around the shores of islands; as adults, normally
not far out to sea, and usually in depths shallower than 600 feet. Most
typical deep-sea fishes live in the stratified subsurface layers of the sea
and because of the uniformity of temperature and salinity in these
areas, they may have an almost world-wide distribution.
The marine shore fishes may be divided into two main regions:
tropical and temperate. ‘The tropical shore fauna extends around the
world but is definitely restricted by temperature. ‘The temperate fauna
may be subdivided into: North Pacific, North Atlantic and Temperate
South Pacific.
The circumtropical marine shore fauna may be divided into two
main regions: Indo-West-Pacific and West-Atlantic-East Pacific.
The richest marine shore fauna of the world is that of the tropical
Indo-West-Pacific containing, with but few exceptions, representatives
of all known living tropical shallow-water marine fish families and a
very high percentage of all the genera occurring in other tropical
regions.
The geographical boundaries of the tropical Indo-West-Pacific
shore fauna are in general the region from the head of the Red Sea
southward along the African coast to Natal, thence eastward including
island groups and coastal regions of Southern Asia, northward to the
Ryukyu Islands and Southern Japan, southward to Northern Australia,
the Great Barrier Reef and New Caledonia, thence eastward to the Tua-
motu Islands and Easter Island, northwestward to include the Hawaiian
Islands. Although the boundaries of this region are ill-defined the fauna
is mostly restricted to coral reefs.
413
414 EIGHTH PACIFIC SCIENCE CONGRESS
The tropical West-Atlantic-East Pacific shore fauna in the Pacific
extends from the Gulf of California and Lower California southward
to Ecuador and the very northern part of Peru, including the adjoining
offshore Clipperton, Cocos, and Galapagos Islands.
Statements that the tropical East-Pacific shore fauna is trenchantly
distinct from the Indo-West Pacific are only partly correct. It is true
that the West-Atlantic-East Pacific has a very high percentage of distinct
endemic species, but there is a substantial percentage of species very
closely related, some the same, others of the subspecies level, common
to both regions—on the generic level there is a high percentage of genera
and subgenera common to both regions. ‘This condition of closer re-
lationship is more pronounced in some families than in others, and in
a few families the close relationships are lacking. ‘They are closer in
the Clipperton and Cocos Islands than along the Pacific American shores.
The statements by Zoogeographers as summarized by Ekman (Zoo-
geography of the Sea, pp. 15-16, 1953) on the great distinctness of this
eastern Pacific fish fauna has been based to some extent on misinforma-
tion. This has resulted from studies by ichthyologists who have con-
fined their observations to limited faunal areas, resulting in conclusions
based on local faunistic concepts. There has never been published a
single paper comparing the genera or species common to these major
faunal areas. "Too many systematic ichthyologists are individualistic
and have created numerous generic and specific names based only on
difterences for the fishes of their local faunas. ‘The result therefore
is to magnify differences by means of different names on the generic
and specific level whether important structural differences do or do not
exist. Zoogeographers base their differences between faunal areas to a
large extent on the percentage of different generic and specific names
occurring in faunal check-lists. Too many of these check-lists are pre-
pared by ichthyologists who know only their local faunas, and have
never had an opportunity to study widely ranging species and genera.
This lack of comparison of the wide-ranging species in wide-ranging
genera, and of genera in wide-ranging families, tends to cause zooge-
cgraphers to establish barriers that exist to some extent in scientific
names only.
For example, conclusions have been made on the basis of the 1928
“Check-list of North and Central American Fishes” by Jordan, Ever-
mann and Clark. Ichthyologists are nearly unanimous in their opinion
that the check-list elevated hundreds of subgenera to generic level and
numerous genera to sub-family level. Thus when this check-list is com-
pared with others of a still more local faunal concept the number of
“distinct genera” by name is greatly multiplied.
NEW APPROACH TO THE DISTRIBUTION OF FISHES 415
Since there are practically no careful comparisons of the wide-rang-
ing species and genera common to these major faunal regions too much
significance has been given to different scientific names, which show
neither relationship nor differences. Careful comparisons have not been
made in a sufficient number of examples.
I am fully aware of the almost non-existence of coral reefs in the
eastern tropical Pacific and the Marquesas Islands since perhaps the
time of the Tethys Sea. Ecological conditions are not wholly suitable
in the eastern Pacific for a typical coral reefs fauna because of the mas-
sive upwelling of relatively cold water. In addition there are few
island “stepping stones’ forming a suitable habitat.
Within the tropical Indo-West-Pacific region, in spite of the homo-
geneity of the fauna, occur several subfaunas. Although extensive pro-
fessional ichthyological collecting and study has been somewhat limited,
enough has been accomplished during the last 50 years to indicate cer-
tain island groups and regions as containing distinctive endemic species
and subspecies. Roughly these regions are: (1) East Africa, Red Sea,
Madagascar and Mauritius; (2) East Indies to Northern Australia and
the Great Barrier Reef to the Philippines; (3) Ryukyu Islands and
southern Japan; (4) Hawaiian Islands and Johnston Islands; (5) Ma-
rianas, Marshalls, Gilberts, Line Islands, Phoenix and Samoa Islands
and perhaps others; (6) The Marquesas and Tuamotu Archipelago.
Other island groups may be distinctive, too, but to prove it more careful
ichthyological revisional analysis of species will need to be made.
My comparative studies of wide-ranging genera, species and sub-
species in the tropical Indo-West-Pacific and Eastern Pacific indicate a
much closer relationship of these faunas than has been stated by zoo-
- geographers. As might be expected on the generic level the relation-
ship is very close, but on the species and subspecies levels there are dis-
-tinctnesses between Eastern and Western Pacific. Among the Island
groups of the Indo-West-Pacific the differences show up strongest on the
subspecies and racial level. This new approach or concept requires
careful analysis of species and of genera on a world-wide revisionary
basis.
Widely ranging species (used on a bread concept, perhaps super-
species) extending from the Pacific American shores to the east coast
of Africa, when studied intensively with the use of statistical methods,
color photographs of living fishes and basic color patterns of preserved
specimens, reveal that some of these so-called species actually are com-
posed of two, or more species, subspecies or races each more or less in-
habiting subfaunal areas.
A416 EIGHTH PACIFIC SCIENCE CONGRESS
To illustrate this concept I give herewith a few examples: Family
Acanthuridae, surgeon fishes; Acanthurus triostegus ranges from Pacific
American region of Clarion, Clipperton and Cocos Islands to the Afri-
can east coast. A. triostegus triostegus (Linnaeus) has the color pattern.
consisting of a single dark spot at base of pectoral and this form occurs
from the Indian Ocean to the American Pacific with the exception of
the Central Pacific and the Hawaiian Islands. t eee |e (BIMpny) wryo1ary9 “AT
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EIGHTH PACIFIC SCIENCE CONGRESS
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‘eau
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srsuandnd
(P2GL) szsuandnd yz
uuBwMydieqg susn{rind
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IPL uoyo “Yd,
petp BY enysoe vLhiw “YT
uugulyoieg susnfoau
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BYUZTES END 8njors
(Byue[eg) 49qq20 “YT,
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o1alovd
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j AN
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DISTRIBUTION OF INDO-PACIFIC LITTORAL HGLOTHURIOIDEA 447
| SIMPNY] wzeqauryos wimpruochys
eyusleas sdaowp enayy90109
(SIMpnT) weqaWYyos °*9
| Ua Aa eS pe rere
| I9INIG snyouoy snsoydorhyg
| AMI wILQDINQuD DYyAaYJ,
| Ted
| | LOZDINqup (snjosodAyy) snjosg
poe1g B enysor 109400 aU0hYy T
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(peatg a unysor)
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|
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IOYSiY asupupany YF,
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uUuBUIYpIag 2/9001DY
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uuBul
SnjOsdaUony, F,
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(uosdwyg) D2 wasn “LE
ABLUBILOT
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GAVN OILNGIOg
EIGHTH PACIFIC SCIENCE CONGRESS
448
oes
HBO
‘Tl ‘H sisuawmpjonpo.d py
Ossi snynosnu *
S|
[R2UL wns14107,UD DM0ZSOYIOLT,
(SImMpn'y) vipawsazus
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(uosduiys) Djoo2UWarD
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aedwesg snaipuyfia "9D
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DISTRIBUTION OF INDO-PACIFIC LITTORAL HOLOTHURIOIDEA 449
pie ie | | | | | | eee | rats Aequewoqg pso1ajaa +H
| | | | [ | | g | | souenA
a | = | | | 1 | | : I[Y2oy 2y900)0 mrunyzoshydey
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| | | : | | ieee | | -0G wouunyong vunjoajdvsag
| | | | : | | | | | | ALLO WO "TH vLodn.ja2 *q
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= | =e | i | | | I S| | = AByuUBWOg 2449“
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EIGHTH PACIFIC SCIENCE CONGRESS
450
| | | | | | | | | Bulpsy prwosyol 77
| | | | | | | | | | :duIp (uosdwyys)
| | =e | | | x | : | | | -ay] vurzodowna vidoufhisojdaT DlafLiqnjop vicnuhsojday
| | | ‘uos
; le el | | | | | eee es “dug véafuqnjop vzrdnuhig
ete | | lipsrses' (is | ees [peers Sese | sous syyeqne “y
= | | | Seetlins Je | | | | eH Wyapny “vy
i eee : = 1 | | | | | tex if ae TOYS susaur “VY
sits eres |e eel |. | | | | | | quoduery apyof -y
os | | 5 i | | | x | | | raduag sipovih pydvuhg (fedwmeg) s2p0016 “y
| | = | 4 | | a | ee | a | UdsiIIg sisuasnump vidouy
ee ee ees | | sa le See eel | | Jedues 07004 midvulig (taduieg) 77904 "9
| | | BS eax YIVIQ “I ‘H Dbz vynjdvuks (tedwag) ssw 9
| | tqedursg vif vidoulig
[ | | | | = | iF | | | : | = 28, WARIO “TI ‘YH viopum “9
| | | x | | x | | | deduiag vsiipur vidvulg (tad
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| | | |
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AVGILGVNAS
DISTRIBUTION OF INDO-PACIFIC LITTORAL HOLOTHURIOIDEA 451.
ie = ale a deal Wail i eles | dat eesiaae 2 r ee SuIpeH pnovdsyun “of
| oaks ick hi ; wae lee | yest se ees ss BUpOH avowns [ D? 1 GENE A cae ds Ne
e | ee | (Seles (9) + Na Qin) Re ape
3
ms I @Nyp a 1 @Ny,
8 e jie dye Mm ($) + Nm Qin) Re dd?
3
+ INEXOSB n) Le dM
Re Vd?
3\/3
24 dNn aes > aM,
— ——— ——M aga = = $
ot p dy » (9) po R2 m Tm dg? Ce)
3
where we have
39
A= ~ (2nR/3) , (39)
so that the ocean is supposed to be bounded by the meridians of 0°
and 120°, and the western and eastern boundaries are given by A = 0
and »} = | respectively.
2 diM
My, d m
Now it is possible to express an ae in terms of M,, (¢),
dy’
or
aM. ia
dy > ee
and
d*M 3
aes y= mM .(¢) -
Substituting (40) in (38) we have
D; d*N GING.
SMa (8) } 52 Se
m
On? 16x*R* das 8 47R? dy?
3/3
22 aANu i > 0? 1 ae D; 1 : a
Qn dA > ( a Sai oh one
— R2
3
© 1
530 EIGHTH PACIFIC SCIENCE CONGRESS
In order that this relation should be always valid, the coefficients
of M,,(¢) must vanish. Thus we have
Bil 228 GENE, y @N 9x/38 aNe
—_—_. iin va EL A SY tons ee SR se a
32 R2 on 327? 4 aX 477? dx
1 ; A 1
ae =( - = oy + 9-2 Pope iv + N, po dal,T, = (0) (42)
where T, is given by (34).
It may be anticipated from (39) and (40) that the values of Bi
are larger than that of ai,for any corresponding set of values of i and
m. But the ratio
D} 2 Ay
Re po NR?
is of the order of 10-* for the usual value of A; (=108), so that we
may neglect the terms of #? in the coefficients of N; in (42). Then
(42) becomes
nie oe Se ae
32 R2 dy gone 1 dy? TET GIN
1
on > (43)
7. DETERMINATION OF THE VALUES OF ai |
5 5 : aM,
The coefficients of M,,(¢) in the expansions of ; were eval-
bp?
uated as far as M,,(¢), the higher terms being neglected.
For the ocean under consideration, we have
Ma © a M, ($) + 8M; (¢)— 6M; (4) t
i + 4M, (¢) — 2Mg ($) ,
D a 9 | — 3M, (¢) + 20M. (¢) + 18M; (¢) ,
WA) tar @ 10Meerse (46)
we have for odd series
9 (N, — 3N; + 5N; — 7N, + 9N,)
D(N,) + 4747600y? x 4 — 0.548249 x 102° = 0,
OVSNae i 20N, = ISN. PING = 27 Ni)
D(N3) + 47476007? anil > HOMIE) See
9 (—6N, + 18N,; + 69N; —35N, + 45N,)
D(N;) + 47476007? ar SOI alo woul) 200—— 10)
9 (+4N, — 12N, + 20N,; + 148N, — 63N,)
D(N,) + 47476007? X 47 + 2.19300 x 102° = 0,
9 (-2N, + 6N, — 10N, + 14N, + 257N
D(N,) + 4747600;? x Aes 1.096499 . 1020 m0! :)
(47)
where the operator D stands for
d4 2 d
1D) = Fa, 1082323? — 14997110 -— (48)
dy? Gh
For even series, we have .
(LIN, = SIN, 4b TON, = TENG
+ 20 .N,,) + 5.45179 x 102 = 0,
GolGNs 4 43N—1O4N,, + 32Ne
— 40N,,) + 3.59829 x 102° = 0,
(SION, GE DAN, Se TNEUNG, == BOING
+ 60N,,) — 14.76753 x 102° = 0,
(ALINE, == GIN se DAN, ts ON,
— 80N,,) + 7.09512 x 102° = 0,
(NL, <4 GN, == ONG <2 GINS
+ 343N,,) — 3.54756 x 102° = 0,
(49)
D(N,) + 47476007? x
D(N,) + 47476007? x
D(N,) + 47476007? x
ale ee le
D(N;) + 47476007? X
3
D (N30) + 47476007? X —;
532 EIGHTH PACIFIC SCIENCE CONGRESS
where the operator D is also given by (48).
To solve the simultaneous differential equations (47) and (48),
we employ the method of indeterminate multipliers. Let the odd set
of equations be of the forms:
9
DN) GN, + E, = 0,
i
9
D(N,) + 2 CIN, + Es
aa
D(N,) + 2CIN, + E, = 0,
Fil
9
D(N;) + DCW, te 1
a
D(N,) + > CN, + E, 0,
= (50)
where the summation is made with respect to odd numbers.
Multiply each of the five equations in (50) by J, Js, 1;, l;, and l,
respectively, and add together; we have then
DUNE art Nast, tN a LNG oie LNA)
tC OC Cr, CN
0,
|
=
e So ei ci, it Cl, u Cr, WP ey) N,
ap (CRE se (CRM ae Og) ae Gg 8 Gu) a
sp (CHL ap (GR te Ga ae (Ga ae CEI) NY
+ (Ci, + C3, + C5 + Ci + C%)N,
Now let ees ee oie ee ae (51)
CU, + C3, + Col, + CU, + Cl, = Le
CU, + C3l, + CS, + Cl, + Ci, = Le,
7 : p 7 Oy as
and eliminate ae vis ‘i ee Git Co ee (52)
gene Si pa cr co =o
“3 CS atc Ce C7 or
C1 C3 Co — ¢ C7 Ce bo
“ROW. CWE ec tlt (kta
. : “3 “s Ce
GENERAL CIRCULATION OF THE PACIFIC OCEAN 533
This equation has five real roots. Let them be
£1, &3, &, € and &
and, corresponding to them, equations (52 will give five sets of 1,, l,,
5 op: Ulery Cove
ae ii, Ii, Yh, Hi, lh;
1 1 3 5 7 9
3 UB) (ES RS Bo Tes
1 3 5 7 9
Eney LE lost, 15, 1
Sen ibn wircenio
pee Ts As a aE ICR
1 3 5 7 9
Epcos p, p, 19, l. (54)
These five sets of roots and multipliers /’s will give Y,, and F,, as
Yt elaN InN, see EN are OTN oi IN es
| ta (I) Sa eae bY Oate yes (1) ley i a be 2
Ge Sle Buy Te ©) (55)
and the corresponding five equations
D(¥,) + EY + Eq = 0
(i = 1k, Be Oy 7/5 8) (56)
for ¥5, Vz, «8, Yo. a beygare no) longer simultaneous; and not. diffi-
cult to solve. The same, of course, applies to even sets, too.
Practically, the equation corresponding to (53) is
1—¢ + 8 — 6 + 4 — 2
— 3 20— ¢€ + 18 — 12 + 6 — 0
+ 5 — 15 69 — é + 20 — 10
— 7 + 21 — 35 148 —¢ +14
+ 9 — 27 + 45 — 63 257 — €
or
210830400 — 841564682 + 462522522 — 7877123
+ 4954 — = 0 (57)
where
=) 2] (Ganstoseiiess Y< BAN) (58)
and the five roots of (57) are
Ga 29011943;
Ca — 26 1028 ie
Ge Jan Bisse),
Gi 1464569045
Go 2A AOOT Ae (59)
For even series we have, corresponding to (57), (58) and (59),
d= 57 + 16 — 12 + 8 —
— 8 BG oy Pe — 16 + 8 = 0
+ 12 — 24 Non | ee ae: — 12
— 16 + 32 — 48 Aaya LG
ae AD) = a) ae (av —+80 toa ey
534 EIGHTH PACIFIC SCIENCE CONGRESS
5217079023 — 593115237) + 16671798? — 17245878
+ 715y! — y= (60)
where
y = £/(4.38649084 x 34) (61)
and
= 12.8567852,
ys = 51494636,
116.1536052,
ye = 207.4231320,
vo = SerOT1e42, (62)
8. DIFFERENTIAL EQUATIONS FOR Y’s AND THEIR SOLUTIONS
. From the numerical computations described above, the numerical
coefficients of the differential equations for Y,,(\; 7) were determined
as follows:
D(Ya) + 11514116,2Y, — 04037686 >< 1022 =" 0;
Dot LOST tiWGo72Ys 0.020421 cnlO22s— 0;
De) te 28880000872 — 2041449265 > 10220:
IDO) ae Oe] isa ae SATB ios) < MUAY = UU),
Da) Fo OSI SAOMO n2i5 oe Zonal o0o4 xe i020 sO:
(63)
and
D(Y,) -- 51883042n7Y, + 7.4929828 x 1070 = 0,
D(A) 207804544720 3393918 xo 0257— 10)
D(V,) + 46873322877Y, +. 258.843806 x 107° = 0;
De) 83701752725) 4) 158. 8661390 x 1025 = 10>
D(Yao) + V319885336n2¥55, a 290:023938) x 1022.0: (64)
where
| : d? d
1D) = anata 1082323? a 14997110 ol
and Ya, Ve, -- +» Yon Yo, 0. © 2) Yao Stand fon the tollowing expressions
in terms of N,,:
Y, = N, + 0.2167031N, — 0.0302211N,; + 0.0100338N,
— 0.0045539N,;
Y, = N, + 4.6332707N, + 1.6778105N,; — 0.2720794N,
+ 0.1018516N,;
Y, = N, — 7.3461297N, — 31.5044500N, — 13.18126660N,
+ 2.0803739N,,
Y, = N, — 4.2883468N, + 20.4004807N, + 99.0498144N,
+ 47.0163475N,, ;
Y, = N, — 3.6583547N, + 9.7849522N, — 40.0969663N,
— 245.9320935N,. (65)
GENERAL CIRCULATION OF THE PACIFIC OCEAN 5080
and
Y, = N, + 0.3172231N, — 0.0501698N, + 0.0180624N,
— 0.0086497N,,,
Y, = N, + 4.1262613N, + 1.5874177N, — 0.2597861N;
+ 0.0995609N,,,
Y, = N. — 5.4990870N, = 23.8405548N, — 10.3129949N,
+ 1.6109253N,,,
Y, = N, — 3.0874234N, + 13.8285447N, + 68.6295877N,
+ 33.3180647N,,,,
Y,. = N, — 2.5712654N, + 6.4271377N, — 25.6939046N,
— 160.9722444N,o. (66)
If the 10 functions Y,, Y,,..., Yy) can be determined by solving
the differential equations (63) and (64), it will be possible to compute
N, (A; 7), No (As 9), - - -» Nio (A; 7) from the following expressions which
are the reversions of the expressions (65) and (66).
= + 1.0650221Y, — 0.05878696Y, — 0.00491292Y,,
— 0.001038174Y, — 0.000284101Y,,
= — 0.2793058Y, + 0.2586992 Y, + 0.01644431Y,
+ 0.003283144Y, + 0.000879072Y,,
+ 0.1254434Y, — 0.07711532Y, — 0.04050495Y,
= 0:006251173Y, — 0.001571970Y,,
NGA = 0.05969848Y, + 0.03367969Y, + 0.01083299Y,
1
+ 0.01265900Y, + 0.002526788Y,,
N, = + 0.02520969Y, — 0.01264167Y, — 0.003642393Y,
— 0.002365708Y, — 0.004554906Y,. (67)
and
N, = + 1.1172140Y, — 0.1028957Y, — 0.0109283Y,
— 0.0026156Y, — 0.0007745Y,,,
a = — 0.3385977Y, + 0.3066091Y, + 0.0247985Y,
+ 0.0055792Y, + 0.0016107Y,,,
N, = + 0.1613919Y, — 0.0943220Y, — 0.0548464Y,
— 0.0096171Y, — 0.0026064Y,,,
Nee —-0:0792995 >. = 0.04207 TY 00175807,
+ 0.0184664Y, + 0.0040001Y,,,
Nig= + 0.0314504Y, — 0.0160186Y, — 0.0050095Y,
— 0.0034369Y, — 0.0069853Y,,. (68)
Substituting the functions N, (x; 7), No(xim), - - -» Nio (x3) thus
obtained in (30), we shall obtain the expression for ¥, (x,y; 7). Further
substitution in (29) will give the solution of the problem as
1 ww Pp 7%
LOC 2) = oD. 2yMn(y) {a (x; n) cos ) = )a (69)
536 EIGHTH PACIFIC SCIENCE CONGRESS
The method of solving equations (63) and (64) and the evaluation
of the integral:
ce
Nin (*3 ( ak je
Grvcerncn (ala
will be discussed in the following section.
9. INTEGRATION OF THE DIFFERENTIAL EQUATIONS
The next step will be to solve the ten differential equations (63)
and (64). Let any one of these equations be
pe — 10se3o3eemen 1907 10
4 dn? dn
where b and c are constants assigned to each of these ten equations.
Since a particular solution of this equation 1S
+ by?Y +-+Cc= 0 (70)
y, =e (71)
n?
the general integral of (70) will be of the form:
c
2) =e Age er IBIS (Crags ot) [DAN a ma (72)
where a, 8, y and § are the four roots of the algebraic equation:
O = 1082323 7202, 12997 MOG) 4 10ne — 0 (73)
and A, B, C, D are constants to be determined according to the con-
ditions:
Y(0) = Y(1) = 0;
y"(0) = Y(1) = 0. (74)
The equation (73) has four roots a, 8, y and § for any given value
of », and A, B, C and D all depend upon a, £, y and 8.
The parameter 7 varies from & to oo, and the values of a, B, y, 8
all depend upon 7. When yn is very large, these four roots are approxi-
mately
020/307 57);
— 1040.3075y,
Vit (O} LO82323)rz6
= — (0/1082323) 2. (75)
As 7 decreases, a, 8, y and § also change gradually. For » less than
a certain value between 7 = 0.4 and » = 0.3, B and § become complex
conjugate. As » approaches 0, a, 8 and § approach finite values, while
y decreases indefinitely as con?. “Thus we have, when yn — 0.
M2 DR
I|
Sai ea (76)
GENERAL CIRCULATION OF THE PACIFIC OCEAN 5387
where
p = (14997110)%,
3
G | = oe (77)
For the intermediate value of 7, these four roots vary continuously ex-
cept 8 and § which change from complex conjugates to real as 7
increases from 7 = 0.3 to n = 0.4.
Of course, there are 10 series of such four roots of 10 equations
(70), each varying with the parameter 7.
The constants 4, B, C and D can be, of course, expressed in terms
of a, 8, y and §. Thus the solution Y becomes, when £ and § are com-
plex conjugates of the form
B=+ pt qu J 12 — Ue (78)
, uf
Y= 41 te ex(h—1) — ev)
Oa ay; Oeareey,
a
a ( ev — 1 eco ga
G5
a=
+ ( a Pe tase aa) =) e-P\ sin ga bY, (79)
ae) q q
and, when a, f, y, § are all real,
v= [is x ea) +4 : Ne ket Ua ys eBr
Qany, B-8& a-yf-8
1) 4 RUSE a Sie gir +e] 12
Teay [Eee Ws Coolers nah dcdiag
(80)
where Y, is the particular solution given by (71), of the equation (70).
When 7 increases y also increases. If we can neglect e€-7, the ex:
pression (80) will be further simplified, and we have
{ y 8 a
a—y p-8 a—y
: f
— ae ce
g—o* (* (81)
Since Y, is given by (71) as
b/c
Hale AGE
2
the solutions of the equations (63) and (64) will tend to zero as » in-
creases indefinitely.
The values of the roots a, 8, y and § of each of the 10 equations
given by (63) and (64) were computed numerically and given in Tables
V-XIV.
Ol
(oy)
10.)
EIGHTH PACIFIC SCIENCE CONGRESS
10. COMPUTATION OF THE CURRENTS
In order to calculate the distribution of the currents at various
levelss we had ‘first toicompute ¥q\(\;)s) Yo (sim) nee (A; 7) accord-
ing to one of the expressions (79), (80) and (81) for
A = 0.0000, 0.0025, 0.0050, . . ., 0.0500, 0.0550, 0.0600, . . .,
0.1000, 0.1100, 0.1200, 0.1300, . . ., 0.2000
and for
ae WAOOE, 2 oo vont 0 BHO, oo dey ONO).
For larger values of 7, we have
Oa 1040.3075,
B = — 1040.3075n,
y = + (b/1082323)%,
8 = — (b/1082323)% (82)
very accurately, while Y, () are all very small, so that Y,(A; 7) will be
approximately given by
a i Sey G1) — ek =o
| 7 (83)
where y, and c are independent of 7. It will be more convenient to
leave (83) as it stands rather than to compute their values against ».
These values of the ten functions Y,,(\; 7) may be then converted
into the functions N,,(\; 7) by virtue of the formulas (67) and (68).
Substitutions of the functions N, (A; 9), No(A3; 7), Ns(Ain), - - 3
No (A; 7) into the equation (69) give the complete solution as
ee ub
Wr (Go y, Z) = On ai (y) ie (A; ”) cos ( 2D, 1) dr,
isnt ed Tele
(84)
To evaluate the uatceral
fx, (A; 7) cos (= =n ) dy,
we have computed the functions N,, (\3; 7) for
oa OOS OM Opec 8 een IOS PO ON S65: HOD
and the process has to be carried out numerically between » = 0 and
7 = 10.0. For larger values of », we may use the approximate for-
mula (83).
Let the values of a function F (yn) for » = 0, h and 2h: be aswiae
and F, respectively. Then the interpolation formula in this interval
of » will be given by
ua — 3F, + 4F, — F, ) Fy — 2F, 4 F, 0 2
BG) Bieta) 0 Tapes Ve) os 9 hows
GENERAL CIRCULATION OF THE PACIFIC OCEAN 539
Then we have
2h 2h
Tz TZ
2) cos i= dp = io feos 2D," dn
= Baa ee 4h — Fe
Bene Aad) 3 cos lam 7 Idy
SS AO ae Jae k ( 1 ya
opis ie cos op,” 7
or
2h
fea z
fr (m) cos OD, nay = = (a, — 3b,+ ¢,) Fo
+ (4b, — 2c.) F, + (0; + 63) Fe
where
a i Zz
Te a
aol Secs (57)a ( oy (an, zn)
2D,
Chae ae
oa Som (x)
aA Ope. Messy 9D, n
ue op, h Hy Dh
ie 1 i. D OD, eos om + op 2h)— 2¢ sin )
bey Giese wz 2 (86)
( 7) ( oD! 2h)
For larger values of 7, we may express F (yn) in the form
r Lies fgg Bei cha
F(y) = Fy + Soe i ae aly Op? Ge at)?
where F_, F,) and F,, are the values of F(y) for y) — h, no and 4
+ h respectively. We have then
noth xz oe =
fie cos (a7) dy = (— dy + 6)F_y + (2 — 23)Fo
79>—h rete
+ (0; + ¢5)F iy (87)
540 EIGHTH PACIFIC SCIENCE CONGRESS
w= f1-3(a) fe (s.")
= {a(a) - aS )t= (ar)
C= Wee Cay 1) bo oa) (88)
The integration was carried out taking h = 0.1 in the interval
0 = » 1.0; and h = 1 for the interval 1.0 S y= 10.0. For larger
values of y, integration was carried out by using the formula (82)
which is only inversely proportional to 7?. In this case, we have only
to evaluate the we
Ve fF ol -1 Jay (89)
The aes were rather tedious and took three computers
more than six months to complete the surface, 1/2D,, D,, 3/2D,, 2D, and
3D,. The values of a, 8, y and § which are the roots of the quadratic
equations (73) with » as a parameter and computed for the necessary
values of y, are compiled in Tables V to XIV (omitted).
The values of the stream-function were computed for the western-
most 1/5 part of the entire expanse of the ocean, and the streamlines
were drawn for the layers z = 0 (surface), 1/2D,, D,, 3/2D,, 2D,, and
3D,. The computations were not carried out for the deeper levels and
for the part to the east of this area, partly because we did not have
enough time to compute, and partly because the central and eastern parts
are not as interesting. We have only a very slow zonal flow in the centrai
part and very diffuse meridional flow close to the eastern coast of the
ocean. Indeed, the California and Peru Currents are considered to be
produced by local winds as proved by Munk (1950).
The circulation patterns in the area close to the western coast were
obtained from these computations, and illustrated in the Figures 3, 4,
5, and 6. The discussions for them will be given in the following
paragraphs.
Table II gives the velocities of the western current in the subtropic
gyre corresponding to the Kuroshio, or the Japan Current, at the depths
z = 0 (surface), 1/2D,, D,, 3/2D,, 2D, and 3D, along the 33° N parallel,
which is the swiftest part of this mighty current. These velocities were
computed by the formula:
v=(& =) S _ Qo + AA) = ¥ Ao — Ad)
0
linear ~ linear distance of 2AX
3
041
GENERAL CIRCULATION OF THE PACIFIC OCEAN
‘siajeu Ul passeadxa s1 *q o10q M4 a/b Aq satzI00eA esayy ATdyynw ‘w Gy, wey, Jaq}0 *"Gq yo saNnteA aAOJ AWIDOTOA ay} 423 OF,
Sissel =— > ils —S=.- 8o- SS — 03 6g 6 OTT 62 0 (9as/w9)*qg = 2 ye Aqr0TOA
fae Ole oe Coe 6 II ty 18 6ci LE LOL 0 (o0s/m9)"*qZ = 2 7e Aqro0joA
8- 6 Ve Bie Gg 1Z LY VOm 67 ie SOR = een (as /w9)*qZ/g = 2 ye AALO0TOA
= 9- 8- G- L 8 3h OD Se ie (9es/u19)"q = 2 4a Aq00T9A
Pv T 0 v LT &P 8 Cole = 98 = 90G = OSTa <0 (908/19) *qQZ/T = 2 ye ApD0PaA,
TW: 8 L ral td 2g v6 OV ee OCI LG) es CO 0 (998/t9) AQToofeA eoejaing
Giga OSG = Seon 00G = oT. 0Sh = cok 200K cv 0g GS 0 (wy) ATepunog 4seM WoOIZ ooULySIC
w ¢), = 7q ONIWASSY
“IATIVAVd N o&& GHL ONOTV “Gg GNV *qz “°d2/E “G2/T ‘0 = 2
SHLddgd INAYGIAIG LV OIHSOUNY BAL AO » ALIOOIVA GALNIWOD
Il WTavai
542 EIGHTH PACIFIC SCIENCE CONGRESS
and taking D, = 75 meters. Because the velocity is inversely propor-
tional to the quantity D,, we can compute it for any other value of D..
For this we have only to multiply these figures by 75/D, where D, is
expressed in meters. The maximum surface velocity of 217 cm/sec
agrees with actual observations very closely.
Table II gives the distribution of EW-components along a meridian
24° of longitude east of the western boundary, or 1/5 of the entire
east-west expanse of the Pacific Ocean off the western coast. At this
distance from the western coast the coastal. effect nearly vanishes and
the pattern of the circulation consists of approximately zonal flows.
In this table the value of D, was again assumed to be 75 meters. Dis-
cussions concerning these results will be made in the following para-
graphs.
1]. SURFACE CIRCULATION
The numerical result for the horizontal circulation has been worked
out for several levels specified by the ratio z/D,. We show here those
Ob thepsunfiace (ai — 10) yz De 25) (2 // De —— al se AD == 2
and z/D, = 3. The most important of them is, of course, the surface
circulation, and Figure 3 shows its pattern. The gross features of the
current distribution on the surface thus do not seem to differ much from
those given by Munk (1950) and by the author (1951) for the distribu-
tion of mass transport streamlines. Because of the considerable labor
contained in the calculation, the computation is confined only to the
western part of the ocean bounded by two meridians ) = 0 and \ = 0.2,
that is, 24° of longitude apart. Choice of the western part of the ocean
for the computation was made because the circulation patterns in that
section are more complicated and hence more interesting. In the cen-
tral part of the ocean we will have indeed a very slow motion approxt-
mately in east-west direction, while very diffuse meridional motion will
exist close to the eastern coast.
We have a number of gyres in the surface circulation corresponding
to those obtained in Munk’s (1950) and the author’s (1951) results with
respect to mass transport. We have a broad gyre with strong western
current flowing north in the latitudes between 20° and 40° N and
corresponding to the Kuroshio or Japan Current. We also notice one
boundary vortex, but the secondary boundary vortex is not distinct.
We have a subtropic gyre with the western current flowing south. This
corresponds to the Mindanao Current. Of course, we have a faint sub-
arctic gyre corresponding to the Oyashio or the Kurile Current.
On the surface of the Southern Pacific Ocean, we have western
currents flowing north a little south of the equator and in the sub-
antarctic latitudes. Between these two we have a strong current cor-
GENERAL CIRCULATION OF THE PACIFIC OCEAN 543
TABLE III
ZONAL DISTRIBUTION OF EW-—COMPONENTS OF OCEAN CURRENTS EXPRESSED: IN
em/sec, ASSUMING D, = 75 m (++ EASTWARD, — WESTWARD)
LAT. z= 0) 2 —) 1/2D) z= DI 2 — 3/2D 2) — 2D, z — 3Dy REMARKS
(SuRFACcE)
60° N 0 0 0 0 0 0
Dili NI 0. =e Duo WP aah esl tO ea Oi PA CLIC
54° N SOT ee OMe an I ek 2p eo eee oo Current
FyieeIN| si BH Se BO sk BR do Oey oe OI a
48° N wDo S-ehikGe > 3:6 ee 6. a2 ae
45° N 20:40 Eb toto El Os Ou eg! Wiest
42° N TEAMS Salle aE SE ee Se Ess) \ abe!
39° N SE SL TS) OS SE Wie Se Rea Der beg
Omen 26 YQ a2 AB 2 RE -e aM +6 -2G chad
SOmEN| HELO: demi OL Mia A te OCC th toto lin tem eore
SO mee se AC OM at et ie tO Obie Un (PAGE vie
PA? INS ies — dE — 1s I BS ED INoreln
24° N = WEA oS Wl op Re Os Se LIL Tropien cop ereal|
Pilea WIN = 1S — 1s = O8 = WH 8 i> Sa. -Oumarinte
18° N ae Rese SOM Reeve Gana Ota soo. tan le
oe IN = Tees = AD) Sees HD Hell =A!
UA? IN Cale Ah eae td WP 0 J Oe ao) Oe SS -Os3
DSN BA ean ue tee eA) ee ore me Om quatorial
6° N Seen = 1.0) EV 9.8) ee 6.5). 14:8 Counter.
Sani de te TA Eg elle sy sat (Gabber ele
0° Soro) Osan en iieOl tO Se Ger ee bee
eo = OY: 22°10 46 25 sb Be se Be . ab aul
6° S$ eG SO ie OA co AIC ec OM Cone ogee eer ()ib
aS eg Oc Ameer ae OS Oi mene bic COSI. emus)
12° FS} = BI) == GES 1s} RAL RS i Souda
lee =a A bef Sp OI Geers erm Ube Le rr Lt bap 9.1 —5.9 Equatorial
18° §$ Sl Sey e aet ARO OS eam ONy era Ok Gee ee Ava nN Current,
Fall tS: = HONG I) 74 CO = Oe) == 0 = By
Blo SR EE BE lls OBO) a alee
PANE TS) Sie, == 7 0f8) 06 = 04 703 0
30° S Sea to G5 = e508 ea 3tOs 3.0) ny,
oR SS) SUA) eo - O58 - Th + 8. 4a AWese
365 5 JL OO) SS Ios) SE BED Sen SE Cbs Stash Aihara
39° S aE | BOK IE IZ) SIP tl ae ID igbis
42° S$ +200 +164 +1381 4+125 + 84 45.6
AUS S) +138.7 +106 + 7.9 + 60 + 47 + 3.0
48° § HE NO) 2S Pate ete aly) 0 == ON = WG
mt? iS) = OE Giana aaa AS Ohi em Ose ad Ae Ole Memes oS
54° S GD GS iis ONE ee SO ae O Abe iA. Oy Ee PAILLATCEIC
si? S = ALS ere Dla On AeA oe Ourrent
E44 EIGHTH PACIFIC SCIENCE CONGRESS
responding to the East Australian Current, though actually this current
never develops so strongly because of many passages connecting the
Southern Pacific to the Indian Ocean through the numerous islands
and archipelagoes in the Australian-Asiatic Mediterranean. Had we
not these passages together with the Southern Antarctic Circumpolar
Ocean, we could have a much stronger western current in the South
Pacific Ocean than actually observed.
It looks also rather strange that we do not have any strong west-
ward flow in the latitudes between 5° N and 2° S. Actually the north-
ern margin of the South Equatorial Current is in this zone. This comes
as the consequence that the Equatorial Counter Current appears in our
theoretical result much broader and much more diifuse than actually
observed. ‘This is also the same in Munk’s and Hidaka’s results. The
theory of the Equatorial Counter Current has been attacked and ex-
plained by several authors (Montgomery and Palmén, 1940, Neumann,
1947) in some other ways than ours.
12. EVALUATION OF THE COEFFICIENT OF VERTICAL MIXING
The streamlines in Figure 3 are drawn for an interval
Av = 250 x 10'°/D, cm?/sec.
of the stream function. The velocity can be determined as the ratio
Aw /Ax, where Ax is the actual distance between two consecutive stream-
lines. Because these diagrams are not drawn in a common scale for
the north-south and east-west directions, it would be rather laborous
to compute the magnitude of current velocity for all parts of the Pacific.
Still it will be easy to know it when the streamlines run in exactly north-
south or east-west directions.
The values of the stream function at several points along the 33° N
parallel are computed as compiled in Table IV. Assuming the Pacific
Ocean is 10,000 kilometers across in its east-west direction, we obtained
the velocity of the Kuroshio at its swiftest zone, which is located approxi-
mately 55 km off the coast, to be 329 cm/sec, 219 cm/sec, 165 cm/sec,
and 110 cm/sec according as we assume D, = 50 m, 75 m, 100 m and
150 m, respectively.
Actual velocity of the Kuroshio has been estimated at approximately
3 to 5 knots, or about 150 to 250 cm/sec in its swiftest zone. From
Table IV we recognize that the computed velocity of the Kuroshio,
assuming for D, a value between 50 m and 150 m, agrees with the ob-
served values fairly well. ‘The previously determined values for D, fall
mostly in this range also. ‘This enables us to compute the values of
vertical coefficient of mixing from the formula (18). The above values
of D, correspond to the values 188, 422, 750 and 1688 g/cm/sec of A,
545
GENERAL CIRCULATION OF THE PACIFIC OCEAN
s/uo g ¥ Vv 9 rae 9% LE eL GOL 60T 28 go :u OST = *d |
s/uio g 9 9 6 61 68 OL aye Ne RE eas) SUD *q 101 AqTOOTOA
s/Wd TT 8 L Ho Ea A OT 1m GL = “Cf 10 pemmaure
s/o 9T ZT as 8T 88 8L we ie ab eB —ae O Us "a =
*d
—— eC BG 95S 88 o6t o68 VOL Gé60T OLST OS9T FSst 09 = ay /4V
s/moyOT
“al aa
== SG 1S 86 ad G6 cet 3c oro G8 S18 cay = a
s/,m00 10
wy GZ 066 46s 002 GLE Ost Get oot gL os ga Q = Arepunog ysoM WOIZ eoueystd
@LZ0° 0&Z0° ¢2z0° 0020" SLTO QSTO’ zto’ O0TO’ 200° 0900" Gz00 0 = X
qaATIVaVd N o$§ GHL Ssouov OIHSOUNY AHL Ao ALIOOTAA DOVIINS TVOLLAUOUH [, LO NOILVLNd NOD
AI @1avVib
546 EIGHTH PACIFIC SCIENCE CONGRESS
respectively. These are, of course, values consistent with the results
derived from many other different sources. (Sverdrup, et al., 1942).
13. SUBSURFACE CIRCULATION
Figures 4, 5, 6, 7, and 8 show the horizontal distribution of stream-
lines in the level 14D,, D,, 1/4D,, 2D,, and 3D, below the sea surface,
respectively. All give patterns similar to the surface circulation shown
in Figure 3. We have western currents and a boundary vortex attached
to each gyre. The only difference noticed is a general subsidence of
the motion as we go down into deeper layers. Still, we see that the
intensity of motion is only reduced to as low as half that of the sea sur-
face even in the layer 3D,. Figure 9 shows the comparison of the cur-
rent velocity profiles along the 33° N parallel at several levels to that
on the surface of the sea assuming D, = 75 m. The maximum speeds
are seen at about 55 kilometers off the western boundary. Although
the Japanese Islands are not disposed parallel to a meridian, the above
result agrees with the observed profiles of this mighty current quite satis-
factorily. Another result of particular interest is that, at a distance
larger than about 150 km, there is a flow to the south with much larger
velocity than in upper layers. ‘This counter current reaches a maxi-
mum speed of 20 to 30 cm/s at about 200 km off the western coast,
despite the practically motionless upper layers. Figure 10 gives the
comparison of the zonal distribution of EW-components along a meri-
dian 24 degrees of longitude to the east off the western boundary. In
this longitude it is expected that the influence of the western boundary
nearly vanishes and the actual flow pattern of the Pacific circulation
is disposed mostly as a zonal current system. The velocities of the
current in these diagrams were computed assuming D, = 75 meters.
For computing the velocities when the value of D,, is different, we have
only to multiply these figures by 75/D,, where D, is expressed in meters.
If we assume, however, that the value D, = 75 m-is consistent, we have
for the maximum surface velocities of North Pacific Current, North
Equatorial Current, Equatorial Counter Current, South Equatorial
Current, and Antarctic Circumpolar Current 22, 19, 8, 23 and 23 cm/sec
respectively. They are reduced to 18, 16, 8, 18 and 18 cm/sec respec-
tively at a level 14D, and to 11, 9, 8, 9 and 10 respectively at 2D,. The
Equatorial Counter Current remains nearly unaltered in its speed in
all depths compared above.
14. VERTICAL VARIATION OF THE CURRENTS
The most important objective of the present research is to get a
certain idea about the vertical structure of the wind-driven circulation
in the Pacific Ocean. ‘This will be, of course, impossible to obtain from
GENERAL CIRCULATION OF THE PACIFIC OCEAN DAT
former theories which have been mostly propounded with respect to the
mass transport.
Since the problem is three-dimensional, the numerical computation
is rather tedious. For this reason the author has not yet been able to
finish the computation below the level z = 3D,. Still we should be
able to expect some important conclusions from what has been com-
pleted thus far.
First of all it is very interesting that the wind-driven currents exist
in a layer much deeper than that expected from: the classical theory of
Ekman (1905). According to Ekman’s theory, a wind-driven current is
confined to the surface layer about D, thick, and we can expect prac-
tically no drift current at a deeper level except very close to the equator.
From cur computation, it can be shown that the current velocity does
not drop as low as half the surface value even at a level 3D,. Hf we
take D, = 75 meters, this depth is 225 meters.
This conclusion will be helpful for us to understand the fact that
wind-driven currents can penetrate into a layer several hundred meters
deep, a layer several times as deep as that expected from Ekman’s theory
as the limit of the wind-driven currents. This implies that the motion
of water in most parts of the oceanic troposphere could be produced
by the stresses of the permanent wind system prevailing over the oceans.
In other words, the winds are responsible not only for the currents in
the skin layer of the ocean, but also for the most part of the circulation
in the oceanic troposphere.
We have long considered that the winds are responsible only for
the current motion in the surface layer of about 100 meters thick. This
depth is nothing but the “depth of the frictional influence’ defined
by Ekman. To explain the circulation in deeper parts of the tropo-
sphere, we had to assume a very strong convection current and slope
current. Still we had a distinct difference in the circulation patterns
between the troposphere and stratosphere. “These circumstances have
made several problems very much complicated. Defant (1928) defined
the troposphere as the part of the ocean in which we can expect strong
currents due to violent turbulence and convection. Still we can have
violent convection in the seas of higher latitudes beyond the polar
fronts which are no longer defined as troposphere. The conclusion
that the drift currents penetrate into much deeper layers than D, is
much in favor of the definition of troposphere that this is the upper
layer of the ocean in which strong currents are present.
‘The explanation of the result that we can have a strong motion
even in a layer several hundred meters deep might look possible by
assuming slope currents which would be produced as the effect of purely
548 EIGHTH PACIFIC SCIENCE CONGRESS
wind-driven water masses piled up against the land barriers. As a mat-
ter of fact, Ekman’s theory assumes no boundaries and a constant lati-
tude. We can prove the existence of slope current in an ocean having
boundaries partly or completely enclosing it. The slope current is
uniform from the surface down to the bottom. This fact seems in
favor of the theoretical result we have obtained. Still, we must give
attention to the fact that the velocity of slope current is always inversely
proportional to the depth of the sea. When the depth is large as we see
in the actual oceans, the slope current will not be strong enough to
account for those large velocities we have obtained at the depth twice
or three times as large as D,.
We don’t know an appropriate explanation of the theoretical re-
sult that the effect of winds can be felt at a depth several times as large
as Ekman’s depth of frictional influence. It would be hoped someone
may be able to solve this question satisfactorily in the near future.
15. SUMMARY
(1) A theory of the general circulation of water in the Pacific Ocean
produced by the semi-permanent wind system prevailing over this ocean
is propounded.
(2) The velocity is used to express the water motion which has
formerly been explained by several authors in terms of mass transport.
(3) The Pacific Ocean is considered to be a rectangular ocean ex-
tending from 60° S to 60° N latitudes and from 0° to 120° longitude,
and a zonal distribution of the wind system determined from actual
observations has been assumed.
(4) The effects of horizontal turbulence and the meridional varia-
tion of the Coriolis forces have been taken into account.
(5) The patterns of horizontal circulation are obtained in terms
of streamlines for the sea surface and several deeper layers specified by
the ratio z/D, where z is the geometrical depth below the surface and
D, the depth of the frictional influence, a measure of vertical turbulence.
(6) Surface circulation has a pattern similar to that actually ob-
served and does not differ much from Munk’s result obtained in terms
of mass transport. We have very strong western currents and boundary
vortices.
(7) The magnitude of the Kuroshio and other western currents
was computed from the distribution of the streamlines in each level.
The velocity is inversely proportional to D, so that we can determine
it by assuming an appropriate value for D,. A value of D, between
50 m and 150 m gives values most reasonable and consistent with the
actual observations.
GENERAL CIRCULATION OF THE PACIFIC OCEAN 549
(8) Subsurface circulations also show similar patterns except for a
general subsidence as we go down into deeper layers. Still, it is remark-
able that we have far stronger currents than expected from Ekman’s
classical theory even at a depth much larger than Ekman’s depth of
frictional influence at which we can scarcely expect any motion except
very close to the Equator. This seems to show us that the winds are
responsible for the most part of the tropospheric motion of water.
16. ACKNOWLEDGMENTS
This research was initiated several years ago. Due to the great
amount of computational work, however, the author had to ask finan-
cial aid from the Ministry of Education, Japanese Government. Actual
computations have been carried out in Tokyo by Miss T. Osada, Miss T.
Yoshimura, and Miss K. Maruyama since December, 1951.
The completion and publication of this work were accomplished
at the Agricultural and Mechanical College of Texas. Several persons
in the Department of Oceanography helped greatly in its preparation.
The author is very much indebted to Dr. Dale F. Leipper, Head of
the Department, for his kind suggestions and advice. Mr. Robert O.
Reid was also greatly interested in this research and gave several sug-
gestions to the author. Dr. Walter Saucier was kind enough to check
the mathematical analysis and the English. Mr. Richard M. Adams
and Mr. George B. Austin assisted the author in preparing the manu-
script. Dr. Walter H. Munk of the Scripps Institution of Oceanography,
University of California, and Mr. H. Stommel of the Woods Hole
Oceanographic Institution kindly furnished the author with data of
wind stresses in the Pacific Ocean which enabled him to determine the
meridional distribution of the semi-permanent wind system.
It is the author’s utmost pleasure here to express his deepest thanks
to all who helped him in carrying out this research.
June 17, 1953
REFERENCES
DEFANT, ALBERT. 1928. Die systematische Erforschung des Weltmeeres.
Gesellsch. fiir Erdkunde zu Berlin, Zeitschrift, Jubilaums Sonderband.
p. 450-505.
EKMAN, V. W. 1905. On the Influence of the Earth’s Rotation on Ocean
Currents. Arkiv for Matematik, Astronomi och Fysik, Stockholm 1905-
06, Vol. 2,-No. 11, p. 1-52.
Hmaka, Kosi. 1950. Drift Currents in an Enclosed Ocean. Part I. Geo-
physical Notes, Tokyo University. Vol. 3, No. 38, p. 1-23.
1951. Drift Currents in an Enclosed Ocean. Part III. Geo-
physical Notes, Tokyo University. Vol. 4, No. ai jos olen)
550 EIGHTH PACIFIC SCIENCE CONGRESS
MONTGOMERY, R. B. and EK. PALMEN. 1940. Contribution to the Question of
the Equatorial Counter Current. Journal of Marine Research. Vol. By
Now J pedal 133,
Munk, W. H. 1950. Wind-driven Ocean Circulation. Journal of Meteorol-
ogy. Vol. 7, No. 2, p. 79-93.
MUNK, W. H. and G. F. CaArripr. 1951. On the Wind-driven Circulation in
Ocean Basins of Various Shapes. Tellus. Vol. 2, p. 158-167.
NEUMANN, GERHARD. 1947. Uber die Entstehung des aquatorialen Gegen-
stromes. Forschungen und Fortschritte 21/23 Jahrgang Nr. 16/17/18.
1952. Some Problems Concerning the Dynamics of the Gulf
Stream. The New York Academy of Sciences Transactions Ser. II, Vol.
14, No. 7, p. 283-291.
Rew, R. O. 1948. The Equatorial Currents of the Eastern Pacific as Main-
tained by the Stress of the Wind. Journal of Marine Research. Vol. 7,
No. 2, p. 74-99.
STOCKMANN, W. B. 1946. Equations for a Field of Total Flow induced by
the Wind in a Non-homogeneous Sea. C. R. (Doklady) Acad. Sci. URSS
N.S. 54 (5) p. 403-406.
STOMMEL, Henry. 1948. The Westward Intensification of the Wind-driven
Ocean Currents. American Geophysical Union Transactions. Vol. 29,
p. 202-206.
SVERDRUP, H. U. 1947. Wind-driven Currents in a Baroclinic Ocean; with
Application to the Equatorial Currents of the Eastern Pacific. National
Academy of Sciences, Vol. 338, 318-326.
SVERDRUP, H. U., et al. 1942. The Oceans, their Physics, Chemistry and
General Biology. Prentice Hall, Inc., New York.
GENERAL CIRCULATION OF THE PACIFIC OCEAN 5DbiL
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Fic. 1.—A Rectangular Ocean comparable in size to the Pacific Ocean.
552 EIGHTH PACIFIC SCIENCE CONGRESS
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SOUTHEAST TRADES
WEST WIND DRIFT
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Fic. 2.—Assumed meridional distribution of wind stress.
553
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depths expressed in cm/s, when D, = 75 meters. (To get the velocity
for other values of D, multiply these velocities by 75/'D, where D, is
expressed in meters.)
A CONTRIBUTION TO THE THEORY OF UPWELLING
AND COASTAL CURRENTS *
By Koji Hipaka
Geophysical Institute
Tokyo University, Japan
1. INTRODUCTION
There have been several descriptions of the upwelling noticed off
California, Peru, West Africa and other coasts by Thorade (1909),
McEwen (1912, 1929), Gunther (1936), Defant (1936, 1952), Sverdrup
(1931, 1938) and Sverdrup and Fleming (1941). The explanation of
this process given by Sverdrup in 1938 is worth attention. According
to Sverdrup and Fleming, it is known from the analysis of the water
masses that the water taking part in the process of upwelling off the
coast of Southern California originates mostly in the layers from 200
to 300 meters below the surface. ‘These are, however, all qualitative
discussions and it has been as yet not possible to explain this phenome-
non theoretically and predict the velocity and width of the coastal cur-
rents produced by the prevailing winds. Very recently Defant (1952)
made a theoretical explanation assuming a sea consisting of two layers
of water with different densities. “The present research is an attempt
to solve this problem mathematically and to draw some quantitative
conclusions concerning this process, which is very important in all fields
of oceanography.
The explanation of the upwelling seems to be satisfactory only by
treating this problem thermodynamically as well as hydrodynamically.
The following discussion will, however, be made only from a purely
hydrodynamical standpoint, on the assumption that the seawater is of
uniform density. ‘This is a necessary consequence for simplifying the
mathematics, but the author believes to have been able to obtain some
results which are consistent with certain facts observed in this process.
It has been noticed that the upwelling takes place most favorably
when, in the northern (southern) hemisphere, a wind blows in such a
manner that the coast is on the left-hand (right-hand) side of an ob-
server who looks in the direction of the wind. ‘Thus the upwelling off
the coast of California is most remarkable in early summer when north-
westerly winds prevail for several weeks nearly parallel to the coast.
+ Published in the Transactions American Geophysical Union, June 1954, v. 35, No. 3,
p. 431-444,
5D7
558 EIGHTH PACIFIC SCIENCE CONGRESS
consideration. And it may be stressed that the horizontal mixing seems
to play the most important role in the theoretical explanation of the
process of upwelling.
2. ‘THEORY
Consider an infinitely long straight coast coincident with the axis of
y, and take x-axis perpendicular to it in the offshore direction. (Fig. 1).
Suppose a wind of constant force and direction is blowing steadily and
uniformly in a belt of limited width L parallel to the coast from nega-
tive to positive direction of y. This is a disposition favorable for the
upwelling to actually occur. Take the z-axis vertically downwards.
In a steady state which is attained after a sufficiently long time since
the wind began to blow constantly, the motion of water will be inde-
pendent of y. This means that all the vertical and horizontal compo-
nents of the currents can be determined as functions of x and z only.
Moreover, the surface of the sea will not be a plane, but have a slope
in the x-direction. In such a case, the hydrodynamical equations of
motion of sea water are, after several reasonable simplifications,
A, 0?u A, 07u ; 0g
+ 2 — — 0
Pox? =e aes © SIN gv Sas
A, 37u A, Ow ;
set —— — 2 sin gu = 0
PROX Py Oz (1)
where uw and v are the horizontal components of the current velocity
in the x and y directions, £ the surface elevation depending on x only,
P the density, A, and A, the coefficients of vertical and horizontal mix-
ing, of sea water, © the angular velosity of the Earth and ¢ the geographic
latitude. In addition to these, we have the equation of continuity in
the form:
+ a0 (2)
Ox OZ
where w is the vertical component of currents and represents the intensity
of the upwelling, and because duv/cy = 0.
Suppose the wind blows in the positive direction of y in a belt
between the coast x = 0 and x = L. The wind velocity may vary in
the offshore or x-direction. The conditions to be satisfied on the sur-
face of the sea are therefore at
Cu
— A =) e
” Oz (3)
can eee ~ =, for? =*2SL
=0 forL 2), the expression
(19) can be given very accurately by
W = agy (A) Be ay
(2 a0 2772)u sin bD;,
i7D, 1 i 1 — cos (AL/D,) Opera ie
JL NE x (21)
Now we have, for the vertical component w,
mw =O sep = Oe S10 (22)
since there can be no vertical motion on the surface and bottom of the
sea. Integrating (2) with respect to z from the surface down to the
bottom, we have
3 {: + a
ea |) YC S00 |\ SS
Ox 0 z—0
h
This means that the integral Sua
is independent of x, or therefore a constant. But as this integral must
vanish directly on the coast or at x = 0, we must have
bh
uae = () (23)
0
always. Integrating (21) with respect to z from 0 to k and equating
the real part of the resulting equation to zero, we have
() ’ x7/ pw 1] — cos (AL /D,)
Hs
? le Qi he A
BC pee? ) tee (24)
This determines the relation between the wind stress 7 and slope of the
sea surface induced by the former. Substitution of (24) in (21) gives
u,, and v,. The substitutions of u,, v, and y(A) thus obtained into
(10), (11) and (12) give wu, v and the surface slope 0¢/0é. The vertical
velocity w can be derived from the equation of continuity (2) as
562 EIGHTH PACIFIC SCIENCE CONGRESS
Z
pent ac 0) i) udz (25)
Ox 0 : 2 ;
3. UPWELLING IN A DEEP SEA
When the sea is sufficiently deep and the ratio h/D, increased in-
definitely, we have from (24)
yO) 0 (26)
and (21) becomes
17D Ae = cosy (NIE/ DD)
SS a ea led
YS ee oy ee (27)
N/ NEw nr
Then we have
ey | eae ale
U(x,z%) = po sin om (A, 2) R (A, x) dr (28)
Q
mn 2rr co
acd f N (2) R (a,x) da (29)
0
D co
2 2ar mae NEE, 2) Saco (30)
ce) po sin ol Di .
where
Ov cos(Oz Dy we sin(Oz 7D) ia.
vie rn
P? = Q?
P DN Oo 1D),
INI Os, 2) = pa ee i a Ane) pe ern ie (32)
P? — (OP
LL(A,2) = if
2PQ | cos (Qz/D,)e-P2/D, — I } + 2 — Q* sin (Qz/D,Je P42.
(P+ OP (33)
18 (A, x) ==" Sin) (ax/D,)} ita eee (34)
S(A, x) = cos (Ax/Dy){1 — cos (AL/D,) } (35)
and P and Q are the real and imaginary part of \/A2 + 272: whose
expressions are given by (20).
These results show that, by the effect of the wind blowing parallel
to the coast, we can expect a vertical circulation in the plane perpen-
THEORY OF UPWELLING AND COASTAL CURRENTS 563
[ne
dicular to the coast in addition to a coastal current parallel to the
direction of the wind. The vertical component of this circulation evi-
dently represents the upwelling.
From the expressions (28), (29) and (30) for u, v and w, it can be
expected that the horizontal velocity of the water in this process is
approximately D,/D, or \/A,/A, times as large as the vertical velocity.
This result will be very useful in estimating the approximate speed of
upwelling. But this kind of vertical circulation can be noticed best
in the case of a very deep sea where there is very little current produced
by the slope of the surface of the sea.
If we define a function ¥ (x,z) as
(oa)
GR f Srl gee eos ULE Ne NP
poe. A/S 2
(86)
we can show that this is the stream function in the plane perpendicular
to the coast and u and w are given by
ov ow
(Dea ries : v= — 3
OZ Ox (37)
so that any curve
W (x,z) = constant
represents a stream line.
4. A NUMERICAL EXAMPLE
So far the author has elucidated the process of upwelling in a quan-
titative manner and obtained the expressions representing the motion
of water produced by a wind blowing parallel to the coast in a belt of
finite width. The stream-function w (x,z) can be computed from the
formula (36) for any distance x/D, and for any depth z/D, below the
sea surface where D, and D, are the distance and depth specifying the
intensity of the horizontal and vertical mixing respectively. The result
of computation of the stream function is given in the Table I and illus-
trated by the diagram in Figure 2. ‘The unit is given by
canme 10-+
po sin. cr)
From the table and diagram it can be easily shown that the vertical
circulation is most strongly developed close to the coast and in the upper
layers of the sea directly below the surface swept by the wind. An in-
564 EIGHTH PACIFIC SCIENCE CONGRESS
tense upwelling can be seen in the belt within 0.5D, from the coast-line
and the stream-lines go down gradually outside the wind zone. This
means that beyond the wind zone there occurs the process of sinking.
The fact that the expressions for the velocity components all in-
clude sin ¢ in the denominator shows that the lower the latitude the
more intense will be the process of upwelling. Perhaps the strong
upwelling off the Peruvian coast may be ascribed to this theoretical
result. ae
It will be interesting and useful to compute the magnitude of the
off-shore currents and the velocity of upwelling from the stream-function
given by (36) and to compare them with the values formerly estimated
from various sources.
It is of course not easy to estimate the magnitude of the coefficients
of mixing. ‘The vertical mixing coefficient may be estimated at some-
thing like 1000 c.g.s. If we adopt this value, D, is about 162 meters
for a latitude of 30° N. ‘To estimate A, is even more difficult. But
actual oceanographic observations show that 4,/A, = 10° approximately.
This means that D, is just about 1000 times as large as D,, cr 162 kilo-
meters. Furthermore, we do not know much about the width of the
coastal wind belt. In this computation, the author tentatively assumed
L = 2.0944 x D, that is, about twice as large as D,; or at 339 kilo-
meters.
It will be still more difficult to estimate the wind velocity of the
northwesterlies prevailing off the coast of Southern California in the
earlier summer months. The author took ; = 1 cg.s. ‘This corre-
sponds to a wind velocity between 5 and 6 m/s. If we consider the
upwelling off the coast of southern California and take 6 = 30° N,
we have
Se So 0 wae
From the table we can compute the average velocity between the surface
and the layer 0.2D, deep by
oie
SoeTEN) Bie volar citigs eee
po Sin db Az 0.2D,
= 3.35 cm/sec (offshore)
This is the maximum velocity of the offshore current in the layer be
tween the surface and the 32.4 meters level.
The maximum vertical velocity can be estimated in a similar way,
Viz., at
THEORY OF UPWELLING AND COASTAL CURRENTS 565
ant At 0.083
Se CG $2 108 cE Be
po sin & Ax 1 X <4D, 3.14 x 10-3 cm/sec (upward)
= Zhi) aii.
This speed of upwelling is just about 80 meters per month.
G. F. McEwen (1929) estimated the speed of upwelling off the coast
of Southern California at about 10-20 meters per month. The present
result appears to show a speed a little too high, but may be suggestive
of the order of magnitude of ascending motion in the process of up-
welling.
From the diagram in Figure 2, we can see that the water mass par-
ticipating in this process comes up from the layers from z = D, to 1.5D,
or more. If we take D, = 162 m, the layers from which the upwelled
waters originate are located somewhere around the layers 200 meters or
deeper. This also agrees with Sverdrup-Fleming’s estimation derived
from practical observations off the coast of Southern California.
5. COASTAL CURRENTS
In addition to the circulation in a vertical plane perpendicular to
the coast, we have a current parallel to the coast. The author thinks
that this will be another subject of major interest.
The model treated in this research is very simple, the winds being
assumed always to blow parallel to the coast. But it may be considered
that a certain pattern of water motion will always correspond to the
wind of any direction. ‘The investigation into this problem seems sug-
gestive of the explanation of several facts observed close to the shore
in relation to the motion of the water.
6. ACKNOWLEDGMENTS
The author hereby expresses his sincerest appreciation to Dr. Dale
F. Leipper, Head of the Department of Oceanography, Agricultural and
Mechanical College of Texas, who encouraged the author in carrying
out the present research and publishing the result during his stay in the
department. He is also much obliged to Mr. Robert O. Reid and
Dr. John T. Hurt who kindly discussed on the result.
REFERENCES
DEFANT, A. 1936. Das Kaltwasserauftriebsgebiet von der Kiiste Stidwest-
afrikas—Landerkundliche Forschung, Festschrift Norbert Krebs zur Vol-
lendung des 60, Lebensjahres dargebracht, p. 52-66.
1952. Theoretische Uberlegungen zum Phanomen des Windstaus
und des Auftriebes an ozeanischen Kiisten. Deutsche Hydrographische
Zeitschrift. Bd 5, Heft % pp. 69-80.
566 EIGHTH PACIFIC SCIENCE CONGRESS
GUNTHER, E. R. 1936. A report on oceanographical investigations in the
Peru coastal current. Discovery Repts. Vol. 13 pp. 109-275.
McEwen, G. F. 1912. The distribution of ocean temperatures along the
west coast of North America deduced from Ekman’s theory of upwelling
of cold water from the adjacent ocean depths. Internationale Revue des
Gesamten Hydrobiologie und Hydrographie. Bd 5, pp. 248-286.
1929. A mathematical theory of the vertical distribution of tem-
perature and salinity in water under the action of radiation, conduction,
evaporation, and mixing due to the resulting convection. Scripps Inst.
Oceanogr. Bull., Tech. Ser. Vol. 2, No. 6. pp. 197-306.
SVERDRUP, H. U. 19380. Some oceanographic results of the Carnegie’s work
in the Pacific—The Peruvian Current. Amer. Geophys. Union Transac-
tions, pp. 257-264.
1938. On the process of upwelling. Journal of Marine Research.
Vol. 1, pp. 155-164.
SverDRuUP, H. U.. and R. H. Fupmine. 1941. The water off the coast of
Southern California, March to July, 1937. Scripps Institution of Ocea-
nography, Bulletins. Vol. 4, pp. 261-378.
567
THEORY OF UPWELLING AND COASTAL CURRENTS
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THEORY OF UPWELLING AND COASTAL CURRENTS 569
COAST
WIND BELT
SCHEMATIC DIAGRAM OF WIND TO COAST RELATIONSHIP
OR THE DEVELOPMENT OF UPWELLING IN THE NORTHERN HEMISPHERE
FIGURE |
570 EIGHTH PACIFIC SCIENCE CONGRESS
¢ NY SK >
DISAROLE o
R SSS S> Wl
ND ZONE L
ae ae
Z=0
(SURFACE)
Z#12D,
Zz
UPWELLING AS INDUCED BY A WIND PARALLEL TO THE COAST
(ILLUSTRATED BY THE STREAMLINES IN THE VERTICAL PLANE PERPENDICULAR TO THE COAST)
FIGURE 2
80'UO-
20°0-
90'0-
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST
Bye LuLty and LAS Es Dor
Pacific Oceanographic Group, Nanaimo, B.C., Canada
In 1950 the Pacific Oceanographic Group undertook an explora-
tory investigation of the physical oceanographic conditions in the Paci-
fic Ocean within some 300 to 650 miles west of the Canadian coast
(Figure 1). Four surveys were completed, in August 1950, May 1951,
August 1951, and March 1952. ‘These included serial observations of
temperature and salinity to depths variously of 900, 1000, and 1200
metres on the several cruises. Although the four cruises were observed
in different years it is convenient in some cases to regard the data in
sequence of seasons.
STRUCTURE AND PHySICAL PROPERTIES OF THE WATER
The most conspicuous characteristic of the water structure of this
area is the presence of the distinct layers, or zones.* “These are con-
veniently illustrated by plotting the properties as functions of the loga-
rithm of depth as shown in Figure 2 (Tully, 1948, 1953). In this figure
the surface zone is defined by the logarithmic salinity-depth relation ex-
tending to about 80 metres, the lower zone by the logarithmic relation
below 180 metres, and the salicline is regarded as a transition zone be-
tween these two principal water masses. A similar but not concurrent
structure occurs in the temperature.
In winter (March 1952) the properties of the upper zone approach
vertical homogeneity due to cooling at the surface and vigorous mixing
by winter storms. At this time the temperature and salinity structure
correspond. As vernal heating progresses (May 1951) the surface waters
are warmed and a shailow thermocline develops which gradually deep-
ens and becomes more pronounced as summer progresses (August 1950,
1951). With the advent of autumn weather and storms in September,
the surface waters are cooled and the winds cause mixing to greater and
greater depths. In this process the thermocline sinks, becoming less
distinct, until late winter (March) it coincides with the salicline.
During the summer the fresh water from precipitation and land
drainage is conserved near the surface in the presence of light winds
? Tully, in his discussion of the oceanography of Alberni Inlet (1949) has used the term
‘zone’ to designate the principal layers in the water structure. This term has the advantage
of being more specific in its reference than “layer’’, which is used variously to designate hori-
zontal strata of any order.
5i1
572 EIGHTH PACIFIC SCIENCE CONGRESS
and strong thermal gradients. In the winter there is much greater pre-
cipitation but the fresh water is mixed to great depths by the violent
winter winds, which also reduce the thermal gradient.
The seasonal variation occurs only in the surface zone, and never
extends below the salicline. Thus the properties of the water at this
boundary are associated with the extreme of winter conditions. Due
to the strong salinity gradient, it is the zone of permanent stability
maximum below the depth of seasonal influence. There is always a
temperature discontinuity of some degree coincident with the salicline.
Usually there is a small negative (decreasing) temperature gradient;
however, there were positive (increasing) gradients in the northern
part of the area in 1950, and in the southern part in 1951. In some
cases these amounted to more than a degree Centigrade and were stable
in the presence of large salinity gradients.
Beneath the salicline and extending to the maximum depth sam-
pled, is the lower zone, where both the temperature and salinity gra-
dients show marked regularity. In fact they fitted the logarithmic struc-
ture suggested by Tully (1953) within the limits of observations.
As shown in Figure 3 the surface salinity is lowest at the ccast
and increases seaward throughout the area, and in all seasons. The
lowest salinities appear to be associated with Juan de Fuca Strait, and
Queen Charlotte Sound, and suggest outflows of coastal waters. The
runoff from the land is a substantial factor in reducing the salinity of
the surface zone. Even in March when the offshore region was essen-
tially homogeneous to 100 metres depth, appreciable gradients were
observed near the coast. Along Vancouver Island the local runoff is
a maximum in the winter (Pickard and McLeod, 1953). However, the
greatest runoff from the coast as a whole occurs in June, when the
large mainland rivers flood due to melting snow in the mountains.
Following these floods the fresh water influence is a maximum and
extends far offshore. More detailed investigation immediately adja-
cent to the land would undoubtedly reveal a complex series of systems,
varying with tide, as well as the local runoff and discharges from the
major drainage systems.
In the offshore region the salinity was relatively constant during
each survey, but changed significantly from summer to winter. In the
summer, the fresher waters tend to be conserved near the surface, hence
the salinity is less than in the winter when the waters are mixed to great
depth by the violent storms. In this region the vertical salinity gradient
is small at all times, but tends to be greater in summer than in winter.
The summer gradients are presumably due to the great precipitation
in this area, and are preserved under conditions of strong thermal!
stability.
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST 973
The surface temperatures observed during the four cruises are
shown in Figure 4. During the summer the water along the coast is
cold, particularly in the approaches to Juan de Fuca Strait. This cold
coastal belt corresponds to the region of fresh water influence shown
in the previous figure. The temperature of the surface zone increases to
seaward.
In August 1950 there were several clouds of warm water lying in
a band extending due south from the Queen Charlotte Islands and be-
coming warmer towards the southern limit of the area. Thus the coldest
and warmest regions were contiguous. West of the warm belt the
water became colder in all latitudes, the minimum temperatures being
similar to those in the approaches to Juan de Fuca Strait.
In August 1951 the characteristic band of cold coastal water was
again present, and the temperatures increased to seaward. However, in
the offshore regions the isotherms crossed the area essentially normal
to the coast. ‘The principal gradient instead of being east-west as in the
previous year, was practically north-south. Although the average tem-
perature was two degrees higher in 1951, the range was smaller. This
picture is a distinctly different type of situation from that observed
in the previous year.
It is interesting to note in passing that during August 1950 vast
numbers of vellela were observed throughout the entire areas of this
survey west of Longitude 130°W. Large numbers were visible at all
times, and they frequently occurred in such concentrations as to look
like great streaks of foam on the water. By the crudest of calculations
it was estimated that the number in the area between Longitude
141°W and the coast would be of the order of 10° to 101, and it is
not known how much further they extended in all directions. In
August 1951, on the other hand, when the water was warmer, not a
single specimen was observed throughout the cruise.
In winter the warmest water was along the shore, and became
colder to seaward. It appears likely that this condition is typical of
winter and spring.
The dynamic topographies of the sea surface shown in Figure 5
indicate that the currents are weak and variable. In the summer the
currents do not exceed two miles a day (4 cm./sec.). They are so sinu-
ous that there appears to be no resolution of flow in the southern
part of the area. However, there is a general tendency for water to
enter from the south and west, and leave to the north. This results
in some degree of convergence and acceleration towards the northern
limit of the area. The two August and the May surveys were made
during periods of northwest winds which oppose and retard the net
flow. The northward tendency is much stronger in the winter (March
574 EIGHTH PACIFIC SCIENCE CONGRESS
1952), attaining four miles a day (8 to 10 cm./sec.). This flow was
accelerated by southeast winds, which are dominant in winter.
In the study of the data it was found that the currents decreased
with depth to about half the surface value at 300 metres. Below this
depth there was little or no intrusion of water from the west, so that
there was only a slow northward movement.
It was considered instructive to examine the data by the method
of isentropic analysis (Rossby, 1936; Montgomery, 1938), which does
not assume gradient flow. However, it was kept in mind that the pro-
cess of vertical mixing, which would limit the validity of this ap-
proach, is likely to be strongest near the coast. The principal patterns
of flow suggested by the isentropic charts was similar to those shown by
the calculated dynamic topography, although considerable differences
in detail were overlooked. However, there was no more definition of
flow in these isentropic analyses than in the gradient studies. It was
evident that in the summer the area was dominated by eddies or very
slow indeterminate movements, with no more than a general tendency
northward.
When surface waters are carried seaward by winds from the north-
west they are replaced in part by the upwelling of deep waters along
the coast. This upwelling has been advanced by a number of authors
as an explanation of the cold saline waters found along this coast in
the upper zone, during the summer (Igelsrud et al., 1936; ‘Tully, 1938:
Pickard and McLeod, 1953) and by Sverdrup (1941), who observed simi-
lar phenomena along the California coast.
Figure 6 shows the disposition of isotherms and isosalines along
a line normal to the coast of Vancouver Island, during each of the sur-
veys. The March 1952 cruise followed a period of fairly strong varia-
ble winds which were predominantly southeast. There is no indication
of upwelling associated with these data. The other three cruises were
preceded by predominantly northwest winds, and show a distinct rise
of the isotherms and isosalines adjacent to the coast. ‘This tendency
is most marked in August 1951, when the northwest winds were most
prolonged and consistent.
In the classical example of upwelling found off California, the
offshore movement of the waters results in the accumulation of light
surface water in a narrow stream parallel to the coast, and some dis-
tance from it. Off the British Columbia coast the northwest winds
oppose the prevailing current and no coastal stream is developed. How-
ever, the offshore tendency persists and results in a degree of upwelling.
As the water upwells in summer it is diluted by coastal drainage, warmed
by insolation, and dispersed in a narrow north flowing coastwise cur-
rent which has been described by Tully (1938). ‘Vhis current loses
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST 575
water to the coastal region because of the offshore component of the
summer winds. This seaward transport is evidently greater than the
supply from runoff so that there is a degree of upwelling. This results
in a band of cold water along the coast, which would be as saline as the
California coastal water, if it were not diluted by the great summer
runoff.
In the winter the prevailing southeast winds impart an onshore
component to the motion, the light water is confined in a narrow region.
close to the coast, and the surface waters are depressed. ‘This is evi-
denced in the accumulation of low salinity warmer water along the
coast at this time. ‘The seasonal effect is noticeable here in that the
coastal water, although warmer than that to seaward, is colder than
during the summer.
ORIGINS AND CIRCULATION OF THE WATER
The general circulation system of the north Pacific Ocean (Figure
7) has long been established by the Pilot Charts of the U.S. Hydrograph-
ic Office. The west wind current, called the Sub-Arctic Current by
Sverdrup (1942) is the wind driven drift of surface water eastward
across the Pacific Ocean between Latitudes 40° and 50°N. As this cur-
rent approaches the coast of North America it divides. Part turns north
to form the Alaska Gyral, and part turns south to form the California
Current.
The Marine Lite Research Program from Scripps Institution of
Oceanography has been studying the California Current in a series of
near-monthly cruises since 1949. Fortunately their Cruise 17 coincided
with the August 1950 survey and it was possible to combine the dynamic
charts as shown in Figure 8. This chart covers an enormous area, and
is the first dynamic picture of the current system off the North Ameri-
can coast. It is a spectacular confirmation of the previous conclusions
from the Pilot Charts.
It is regretted that the other surveys by both agencies were not co-
ordinated more closely so that a seasonal, and annual series of such
diagrams could have been prepared. However, this example shows the
position of the area of the present studies in relation to the whole cur-
rent system, and allows the interpretation of the observations on a
broad basis.
Evidently the area off the coast of British Columbia is in the region
of the divergence. Because of this, it is a region of eddies, or slow
and indefinite currents. Furthermore, it is extremely sensitive to small
changes in the route of the trans-ocean current. It may be subject to
576 KIGHTH PACIFIC SCIENCE CONGRESS
northern or southern flow as the point of division of the major current
shifts south or north.
Previous studies in the northeast Pacific Ocean have examined
small parts of the system. ‘The U.S.S. Bushnell (Sverdrup et al., 1942)
crossed the Sub-Arctic Current from the Aleutians to Hawaii. U.S.S.
Oglala (Goodman and Thompson, 1940) crossed from the Aleutians
to Juan de Fuca Strait. The International Salmon Commission (Mc-
Ewen e¢ al., 1930) examined three sections normal to the coast in the
Gulf of Alaska. Each of these studies shows part of the general picture.
When they are considered together it is evident that there is a con-
tinuous circulation of low salinity coastal water, in a counterclockwise
direction all around the Gulf. Part of this stream is dissipated through
the Aleutian Islands into the Bering Sea and the remainder moves
southwards to join the continent-bound Sub-Arctic Current. The low
salinity surface zone water found throughout the Gulf of Alaska is pro-
bably due to the conservation and re-circulation of a substantial part
of the coastal water, as well as to the high precipitation associated with
the semi-permanent Aleutian low pressure area.
Thompson and Van Cleve (1936) have deduced from drift bottle
experiments that in March 1932 the division of the Sub-Arctic Current
to form the Alaska Gyral and the California Current occurred well
south of Latitude 47°N. They point out that this conforms to the la-
titude of the division between residual winds, with a northerly and
southerly component, as calculated from the Pilot Charts. The result-
ing current along the British Columbia coast in the winter agrees well
with this.
From drift bottle experiments during the summer of 1931, Thomp-
son and Van Cleve concluded that the division of the currents occurred
further north at Latitude 50°N, which again agrees well with the divi-
sion of winds deduced from the Pilot Charts. This conclusion is also
supported by Tully’s (1938) examination of the waters within 100 miles
of Vancouver Island in 1936. ‘These indicated that the general flow was
southeasterly and suggest that the division of the great current was
north of Latitude 50°N in that summer. ‘These early observations ap-
pear to contradict the findings of the 1950 and 1951 studies where the
general movement appears to be northward. However, when these are
viewed as part of the overall picture (Figure 8) it is evident that there
is no contradiction. The southward movement occurs near the coast of
Vancouver Island, while the northward tendency is further offshore,
and becomes stronger to northward.
These earlier studies are not complete enough to describe the
character and location of the great divergence with any precision, and
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST 577
it cannot be determined whether there are significant differences be-
tween them and the present surveys.
However, it is evident that there are important differences be-
tween the conditions observed in 1950 and 1951 (Figure 5). The cal-
culated gradients and isentropic analyses suggest that the division of
the Sub-Arctic Current was further south in 1951. An attempt was
made to relate this difference with the atmospheric pressure systems
in the area. However, these showed that the division between the winds
with a southerly component and those with a residual northerly com-
ponent was further south in 1950. Thus the differences between these
two years observations are not immediately apparent in the wind fields.
Considering the character and magnitude of the system (Figure 8)
it may be anticipated that the division of currents will shift north and
south by several degrees of latitude from year to year. Such changes
are small, but their effect is enormous in the strategic area off the Bri-
tish Columbia coast. It cannot be said that the early data showing a
southward flow near the shore are inconsistent with the present data
indicating a northward movement further offshore, or that the change
of character of the currents and properties from year to year are ano-
malous. The present problem is to determine the cause, sequence, and
nature of these changes.
REFERENCES
GOODMAN, J. and T. G. THOMPSON. Characteristics of the waters in sections
from Dutch Harbor, Alaska to the Strait of Juan de Fuca, and from
the Strait cf Juan de Fuca to Hawaii. Univ. of Wash. Publ. in Ocea-
nography, 3 (8) 81-103, 1940.
IGELSRUD, I., R. J. ROBINSON and T. G. THOMPSON. The distribution of phos-
phates in the sea water of the northeast Pacific. Univ. of Wash. Pudl. in
Oceanography, 3 (1) 1-34, 19386.
McEwEn, G. F., T. G. THOMPSON and R. VAN CLEVE. Hydrographic sections
and calculated currents in the Gulf of Alaska, 1927 and 1928. Rep. Int.
Fish. Comm., 4, 86, 19380.
MoNTGOMERY, R. B. Circulation in the upper layers of the southern north
Atlantic deduced with use of isentropic analysis. Papers in Phys. Ocea-
nog. and Meteorol. Wood’s Hole Oceanog. Inst., VI, 2, 55, 1938.
PICKARD, G. L. and D. C. McLrop. The seasonal variation of the tempera-
ture and salinity of the surface waters of the British Columbia coast.
Journ. Fish. Res. Bd. Can., 10 (8) 1958.
RossBy, C. G. Dynamics of steady ocean currents in the light of experimental
fluid mechanics. Papers in Phys. Oceanog. and Meteorol. Wood’s Hole
Oceanog. Inst., 5, 1, 1936.
Scripps Institution of Oceanography. Physical and chemical data, Cruise 17,
Marine Life Research Program, MS. 51-32, 1951.
SverDRuP, H. U. and R. H. FLEMING. The waters off the coast of southern
California. March to July, 19387. Bull. Scripps Inst. Oceanog., 4, 10,
261-378, 1941.
578 EIGHTH PACIFIC SCIENCE CONGRESS
SVERDRUP, H. U., W. M. JOHNSON and R. H. FLEMING. The oceans, their
physics, chemistry, and general biology. Prentice-Hall Inc. New York,
1087, 1942.
THOMPSON, W. F. and R. VAN CLEVE. Life history of the Pacific halibut.
Rept. Int. Fish. Comm., 9, 184, 19386.
TuLLy, J. P. Some relations between meteorology and coast gradient cur-
rents off the Pacific Coast of North America. Trans. Amer. Geophys.
Union, 19th Annual Rept., 1, 183-187, 19388.
TULLY, J. P. Notes on the behaviour of fresh water entering the sea. Proc.
Seventh Pac. Sc. Cong., Wellington, N.Z. 1949 (1952). MS. Rept. Pacific
Oceanographic Group, Nanaimo, B.C., 1948.
TuLty, J. P. Some characteristics of seawater structure. Proc. Eighth Pac.
Se. Cong., Manila, 1958. MS. Rept. Pacific Oceanographic Group, Na-
naimo, B.C., 1953.
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST a7T9
LIST OP FELCURES
Fig. 1.—Chart of the offshore waters of the Canadian Pacific Coast showing
the courses sailed, and the stations occupied in May and August,
1951. Observations were made along approximately the same lines
in the other cruises, although the arrangement and numeration of
the stations were different.
Fic. 2—Examples of the characteristic temperature and salinity structure
in the offshore region, off the Pacific Coast of Canada, at Latitude
50°N, Longitude 1385°W (c.f. Figure 1).
Fic. 3.—Surface salinity observed off the Pacific Coast of Canada.
Fic. 4.—Surface temperatures observed off the Pacific Coast of Canada.
Fic. 5.—Calculated geopotential topography of the sea surface (anomaly of
dynamic height, metres) and implied gradient currents. Arrows in-
dicate the direction of flow. The inset diagram shows the current
speed in relation to the distance between isobars.
Fic. 6.—Structure of the water off the Pacific Coast of Canada. Vertical
sections showing the distribution of temperature (°C light lines) and
salinity (S °/,, heavy lines) as observed on line A, normal to the
coast of Vancouver Island during each o fthe four cruises. The
location of the section is shown in Figure 1.
Fic. 7.—-Schematic diagram of the surface zone circulation in the northeast
Pacific Ocean.
Fic. 8—Anomaly of dynamic height (metres) from the August, 1950 survey
of the Pacific Oceanographic Group, and Cruise 17 of the Marine
Life Research Program (Scripps, 1951).
DR
.
ee
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SURFACE WATERS
s*c
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OUND
FIGURE 1
TERPLRATURE SCALE
= Lh
is
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Stotion 39
AUGUST ___1950
Station C8
MAY _1951
Sol/nity
Temperature
Upper Lone sper Zone
100 F rhermoctine
Lower
Winter
Thermocline
no
fone lower Zone
LiL
ava
Stotion Station C8
AUGUST MARCH 1952
Temperature
Upper Lore Upper Zore
Temperature
Winter
Thermocline
lower Zone
3
SALINITY SCALE
FIGURE 2
5&2 EIGHTH PACIFIC SCIENCE CONGRESS
MAY
+ AuGUST 195!
MARCH 1952
FIGURE
° us 30°
CEN.
120 > age)
ZIV ES
. we ass
AUGUST 1951
FIGURE 4
(J)
MAY ISI
ns
MARCH 1952
SURFACE WATERS OFF THE CANADIAN PACIFIC COAST 583
z061 HOUVH \ Is6l 4snony
isst AVA
1000 KLM 800 200 KLu oO 1c0O KLM €00 600 200 mt OO
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DISTANCE FROM COAST DISTANCE FROM COAST
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MARCH 1952
Ling A AUGUST I95! a
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FIGURE 6
584 EIGHTH PACIFIC SCIENCE CONGRESS
SUBARCTIC
CURRENT
2 TO CALIFORNIA
CURRENT
—_
NORTH PACIFIC
Hs
dL
CANADA
FIGURE 8
CIRCULATION NEAR THE WASHINGTON COAST *
By Ciirrorp A. BARNES and RoBERT G. PAQUETTE
Department of Oceanography
University of Washington
Seattle, Washington, U.S.A.
INTRODUCTION
The area covered in this paper is a section of the Northeast Pacific
Ocean bordering the West Coast of North America between the paral-
Jels of 44° and 51° North and extending 600 miles seaward (Fig. 1).
The coast is mountainous and contributes considerable runoff to the sea
from heavy precipitation in winter and the melting of the snow in early
summer. ‘Two concentrated sources of fresh water are the Strait of
Juan de Fuca and the Columbia River, which drain large inland areas.
The Strait differs markedly from the river in that it is the mouth of a
large tidal basin and is deeper than 100 fathoms for a considerable dis-
tance inshore. As a result of the tidal action, its effluent has been
considerably altered by mixing with the cold deeper water.
The continental shelf, as measured by the 100-fathom contour, ex-
tends about 40 miles offshore near the Strait of Juan de Fuca and nar-
rows to about 20 miles both northward and southward. Beyond the
slope, depths increase gradually to about 2000 fathoms. A number of
‘seamounts rise from this deeper water, but the bathymetry of only a few
has been worked out in any detail.
The climate of the region is predominantly maritime with prevail-
ing southwesterly onshore winds accompanied by heavy precipitation
from autumn to spring. In summer considerable air flow is from the
northwest and north and little precipitation occurs.
The circulation of the Northeast Pacific is predominantly clock-
wise to latitude 40° North, giving way to counterclockwise south of 50°
North (Sverdrup, Johnson and Fleming, 1946). The colder water along
the northern periphery of the main easterly drift in mid-ocean, the so-
called Aleutian or Subarctic Current, splits in all ill-defined zone well
seaward from the coast near 45° North, both orientation and position
of the zone of divergence varying with the season. The northerly arm,
the Alaska Current, recurves through the Gulf of Alaska; and the south-
erly arm, the California Current, sets south well offshore at lower lati-
* Contribution number 194 from the Department of Oceanography of the University of
Washington. Technical Report No. 17, University of Washington and Office of Naval Research,
Contract N8onr-520/III, Project NR 083-012, and Contract Nonr-477(01), Project NR 083-072.
585
O36 EIGHTH PACIFIC SCIENCE CONGRESS
tudes. Oif the Washington and Oregon Coasts in winter, the Davidson
Current feeds water northward inshore. The area studied, being an
area of divergence, is characterized by weak and poorly defined currents
which are easily influenced by temporally changing wind patterns and
local bathymetric irregularities.
The measurements to be reported in this paper were carried out
with the research vessel M. V. BROWN BEAR during seven offshore
cruises in the spring and summer months of 1952 and 1953. Because
of the anticipated variations of currents with time, determinations of
circulation patterns by dynamic topographies were supplemented by use
of the Geomagnetic-Electro-Kinetograph (G.E.K.). It was quickly dis-
covered that the latter instrument was measuring currents (or effects)
very much greater than those from dynamic topographies, and showing
a rotary variation with time. In recent cruises therefore, several time
studies have been made to discover the nature of the rotary variations.
Further evidence of the reality of the rotary variations was ob-
tained by direct current measurements from an anchor station on Cobb
Seamount, a seamount rising very sharply from 1500 fathoms depth to
within 16 fathoms of the surface, and located approximately 270 miles
west of the Washington Coast (46°-45.5’N, 130°-46.3’W). ‘The results
from two such time studies are presented in some detail.
Another sphere of activity has been a detailed investigation of the
outflows of the Strait of Juan de Fuca and the Columbia River, par-
ticularly the latter. “The outflow of the Columbia has been traced for
over 200 miles seaward. The position and structure of this long plume
of less saline water is of interest as an indicator of offshore circulation
and mixing, and because of the possible influence it may exert in di-
recting the salmon which migrate to and from the river.
The circulation near the coast of Vancouver Island and the mouth
of the Strait of Juan de Fuca has been discussed by Tully (1938, 1941)
on the basis of salinities and temperatures measured near the coast,
often in shallow water. ‘These measurements as well as those of Mar-
mer (1926) made from Swiftsure Lightship establish the direction of
outflow of the Strait of Juan de Fuca as northwestward, very close and
parallel to the coast of Vancouver Island. Tully further shows the
accumulation of fresh water along the coast due to the prevailing south-
westerly winds in spring and early summer, with a gradual transition
to a condition of upwelling in a narrow band along the coast under
influence of the northerly winds of late summer. He interprets the
resulting dynamic topographies as representing northwesterly flows close
to the coast in early summer and a reversal in direction in late summer.
The latter flow, however, is overcome by the generally northwesterly
CIRCULATION NEAR THE WASHINGTON COAST D387
outflow of the Strait of Juan de Fuca near the mouth of the Strait.
Similar conclusions as to the seasonal shift in currents were reached by
Thompson and Van Cleve (1956) from drift bottle experiments com-
menced about 80 miles off the Canadian Coast. These authors also
relate the change in direction of flow during the summer to a change
in wind pattern. Some dynamic sections along the coasts of Washing-
ton and Oregon are presented by Sands (1937), but these are too few
in number and too close to shore to correlate with the present work.
Farther offshore, the circulation off the Canadian Coast has been
studied by Doe (1952) and Goodman and Thompson (1940) in two
sections, from the Strait of Juan de Fuca to Dutch Harbor, and from the
Strait of Juan de Fuca to Hawaii. Still farther offshore, the Carnegie
Cruise VII (Fleming, 1945) established the gross structure of the east-
ward flowing Aleutian Current and the beginning of its separation into
southeasterly and northeasterly branches. ‘Iwo or more sections have
also been made by Scripps Institution of Oceanography, the U. S. Fish
and Wildlife Service, and the U. S. Navy Electronics Laboratory, but
the results are unpublished. ‘Yo the south, Scripps Institution of Ocea-
nography have studied the coastal currents very intensively and their
cruises have occasionally come as far north as the Columbia River.
Thus the details of the circulation near the Washington Coast are little
known.
With respect to the G.E.K., as used in areas of weak and poorly
defined currents such as this, there is little published. The interpreta-
tion of the results as currents is in some question, as is the “K’’ factor.
The apparently rotary current changes observed, although indicated by
von Arx (1950), have not been carefully analyzed, probably because in
areas Of higli currents they are relatively less important. Oceanogra-
phers at Scripps Institution of Oceanography are known to be working on
this problem. For analysis of the rotary current changes in the deep
sea, One must turn to the direct measurements made from anchored
vessels, the BLAKE in West Indian waters (Pillsbury, 1891), the
MICHAEL SARS (Helland-Hansen, 1930), the METEOR (Defant, 1932),
the ALTAIR (Defant, 1940), and the ARMAUER HANSEN (Ekman,
1953). In all of these, the uncertainties due to the motion of the an-
chored vessels weaken the validity of the conclusions. However, rotary
current changes do occur and these changes apparently contain com-
ponents of tidal and inertial periods as well as random fluctuations.
The existence of rotary currents of tidal period in shallower water is
well established, and Gustafson and Kullenberg (1936) have demon-
strated an excellent example of inertial rotations in the Baltic.
588 EIGHTH PACIFIC SCIENCE CONGRESS
WATER PROPERTIES AND CIRCULATION
As others have suggested, the horizontal gradients of temperature
and salinity may be generalized in two representations, one for spring
and early summer and one for late summer. ‘The winter conditions
have not been studied. Figures 2 and 3 show the horizontal distribu-
tion of surface temperature and surface salinity in April-May, 1953, the
data having been smoothed to eliminate local fluctuations. ‘The piling
up of warm surface water along the coast of Vancouver Island is evident.
Figures 4 and 5 show the conditions in July 1952. Here the break-
down of spring conditions is just beginning to appear. The water
which earlier increased in temperature essentially up to the coast is now
showing a wide band of somewhat cooler water near the coast. The
effect is more marked if vertical sections of temperature are plotted,
demonstrating the decrease in thickness of the surface water layer on
approaching the coast. Close to the mouth of the Strait of Juan de
Fuca, the effect is accentuated at the surface probably because of the
mixing processes of tidal flow as well as the tendency of upwelling
deeper water to appear far within the Strait.
Figures 6 and 7 (smoothed somewhat) show the conditions in Sep-
tember 1953, farther south. Although not completely comparable with
the above data because of the different areas covered, there is still sur-
ficial evidence of upwelling in the region near the mouth of the Strait
of Juan de Fuca. Along the Washington Coast south of the Strait, the
subsurface temperature structure indicates the presence of upwelling
which, however, does not reach the surface because of a blanketing layer
of less saline water. ‘This is especially so in the vicinity of the Colum-
bia River mouth where the surface waters flowing seaward are rapidly
replaced by river effluent. Along the Oregon Coast south of the Colum-
bia, low temperatures characteristic of upwelling are again apparent at
the surface.
Figures 6 and 7 also show the first results of a detailed study of
the Columbia River outflow. The plume of water having a salinity
less than 32.0°/,, is seen to extend over 200 miles to the southwest.
Associated with the lower salinity is a somewhat higher temperature.
The position of the wake stream is in itself evidence of the generally
southerly set of the currents in this region during the summer. At the
velocities indicated by the dynamic topography for the general area,
the time required for the water to travel to the outer limits of the 32°/,,,
isosal is of the order of one to two months, and hence the position of
this limit establishes a minimum value for the integrated currents for
at least this period.
CIRCULATION NEAR THE WASHINGTON COAST 589
The processes of mixing in the wake stream have not yet been
examined. However, there is some interest attached to the abrupt
change in salinity gradient seaward of the 31.0°/,, isosal. In essentially
all of the area between this and the next isosal, the surface salinities
are greater than 31.5°/,, and mostly greater than 31.7°/,9.
The dynamic topographies within 300 miles of the coast have been
quite consistent in all the cruises analyzed. Since only Cruise No. 7 in
July 1952, went as far offshore as 600 miles, data from this cruise are
combined with a composite of all the others to obtain a generalized
diagram for the area which is presented as Figure 8. The curves south
of 46°-30’ are based principally upon data from Cruise No. 9 in early
September 1952.
Appearing generally in all cruises are the lower dynamic heights
to the west of about 130°W, corresponding to northerly or northeasterly
flows of 5 cm/sec or less. Some changes in gradient occur in different
months but the general picture is little altered except that the contours
seem to tend more nearly northward in the early summer, as would be
expected from the meteorological conditions. Also appearing in all the
data is evidence for a deflection southward of northeasterly flowing
streamlines in the area between 128° and 130°Wand 47° to 49°-30’N.
The data of Cruise No. 9 indicate that this flow continues southward
along the Washington Coast and is probably responsible for carrying the
Columbia River water southward. ‘These results are consistent with
those of Doe (1952).
G.E.K. RESULTS AND TIME STUDIES
Early in the investigations, it was discovered that apparent cur-
rents measured hourly by means of the G.E.K. along a cruise track
showed continual changes in direction and magnitude, suggesting the
rotary changes of tidal period observed at lightships. “These currents
typically had peak values of 15-20 cm/sec and occasionally as high as
35 cm/sec, the correction factor “K” for the G.E.K. being taken as
unity. To be contrasted with these are the velocities below 5 cm/sec,
determined from the dynamic heights. Tidal periods could be found
in the data by harmonic analysis, but the amplitudes were only about
one-fifth as great as the observed peaks. Later it was discovered that
inertial periods were present, with amplitudes of the same magnitude
or somewhat greater than those of tidal period. The inertial period
in this area is approximately 16 hours. The harmonic analyses of these
data were interpreted with some reservations due to the fact that the
ship was rapidly changing position and to the evident existence of ap-
parently random fluctuations of considerable magnitude.
590 EIGHTH PACIFIC SCIENCE CONGRESS
In order to derive the residual non-fluctuating currents in this
situation, the data have been calculated as 48-hour running means, 48
hours being the least common multiple of 16 and 12 hours. If tidal
and inertial constituents are present, they should disappear in the
averages together with the greater part of those of shorter and random
periods. This is admittedly a rather brutal treatment, as any fluctua-
tions in the residual current are severely smoothed thereby. However,
it has served for the preliminary investigations.
A serious disadvantage is the fact that the ends of a continuous
series of observations may be approached within only 24 hours by aver-
aged results, and hence any lengthy break in continuity of the data
may leave large gaps in the results. “Twenty-four hour groupings also
have been tried and are found to remove most of the fluctuations and
leave smaller gaps. It is preferred to use 48-hour means where possible,
however, since the results will be less ambiguous.
The results of such a treatment to the data of Cruise No. 7 are
shown in Figure 9. The large gap in the data on the northern leg of
the cruise is due to the break in continuity occasioned by a short storm.
Twenty-four hour means, however, show the residual currents setting
south to southwest throughout most of the northern leg, with velocities
of the order of 5 to 8 cm/sec. A comparison with Figure 8 shows some
similarity of G.E.K. means to the dynamic heights along 48°-30’N but
none whatsoever along 50°-30’N. ‘The current pattern is also internally
inconsistent, requiring the existence of a region of convergence within
the area surveyed, an improbable situation. It appears evident therefore
that the G.E.K., in this region, does not always measure the long-term
average flows associated with the distribution of mass. ‘The converse
might be true in regions where stronger currents are found.
It is postulated therefore that the currents measured are shallow
wind-driven currents of short duration. To test this hypothesis, average
wind vectors have been plotted along the course. ‘There is reasonable
correspondence along 48°-30’, assuming the resulting flow to be 45°
to the right of the wind and lagging it by a few hours. In the northwest
corner of the survey, there appears to be an inconsistency. However,
the northwest storm which appeared two days later at about 130°W
longitude may already have been driving water well ahead of it. Along
50°-30’, the agreement with 24-hour average currents (not shown) is
good.
These results showed the necessity of making time studies with the
G.E.K. The first studies begun in June 1952, were about one day in
length and were made by steaming back and forth over an 8-to-16-mile
course, obtaining G.E.K. fixes enroute. Hydrographic stations to 1,000
CIRCULATION NEAR THE WASHINGTON COAST 591
meters of depth were occupied at intervals of 2 to 12 hours in the
several experiments in an attempt to correlate the results with the
dynamic heights. Rotary changes in current direction were readily
demonstrated, but twenty-four-hour periods are too short for effective
harmonic analysis. “Two experiments of 3 to 4 days’ duration were
therefore made in June and August 1953, Cruises No. 29 and 31, re-
spectively.
In Cruise No. 29, the ship steamed backward and forward two
hours’ run on reciprocal headings, taking G.E.K. fixes every hour to-
gether with other data. Positions were fixed frequently by loran, and
hydrographic stations were occupied about every 12 hours. Some fail-
ures in equipment being used for corollary measurements caused several
undesirably large gaps in the data, but the results are only a little less
consistent than those to be presented below.
In Cruise No. 31 the cruising plan was modified, as suggested by
Mr. Joseph Reid of Scripps Institution of Oceanography, so that the
ship steamed squares on the cardinal compass headings, each side being
approximately 7 minutes’ run. Thus a fix is obtained every 7 minutes,
there being some interdependence in the measurements because each
datum enters into two fixes and two zero determinations. Reid has
directed experiments of this type in which he has simultaneously fol-
lowed a freely drifting buoy (personal communication). An attempt
to do this with an improvised buoy and drag was abandoned after the
buoy lost its drag and was itself nearly lost at night during a radar
failure.
The results of this experiment have been expressed as north and
east components of velocity and are presented in Figure 10. K has been
assumed to be unity and corrections have been made for electrode
droop. The results are surprisingly consistent and have given rise to
a renewed belief in the reality of G.E.K. measurements. ‘The 16-hour
imertial period is evident by visual inspection. Much of the distortion
is due to other components, principally the semidiurnal. Some smooth-
ing has been practiced but there is difficulty in deciding which fluctua-
tions may be real and which due to experimental uncertainty. Due to
the interdependence of separate fixes, errors often appear symmetrically
in alternate or adjacent points. Moreover, in some cases the record
can not be interpreted more accurately than several tenths of a millivolt.
In correlation with this experiment, an anchor station was occupied
for the preceding three and one-half days atop Cobb Seamount (see
Fig. 8). Here currents were measured at a depth of 20 meters with
an Ekman current meter every 30 minutes, and temperature structures
were measured hourly by bathythermograph. Bathythermograms were
592 EIGHTH PACIFIC SCIENCE CONGRESS
also obtained hourly during the time study with the G.E.K. Three
hydrographic stations were occupied at corners of a 30-mile square about
the seamount to obtain dynamic heights for comparison. The time
study with the G.E.K. was performed in depths ranging from 1,500 to
600 fathoms and between 30 and 15 miles northwest of the seamount.
The ship drifted south during the period.
The direct current measurements also show rotary changes contain-
ing tidal and inertial components. The basic periods are less well
defined because of the motions of the ship, but these motions are small
compared to those of a ship anchored in deep water. It is assumed in
these two experiments that there should be some similarity in the cur-
rents on a sharp isolated seamount to those in the adjacent deep water.
On the other hand, considerable distortion near the seamount would
not be surprising.
The results of harmonic analysis are given in Table I, for both
the direct measurements and the G.E.K. Only the 16- and 12-hour com-
ponents are considered of primary importance, but the higher har-
monics are presented to suggest the magnitude of the amplitudes which
could result from random data in a series of this length. The contribu-
tion of each constituent is assumed to be expressed in the form
V, = V, cos (6 — x3)
Ue = V..cos (6 — x2)
where v, and v, are the instantaneous values of the north and east com-
ponents of velocity, V, and V, are the corresponding amplitudes, @ is
the time angle of the constituent and «x, and «x, are the local epochs,
the negative of the conventional phase angle, the origin of time being
the time of local lunar transit on the first day of the anchor station.
If x2-x, expressed as an angle less than 180° is positive, rotation
of the current vector with time is clockwise. In particular, 1f «.-«,
= 96° and V, = V,, the current hodogram for the constituent is a
circle. Theoretically, circular changes are to be expected in the inertial
component and generally elliptical changes in the tidal component.
It is evident that most of the motion is accounted for by inertial
and semidiurnal constituents, the former preponderating. The diurnal
constituent is probably of significant magnitude, but the others are
questionable. The phase difference between north and east components
in these three constituents corresponds to clockwise rotations, as would
be expected from the deflecting force of the earth’s rotation. In the
inertial constituent, it is very nearly 90° for both the direct measure-
ments and the G.E.K. In the G.E.K. results, the two amplitudes are es-
sentially the same, which satisfies the condition for circular rotation.
Further deductions from the phase relations will be attempted at a
CIRCULATION NEAR THE WASHINGTON COAST 593
later date. The amplitude of the semidiurnal constituent on Cobb Sea-
mount is about 15 per cent less than the G.E.K. results, which is the
same as the change in the mean tidal range at Astoria during the two
periods. The change in the inertial component may arise from an in-
crease in average wind velocity from about 8 to 20 knots over the same
period.
The results of the time study in June 1953, are shown in Table
I]. Although the amplitudes are smaller, the relative importance of the
16- and 12-hour constituents is supported. This experiment was carried
cut at 48°-02’N, 130°-29’W; and by chance during the time study, the
ship drifted over and charted a new seamount rising to a least depth of
280 fathoms. This shallowing of the water may have had some effect
upon the G.E.K.
The possibility exists that internal waves of tidal and inertial period
give rise to the currents or effects measured by the G.E.K. This has
been investigated by a study of the bathythermograms taken to a depth
of 450 feet during the time study of Cruise No. 31. Internal waves oc-
cur with amplitudes of the order of 25 feet but with periods poorly
defined. Visual examination suggests six-hour and two-hour periods
rather than those of twelve or sixteen hours. It is felt therefore that
these internal waves are not a determining influence on the G.E.K.
results, but that they possibly account for some of the aberrations and
short-period constituents.
In Table III, the average residual current calculated from the three
time studies is compared with the dynamic topographies and with the
approximate drift of the ship as determined by deviations from the
courses run, measured by loran fixes. In Cruise No. 29, the G.E.K. com-
pares well with the drift of the ship but not with the dynamic topo-
graphies. This was in a period of light winds in which the ship might
be expected to move with the water. In Cruise No. 31, there is little
agreement, possibly because the winds averaged 20 knots from the north.
However, the direct current measurements compare favorably with the
dynamic topographies close to the seamount. Farther away, the velocity
and direction derived from the topographies are extremely uncertain
and are not shown. It seems well established therefore that the rotary
changes observed by the G.E.K. in deep water have their counterpart in
the direct measurements of currents.
CONCLUSIONS AND SUMMARY
The water circulation off the coasts of Vancouver Island, Washing-
ton and Oregon in late spring and summer has been studied by means
of dynamic topographies and the G.E.K. A picture is presented which
594 EIGHTH PACIFIC SCIENCE CONGRESS
fills a previously existing gap in the information for the central area.
The relatively flat dynamic topography is especially sensitive to transient
conditions and experimental error. Nevertheless, the topographies con-
sistently show a weak northeasterly circulation at 5 cm/sec or less, part
of which is deflected southward off Vancouver Island to continue along
the coast past 45° North. ‘This circulation pattern is consistent with
previous work in the adjoining areas, and with the assumed divergence
of the Aleutian Current beginning well offshore around 45° North.
The G.E.K. has been shown to measure apparent currents which
rotate in direction and fluctuate in intensity. ‘The peak flows are of
the order of 20-35 cm/sec which is several times greater than the net
flows. The rotations contain semidiurnal and inertial constituents, the
latter predominating.
A time study in direct measurement of currents on Cobb Sea-
mount, 270 miles offshore, has been compared with a similar time study
with the G.E.K. in the adjoining deep water. Harmonic analysis of the
North and East components of velocity has produced amplitudes of
7-11 cm/sec for the semidiurnal constituents. The differences could be
almost completely accounted for by the change in phase of the moon
during the period of the measurements. The amplitudes of the inertial
constituent were 9 and 13 cm/sec in one case and 22.5 cm/sec in the
other, a difference ascribed to an abrupt change in wind velocity.
Another time study with the G.E.K. showed similar results, but smaller
amplitudes. The combined results suggest that the currents being mea-
sured by the G.E.K. are real. This conclusion is supported by the pub-
lished results of current measurements at several deep-sea anchor stations
which show similar variations.
The net currents obtained by averaging the G.E.K. results show
little correspondence with those indicated by dynamic topographies. ‘The
former probably represent short-term surface currents due to the wind,
whereas the dynamic topographies represent integrated effects over
longer periods.
in conclusion, it is suggested that progress in the interpretation
of currents in this area requires a better insight into the cause and
nature of the transient currents. The G.E.K. should be useful in these
studies, but must be further evaluated in terms of direct measurements.
LITERATURE CITED
DEFANT, A. 1982. “Die Gezeiten und innern Gezeitenwellen des Atlantischen
Ozeans,” Wiss. Ergebn. der Deutschen Atlant. Expedit. auf dem ‘Meteor’
1925-1927 7 Teil I.
CIRCULATION NEAR THE WASHINGTON COAST 595
DEFANT, A. 1940. “Die ozeanographischen Verhaltnisse wahrend der Anker-
station des ‘Altair’ am Nordrand des Hauptstromstriches des Golfstromes
nordlich der Azoren,” Ann. der Hydrog., Nov.-Betheft.
Dor, L. A. E. 1952. “Oceanographic Studies off the Canadian Pacific Coast,
1951,” Unpublished report of Pacific Oceanographic Group, Nanaimo, B.
C., August 1952.
EKMAN, V. W. 1953. “Studies on Ocean Currents. Results of a Cruise on
Board the ‘Armauer Hansen’ in 1930 under the Leadership of Bjorn
Helland-Hansen,” Geofysiske Publikasjoner 19 No. 1.
FLEMING, J. A. et al. 1945. “Scientific Results of Cruise VII of the ‘Carnegie’
during 1928-1929 under Command of Captain J. P. Ault,” Carnegie Inst.
Wash. Pub. 545, Vol. I-B.
GOODMAN, J. and T. G. THOMPSON. 1940. “Characteristics of the Waters
in Sections from Dutch Harbor, Alaska to the Strait of Juan de Fuca
and from the Strait of Juan de Fuca to Hawaii,” Univ. of Wash. Pub.
in Oceanography 3, No. 3 (1940).
GUSTAFSON, T. and B. KULLENBERG. 1936. “Untersuchungen der Traigheits-
strémungen in der Ostsee,” Sv. Hydrograf. Biolog. Komm. Skrifter, Ny
Ser. Hydr. 13, 28 pp. (1936).
HELLAND-HANSEN, B. 19380. Physical Oceanography cand Meteorology. Re-
port of the Scientific Researches of the ‘Michael Sars’ North Atlantic
Deep Sea Expedition.
Marmer, H. A. 1926. U.S. Coast and Geodetic Survey Spec. Pub. 121,
63-77 (1926).
Pituspury, J. E. 1891. U.S. Coast and Geodetic Survey Report, 1890.
SANDS, WALTER C. 1937. “Hydrodynamical Investigations off the Pacific
Coast of North America,” B. 8. Thesis, University of Washington (1937).
SVERDRUP, H. U., M. W. JOHNSON and R. H. FLEMING. 1946. The Oceans,
N. Y., Prentice-Hall (1946).
THOMPSON, W. F. and R. VAN CLEVE. 1936. “Life History of the Pacific
Halibut,” Report of the International Fisheries Commission 9 (1936).
TULLY, J. P. 1938. ‘Some Relations between Meteorology and Coast Gradient
Currents off the Pacific Coast of North America,” Trans. Am. Geophys.
Union 19, 177-182 (1988).
-——-——— 1941. “Surface Non-Tidal Currents in the Approaches of Juan
de Fuca Strait,” J. Fish. Res. Bd. Can. 5, 398-409 (1942).
EIGHTH PACIFIC SCIENCE CONGRESS
596
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CIRCULATION NEAR THE WASHINGTON COAST 597
TABLE II
HARMONIC ANALYSES OF CURRENTS BY G.E.K.
7-10 June 1953
PeRiop, Sorar Hours 24 16 | 12
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TABLE III
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DYNAMIC TOPOGRAPHIES
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CIRCULATION NEAR THE WASHINGTON COAST 605
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U. S. NAVY CONTRIBUTIONS TO THE STUDY OF
PACIFIC CIRCULATION
By JoHn LyMaAn
Division of Oceanography
U.S. Navy Hydrographic Office, Washington, D.C., U.S.A.
The U. S. Navy has participated in several different ways in the
study of Pacific circulation. The Hydrographic Office, serving as the
national repository of information submitted by cooperating observers
on merchant vessels of many different nationalities, has for half a cen-
tury collected the current observations of navigators, obtained by com-
parison of celestial fixes with dead-reckoning positions. These obser-
vations up to the year 1935, reduced to punched cards, have served as
the basic materials for the preparation of Hydrographic Office Publica-
tions Nos. 568, 569, and 570. Figure 1 is a sample of the data presented
in H. O. Pubs. No. 569 and 570, which give not only vector resultant
currents for each month for each 1° quadrangle but also the frequency
distribution of set and predominant drift for somewhat larger sub-
divisions.
Observations from 1935 to 1945 have been tabulated and are on
file at the Hydrographic Office, while records since 1945 are awaiting
punching.
Cooperating mariners in the Pacific also participate in current
studies by throwing over bottle papers (Fig. 2). Captain E. R. Johanson
of the Matson Navigation Company of San Francisco has taken an
especial interest in this subject in recent years, and his name appears
frequently in the lists of recoveries, which have been regularly reparted
in the weekly Hydrographic Bulletin. These bottle drifts, while of
course they yield no direct evidence as to the precise route travelled by
a drifting object between the points of release and recovery, -never-
theless are valuable in giving general circulation patterns and minimum
values of the set of surface currents. They are particularly useful in
forecasting drifts of wreckage and floating mines.
A study of local circulation at Guam in 1949 made by naval
authorities for planning sewer outfall locations by releasing a number
of drift bottles, yielded unexpected results when several bottles turned
up at Talaud and others in the Philippines and Japan (Hydro. Bulletin
of 7 April 1951).
609
610 EIGHTH PACIFIC SCIENCE CONGRESS
During the 1930’s the U. S. Navy occupied oceanographic stations
over a wide range of the eastern North Pacific, in connection with its
hydrographic surveying program. Although the immediate objective
was to obtain temperature and salinity values that could be used in
computing the speed of sound to correct sonic soundings, the data also
yield information on the dynamic topography. Observers from Scripps
Institution of Oceanography and from the Oceanographic Laboratories
of the University of Washington participated in most of this work, and
the data were worked up at those respective institutions. ‘Table I lists
the vessels engaged in this work.
Part of the HANNIBAL, GANNET, OGLALA, and BUSHNELL data
have been published (H. O. Pub. No. 212; Barnes and Thompson,
1938; Goodman and Thompson, 1940; Sverdrup and Staff, 1943).
During World War II the oceanographic investigations of the U. S.
Navy in the Pacific were more concerned with studies of underwater
sound than with circulation. ‘The atomic bomb tests at Bikini in 1946,
however, imposed requirements for the prediction and tracing of the
movements of radioactive water. Included in the broad oceanographic
and geophysical program of Operation CROSSROADS under the direction
of Cdr. R. R. Revelle, USNR, therefore, were several series of oceano-
graphic stations taken by a group of oceanographers under Cdr. C. A.
Barnes, USCGR, in the USS BOWDITCH and BLISH, and by another
group directed by Mr. D. F. Bumpus and LCdr. John Lyman, USNR,
in several units of Destroyer Squadron 7. ‘These results have been
discussed by Barnes, Bumpus, and Lyman (1948), and in more detail
by Han-Lee Mao and Kozo Yoshida in a forthcoming U. S. Geological
Survey professional paper.
During 1946, also, three administrative actions within the U. S.
Navy produced results of significance to the study of Pacific circulation.
One was the establishment in the Hydrographic Office of a Division
of Oceanography, headed first by Dr. R. H. Fleming, Director, and
Dr. C. A. Barnes, Deputy Director. ‘These positions are now occupied
by John Lyman and Dr. C. C. Bates, respectively. Another was the
creation of the Office of Naval Research, including an Earth Sciences
Division, headed first by Cdr. R. R. Revelle, and later by Dr. J. N.
Adkins. ‘Through contracts administered by the Office of Naval Re-
search, considerable financial support has been given to oceanographic
survey programs in the Pacific. “The SPENCER F. BAIRD, a former Army
tug, converted in 1947 to an oceanographic research vessel for use in
the Philippines Fisheries program and transferred to the U. S. Navy in
1952, is operated by Scripps Institution of Oceanography, with funds
provided by the Bureau of Ships and the Office of Naval Research.
The Navy has also helped support operations of the Scripps vessel
CONTRIBUTIONS TO THE STUDY OF PACIFIC CIRCULATION 611
HORIZON in such expeditions as Mid-Pac (1950), Northern Holiday
(1951), Shellback (1952), and Capricorn (1952-53), and of the Univer-
sity of Washington research vessel BROWN BEAR.
The third action to be mentioned was the establishment of an
oceanographic unit under Mr. E. C. LaFond at the U. S. Navy Elec-
tronics Laboratory (LaFond, 1949). In addition to studies of the Pacific
with the immediate objective of defining the sound channels or Sofar,
LaFond’s group has participated in surveys in the Antarctic (Dietz,
1948) and in the Bering Sea (LaFond, e¢ al., 1948, 1952), cooperating
in the latter area with Canadian authorities (Lesser and Buffington,
1950). Sofar cruises have been performed by the USS FIEBERLING
(Holtsmark, 1949) and SERRANO (Anderson, 1950); and the EPCE(R)
854 has also carried out similar work.
In addition to the data contained in the publications already cited,
most of the observations made by the vessels mentioned have been
punched onto cards (Fig. 3) as described by Lyman (1953). H.O. Pub.
No. 242 lists the cruises which have been so punched, and H. QO. Pub.
No. 238 is a comprehensive bibliography of the physical oceanography
of the Western Pacific.
REFERENCES
ANDERSON, ERNEST R., Distribution of sound velocity in a section of the east-
ern North Pacific, Trans. Amer. Geophys. Union, v. 31, pp. 221-228, 1950.
BARNES, C. A., D. F. BUMPUS, and JOHN LYMAN, Ocean circulation in Mar-
shall Islands area, Trans. Amer. Geophys. Union, v. 29, pp. 871-876, 1948.
BARNES, C. A., and T. G. THOMPSON, Physical and chemical investigations in
Bering Sea and portions of the North Pacific Ocean, Univ. Wash. Publ.
Ocean, v. 3, pp. 35-79 and appendix, pp. 1-164, 1938.
BRYAN, G. S., Oceanographic activities of the Hydrographic Office and the
United States Navy during 1939, Trans. Amer. Geophys. Union, v. 21,
pp. 333-339, 1940.
Dietz, R. S., Some oceanographic observations on Operation Highjump,
USNEL Rept. No. 55, 97 pp., San Diego, 1948.
GHERARDI, W. R., The oceanographic activities of the Hydrographic Office
and the United States Navy during April 1933 to April 1934, Trans.
Amer. Geophys. Union, v. 15, pp. 188-200, 1934.
The work of the Hydrographic Office of the United States Navy
during April 1934 to April 1935 in the field of oceanography, Trans.
Amer. Geophys. Union, v. 16, pp. 200-214, 1935.
GOODMAN, Jor, and T. G. THOMPSON, Characteristics of the waters in sections
from Dutch Harbor, Alaska, to the Strait of Juan de Fuca and from
the Strait of Juan de Fuca to Hawaii, Univ. Wash. Publ. Ocean., v. 3,
pp. 81-103, and appendix, pp. 1-47, 1940.
HOLTSMARK, B. E., The Sofar project: Hawaiian oceanographic survey U.S.S.
FIEBERLING, Feb.-July 1947, next Rept. No. 139, 58 pp., San Diego, 1949.
612 KIGHTH PACIFIC SCIENCE CONGRESS
Kays, H. E., The oceanographic work of the Hydrographic Office and the
United States Navy from April 1936 to April 1937, Trans. Amer. Geophys.
Union, v. 18, pp. 194-201, 1937.
LAFonpD, E. C., Oceanographic research at the U. 8. Navy Electronics Labo-
ratory, Trans. Amer. Geophys. Union, v. 30, pp. 894-896, 1949.
LAFOonpD, E. C., R. S. DiETzZ and D. W. PRITCHARD, Oceanographic measure-
ments from U.S.S. Nereus on Arctic cruise 1947, usNnEL Rept. No. 91,
San Diego, 1948.
LAFonp, E. C. and D, W. PRITCHARD, Physical oceanographic investigations
in the eastern Bering and Chukchi Seas during the summer of 1947, Jour.
Mar. Research, v. 11, pp. 69-86, 1952.
Leany, L. R., The oceanographic activities of the Hydrographic Office and
the United States Navy during April 1935 to April 1986, Trans. Amer.
Geophys. Union, v. 17, pp. 194-205, 1936.
Lesser, R. M. and G. L. BUFFINGTON, Oceanographic cruise to the Bering
and Chukchi Seas: summer 1949, Part 2: currents, nzz Rept. No. 211,
San Diego, 1950.
LYMAN, JOHN, Oceanographic activities of the Hydrographic Office, 1946-
1952, Trans. Amer. Geophys. Union, v. 34, pp. 122-124, 1953.
SVERDRUP, H. U. and Staff, Oceanographic observations on the U.S.S. BUSH-
NELL in 1939, Records Obs. Scripps Inst. Ocean., v. 1, pp. 66, 123-128,
1943.
U.S. Hydrographic Office, Pub. No. 212, Dynamic oceanographic data for the
central eastern Pacific Ocean, pp. 1-38, Washington, D.C., 1934.
U.S. Hydrographic Office, Pub. No. 238, References on the physical ocean-
ography of the Western Pacific Ocean, 174 pp., Washington, D.C., 1953.
U.S. Hydrographic Office, Pub. No. 242, Vessel and source listing of oceano-
graphic data, Washington, D.C., (mimeographed) 1952.
U.S. Hydrographic Office, Pub. No. 568, Atlas of surface currents, South-
western Pacific Ocean, Washington, D.C., 1954.
U.S. Hydrographic Office, Pub. No. 569, Atlas of surface currents, North-
western Pacific Ocean, Washington, D.C., 1950.
U.S. Hydrographic Office, Pub. No. 570, Atlas of surface currents, North-
eastern Pacific Ocean, Washington, D.C., 1947.
3
618
IFIC CIRCULATION
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FIGURE 2
617
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QYVO WVLI9
ON THE VARIATION OF THE KUROSHIO NEAR
THE JAPAN ISLANDS
By D. SHoji and K. Supa
Hydrographie Office, Tokyo, Japan
INTRODUCTION
There have been many investigations concerning the nature of the
Kuroshio, but the study on its variation is yet very rare, and the hourly
variations of its pass and strength may be said to be almost unknown.
In recent years, as the results of oceanographic observations gradually
piled up, it was made clear that the ocean currents which have been
thought rather stationary, made a comparatively violent variation. But
the observations are very poor compared with other scientific fields, for
example, with meteorology. The cause or the mechanism of variation
of ocean current can not be cleared at the present time. We intended,
therefore, in the following only to describe some example of the ob-
served variation of the Kuroshio.
1) A Cotp WATER Mass OFF THE SOUTH Coast or Honsuu
It was first reported by fishermen in 1934 that a large cold water
mass of a diameter of about 100 sea miles appeared off the south
coast of Honshu and that the Kuroshio flowed around this cold water
mass. According to this report the Hydrographic Office, the Meteor-
ological Observatory and the Fisheries Research Institute of Japan
made many oceanographic observations in this area (Figs. 1-5). At first
this cold water mass (the water temp. at 200 meters was about 10°C in
it and the opposite side of Kuroshio about 18°C) was off the Kii Penin-
sula, and then moved eastward a little and its existence was confirmed
until 1944. Owing to the War the observation was interrupted, and
when reopened in 1946 the cold water mass was much contradicted, and
then disappeared. Hereafter, the cold water mass appeared in winter
of 1946-47, 1950-51 and 1952-53 in this area, but it did not so devel-
op, and the appearance of this cold water mass seems to be a seasonal
phenomenon in recent years. It is clear from the T-S diagram and other
evidences that this cold water mass is a consequence of the upwelling
of the cold intermediate water. But why this upwelling happens so
extensively and why the Kuroshio runs around this, departing from the
Japanese coast, has not been satisfactorily shown. It is true that the
619
620 EIGHTH PACIFIC SCIENCE CONGRESS
bottom configuration of this area is suitable for an upwelling. Dr.
Uda and Dr. Koenuma explained this phenomenon as follows: When
the North Pacific High Salinity Water (Kuroshio Water) weakened
and the strength of the Subarctic intermediate water (Oyashio Water)
increased, this cold water mass appeared. He pointed out that prior
to the appearance of the cold water mass in 1934, cold water off the
coast of Sanriku prevailed so intensively that the northeastern part
of Japan had suffered a very cold summer in 1934-35. It may be ex-
plained that the weakening on the Kuroshio in recent years has caused
the appearance of a cold water mass in winter.
Before the appearance of the cold water mass in 1934, the famous
Muroto typhoon had passed the central part of Japan, and in recent
years the cold water mass appeared after a strong typhoon passed near
this area. The effect of typhoon may be one of the causes of the up-
welling of cold water mass.
Summarizing the above observations, the strengthening and weaken-
ing of the Kuroshio and Oyashio is the major cause of the appearance
of the cold water mass and the bottom configuration and typhoons have
much effect on it.
2) A VIOLENT VARIATION OF OCEANOGRAPHIC CONDITION
OFF THE Boso PENINSULA
It is well known by fishermen that ocean currents change their
course and other oceanographic conditions vary in a very short time.
But the oceanographic observation is seldom carried out in so short an
interval that there are few examples for these variations in the record
of observations.
In this paragraph we intend to describe an example in which sev-
eral observations were carried out in a short interval in the same area,
and a large variation of oceanographic condition was observed. But in
this example, too, the shortest interval of observation was 10 days, and
from the variation of observed water temperature, etc., this is not suf-
ficient to make clear the detailed variation which was taking place in
the ocean.
Figure 6 shows the sectional distribution of water temperature ob-
served by the Hydrographic Office from March to May, i944, off the
Boso Peninsula. ‘These five observations were carried out on an almost
similar line (Fig. 7). As in this area the Kuroshio deflects eastwards
departing from the Japan Islands and the Oyashio reaches to the north
of the Kuroshio, the oceanographic condition in this area is very varia-
ble.
Between 3 and 25 March, the water temperature lowered to about
3-4°C in the whole region, and on 11 April there appeared a minimum
VARIATION OF THE KUROSHIO NEAR THE JAPAN ISLANDS 621
of very low temperature (and very low salinity) of 3-4°C at 200-meter
layer near the coast. (This temperature minimum is a very rare phe-
nomenon as this appeared so far south.) These results indicate that the
Oyashio came down farther south than usual. On 22 April, 11 days aft-
er the former observation, the temperature minimum disappeared com-
pletely and the isotherms inclined so sharp that this indicated that there
was a strong northeasterly current, that is the Kuroshio was flowing in
this area. From the observation of 9 May, the temperature rose gen-
erally and warm water occupied this area.
The variation of the sea water has close connection with the me-
teorological conditions. So we examined the wind observed at the Chosi
Weather Station. From 13 March to 11 April northern winds prevailed.
On 18 and 28 March and 8 April the wind velocity exceeded 20 m/s
(wind direction N or NNE) and on 18 March and 8 April winds of
more than 10 m/s continued more than 24 hours. After 11 April it
was generally calm and the wind direction was variable. From these
data it may be concluded that the southward flow of cold water from
March to April was caused by the strong north wind of the same period.
3) ‘THE TRANSLATION OF THE KUROSHIO AND ITS PERIODIC CHARACTER
AS OBSERVED BY THE MEAN SEA LEVEL
Due to La Fond the variation of water level observed at tidal
stations (the effect of tide eliminated by taking suitable mean values)
is almost the same as the variation of dynamic height of the neigh-
bouring sea surface.
The difference in the dynamic height on both sides of an ocean
current like the Kuroshio reaches as much as about 100 cm. There-
fore if water level is observed at an island situated in the stream of
the Kuroshio, we can know the translation of the Kuroshio continuously.
For this purpose we put a tidal station at Hachijo-sima, and observed
the variation of water level, and at the same time the record of three
tidal stations on the coast of Honshu were also examined. As the va-
riation of the current was very sharp in some cases, we used daily mean
sea level (25-hour mean); and to eliminate the barometric effect, cor-
rection was performed assuming 1 mmb. of air pressure corresponds to
1 em. of water level. Air pressure was taken from the record of the
nearest weather stations.
At first it is necessary to examine whether the mean sea level varies
parallel with the dynamic depth or not. Figure 8 shows the correlation
between the dynamic depth obtained from oceanographic observations
and the sea level. As both values have error of a few centimeters, we
can conclude that proportionality exists fairly well between these values.
622 EIGHTH PACIFIC SCIENCE CONGRESS
The observation of mean sea level at Hachijo-sima has been con-
tinued since May 1951. Figure 9 shows the results from September 1951
to September 1952, with the values of Kushimoto, Ito and Mera Tidal
Stations (Central Meteorological Observatory). ‘The position of the
tidal stations is shown in Figure 10.
(i) The range of variation of mean sea level at Hachijo-sima was
very large compared with other tidal station. While the differences
between maximum and minimum were about 50 cm. at other stations,
the difference at Hachijo-sima reached to 140 cm. This was caused
by the translation of the Kuroshio. To demonstrate this we shall com-
pare the variation of sea level with the oceanographic observations car-
ried out in the same period. The water level at Hachijo-sima was be-
tween 250 cm. and 260 cm. until September 1951. Then it lowered
greatly from the middle of October and from November 1951 to April
1952 (December 1951-February 1952 observation lacked) it remained
between 170 and 220 cm. At the beginning of May, it rose suddenly
about 50 cm. and then continued to rise slowly until September 1952.
According to the oceanographic observations, in May-August 1951, the
Kuroshio was obviously to the north of Hachijo-sima, in September—De-
cember, as there was no observation, the condition was not clear, but
from the Ten-day Marine Report of the Central Meteorological Obser-
vatory, there appeared a cold water mass in this area. In February 1952
a cold water mass was situated in Enshu-nada and the Kuroshio run
around this and Hachijo-sima was situated at the north boundary of
the Kuroshio (Fig. 5). In April the Kuroshio was flowing near Miyake-
sima. ‘These facts were well coincided with the variation of sea level,
and we can conclude that by the observation of sea level, it is possible
to pursue the translation of the Kuroshio.
The slope of sea surface at the strong current of the Kuroshio can
be assumed to be about 10-15 cm/10 miles. Therefore, that the sharp
rise of the sea level at the beginning of May was a rate of about 10
cm/day, indicated that the velocity of translation of the Kuroshio was
5-10 miles/day, namely 0.2-0.4 knots.
This cold water mass was much smaller in scale and continued in
shorter time than the one mentioned in the preceding paragraph. Ii
is interesting to note that before the appearance of this cold water mass
a strong typhoon, Ruth, had swept over our country on 15 October,
(ii) It was made clear that the variation of mean sea level at Ha
chijo-sima had close connection with the translation of the Kuroshio.
The most interesting point in the variation is that there appear some
remarkable periodic changes and this may indicate that there are cor-
responding meanderings of the Kuroshio.
VARIATION OF THE KUROSHIO NEAR THE JAPAN ISLANDS 623
The most distinguished one was seen from March to April, 1952.
The period was 20-30 days and the wave height was 30-50 cm. As the
number of waves is only a few, it can not be decided whether this is a
durable phenomenon or not. But it is clear that this is due to the trans-
lation of the Kuroshio from the large range of variations.
From May to September 1952, there appeared a periodic change of
sea level of much smaller amplitude than the former one. Figure 12
shows the 5-day moving average of mean sea level. “The mean of wave
height was 5 cm. over a period of 14 days. As the amplitude of this
wave is rather small, it is not possible to conclude that this is due to the
oscillation of the Kuroshio. But it may not be the wave of astronomical
origin, for if it is one of the astronomical tide, it must appear in every
time and place. Whether this wave is progressive or not, and also its
wave length and velocity, can not be decided on account of lack of ma-
terials.
(ui) In September 1951 and 1952 the Kuroshio was to the north of
Hachijo-sima in both cases. But the monthly mean level was higher
about 34 cm. in 1952 than in 1951, and the difference between Hachijo-
sima and Ito was 27 cm. in two cases. ‘The difference of sea levels on
both sides of the Kuroshio is proportional to the mean velocity of the
Kuroshio. ‘Therefore, this means that the Kuroshio was stronger in
September 1952 than in 1951. In fact, from the observation, the Kuro-
shio was very strong in the summer of 1952 as compared with usual
years. Hachijo-sima is not the most suitable position to know the
strength of the Kuroshio, for it often comes out of the stream.
It may be very important for oceanography to know the annual
and secular variation of the Kuroshio by observation of sea level at
some adequate places.
(CONCLUSION
We have described some example of variation of the Kuroshio, but
the variation of the Kuroshio can not be cleared up without the co-
operation of the scientists of all nations around the Pacific, for the
Kuroshio is only a fraction of the great circulation of the Pacific Ocean.
REFERENCES
M. UpaA. On the Correlated Fluctuation of the Kuroshio Current and the
Cold Water Mass.
C. O’D. ISELIN. Preliminary Report on Long Period Variations in the Trans-
port of the Gulf Stream System. Papers in Phys. Oceanogr. and Meteor.
Vol. VIII, No. 1.
E. C. LA Fonb. Variations of Sea Level on the Pacific Coast of the United
States. Jour. Marine Research. Vol, 2. 1939,
EIGHTH PACIFIC SCIENCE CONGRESS
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(9)
oo fee SS eee
logy 2 eiloe es k k
Coma Cr
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 651
It is not necessary to calculate o at every observation, rather the
mean values of temperature and salinity may be evaluated similarly to
Equation 5, and the mean value of ¢ computed from them in the usual
way. Having evaluated g in each zone, these may be treated in the
usual manner to discover the dynamic height.
This procedure reduces the number of calculations and is probably
more accurate than the usual computations based on linear interpola-
tion between observations.
DEDUCTIONS REGARDING MECHANISM AND STRUCTURE
Origin and Behaviour of Water Masses
It has long been recognized that sea water occurs as masses, each
having characteristic values of temperature, salinity or other properties.
Usually these water masses are generated in some locality such as the
Arctic, the Tropics, estuaries, etc. As they move out from the sources
they over-ride the more dense, or under-run the lighter waters that are
encountered enroute.
It is supposed that a water mass must be subject to internal turbu-
Jence if it is moving at an appreciable rate, since the Reynold’s Num-
ber in all natural flows far exceeds the threshold of turbulence. Each
water mass tends to pursue its own course and speed and so is inde-
pendent to some extent. Consequently, there is a region of boundary
turbulence resulting from the shear between water masses.
Turbulence, regardless of its course or location, may be regarded
as the random exchange of fluid elements normal to the plane of mo-
tion. In the vertical direction it is statistically similar to diffusion, and
results in exchange of properties through a zone.
This is indicated by the derivatives of the observed relation (Equa-
tion 1)
= : (6)
where z refers to the total depth from the surface. This implies that
the limit of every zone is virtually at the sea surface.
The slope constant (k), as shown in Equation 2, depends only on
the thickness of a zone, and the difference of the values of the properties
at the upper and lower limits. It describes the physical character of
the zone at the instant of observation, and is not, by itself, indicative
of the mechanism by which the zone is created. It is possible to ima-
gine a situation where there were two water masses with identical turbu-
Jence (energy) characteristics. An upper, boundary, and lower zone
would be formed, each having a different gradient of properties. ‘] he
mechanism of mixing is revealed by the form of the relation, and the
source of the exchange is truly at the surface.
oP k
652 EIGHTH PACIFIC SCIENCE CONGRESS
On further consideration, it is evident that in any case the source
(or sink) of the property may always be referred to the surface, since
the process of mixing is continuous at all depths, even though the rate
may vary.
There is a temptation to associate each zone with a region of a
particular degree of turbulence. For example, the nearly homogeneous
zones might represent the region of internal turbulence in a water mass,
while the boundary zone would represent the extent of the added tur-
bulence induced by the shear between water masses. However, this
would imply that the structure at a single position was an expression
of the energy characteristics of the system. ‘The structure reveals the
mechanism, and is surely a result of the energy characteristics, but the
energy distribution can only be expressed by the difference between
structures. Furthermore, there is no quantity of time in the definition
of the structure (Equation 1) and finally it has been shown that the
slope of the gradient can be readily explained by the dimensions and
distribution of the water masses.
It is concluded that each zone is an independent structure, be-
haves as if it were the only zone present, and as. though its source or
sink were at the surface. This concept is implied in the evaluation of
the constant (c) in Equation 3. It is supposed that there is a surface
layer of unit thickness, and of constant properties (P) and that it is con-
tinually being renewed, so that it acts as an inexhaustible source, or
sink.
In the simple case where the water masses are not affected by ex-
ternal factors such as insolation or precipitation, the structure in each
zone tends towards homogeneity. But at the same time the conditions
at the limits of the zones are being renewed by transfer of water from
elsewhere. Each zone is a source and sink for its neighbours, so that
one zone cannot become homogeneous while the character of its neigh-
bours remains unchanged. Rather the gradients in the several zones
tend to become congruous, and then the whole structure tends to degen-
erate towards homogeneity. ‘This process is well illustrated by the se-
quence of salinity observations shown in Figure 8. ‘The step structure
is very apparent near the mouth of the Fraser River, but with increasing
distance the steps become less and less apparent as the structure becomes
mature.
The tendency towards homogeneity can only be opposed by the
introduction of new sources of properties. For example, the surface
water may be heated diurnally so that a gradient of temperature, as
shown in Figure 9A, is formed. During the night the surface is cooled,
or the zone is mixed to homogeneity by the wind so that a single step
structure is formed as in Figure 9B. ‘The effect of further heating and
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 653
homogenizing is indicated in structures C and D. Eventually a step
structure such as E may result. It is important to realize that each
advection must tend toward congruity as it becomes deeper, and more
mature, because once removed from the source at the surface no further
advection can take place, and the homogenizing tendency proceeds un-
checked. ‘Thus step structure degenerates towards a simple logarithmic
gradient at maturity. Obviously step structure with respect to any
property can occur at any depth or zone where a new source of sink is
provided. Excellent examples of such deep phenomena occur in the
margins, and confluences of the great ocean currents.
The Meaning of Structure
Studies now in progress indicate that each structure is a historical
record of the influences and processes which the water masses have
experienced in the sea. ‘These are too extensive for general discussion
here, but one simple example may be cited for illustration.
The origin of the minimum temperature zone in the northeast Paci-
fic Ocean has been made apparent by the seasonal sequence of structures
shown in Figure 10. In March, towards the end of winter the upper
zone waters are isothermal and at a minimum temperature, somewhat
colder than the top of the deep zone. As the season advances the sur-
face waters are warmed by vernal heating. This process may be re-
garded as the accumulation of heat from successive afternoon effects
and wind mixing, as illustrated in the sequence of structures in Figure 9.
The warm upper zone continues to increase through the summer to
mid-September. However, in the autumn the surface cools and the
violent winter storms mix the waters. In this process the upper zone
cools but continues to become deeper. Eventually its boundary inter-
cepts the remnants of the previous winter boundary, and finally the
characteristic late winter structure is formed.
CONCLUSION
It is evident from these remarks that the concepts of zones and
logarithmic structure are at least plausible, and the consequent tech-
nique of the log-plot affords a new and powerful oceanographic tool.
The present examinations have been limited to the coastal and oceanic
waters of the northeast Pacific Ocean, but it appears that the principles
involved should be general. However, such a conclusion must await
study of data from other places, and examination of the ideas by other
oceanographers. It is hoped that such studies will enrich the present
experience.
654
FIG.
Fic.
Fic. 3
FIG.
FIG.
FIG.
FIG.
Fic.
Fic.
Fie.
EIGHTH PACIFIC SCIENCE CONGRESS
ILLUSTRATIONS
1.—Idealized examples of simple salinity and temperature structures
showing the characteristics of the natural-plots and log-plots.
2.—Types of simple temperature and salinity structure. There is an
upper and lower zone separated by a boundary zone. LHither the
upper or lower zone may be absent or they may be congruous.
—Types of complex structure where the successive gradients of pro-
perties in the boundary zone continue to increase or decrease from
segment to segment.
4.—Method of analysis of the logarithmic gradient in the boundary zone.
The conventional. interpretation is indicated by the solid lines. Other
possible interpretations are indicated by the dashed lines.
5.—Bathythermograph, Latitude 50° 24’N, Longitude 131° 34’W, 0304,
7 August, 1951. This illustrates step structure whose mean gradient
approximates a logarithmic gradient within small limits of error.
The circled points represent the standard depths that would have
been observed in a serial observation.
6.—Log-plot from a series of half-hourly BT observations in Juan de
Fuca Strait, Latitude 48° 13.8’N, Longitude 124° 09’W, 4 July, 1952.
These demonstrate that the hourly variation in the fine structure,
and in the depth and magnitude of the boundary zone, are greater
than the deviation from the best straight line through the points.
7.—Log-plots of the serial observations at Latitude 54°21’ N, Longitude
140°05’ W, on 0730, 10 August, 1950. These show that the structure
with respect to each independent property is unique.
8.—Application of the concept of index salinity in logarithmic structure
to the illustration of oceanographic data.
9.—Idealized temperature structures illustrating the formation and de-
generation of step structure due to diurnal heating and cooling in
the upper zone.
10.—Idealized sequence of structures illustrating the annual temperature
cycle in the upper zone in the northeast Pacific Ocean. (Reference
. DOE)
3.
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 655
4 SALINITY
26 Yo 30 34 26 “eo 30 34
=i =
meters
1000
TEMPERATURE
20 0 °C
meters
500
= 1000 = 1000
NATURAL PLOT LOG - PLOT
FIGURE 1
H1d3a
656
KIGHTH PACIFIC SCIENCE CONGRESS
SALINITY (S%o)
TEMPERATURE (°C)
FIGURE 2
Hid3jQ
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 657
SALINITY (S%c)
30
30 “oo 30
BOUNDARY
TEMPERATURE (°C)
5 10 is)
10
FIGURE 38
658 EIGHTH PACIFIC SCIENCE CONGRESS
TEMPERATURE (°C)
! 10
Sf ale) oneall | 200
Points | Points | Points
Sey ae r i0o
1006
FIGURE 4
TEMPERATURE (°F)
40 °F 50 60 40 °F 50 60
feet feet
F100
= 200
{00
300
400
NATURAL PLOT LOG - PLOT
FIGURE 5
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 659
TEMPERATURE (°F )
45 °F 50
FIGURE 6
TEMPERATURE SALINITY DENSITY DISSOLVED
OXYGEN
XG S%oo Ostp mg /|
5 10 32 33 34 24 26 28 30 8 9 10
100
1000
FIGURE 7
660 EIGHTH PACIFIC SCIENCE CONGRESS
oeere'123° 30' W Ng
fF
amt Yas 09
Depth (feet) of index salinity (29.4%) in Georgio Strait
20
May 15—22,1950
Index S alinity
29.4 Ya
100
Salinity Zone Structure in Georgia Strait
FIGURE 8
SOME CHARACTERISTICS OF SEA WATER STRUCTURE 661
TEMPERATURE (°C)
FIGURE 9
TEMPERATURE (°C)
Summer
Boundary
Cs?
Winter Boundary a
MARCH JULY SEPT. NOV, DEC. MARCH
ey TING ——| Ea COOLING ——>|
FIGURE 10
100
1000
meters
100
1000
ON THE CIRCULATION IN THE NORTH PACIFIC IN
RELATION TO PELAGIC FISHERIES
By MicwitTaka UpA
Tokyo University of Fisheries
Kurihama, Yokosuka City, Japan
On the charts plotted by the author, the semi-permanent boundaries
of the water masses (fronts) in the Northwest Pacific adjacent to
Japan, i.e. the Coastal Fronts, Oyashio Front (Polar Front or Subarctic
Convergence), Kuroshio Front, Warm and Cold Fronts in the Japan
Sea, Subtropical Convergence, Equatorial Counter Front, Continental!
Front are shown in relation to pelagic fisheries grounds of tuna, skip-
jack, Pacific saury and whales (Fig. 1). Briefly we can summarize the
following three types of pelagic fishing grounds on the above hydro-
logical point of view:
(1) Those produced by the planktonic livings and fishes in the
compressed zone of the optimum water temperature due to mere con-
vergence (e.g. the skipjack fishing grounds in the northern boundary
zone of Kuroshio and the Pacific saury fishing grounds near the Oya-
shio Front),
(2) Those produced by marine organisms due to the upwelling
of the water of rich nutrients in the deeper layer obeying Nathansohn’s
theory (e.g. the fishing grounds of sardine, squid, yellow-tail, bluefin
tuna, mackerel, etc., or some varieties of this type), indicating dense
“ concentrations near the coastal front and the fishing grounds on the
eddies around the islands or capes (mackerel, flying fish, etc.) and
around banks (skipjack, tuna and mackerel, etc.).
(3) The combined fishing grounds of (1) and (2) types (eg.
the marginal convergence of the upwelling area at the front of the
cold water such as the fishing grounds of the albacore, whales, Pacific
saury, etc.).
Further we will inspect the oceanographic structure in the North
Pacitic by means of the nucleus method. ‘The depth of the inter-
mediate water S min. and the value of that depth during the period
1931-41 were plotted in Figures 2, 3 and 4.
The intermediate water in the Northwest Pacific may be con-
sidered as the carrier of the rich nutrients which are produced in the seas
of high latitudes and fertilizer resulting in the high production in the
seas of lower latitudes. The prevalence of the cold water circulation,
663
664 EIGHTH PACIFIC SCIENCE CONGRESS
i.e. the prevalence of the intermediate water, was associated with the
anomalous Kuroshio conditions in recent years (1935-47).
The northern intermediate water appears to extend conspicuously
to south along the Japan Trench and invades in the sea basin south
to Japan. Going south further, it descends to its deepest layer beneath
the depth of 800 m. in the sea-region at about 34-24°N. with the sal-
inity of 34.0-34.2 °/,, and rises again gradually up to the depth of 200 m.
at about 5°N., showing the increase of salinity to 34.5 °/oo.
The northern and southern intermediate waters collide with exch
other in the zonal region of the latitudes of 12°-2°N., lying at about
the depth of 200 m. for the former (the Northern Intermediate Water)
and at about the depth of 800 m. (600-1000 m. depth) for the latter
(the Southern Intermediate Water).
Accordingly in that region the vertical distribution of salinity shows
the double minimum which is produced by the stratification of the
southern intermediate water beneath the northern intermediate water.
The distribution of the depth and the value of the maximum
salinity Sax: In the subsurface tropical water mass (Fig. 5) in-
dicates obviously in the deepest layer (100-200 m. depth). Sax, lies
in the regions of the North Equatorial Current (latitudes 20°-10°N.)
and in the Kuroshio area. It lies in the shallowest layer (0-100 m.
depth) in the western part of the North Pacific Saline Water (Salinity
more than 35 °/,.), having its axis along the line of Subtropical Converg-
ence (water temperature in the upper layer above the 100 m. depth in-
creases suddenly in the south over this Convergence).
In the Equatorial Counter Current area the depth of S,,,,. again
rises to its shallowest (depth almost less than 100 m.) above the opti-
mum angling depth of tuna with the salinity of about 34.8 °/,, or less,
which corresponds to the belt of the cold water (water temperature
less than those in the surrounding north and south).
Beyond it to the south (latitudes 3°N.-3°S.), again the S,,,,. layer
sinks beneath 100-200 m. depth with the high salinity of 35.0-35.7 °/o9,
which corresponds to the water of the South Equatorial Current.
The distribution of surface salinity in winter and summer during
the period 1931-35 (Fig. 6) shows the expansion of the North Pacific
Central Saline Water mass in winter, lying in the zone of lat. 20°-30°N.
around the axis of 22°-26°N., 165°-180°E., and the shrinkage in sum-
mer season in the period of 1931-35.
The water mass of low surface salinity (34.0-34.3 °/,.) lying in the
zone of the Equatorial Counter Current (lat. 5°-12°N.) which cor-
responds to the Equatorial Calm or Equatorial Rainy zone, and also
CIRCULATION IN RELATION TO PELAGIC FISHERIES 665
to the belt of the cold water at the depth 100 m. appearing more re-
markable in winter than in summer.
In the region south from the lat. 4°N. to 3°S. we meet again the
saline water mass of the Central South Pacific (salinity 34.5-35.2 °/,,).
The northern and southern boundary lines of the Equatorial
Counter Current (Equatorial Counter Front) lie at about 12°N. and
4°N., corresponding to the theoretical results obtained by Dr. K. Yo-
shida and others (1953).
(ap)
(orp)
fos)
EIGHTH PACIFIC SCIENCE CONGRESS
ILLUSTRATIONS
Fic. 1.—Principal Watermasses and the Fronts in the NW Pacific. Explana-
tion of Notations: LC—Liman Current, NKC—North Korean Cold
Current, JCC—Central Cold Current in the Japan Sea, EKC—East
Korean Warm Current, TC—Tsushima Current, CCC—Continent
Coastal Current, ConF—Continental Front, CF-—Cold Front in the
Japan Sea, WF—Warm Front in the Japan Sea, KC—Kuroshio Cur-
rent, OC—-Oyashio Current, ESC—East Saghalin Cold Current, OF—
Oyashio Front, KF—Kuroshio Front, STC—-Subtropical Convergence,
NEC—North Equatorial Current, ECF,, ECF,—Equatorial Counter
Front, SEC—South Equatorial Current, ECC—Equatorial Counter
Current, CoF-—Coastal Front.
Fic. 2.—Smie. (°/99) and its Depth during 1931-1935. (Shaded area
means the zone ot Double Smin.).
Fig. 3.—Smin. (8/95) and its Depth during 1935-1938. (Shaded area
means the zone of Double Smin,).
Fic. 4.—Smin. (9/5) and its Depth during 1988-1941. (Shaded area
means the zone of Double Smin.).
FiG. 5.—Smax. (9/99) and its Depth during 1931-1938.
FIG. 6.—Som. (°/,,) in Winter (Real line) and in Summer (Dotted line)
1931-19385.
CIRCULATION IN RELATION TO PELAGIC FISHERIES 667
/30° /40° 150° 160°
Fishing Locabsties : | \) ‘\ gC
@ Albacore 5 i)
© Yellowfin tiema is Ja v
@ Btuefin tena
O Skippack
A Pacckc Saury
S Sardcne
We) FRY ing fuse
q Soudd
m Sgue Ge
ye
fm Mackere
Oz
Uiee
FIGURE 1
685
EIGHTH PACIFIC SCIENCE CONGRESS
FIGURE 2
669
CIRCULATION IN RELATION TO PELAGIC FISHERIES
§ GY
EIGHTH PACIFIC SCIENCE CONGRESS
670
y ANNDI Ky
671
CIRCULATION IN RELATION TO PELAGIC FISHERIES
G WMNDIY
9 GUND
oO.
°
Fic. 1—Surface topography during northeast monsoon.
EIGHTH PACIFIC SCIENCE CONGRESS
130°
CRUISES 23,24,25 AND 26
DYNAMIC HEIGHT ANOMALIES |(DYN. M)
AT SURFACE
SULU SEA- 0 OVER 800 DCBS
SOUTH CHINA S. AND PACIFIC OC.
O OVER 2000 DCBS.
CONTOUR INTERVAL - 0.02M
cAuIse 26 90
ocY. 12-23,1968
cruise ep ®
WULY 1@- aue ui, ay
oe
e
HALMAHERA eo
Fic. 2.—Surface topography during southwest monsoon.
RECENT OCEANOGRAPHIC EXPLORATION IN THE NORTH
AND EQUATORIAL PACIFIC OCEAN
By WARREN S. WOOSTER
Scripps Institution of Oceanography
La Jolla, California, U.S.A.
The exploration of the Pacific Ocean may be divided into three
major phases. The first phase, that of geographical discovery, was ini-
tiated by Magellan and reached its climax in the voyages of James Cook.
Karly in the nineteenth century the general outline of the shores and
the locations of most island groups of the Pacific had been fairly well
established. Yet the early explorers were not oceanographers, and in
their travels they discovered little about the sea.
The second phase of Pacific exploration and the science of deep-sea
oceanography were both opened by the cruise of HMS CHALLENGER
in 1873 to 1876. For the first time a major expedition was devoted to
a study of the ocean itself, the physics and chemistry of its waters, the
character of its bottom and the nature of its denizens. Expeditions in
the great tradition of the CHALLENGER have continued up to the pre-
sent day, notable among them being the cruises of the DANA and the
CARNEGIE in 1929 and the recent voyages of the ALBATROSS and the
GALATHEA, Such studies lead to a general description of the major
characteristics of the Pacific Ocean from the physical, chemical, biolo-
gical and geological points of view.
The third phase of exploration can be described as the detailed
~ study of the spatial and temporal changes in conservative and non-con-
servative concentrations. The ocean is considered as a dynamic system,
and the goal of this phase is the description and understanding of the
processes bringing about changes in this system. Much work of this
sort has been done already by scientists on both sides of the Pacific,
using the classical tools of oceanography. ‘The successful prosecution
of this phase, however, requires eventually the development and appli-
cation of new tools (such as the bathythermograph, geomagnetic electro-
kinetograph or high-speed plankton samplers) which can be used from
a moving ship.
Although the five post-war expeditions of the Scripps Institution
of Oceanography have made use of such new tools, their results belong
properly to the second phase of exploration. The two expeditions in
which the author did not participate differed in purpose from the others
679
580 EIGHTH PACIFIC SCIENCE CONGRESS
and will be mentioned only briefly here. The MID-PACIFIC Expedition
of 1950 in the eastern North Pacific, and the CAPRICORN Expedition
of 1952-1953 in the Central Pacific were principally geological and
geophysical in intent, studying the shape of the sea floor with the echo-
sounder, the character and depth of bottom sediments with bottom
samplers and by seismic refraction methods, and the transport of heat
through the sea floor with the bottom temperature probe.
The NORTHERN HOLIDAY Expedition of 1951 in the eastern
North Pacific, the SHELLBACK Expedition of 1952 in the eastern Equa-
torial Pacific, and the TRANS-PACIFIC Expedition of 1953 in the deep
Bering Sea and the western and central North Pacific, were similar in
basic purpose. In each case the course was laid out to cross the major
current systems and to sample the principal water masses of the area.
In each case the major work of the expedition was a series of hydrogra-
phic stations at 60- to 90- mile intervals where temperature and salinity
were measured down to considerable depths, chemical analyses of water
samples made, and quantitative plankton tows carried out. Between
stations observations were made with the bathythermograph, geomagnetic
electro-kinetograph, echo-sounder and midwater trawl. Geological and
meteorological observations were also made on each expedition.
An effort was made to cross the major circulation features at ap-
proximate right angles to facilitate velocity and transport computa-
tions. By means of water mass and isentropic analysis it will be possi-
ble to map out the distribution of water types and to study their origin
and subsequent transformation. In particular, the distribution of pro-
perties in deep water may cast some light on the little known inter-
mediate and deep circulation of the Pacific. The distributions of dis-
solved oxygen, phosphate and silicate and of planktonic species are
closely related to the distributions of conservative concentrations, and
the results of these expeditions will make possible a careful study ot
this relationship.
In summary, the results of these five expeditions should contribute
substantially to our knowledge of the major circulation and the distri-
butions of properties and organisms in the Pacific Ocean. An under-
standing of time and space variations in this general picture must await
the extension of phase three methods to deep-sea oceanography.
EXPLORATION OF THE NORTH AND EQUATORIAL PACIFIC OCEAN 681
PACIFIC OCEAN
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SCRIPPS INSTITUTION OF OCEANOGRAPHY
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EXPLORATION OF THE NORTH AND EQUATORIAL PACIFIC OCEAN 683
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BASIN WATERS OF SOUTHERN CALIFORNIA
By K. O. EMERY
Allan Hancock Foundation
University of Southern California
Los Angeles, California, U.S.A.
ABSTRACT
Off the coast of southern California are 14 basins that are separated
by submerged ridges. ‘The sills of the basins are 475 to 1900 meters
deep and from 150 to 880 meters above the basin floors. In general,
the basins that are located farthest south have the deepest sills. Water
below sill depth in the basins is isothermal at the same temperature
that was found in the earliest measurements in 1931]. It is also isohaline
except for effects of diagenesis near the bottom. A close relationship
between temperature and sill depth exists,—such that the northern basins
with their shallow sills contain the warmest water. It is evident that
the water in the basins comes from adjoining basins or from the open
sea at a depth which is within 200 meters above to 40 meters below
sill depth. This relationship makes possible the tracing of basin waters,
which were found to flow northwesterly, in contrast to the general
southeasterly moving surface currents.
685
AN OCEANOGRAPHIC MODEL OF PUGET SOUND *
By Ciirrorp A, BARNES, JOHN H. Lincotn and Maurice Rattray, Jr.
Department of Oceanography, University of Washington
Seattle, Washington, U.S.A.
INTRODUCTION
Oceanographic observations must be made in great numbers and
extend over long periods, in many cases years, in order to obtain a re-
latively complete understanding of the conditions existing in even a
small estuary or bay. Resolution of the mass of data to provide the
desired information is further complicated by the fact that none can
be obtained under controlled conditions. Data obtained at different
times are not directly comparable since the natural conditions neither
remain constant nor precisely repeat. Thus a synoptic picture of the
oceanography of an area may be considered only in general terms at
best, and as the size of the area is increased the generalities must of
necessity become broader.
In treating an area as large and complex as Puget Sound, the prob-
lems of obtaining a complete understanding of the over-all oceanogra-
phy, under either normal or extreme conditions, from field observations
alone are almost insurmountable. In recent years, hydraulic models of
tidal estuaries have been used in increasing numbers as a guide in in-
terpreting the conditions within the prototype. It is recognized that
it is impossible to construct a reduced scale model rigorous of the pro-
totype and that distortion and scale effects may easily lead to misin-
terpretation. Nevertheless, these small-scale models are useful in clari-
fying the nature of existing conditions and in planning more efficient
field programs. Observations may be made under controlled conditions
and, of utmost importance, a particular set of conditions may be set
up in the model and repeated at will until all pertinent information
is collected.
DESCRIPTION OF THE AREA
Puget Sound (Fig. 1) branches to the south from the eastern ter-
minus of the Strait of Juan de Fuca, between the Olympic and Cascade
mountains of Washington. Its various arms, averaging less than 3 miles
wide, have a total area of 767 square nautical miles at mean high water.
* Contribution numler 195 from the Department of Oceanography of the University of
Washington. Technical Report No. 19, University of Washington and Office of Naval Re-
search, Contract NSonr-520/III, Project 083-012.
686
AN OCEANOGRAPHIC MODEL OF PUGET SOUND 687
The entire system lies within an area of about 40 by 90 nautical miles.
It may be subdivided into four general sections which are partly isolated
by vertical or lateral constrictions. "The main basin extends from a
40-fathom threshold sill at the confluence of Admiralty Inlet with the
Strait of Juan de Fuca, south to a 26-fathom sill at the Tacoma Nar-
rows. ‘The section south of the Narrows consists of a 100-fathom pri-
mary basin with many branching channels and inlets. Hood Canal,
averaging about 2 miles wide and having a depth of 100 fathoms, ex-
tends about 50 miles southwest from Admiralty Inlet and is partly
separated from it by a 30-fathom sill. The fourth section extends with
diminishing depth from Possession Sound, about 25 miles from the
entrance to Admiralty Inlet, north through Skagit Bay to Decention
Pass. This pass is a very restricted channel about 150 yards wide and
16 fathoms in depth connecting with the Strait of Tuan de Fuca. Pu-
get Sound is relatively deep in comparison with other inshore waters
of the United States with a maximum depth of 155 fathoms and with
50 per cent of its total volume lying below 25 fathoms.
The tides of Puget Sound are of the mixed type characterized by
marked differences in the successive heights of low waters. Consider-
able changes in the tide with respect to character, range, and time
occur within the area. Periodically, the tide near the mouth at Port
Townsend loses its mixed characteristics and for several days each month
becomes virtually diurnal. This effect does not extend into the sys-
tem for any great distance and the tides are semidiurnal over the rest
of the system at all times. The tidal range generally becomes progres-
sively greater landward from the entrance. Port Townsend has a diur-
nal range of 8 feet while the inlets at the southern extremities have
15 feet. The rate of progression of the tidal wave into the Sound is
altered by the topographic characteristics, particularly at the Tacoma
Narrows, a narrow constriction between two of the larger basins, and
changes with the character of the mixed tides.
The tidal currents also are subject to wide local variations and
are dependent upon the tide range. The maximum velocities occur in
constricted channels and may reach about 7 knots. The tidal prism in
Puget Sound amounts to about 5 per cent of the volume below mean
lower low water.
Numerous rivers and small streams feed into Puget Sound from a
drainage basin of about 11,300 square miles within which precipitation
varies locally from 20 to over 100 inches per year. The eleven largest
rivers, having a combined mean yearly runoff of about 40,000 second-
feet, account for about 80 per cent of the total fresh water influx, the
Skagit alone contributing about one third. The peaking characteristics
688 EIGHTH PACIFIC SCIENCE CONGRESS
of the rivers are governed by the major water sources. Lowland rivers
peak during the winter from rainfall. Those rivers having mountainous
areas as their principal watershed peak during the late spring from
snow melt. Others may have both peaks. Hydroelectric developments
on some rivers tend to flatten the peaks and maintain a more uniform
runoff. Discharge varies greatly with flood stages being as much as 150
to 200 times the minimum flow.
The population of the area is over 1.5 million, the principal sea-
board cities being Seattle, ‘Tacoma, Bremerton, Port Townsend, Everett,
Olympia, and Shelton. Virtually all sewage from the municipal systems
is discharged untreated into the Sound. While industrialization of the
area is not heavy, some industries, particularly those manufacturing
pulp and paper, are potential pollution hazards because of the large
volume and high oxygen demand of the wastes.
CONSTRUCTION OF THE MODEL
It is common practice to make tidal models as large as is consistent
with space and facilities available and cost. The horizontal scale is or-
dinarily determined by these empirical] factors. The vertical scale
is governed by the practical requirements for suitable time scale and
water depth in critical areas and by the theories of dynamic and kine-
matic similitude. Space available limited the present model to a hori-
zontal scale of 1:40,000. The vertical scale selected was 1:1,152 or
1/16-inch per fathom, giving a distortion of 34.6:1. With these scales,
the model is approximately 7 feet by 15 feet and has a maximum water
depth of 10 inches with 1-14 to 2 inches over the critical sills. As a
consequence of the distortion, some channels are deeper than they are
wide. The time scale from the Froude modeling law is 1:1,178 or 3.05
seconds per hour, permitting a year’s tides to be observed in 7.4 hours.
With this choice of scales, the Reynold’s number in the model will be
in the turbulent region over the critical sills, for most of the tidal
cycle. ‘That the motion is actually turbulent is easily verified by in-
serting dye into the model and watching its rapid diffusion. The ap-
propriate criterion for turbulence in a fluid with stable stratification
is given by the Richardson number g mites = With Froude modeling,
the salinity scale must be unity to ene the same Richardson number
in model and prototype. With a reduced salinity scale, the mixing in
the model could be expected to be increased.
The customary method of constructing model basins consists of
moulding the contours to conform to templates fixed in position within
the model area. This technique was found unsatisfactory for reproduc-
AN OCEANOGRAPHIC MODEL OF PUGET SOUND 689
ing the fine detailing of contours required by the small scale and the
complex system of narrow deep channels. A method was developed for
casting the model basin in concrete from accurately-contoured hand-
carved wood patterns. The contours used, established from the Hydro-
graphic Charts of the area, were the elevations of mean high water,
75 feet, and 150 feet, and successive ten-fathom depth intervals below
mean lower low water. The area was divided into 25 sections for con-
venience in preparing the patterns. The contours of each were trans-
ferred to white pine lumber planed to the thickness of the contour in-
terval. The sections were then cut along the contour line and laminated
in exact position. Excess wood was removed and the patterns brought
to precise shape by careful hand-carving and sanding with constant re-
ference to the charts for soundings between the contour intervals. Small
basins were provided upstream from the river mouth for introduction of
the river discharge. ‘The wood was brought to a very smooth surface,
sealed and varnished (Fig. 2).
The individual patterns were assembled in an inverted position
upon a strongly supported platform 8 by 20 feet, constructed as a base
for the model (Fig. 3). Forms were built around the assembled pat-
terns with sheet metal separators between the pattern sections to form
easily handled blocks. Copper tubing was placed from the outside of
the forms to the river basins to carry the fresh water. ‘The patterns
were oiled to prevent sticking to the concrete. When the steel reinforc-
ing was placed, a coating of smooth cement grouting was applied to the
patterns. The forms were then filled to a uniform depth of 15 inches
with a standard quick-setting concrete. “Twenty-four hours after the
concrete was poured, the forms were removed, and the blocks separated
and inverted. The patterns were sprung out of the concrete by a meth-
od analogous to removing a tightly fitting stopper from a bottle.
The blocks were reassembled to form the model basin. A bitumas-
tic compound was used to seal the joints between blocks. Surveying
methods, combined with a latitude-longitude grid on the platform af-
forded accurate positioning of the patterns and of the completed sections.
The method used insured precise fitting together of the blocks. The
joints between the blocks and the minor defects which occurred during
the casting were smoothed with plaster of Paris. The basin was finished
with several coats of a vinyl resin paint (Fig. 4).
TIDE-GENERATING MACHINE
The requirements for the tide-generating machine were that it
closely reproduce natural tides and that it be adaptable to any model
of regional waters that might be constructed at these Laboratories. it
690 EIGHTH PACIFIC SCIENCE CONGRESS
was desired further that simple repeating tides could be set up and
that a sequence of natural tides could be conveniently interrupted
and repeated.
The tidal harmonic constants computed by the U.S. Coast and
Geodetic Survey for Seattle and Port Townsend indicated that a mini-
mum of six constituents would be required to reproduce prototype tides
within a deviation of +1 foot. These, the diurnal K,, O,, and P,, and
the semidiurnal M,, N,, and S,, were incorporated in the tide-generat-
ing machine using many principles of the Coast Survey’s prediction
machine. Identical gear ratios were used for corresponding constituents.
A 1/8-horsepower motor was used to drive a line shaft through a
900: 1 reduction box and spur gears at precisely one revolution in 12
solar hours, model time. Scotch yokes, driven from the line shaft by
gear trains at speeds corresponding to the period of each constituent,
generate cosine functions. ‘These are fed into a summation wire con-
nected through a suitable pulley and reduction drum arrangement (Fig.
5) to a plunger located in the model headbox. The changing water
displacement caused by the motion of the plunger, shaped to correct
for the tidal prism, produces the rise and fall of the tides. Phase angles
and amplitudes for any epoch or location are readily set for the dif
ferent constituents on the calibrated cranks of the Scotch yokes. A sup-
plementary chain drive is incorporated between the M, and K, const1-
tuents to provide a means of generating repeating tides of either diur-
nal, semidiurnal or mixed character.
RIVER SYSTEM AND SALT WATER ADDITION
Provision is made for the introduction of fresh water through ele-
ven major rivers of the area having a yearly mean discharge ranging
from approximately 400 to 16,000 second-feet. The water flows by
gravity from a constant head tank, through individual flow meters of
the expanding bed type, to small basins located a short distance up-
stream from the river mouths. ‘The rate of flow of the rivers is con-
trolled manually by means of individual needle valves. Loss of salt
resulting from river runoff is balanced by a circulation system in the
headbox. Water is removed from the headbox through a shaped stand-
pipe and pumped into a reservoir having a capacity of about 125 liters.
Salt solution is added to the water in the reservoir to maintain the
desired density. A second pump returns the water from the reservoir
to the headbox where it is introduced along the bottom at a rate exact-
ly balancing that of removal. In this way the net surface outflow from
Puget Sound and the balancing inflow of oceanic water at depth is
simulated.
AN OCEANOGRAPHIC MODEL OF PUGET SOUND 691
INSTRUMENTATION
The design and development of instruments for measuring and re-
cording tides, tidal currents, and the density structure in the model is
complicated by the small scales and distortion. The sensing ele-
ments must be such that they do not significantly alter the properties
being measured or interfere with the operation of the model. Further,
because of the short time scale, it is necessary to obtain measurements
rapidly in order to adequately differentiate conditions during the tidal
cycle.
A portable recording tide gauge and an instrument for recording
the salinity or density structure in the model have been designed and
constructed. The recording tide gauge will resolve the model tides to
within about 3 inches or 0.003 inch actual change in water level. The
gauge is not affected by surface tension or factors other than change
in the water level in the model. In principle it consists of an inter-
connected probe and recording arm operated by a synchronous motor.
The prabe alternately rises and lowers as the recording arm sweeps a
stylus across electrosensitive paper being moved by a standard recording
tape puller. As the probe, tipped by a fine platinum wire, contacts the
surface of the water, an electrical circuit is completed which fires a
thyrotron tube discharging a condenser. The charge from the condenser
passes from the stylus through the paper to a second electrode consist-
ing of a small roller extending across the underside of the paper. The
discharge causes a small spark to burn a fine hole in the paper making
a permanent black dot. ‘The probe operates at a frequency of once per
second.
The instrument for recording the salinity structure is based upon
the conductivity of the water. The variations in the conductivity of a
vertical section are electronically transposed to a plot of conductivity
versus depth on an oscilloscope which may be photographed for a
permanent record. The conductivity cell consists of a capillary 0.025
inch in diameter and 3/4-inch long, having electrodes at each end
forming an integral part of the capillary. A maximum potential of
about 50 volts at 10,000 cycles may be applied across the cell. Alter-
nating current is used to reduce the effects of polarization of the elec-
trodes. Water is drawn through the cell at a rate equivalent to the rate
of displacement of water by the cell and tube to which it is attached,
as it is lowered through the water. It has been found that measure-
ments must be made while lowering the probe since some mixing and
turbulence occur when the probe is raised, leading to fictitious values.
Response is fast because of the rapid flushing of the cell.
692 EIGHTH PACIFIC SCIENCE CONGRESS
Probing rate and depth of sampling may be adjusted as desired and
operation is automatic. Camera operation is manual at present but
may easily be adapted to automatic operation if desired.
CuRRENT METER
Since the velocities and distances in the model are both very small
compared to those in the prototype, it has proven impossible to use
small-scale standard current measuring devices. The present method of
current measurement consists of introducing small vortex rings of dye
into the water at fixed time intervals and then to photograph their re-
lative positions. This method has proved satisfactory and has the addi-
tional advantage of measuring both components of horizontal velocity
simultaneously. The equipment consists of a glass capillary connected
to a dye reservoir through a T section. A rubber bulb, connected to the
other junction, is tapped at one second intervals by a hammer driven
by a synchronous motor to emit a vortex of dye from the capillary tip.
TIDE AND CURRENT STUDIES
A comparison of the tidal action in the model with that of the
prototype was one of the first detailed studies undertaken as a part of
the validation. The phase and amplitude changes between Port Town-
send and key locations within the Sound were determined for each in-
dividual tidal constituent and compared with corresponding values for
the prototype. Within the main basin, the time lag error was of the
order of 6 minutes, or 0.3 second actual time greater than the Coast
Survey values. Amplitude ratios agreed within 10 per cent. Beyond
the constrictions of the Tacoma Narrows and those leading to Bremer-
ton, the deviations were approximately double these values. A mari-
gram of the six constituents for the first half of 1951 at Seattle was
drawn by means of the tide machine using the Coast Survey tidal con-
stants. “The model tides at Seattle for the same period, generated by
the tide machine adjusted to produce the correct tides at Port Townsend,
were recorded. Portions of the recorded tides were compared with cor-
responding portions of the prepared marigram and with the tide table
predictions (Fig. 6). The average deviation of the recorded tidal
heights from the marigram was less than +0.5 foot. Measurement of
the deviation in time lag was not obtained.
Quantitative measurement of the tidal currents and patterns of
circulation have not been completed. Visual observations indicate that
the model is giving good representation of prototype circulation, current
patterns, and velocities, and the eddy patterns appear to follow quite
well.
AN OCEANOGRAPHIC MODEL OF PUGET SOUND 693
DENSITY STRUCTURE
In the past, most tidal model studies have been concerned with
silting in an estuary or harbor rather than the processes involved in and
resulting from a variable density structure. Little work on the dy-
namics of an inhomogeneous system resulting from the interchange of
oceanic water and river discharge in tidal models has been reported in
the literature, and the theoretical requirements for similitude in this
respect are not well resolved. It is thus necessary to determine the ef-
fects and interrelationships of the variable parameters in a model before
representation of the prototype may be achieved. A series of studies
was initiated to investigate the density structure as it is one of the ma-
jor factors influencing the oceanography of Puget Sound. When the
model structure under various conditions is known, it can be correlated
with nature to establish any major differences and demonstrate possi-
ble corrective measures. For the purpose of this work, the salinity
structure in each of the four main sections of Puget Sound was typified
by measurements at Point Jefferson, Camano Head, Green Point, and
Hood Point, (Fig. 7), under controlled conditions of tide, river run-
off, and source salinity. (Repeating tides with an average range and
diurnal inequality were used throughout this series of studies.)
In the first experiment, the equilibrium situation was obtained for
mean river flow with a source salinity of 16°/,., which, for the purpose
of simplifying comparisons, has been related to a prototype salinity of
32°/49. The results (Fig. 8) in general show a fresher surface layer
with sharp gradients to a depth of 10-30 meters, below which there is
a practically homogeneous more saline layer extending to the bottom.
At first, it might appear that the homogeneous bottom layers were due
to a lack of mixing of fresh water down from the surface; but that
this is not the case is shown when the salinity of this bottom water is
compared with that of the source water. At Point Jefferson and Ca-
mano Head, the bottom saiinity is about 1°/,, less than the source,
while for Green Point the difference is about 1.5°/,,, which com-
pares favorably with the differences obtained in nature. It must be
that the mixing in these lower layers is sufficient to destroy any initial
gradient.
The influence of the fresh water runoff on the salinity structure
is best seen from the results of raising the flow of the Skagit River to
the normal flood discharge rate of 50,000 c.f.s. (Fig. 8). After 1,000
consecutive days of flood, the effect of fresh water was noticed only to
a depth of 80 meters at Point Jefferson although the surface layer had
definitely freshened and deepened. At Camano Head, on the other hand,
the deep water had freshened somewhat with no perceptible change in
694 EIGHTH PACIFIC SCIENCE CONGRESS
the surface layers. Since the mechanism of these changes is not im-
mediately clear, it will be a subject for further investigation. Off Green
Point, the whole water column was freshened as would be expected since
strong mixing occurs in that region and its water source is mainly the
surface layers of the main basin. Thus even under these extremely
extended conditions of flood, a noticeable gradient can not be main-
tained beneath the surface layers and another mechanism must be
found to simulate the gradients which occur in nature.
Since in nature the source water of the Strait of Juan de Fuca
does not hold a constant salinity throughout the year, the effects of a
change in source salinity was investigated in the model. In order to
make results clear-cut. a sudden decrease of salinity of 10°/,., was main-
tained for 166 days and then increased back to its original value.
The decrease in source salinity (Fig. 9) was first noticed at Point
Jelterson. A uniform gradient to a depth of 100 meters developed
within 45 days. Subsequent mixing of these waters produced a homo-
geneous salinity to this depth with a sharp interface separating it from
the more saline bottom water by 101 days. Mixing then gradually low-
ered the interface. The changes in salinity below 100 meters were
minor during the first 101 days. As would be expected from the proxi-
mity and lack of sill between Camano Head and Point Jefferson, the
sequence of events was very similar for the two stations. At Green Point,
the salinity decrease was later at the surface, but when it did occur
it was felt almost to the very bottom. After 166 days, the salinity was
homogeneous in the bottom layer. At Hood Point, the fresher water
was only noticed to a depth of 50 meters after 45 days, and only to
about 70 meters after 166 days with very little change in the salinity
of the bottom waters. Correspondingly, in nature the bottom water in
Hood Canal has a tendency to stagnate.
An increase in source salinity produces a series of density gradients
markedly different than above in both shape and rate of change (Fig.
10). Within 24 days, there was a considerable increase in salinity of
the bottom water at Point Jefferson with the appearance of an almost
constant gradient between the depths of 30 and 150 meters. After 38
days, the surface gradient was increased to a depth of 50 meters and
decreased below that depth. This pattern continued until equilibrium
conditions were reached after 89 days. At Camano Head, the salinity
structure went through the same sequence although the mixing ap-
peared to be faster between 20 and 70 meters. At Green Point, the
increase in salinity was not great for the first 24 days, but thereafter
there was a marked increase of salinity at all levels but never with ap-
preciable gradients below the surface layer. At Hood Point, the heavier
AN OCEANOGRAPHIC MODEL OF PUGET SOUND 695
water appeared to flow into a bottom layer below 100 meters before
there was any effect above that level. After 38 days, however, there
was more saline water at all layers with a relatively uniform gradient
existing between 10 and 80 meters. At this time, the salinity below 100
meters had practically attained its maximum value. Equilibrium con-
ditions were closely approached by the end of 89 days.
It is seen from these results that, with the exception of Green Point,
significant salinity gradients will appear at all depths for appreciable
lengths of time following a change in source salinity; whereas a change
in river runoff will only have a minor and local effect. Qualitatively,
these results are borne out in the prototype. Characteristically, the Pu-
get Sound basins flush most rapidly in the fall when the Strait of Juan
de Fuca water, the salinity source, is of its greatest annual density, and
not during periods of maximum local runoff.
MopEt APPLICATIONS
The model has been operated for groups of engineers interested in
sewage disposal and pollution studies with good success. The insertion
of dye at present or proposed sewage outfalls gives a clear and rapid pic-
ture of the pollution likely to occur at various localities. The value
of a tidal model for this type of study may readily be appreciated when
the ease with which a particular mass or type of water may be “tagged”’
by a suitable dye is seen. The transport and rate of dispersion of the
water mass may be observed directly and continuously followed over
large areas for the equivalent of long periods in the prototype.
The model has proven useful support of a fisheries-biology study
concerned with the drift of fish eggs. “The drift of dye in the model
correlated with field observations clarified the movement of the eggs,
location of the hatching areas, and distribution of the larvae. Con-
tinuous observations were made for a period representing many days in
the prototype. Thus a detailed picture could be obtained from field
observations which were somewhat scattered with respect to both loca-
tion and time.
In planning field work, the model can be set to operate for the
anticipated period of the cruise. The probable water structure and
movement can be observed, and locations selected for most efficiently
collecting the desired information. In an area of mixed tides, a tidal
model which can be set to duplicate tides for a specific calendar period
is a distinct advantage.
The model has proven to be a valuable teaching aid. The processes
occurring in nature over a large area are readily observable, and a
clear synoptic picture of their interrelations is thus obtained. Examples
696 EIGHTH PACIFIC SCIENCE CONGRESS
of various features of inshore circulation can be pointed out and ex-
plained simply and easily. ‘The student can use the model to obtain
data corresponding to field measurements, and then work it up in the
usual manner.
SUMMARY AND CONCLUSIONS
An hydraulic model of Puget Sound has been built and tested under
various conditions. Equipment for controlling and measuring the
oceanographic variables has been designed and put into satisfactory
operation. Prototype tide and current are well represented by those in
the model. It has been demonstrated that density structure similar to
that in nature can be obtained by proper control of operating condi-
tions, but no detailed comparison has been made between prototype
and model structure under corresponding conditions.
697
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695 EIGHTH PACIFIC SCIENCE CONGRESS
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AN OCEANOGRAPHIC MODEL OF PUGET
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AN OCEANOGRAPHIC MODEL OF PUGET SOUND 7038
Comparison of Equilibrium Salinity Structures
Average river flows
Skagit river flooding at 50,000 cfs, --------
PT, JEFFERSON CAMANO HEAD GREEN POINT
100
1SO
200
FIGURE 8
Change in Salinity Structure Resulting from
DECREASE
in Source Salinity
ELAPSED TIME
(1) Start (2) 45 Days (3) 101 Days (4.) 166 Days
PT JEFFERSON CAMANO HEAD GREEN POINT HOOD PCINT
Salinity %o 20 30 20 30 20 30 20 30
i]
50
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FIGURE 9
EIGHTH PACIFIC SCIENCE CONGRESS
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DAILY SEAWATER OBSERVATIONS ON THE PACIFIC
COAST OF CANADA
By H. J. HOL.isTER
Pacific Oceanographic Group
Nanaimo, B.C., Canada
A programme of daily observations of surface seawater temperatures
and salinities has been in progress on the Pacific Coast of Canada since
1933. Fourteen sampling stations are located at strategic positions (Fig.
1) along the extensive coastline so that each station monitors the condi-
tions in a natural region. The majority of the stations are located at
lighthouses (Fig. 2) where the lightkeeper carries out the duties of
water sampling in addition to his regular duties.
The procedure and apparatus are quite simple. The observer takes
the daily sample during the last hour of the rising tide occurring in the
daytime. A two-ounce medicine bottle is inserted in clips attached to
a wooden rod and lowered to a depth of three feet. The bottle is stop-
pered with a rubber cork on the end of a guided brass rod, and the sam-
ple is obtained by pulling out the stopper. Fastened alongside of the
bottle clips is a brass protective case containing a mercury Fahrenheit
thermometer. The whole apparatus is left immersed in the sea for two
minutes, then the stopper is replaced in the bottle and the rod raised.
The observer immediately reads the temperature and records it on a
dated label already placed on the sample bottle, which he then seals
with a wax-impregnated cork. Date, time of sampling and water tem-
perature observed are also recorded on a data record sheet.
The bottles are packed in cases of one hundred, and are shipped
to the central laboratory where the salinities are determined by a modi-
fied Mohr titration. The water temperatures and salinities are pub-
lished in annual volumes entitled, “Observations of Seawater Tempera-
ture and Salinity on the Pacific Coast of Canada.” ‘These data provide
a continuous record of the changes occurring in the marine climate of
the waters surrounding each station, and provide a backlog of informa-
tion which can be used to illustrate the year to year fluctuations in the
overall coastal oceanographic conditions. ‘These data might provide
the only clue in determining why the fishery in a certain coastal region
changed in volume from one year to the next.
705
706 EIGHTH PACIFIC SCIENCE CONGRESS
CLIMATE IN THE SEA
Seasons can be defined in the sea (Fig. 3) just as they are in the
atmosphere. Summer is that period when water temperatures are at a
maximum, which in the northern hemisphere occurs in the month of
August. Winter is the season when they are at a minimum, usually
December and January. Spring and autumn are the transition periods
from these two extremes. “The extremes and durations of these marine
seasons differ from year to year due to changing atmospheric conditions.
That is why these daily seawater records are so valuable. It is only by
reference to these records that the scientist is able to measure just how
great the annual variation has been. The daily seawater records will
show these annual changes more clearly than meteorological data be-
cause they reflect the combined effect of the varying atmospheric factors
of solar insolation, wind, rainfall, and land drainage.
Along such an extensive coastline as British Columbia, there are
several different types of oceanic regions. The locations of the water
sampling stations have been chosen so that the various types of regions
are all being recorded by daily surface observations. The annual range
of seawater temperature varies from station to station and this differ-
ence in annual temperature range is a criterion to the type of region
being observed. For instance, in Figure 4, Langara shows an annual
temperature range of 10°F, typical of an exposed open ocean region;
Kains shows a slightly higher annual range of 11°F, typical of an exposed
coastal region; Entrance shows a high annual range of 18°F, typical of
a protected coastal region; and Race Rocks shows a low annual range
of 6°F, typical of a region of great turbulence.
The annual salinity cycles observed at the various seawater sampling
stations (Fig. 4) are typical of three climatic regions. Summer salinity
maxima (Kains) are due to coastal upwelling and low summer precipi-
tation with little subsequent fresh water runoff. “The degree of coastal
upwelling is governed chiefly by the force and duration of winds blow-
ing offshore during the summer. In these latitudes, the winds are never
in a continuous steady state, and assessment of the degree of upwelling
from wind data alone would be quite difficult. Observation of the ef-
fect of these winds as indicated by the surface salinities is a much easier
matter.
Fresh water runoff from the many large rivers that drain into the
Canadian Pacific area is at a maximum in the summer because of the
melting of snow at the sources of the rivers far inland. This effect is
demonstrated by a summer salinity minimum at all the sampling sta-
tions situated near the mainland coast, such as Entrance Island. Here
again, measurement of the combined effect of the various atmospheric
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 707
factors creating this summer freshet, such as solar insolation, previous
winter snowfall, and wind, is easily monitored by the simple observation
of the changes in seawater salinity.
The third type of marine climatic region is that where the annual
salinity variation is very slight. On the Canadian Pacific Coast, this
can be further divided into two sub-classes, one where the station is
exposed to the deep open ocean (Langara) and the other where the
station is located in a turbulent water-way (Race Rocks). There is very
little annual salinity variation at Langara, but the records will demon-
strate the year to year changes caused by major alterations in the system
of offshore circulation (Figs. 6 and 7). To measure these large scale
circulation patterns is a major oceanographic undertaking, and is some-
times not possible owing to lack of facilities. But an idea of the extent
of the change in unsurveyed periods can be estimated from surface sea-
water observations made at the exposed ocean stations.
The annual salinity changes observed in turbulent sea-ways serve
to measure the extent of mixing of the more saline deep waters with
the less saline surface waters. “The Fraser River flows into Georgia
Strait and is eventually discharged to the ocean past Race Rocks in the
Juan de Fuca Strait. It may be noted that there is a slight drop in sa-
linity at Race Rocks during the month of August, following a large
decrease in salinity during June and July at Entrance Island, further
north in the Strait of Georgia. Comparison of the records in these two
stations which are subject to the influence of the one major river, shows
the difference of the degree of this influence in adjacent and connecting
regions.
Combining both water temperatures and salinity records, it is pos-
sible to measure the annual seasonal fluctuations in the oceanic climate.
This is a simpler method than trying to evaluate the more variable at-
mospheric phenomena from meteorological records and applying their
effects on the oceanic state.
MONITORING OCEANOGRAPHIC CONDITIONS
The oceanographer determines the changes that occur in the sea
from year to year and from season to season by conducting detailed
examinations of the various properties of sea water, chiefly the tempera-
ture and salinity. On the Pacific Coast of Canada there are several
general types of oceanic regions, each demonstrating a typical pattern
of seasonal variation in the properties of temperature and salinity. This
pattern is similar from year to year, but the extent and duration of the
change from one season to another varies. The seawater sampling sta-
tions have been located in such a way that they sample the ocean waters
708 EIGHTH PACIFIC SCIENCE CONGRESS
of these typical regions. Once the oceanographic conditions of an area
have been determined for each season of the year by means of oceano-
graphic surveys, it is only necessary to refer to the daily seawater records
to recognize annual changes in the properties of the water. Thus, Lan-
gara and Cape St. James record the exposed open ocean regions; Triple,
Sandspit, Ivory, Entrance, Texada, Departure Bay and East Point record
the protected coastal regions; Kains and Amphitrite record the exposed
coastal regions; and Pine, Cape Mudge and Race Rocks record the tur-
bulent sea-ways. ‘The Pacific coastline of Canada is so extensive that
these typical oceanic regions occur in widely separated locations where
the determining factors of meteorological conditions, fresh water runoff,
and tide might be quite different in magnitude. This is especially
true of the region of Georgia Strait, where the extensive variation in.
local geographic conditions creates several sub-classes of oceanic regions.
The oceanography of the Georgia Strait (Fig. 1) is dominated by
the fresh water discharge from the Fraser River. This fresh water flows
over the surface of the strait, mixing all the time with the underlying
salt water as it flows in a northward direction along the eastern shores.
Once these surface waters reach the vicinity of Cape Mudge they turn
south and flow along the western shore and finally empty into the Juan
de Fuca Strait (Figs. 5 and 6). The passage of this brackish upper zone
of water can be marked by the changes in surface salinities at Entrance
Island, Cape Mudge, East Point, and finally Race Rocks. The diluting
effects of the Fraser River discharge and the degree of mixing with the
deeper salt water can be measured by the salinity changes observed at
Entrance Island (Fig. 7). A series of oceanographic surveys extended
over a period of two years have determined the circulation patterns in
Georgia Strait for every month of the year. It is now only necessary
to refer to the annual changes in salinity at Entrance Island in order
to predict the occurrence and duration of any of the seasonal patterns
previously determined by the oceanographic surveys.
Another application of these daily seawater observations to observ-
ing oceanographic conditions is in the “offshore” area. During August
of 1950 and 1951 oceanographic surveys were made of the northeast
Pacific Ocean extending to 500 miles offshore. In 1950 (Fig. 8) there
were three clouds of warm water (60°F) lying in a band parallel to the
coast with colder water on either side. In 1951 (Fig. 9) the warm water
covered the southwest part of the area surveyed. ‘The surface water
temperature increased steadily to seaward and decreased to the north.
An examination of the August mean surface water temperatures observed
at four seawater sampling stations located on the coast showed that the
irregular 1950 ‘“‘offshore” surface conditions were associated with an ir-
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 709
regular sequence of monthly mean temperatures at these stations for
this year (Fig. 10). The more regular 1951 “offshore” conditions were
associated with a regular decrease of monthly mean temperatures at
these same stations from Amphitrite in the south to Langara in the north.
Although the oceanographic surveys were conducted during the months
of August and July, the sequence of coastal temperatures for each year
showed the same pattern as that following in August; so it should be
possible to predict changes in the oceanographic state of the ‘‘offshore”’
waters from an examination of the surface temperature trends exhibited
by these daily seawater stations.
During the summer of 1950 there was an excellent tuna fishery off
the Canadian Pacific Coast. In the following summer, 1951, very few
tuna were caught in the same area. Tuna are a warm water fish and
their occurrence in Canadian Pacific waters could be due to the warm
water cloud circulation observed in the August 1950 oceanographic sur-
vey previously mentioned (Fig. 8). A correlation between the varia-
ble “offshore” temperature distribution of 1950 and 1951 and the sea-
water temperatures measured at coastal sampling stations has been pos-
tulated. ‘The value of this correlation will be immeasurable if it can be
extended to serve as a means of prediction of the availability of tuna
to the fisheries in this marginal region.
DAILY SEAWATER OBSERVATIONS ASSIST FISHERIES INVESTIGATIONS
Fisheries biologists are finding significant correlations between
changing ocean conditions and fluctuations in the availability of fish.
These studies have only been instituted in recent years because of the
inadequate catch statistics for previous years. Ihe scope of these studies
covers the effect of ocean environment on spawning populations, juve-
nile fish and adult migrations. It has been demonstrated that the daily
seawater observations can be used to monitor the changes in the con-
ditions of the sea in the several climatic regions on the Pacific Coast.
It is now only a short step to the next logical phase of using these daily
observations to assist in the prediction of fish availability.
Investigations have already been made into the possibilities of a
correlation between the July sequence of coastal station temperatures
and the offshore tuna fishery, with quite encouraging results. The tuna
fishery for 1952 was as unsuccessful as that for 1951, and an examination
of the July and August mean temperatures for the same four coastal
stations showed a similar characteristic of a regularly decreasing tem-
perature from south to north. It was not possible to make an offshore
710 EIGHTH PACIFIC SCIENCE CONGRESS
oceanographic survey during the summer of 1952 to determine the tem-
perature distribution pattern, so these daily records from the coastal
sampling stations were doubly important because they are the only cri-
teria of what type of surface temperature distribution must have existed
in these offshore waters during the summer of 1952.
Considerable research has been done on the relationship of seawater
conditions in Hecate Strait, as monitored by Triple Island station, and
fluctuations in the strength of lemon-sole year classes in the fishery
in that area. Researchers have found that when the water temperatures
during January and February are lower than normal there is an in-
crease in the availability of fish in April and May. Further studies are
progressing to determine why the relationship exists.
An association has been found between availability of the cohoe
salmon in the fishery off the west coast of Vancouver Island and the
salinities of the coastal waters as observed at Amphitrite and Kains
sampling stations. It appears that higher than normal inshore salinities
during the summer months provide better cohoe fishing for the inshore
boats and poor fishing for the offshore boats. Studies concerning the
ocean environment of salmon and their feeding habits are being con-
tinued to determine the reason for this correlation.
BIBLIOGRAPHY
HOLLISTER, H. J. Daily sea water observations in Georgia Strait. Fish. Res.
Bd. Canada, Prog. Rep. Pac., No. 91, December, 1949.
Daily sea water observations along the west coast of Vancouver
Island. Jbid., No. 86, April, 1951.
Daily sea water observations in northern British Columbia wa-
ters. Ibid., No. 91, June, 1952.
Daily sea water observations along the central British Columbia
coast. Ibid., No. 94, March, 19538.
PIcKARD, G. L. and D. C. McLrEop. Seasonal variation of temperature and
salinity of the surface waters of the British Columbia coast. J. Fish.
Res. Bd. Canada, 10, p. 125, 1953.
TULLY, J. P. Weather and the ocean. Fish. Res. Bd. Canada, Prog. Rep.
Pac., No. 26, December, 1935.
Report on dynamic studies off the Canadian Pacific coast, 1936.
Trans. Amer. Geo. Union, 18, p. 228, 1937.
Seasons in the sea. Fish. Res. Bd. Canada, Prog. Rep. Pac.,
No. 32, June, 1937.
Some relations between meteorology and coast gradient currents
off the Pacific Coast of North America. Trans. Amer. Geo. Union, 19,
p. 176, 1938.
—————. Seasonal cycles in the sea. Fish. Res. Bd. Canada, Prog. Rep.
Pac., No. 85, December, 1950.
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 711
TULLY, J. P. Climate in the coastal seas of British Columbia. Jbid., No. 90,
March, 1952.
TULLY, J. P. and E. BERTRAM BENNETT. Project “Offshore,” coastal tem-
peratures and tuma. Ibid., No. 92, October, 1952.
WALDICHUK, M. Oceanography of the Strait of Georgia. I. Salinity distri-
bution. Fish. Res. Bd. Canada, Prog. Rep. Pac., No. 93, December, 1952.
ANONYMOUS. Observations of sea water temperature and salinity on the Paci-
fic Coast of Canada. Pacific Oceanographic Group, Pacific Biological
Station, Nanaimo, B.C., Volumes I to XII, 1914 to 1952.
712 EIGHTH PACIFIC SCIENCE CONGRESS
ILLUSTRATIONS
Fic. 1—Chart showing the location of daily seawater stations on the
Pacifie Coast of Canada.
Fic. 2.—An aerial photo of Triple Island lightstation. (Photo courtesy
R.C.A.F.)
Fic. 3.—Seasonal variations of the water and air temperatures at Kains
Island, Quatsino Sound, for the year 1935.
Fic. 4.-Average seawater temperatures and salinities at four typical
sampling stations for 15 years, 1934-1949.
Fic. 5.—Distribution of salinity at two yards depth in Georgia Strait.
February 1950.
Fic. 6.—Distribution of salinity at two yards depth in Georgia Strait.
June 1950.
Fic. 7.—Seasonal variation in Fraser River discharge and surface sali-
nity at Entrance Island station, 1950.
Fic. 8.—Surface temperature distribution, north-east Pacific Ocean,
August 1950.
Fic. 9.—Surface temperature distribution, north-east Pacific Ocean,
August 1951.
Fic. 10.—The sequence of monthly average temperatures along the ocean
coast of British Columbia.
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 713
Long. 126° W
Cope St. James
QUEEN
CHARLOTTE
SOUND
Koins:|.
FIGURE 1
Location of Stations Making
Daily Seawater Observations
Stations ore Underlined
@.9- Langero L
COLUMBIA
. a ads
Cope Mud:
EIGHTH PACIFIC SCIENCE CONGRESS
714
Z ANNI
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 715
JAN FEB MAR APR MAY JUNE JULY AUG SEPT ocT NOV DEC
Po a Ulnar ae as ea
\ i : OBSERVERS
Jo Hy CE.CARVER
By eka nea se SLNEAVE 60°F
RSSaG : t Wath AN
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ib ;
, AL : i
aw ; AQ
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Na x
Was Vi & A
Ig . SUMMER- | ae
.: : WINTER
20 ene
BY
40°
QUATSINO STATION
WEST COAST
VANCOUVER ISLAND
'935
ener
FIGURE 3
* LANGARA
Ww Ut
PONHDONS
F M A My Ju vy Au S ON
oO
NNN Nw Ww
On
Too
SYN LWY3dW3L
ALINIAVWS
RACE ROCKS
|
lence oa
1
SALINITY
W
a
=
a
4
WW
a
=
WwW
(SF
do
FIGURE 4
T1é EIGHTH PACIFIC SCIENCE CONGRESS
(Ss
w
w
re
OEPTH .
10 20
°
[gee falies ! n ]
Secele of Olistence
FIGURE 5
SEAWATER OBSERVATIONS ON THE PACIFIC COAST OF CANADA 717
ACIWOnNGe 27
7 We
AS
DEPYW - FEET
10 zo
°
[gee files l 4 ]
Scale of Distence
FIGURE 6
400
cu.FT./SEC. X 1000
200
DISCHARGE
100 |
EIGHTH PACIFIC SCIENCE CONGRESS
30
FRASER RIVER DISCHARGE
at
HOPE , B.C.
JAN. FEB. MAR. APR. MA
25
20
F244 synoptic surveys
SALINITY %e
Y JUNE JULY AUG. SEPT. OCT.
1950
NOV. DEC.
FIGURE 7
bs —_
PROJECT OFFSHORE
CRUISE | |
(HG& CEDARWOOD)
PACIFIC OCEANOGRAPHIC GROUP
NANAIMO , B.C.
& S
0,
iv)
AUGUST
SCALE OF DISTANCE
qe hwics 60 wo | |
1
as"
1
‘o7"
"SURFACE
"SEAWATER TEMPERATURES (F)___
1950
LOts1SS° WOOT iy 12955 SA ee ae 2 Tee
FIGURE 8
OBSERVATIONS ON THE PACIFIC COAST OF CANADA 719
SEAWATER
SEAWATER TEMPERATURES (°F)
PROJECT OFFSHORE
CRUISE i, 1988
(KMS CEDARWOOD)
PACIFIC OCEANOGRAPHIC GROUP
NANAIMO, BC
SURFACE
AUGUST 1951
SCALE OF DISTANCE
SEA MILES 30 100
eee ll
1
ws?
LOMG 133" WEST
FIGURE 9
1950 JULY 1951
50°F 55 50 55 60
Langora
C St James
Kains
Amphitrite
J
AUGUST
50°F 50 55 60
55
Taney San ihs|
Langara .
Cc St James
Kains
Amphitrite
FIGURE 10
fe!
Eb
ay
A STUDY OF LOCAL VARIABILITY IN MARINE SEDIMENTS *
By RicHarp G. BADER
Department of Oceanography, University of Washington
Seattle 5, Washington, U.S.A.
INTRODUCTION
The sampling problem involved in obtaining any natural sample is
often exceedingly complex and has received much consideration in the
literature. In the process of obtaining any one sediment sample by
means of a coring tube or other sampling device, only an exceedingly
minute portion of the sea bottom is sampled. In a strict sense any single
sample is merely representative of the exact spot sampled. Unless the
process of sampling continues systematically in this and adjacent areas,
radial extrapolation from the sample is subject to great error, with any
single sample being representative of only itself. ‘The introduction of
this limitation on problems of sedimentation or sedimentary environ-
mental studies, whether they be physical, chemical, or biological, pre-
sents a serious handicap. In order to proceed with any sedimentary
research it is necessary to know the limitations of the samples obtained
and to understand, at least to some degree, the existing local variations
and the probabilities for such variations.
The purpose of this paper is to briefly present some of the initial
results concerning a problem of sampling marine sediments in the region
of Puget Sound, in the State of Washington. The information to date
consists of the data from a particle size analysis of the bottom sediments
obtained along an east-west traverse of Puget Sound, about 12 miles
north of the city of Seattle.
REGIONAL DESCRIPTION
Puget Sound is a pre-existent valley system which has been partially
drowned by the sea. It is one of the deepest salt water basins in the
United States. The mid-channel bottom area exceeds 900 feet in depth
in some localities. Depths of 600 or more feet below sea level are usually
encountered in the channel portions of the Sound. Except for local
areas, the shore slopes and underwater slopes are steep; inclines of 25
degrees are common.
* This work was supported by the Office of Naval Research under Contract Ne. N8onr-
520/III, Project NR 083-012, with the Department of Oceanography, University of Washington,
Seattle 5, Washington.
721
W22, EIGHTH PACIFIC SCIENCE CONGRESS
The topography of the Puget Sound area is due primarily to glacial
action by a lobe of the Cordillerian ice sheet. The shore line is bordered
by deposits of clay, sand, gravel and till, reminiscent of the glacial con-
trol. These glacier-derived sediments often form shore line cliffs 200
or more feet high.
Glacial till is a prominent source of sediments in Puget Sound and
may become a part of the marine sediment in various ways. (1) The
slopes may be in part composed of glacial deposits “in situ”. (2) The
ercsion of cliffs and beaches will also be a supply of glacial sediments.
(3) the streams are imposed on glacial till and will transport this ma-
terial to the marine environment. (4) Slumping of the cliffs, which are
composed of glacial deposits, will add to the marine sediments.
Chemically and mechanically weathered material from the basement
rocks of the Cascade and Olympic Mountains contributes to the sedi-
ments as they are carried to the Sound by the numerous streams and
rivers. Volcanics, from direct dust-falls and from inland erosion, pro-
bably account for some sediment supply in the Sound.
In the area of sampling (Fig. 1), between President Point on the
west shore and Point Wells on the east, the bottom configuration is
analogous to the steep shore bluffs. The eastern underwater slope is
generally steep and continuous with a value of 1:3.5 from a single
break at about 20 feet below sea level to the base of the slope which
is approximately 700 feet below sea level. A few localities have slopes
of 1:1. The western slope is not as continuous, being divided into areas
with different slope angles. Some portions are exceedingly steep with
values as great as 1:3, others have gradual slopes with an average value
of 1:15. This suggests that bathymetrically the two slopes are different
(See Fig. 3). In this region the slope areas account for about one-hall
of the total Sound width of 35.7 miles. The mid-channel region, repre-
senting the remaining one-half, is relatively flat with a maximum relief
of about 75 feet.
METHOD OF SAMPLING AND ANALYSIS
Initiai examination of core samples from Puget Sound indicated
that extreme variability in particle size existed. It was suspected that
this variability occurred over exceedingly small horizontal distances. In
order to study the variability both horizontally as well as vertically, over
small horizontal distances, a device was designed to simultaneously ob-
tain three cores spaced in a triangular pattern, | foot apart (Fig. 2).
The cores obtained by this method were cut into sections 4 cm. in length
from the surface down. Thus three approximately equal surface samples
and three samples for every subsequent 4 cm. in depth were obtained
LOCAL VARIABILITY IN MARINE SEDIMENTS U2
for analysis. Some 60 locations on a traverse across Puget Sound have
been sampled, making available for comparison the data obtained from
the analysis of 180 cores. (Fig. 3 gives the location of these samples.)
The sampling of approximately 18 to 20 locations in the mid-channel
and on the near shore slopes is planned for the near future.
The vertical sectioning of the cores in the manner just described
yielded well over 500 individual samples. Each sample was analyzed
for particle size by standard methods. The material courser than 1/16
mm. in diameter was sieved mechanically, separating it into standard
fractions. “The material finer than 1/16 mm., previously separated from
the sample by wet sieving through a 1/16 mm. sieve, was submitted to a
pipette analysis for size determination. This latter method is based
upon Stokes Law; that is upon the settling velocities of spheres of a
given radius suspended in a fluid of known viscosity.
Since this study deals with the variation in the results obtained
in the size analysis of adjacent core samples, it is essential to know the
analysis error. The standard method briefly described above satisfies
this condition in allowing an impartial duplicate analysis of the same
sample to be run under essentially standard laboratory conditions. When
the reproducibility of the results are known, it is possible to differentiate
between inconsistencies due to analysis and the actual variation between
samples.
Duplicate analysis of 20 samples indicated that the analysis error
was very small, with an average reproducibility for any one size deter-
mination of +0.2 percent. There was very little divergence from this
average, with only about 20 percent exceeding the average by a factor
of 2. The probabilities are thus in favor of actual sample variation ac-
counting for percentage differences between adjacent samples which ex-
ceed +0.4 percent.
INITIAL RESULTS
In order to present a summation of the results obtained, the east-
west traverse of the Sound has been divided into three general areas.
The eastern and western slope area from sea level down to about 500
feet below sea level represents one division. ‘he lower portion of both
slopes, from about 500 feet below sea level to the base of the slopes and
adjacent channel areas, represents the second division. The last division
is the mid-channel region.
The following table presents some of the differences in grade size
percentages between the samples from the three cores obtained simul-
taneously at one Jocation. The percent differences shown are thus in-
724 EIGHTH PACIFIC SCIENCE CONGRESS
dicative of variations in particle size distribution from samples only
one foot apart.
DIFFERENCES IN GRADE SIZE PERCENTAGES *
SLOPE BASE OF SLOPE MID-CHANNEL
(ee MAX MIN AVER. MAX. MIN. AVER MAX. MIN. AVER
% % Ve Nyce Zanes % a %e
>4 1 Al 5 — See <1
42 2 <1 1 <1 193e Ste 1980
Fic. 2.—Variations of the annual mean sea-level (solid curves) and their
progressive trends (dashed curves).
ANNUAL MEAN SEA LEVEL ALONG THE JAPANESE COASTS 741
FIGURE 2 (continuation)
|
i
ww)
EIGHTH PACIFIC SCIENCE CONGRESS
Des hn
Kushimoto
3) aD
Tonoura
Masamori Miyazaki me
FIGURE 3
SUBMARINE CANYON INVESTIGATIONS
By Francis P. SHEPARD
Scripps Institution of Oceanography
University of California, La Jolla, California, U.S.A.
[Published: Proceedings of the Eighth Pacific Science Congress, vol.
IIA (Geology and Geophysics and Meteorology), p. 820-826
(1956) ]
SURFACE TEMPERATURE AND SALINITY IN THE
SOUTHWEST PACIFIC OCEAN
By D. M. Garner
Oceanographic Observatory
Department of Scientific and Industrial Research, Wellington
New Zealand
ABSTRACT
From material recently collected, the hydrology of surface waters
in seas around New Zealand is discussed in a series of papers to be pub-
lished in forthcoming issues of the New Zealand Journal of Science and
Technology. ‘The disposition of mean monthly sea surface isotherms
is described over an area from the East Australian coast to the 180th
meridian between latitudes 20°S and 46°S. Differences between these
patterns for individual years and the charts showing mean monthly
isotherms published by the United Kingdom Meteorological Office,
are defined and discussed in terms of climatological factors. “These pat-
terns are also discussed in terms of oceanic circulation and, in part-
icular, features of the flow of subtropical water southwards off the
east coasts of Australia and New Zealand are described. With the aid of
thermograph records obtained on transTasman and tropical commercial
routes, the fine temperature detail associated with the water masses
(defined by the mean patterns), and their boundaries, are described.
Similar records, obtained in New Zealand coastal waters, establish the
relation between water circulation and bottom topography, and define
areas of upwelling, and the distribution of subtropical, subantarctic,
and coastal water types.
To a more limited degree, salinity in the various water masses
defined by the temperature patterns is also discussed.
743
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SECULAR TRENDS AT EAST AUSTRALIAN COASTAL
STATIONS: 1942-1952
By D. J. Roctrorp
Marine Biological Laboratory, Cronulla
N. S. W., Australia
I. INTRODUCTION
A phenomenon of extreme importance to the oceanographer work-
ing upon fisheries problems is the occurrence of long term trends in
hydrological conditions at any region.
As part of its coastal oceanographical programme the C.S.I.R.O.
Fisheries Division has, since 1942, maintained monthly to fortnightly
sampling at a number of stations situated some five miles offshore in
about 60-70 metres of water. (Fig. 1.)
At each of these stations samples for temperature, chlorinity, dis-
solved O,, pH, inorganic phosphates, organic phosphorus and _ nitrate
nitrogen have been collected at 10-metre depth intervals to 50 metres.
Within the time limits of this paper it is proposed to demonstrate
long term trends in hydrological properties at a number of these sta-
tions, and to discuss possible causes of such trends.
II. DATA AND METHODS
The data and the methods used in their collection and analysis
have been given in Oceanographical Station Lists of the C.S.I.R.O.
Vols. 4 and 14.
In order to simplify the presentation of the trends, the data have
been divided into a summer period, October to April inclusive, and
a winter period, May to September, on the basis of the annual tem-
perature cycle in these waters. During the summer period the water
temperature increases or remains at a stationary maximum value,
whilst during the winter it decreases or remains stationary at a minimal
value.
The vertical water column at each station has been subdivided into
a surface zone, in which sampling at 0, 10 and 20 metres depth are
included and a bottom zone in which sampling at 30, 40 and 50 metres
depth are included. Surface or bottom values of any hydrological prop-
erty are thus the A.M. of the 0, 10 and 20 or the 30, 40 and 50 metre
values respectively.
745
746 EIGHTH PACIFIC SCIENCE CONGRESS
III. S—EcULAR TRENDS AT THE Port STEPHENS, PorT HACKING AND
MariA ISLAND COASTAL STATIONS
In order to illustrate the latitudinal spread of the trends exhibited
by east Australian coastal waters, and also to provide as long a time
span as possible, only data from the three earliest established coastal
stations in New South Wales and ‘Tasmania will be considered in this
section.
Fig. 2 shows how the mean summer and winter surface and bottom
nutrient conditions at the Port Hacking station have varied over the
period 1943 to 1952. There is clear evidence of a gradual rise in in-
organic and total phosphorus for both surface and bottom layers, with
little difference between winter and summer conditions. Nitrate ni-
trogen values have also risen during the same period, but only in the
bottom layers.
Fig. 3 demonstrates clearly the gradual decrease in Cl°/,, as-
sociated with an increase in the rainfall at the Port Hacking coastal
station during the same period. However, it is clear that the summer
bottom Cl°/,, was decreasing well in advance of the 1948 increase in
summer rainfall. At the Port Stephens coastal station (Fig. 4) there
is evidence of an increase in inorganic and total phosphorus from 1945
to 1950, but after that year the values have remained steady. It is to
be noted, however, that the magnitude of the increase is much less than
at the Port Hacking station. Moreover, nitrate values have decreased,
except for the rather inexplicable increase in the bottom winter waters.
At the same station the Cl°/,, of surface waters has been greatly af-
fected by land runoff (Fig. 5). However, it is important to note that
the Cl°/,. of the summer bottom waters has varied little during the
period.
Off Maria Island (Fig. 6), the inorganic phosphates have increased
since 1946 to a maximum in 1950, but have remained at this level since
that year. The total phosphorus increase parallels that for inorganic
phosphate. There appears to have been little change in the nitrate
nitrogen of these waters during the same period.
The Cl°/,,. of these waters (Fig. 7) has increased at a steady rate
since 1947 and this is true of both summer and winter periods. The
decrease in rainfall particularly during the winter period is apparent.
It is clear then that at each of these three coastal stations at dif-
ferent latitudes along east Australia, there has been an increase in the
phosphate content, both in the inorganic and organic form, over the
past 7-10 years. The nitrate nitrogen has increased only at the Port
Hacking station and has decreased at the other two stations.
SECULAR TRENDS AT £. AUSTRALIAN COASTAL. STATIONS :1942-52 747
For the New South Wales stations, the decrease in chlorinity of the
surface waters particularly has been associated with increases in rain-
fall, but on the other hand, at the Maria Island station there has been
an increase in C]°/,, accompanied by a decrease in rainfall.
IV. Factors oF PossisLtE IMPORTANCE IN THE GENESIS
OF THESE TRENDS
(a) Riverine dilution and nutrient enrichment of coastal waters.
The parallelism between surface Cl°/,, and rainfall trends at the
three stations considered in the previous section, suggests that land
drainage can greatly affect the Cl°/,, of these coastal waters.
The considerable scatter evident in the plotting of the relationship
between rainfall and coastal surface Cl°/,, in east Australian waters
(Fig. 8), is not unexpected, because of the varying time lag between
rainfall and its effect as riverine discharge on coastal Cl°/,, and also
because of the varying depth to which such discharges are mixed into
the coastal water structure. However, it is clear that surface waters are
diluted by riverine discharge with increasing effectiveness as the rain-
fall increases. Moreover, there is clear evidence of the existence of two
principal surface water masses, a New South Wales above 37°S and an
eastern Tasmanian below 37°S. Is it possible that these riverine dis-
charges could vary the phosphate levels of these coastal waters to the
extent that has been experienced at the three stations discussed in
Section III?
In Fig. 9, the relationship between inorganic phosphates and
Cl¢/,, at the Port Hacking station is shown. It is clear that surface
and bottom waters exhibit a different Cl°/,.-phosphate relationship.
inpthnesuniace Wayery a decrease im) Glo/>5 from 19:70 to 19.40%,
is accompanied by a rise in inorganic phosphates of 6ug P/L. Assuming
that the decrease in Cl°/,, is due to land drainage and that the rise
in inorganic phosphates has been wholly an effect of such riverine dis-
charges, then the phosphate concentration in the discharge would have
to be about 400yg P/L. ‘This figure is about 10 times greater than the
maximum phosphate level in coastal rivers of the phosphate rich north-
ern New South Wales region and about 40 times greater than the rivers
immediately adjoining Port Hacking.
In the bottom waters the decrease in Cl°/,, from 19.70 to 19.55 is
paralleled by a rise in inorganic phosphates of 9ng P/L. This would
imply a phosphate concentration of 1200,g¢ P/L in the diluting water,
which phosphate concentration is quite impossible.
748 EIGHTH PACIFIC SCIENCE CONGRESS
It is apparent therefore that whilst land drainage can modify the
Cl°/,, structure of coastal waters, its role in the gradual increase in
phosphate levels at coastal stations since 1945 cannot be a direct one.
(b) Lateral movement of slope waters into the coastal region.
During 1940-42 F.R.V. “Warreen’”’ was able to sample simultaneous
coastal and shelf stations at frequent intervals off Port Hacking. Fig.
10 shows the relationship between inorganic phosphates and Cl°/,, for
slope waters and Fig. 11 for the bottom coastal waters sampled during
this period. The regression line for the slope data above 10ug/L PO,P
has been calculated and superimposed on the coastal water diagram.
The coastal data fits this regression line fairly well and it is highly
probable that slope waters of varying depths have periodically invaded
these coastal regions during this period.
Since that time, the systematic collection of data at the Port Hack-
ing coastal station has revealed that these slope water invasions of the
coastal region are a common feature of the summer period, particularly
during the period of high vertical stability. “These slope waters are
comparatively rich in phosphates with lower Cl°/,., temperature and
dissolved O, than the coastal bottom waters. Could the rise in in-
organic phosphates and the decrease in Cl°/,, in the bottom waters at
the Port Hacking station during 1943-1952 be an effect of more frequent
invasion and more effective assimilation of such slope waters into the
structure of coastal waters?
Whilst lack of information about the dynamical continuity between
slope and coastal regions makes the examination of such a possibility
very difficult, there are certain significant features in the trend curves
at the Port Hacking station which favour such a theory.
Referring again to Fig. 3, it can be seen that the mean summer
bottom temperatures have decreased fairly consistently from 1943 to
1949, and risen rather rapidly since that year. This trend is paralleled
by the Cl°/,,. of these waters and, whilst the surface dilution of these
waters during the 1949 period and onward, may have contributed in
some measure to the later portion of this trend, the fact that this de-
crease commenced in 1944 would indicate some more fundamental cause
of the phenomenon. Assuming then that the decrease in summer bottom
temperature and chlorinity has been little influenced by the rainfall
cycles during the period, there seems good evidence to support the
theory of more effective assimilation of low temperatures and chlorinity
slope waters into the structure of the Port Hacking bottom coastal waters
during 1943-1949.
(c) Increase in phosphate content of slope waters.
SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS :1942-52 749
Fig. 12 shows the relationship between total phosphorus and oxy-
gen saturation values of the Port Hacking summer bottom waters during
1943-1952.
By differentiating the data into years, it is possible to see clearly
that these bottom waters have changed their O,-total phosphorus rela-
tionship quite considerably during the period.
To better illustrate this, two envelopes have been entered, one
labelled A, containing a majority of the data subsequent to and the
other labelled B, prior to that year. At any given oxygen saturation
level it is clear that the total phosphorus content has increased over the
period. Unfortunately one cannot assume from this that the parent
slope waters have also changed their total phosphorus and dissolved O,
content in a similar fashion at the depth of origin of these coastal in-
trusions. “There would, however be no reason to suppose that the east
Australian slope waters would not undergo long term changes in hydro-
logical properties, and it is quite possible that an increase in the nu-
trient level of the parent slope waters themselves has contributed to
these coastal water trends.
(d) Replacement of local coastal waters by a foreign water mass of
higher nutrient content.
Along the east Tasmanian coast the evidence from coastal observa-
tions suggests that lateral movement of deep offshore waters into
coastal regions is extremely rare, largely because it is suspected that a
slope current is only weakly developed. One cannot assume therefore
that the same processes have contributed to the secular trends at the
Maria Island station, as have been considered responsible in more
northern latitudes. It is significant too that the rise in phosphates and
total phosphorus has been accompanied by an increase in Cl°/,, and
temperature during the winter period, particularly from 1947 to 1951.
On the evidence it was considered probable that in this region the
secular changes were due to a gradual displacement of the original east
Tasmanian water mass of 1945 by a new water mass of higher Cl°/ 9,
temperature and nutrient content.
In Fig. 13 the total phosphorus-chlorinity relationship of the mean
summer bottom data for east Australian coastal stations is shown. It
seems clear from this slide that all of the data can be developed by
mixing between three primary water masses with distinct total phos-
phorus-Cl°/,, relationship. If we examine the chlorinity-temperature
relationship, Fig. 14, three primary water masses can be distinguished.
It is possible to identify a New South Wales coastal and an east Tasma-
nian coastal water mass on their temperature, chlorinity, total phos-
phorus relationships, but the genesis of the third with low temperature
750 EIGHTH PACIFIC SCIENCE CONGRESS
and chlorinity, associated with high total phosphorus characteristics is
difficult to decide exactly, although such characteristics are more typi-
cal of deeper offshore waters of New South Wales than of east Tasma-
nia.
Without sufficient knowledge of the dynamics of the New South
Wales ‘Tasman Sea, however, it is impossible to demonstrate how such
a water mass could have influenced the Tasmanian coastal region.
V. METEOROLOGICAL AND DyNAMICAL CHANGES ASSOCIATED
WITH THESE TRENDS
If we accept the proposition that the secular trends at the Port
Hacking coastal station are due in large measure to variations in the
amount of slope water influence, then a study of the possible factors
controlling such slope water variation might eventually enable the
oceanographer to predict by study of the variation in the principal con-
trolling factors, oceanographical conditions in future seasons. For the
past 10 years the C.S.I.R.O. Fisheries Division has been studying the
monthly and annual variations in mean sea level at a station representa-
tive of coastal conditions off Port Hacking.
If we examine the mean summer and winter mean sea levels varia-
tions at this station during the period 1942-1952, Fig. 15, the existence
of a secular trend is evident. Moreover, the magnitude of the cycle has
been much greater during the summer than the winter period. ‘The
period of minimum summer mean sea levels irom 1946 to 1949, cor-
responds to the period of lowest mean summer bottom temperatures
at the Port Hacking station. ‘There is evidence from the New South
Wales coastal station of the development of a counter current flowing
north, at distances of about 5 miles offshore, during the later part of
the summer, ‘The high mean sea levels normally experienced in March-
April are considered to be an effect of this current along the coast.
Presumably then during seasons when this counter current is strongly
developed, the intrusion of slope waters is retarded because the isen-
tropic layers are tilted down towards the coast and oppose the latera!
movement of dee) slope waters into the coastal region.
In Fig. 16 the relationship between mean monthly sea level and
bottom temperatures at the Port Hacking station during December over
the period 1942-1952 is shown. For those years when high sea levels
prevailed during December and are indicative according to the theory
outlined above of weak slope water influence, the mean monthly bottom
temperatures are higher.
It seems clear then that the ultimate answer to both variation in
slope water intrusion and the coastal mean sea level at the Port Hacking
SECULAR TRENDS AT E. AUSTRALIAN COASTAL. STATIONS :1942-52 751
station is linked with the variation in the development of this counter
current. However, it has not been possible as yet to show any con-
sistent relationship between the variation in this counter current and
corresponding variation in the direction or strength of coastal winds.
It is possible that wind conditions over the Tasman Sea proper may be
more influential in this regard but scarcity of data prevents such an
analysis being made.
VI. Discussion
In studying the coastal hydrology of the east Australian region
with its comparatively narrow shelf and well-developed offshore current
system, the extreme variability of the coastal environment and the major
effects of the offshore current on such variation, are evident. ‘This
paper serves to illustrate another longer term variation, which is im-
portant to the fisheries of the region and which has had very wide-
spread effects.
It is obvious, however, that to advance beyond the mere descrip-
tion of coastal events, and of their probable genesis, to a more com-
plete and perhaps useful stage, requires the simultaneous collection of
information upon the dynamics and hydrological structure of the off-
shore in addition to the onshore regions. Moreover, it is clear that the
elucidation of the causes for long term fluctuations in east Australian
coastal conditions requires persistent and intensive investigation not
only of the coastal hydrology but also of the associated estuaries and
their flood contribution, as well as of the meteorological elements, par-
ticularly wind and rainfall, which enter into these cycles.
EIGHTH PACIFIC SCIENCE CONGRESS
PORT STEPHENS COASTAL STATION
Latitude: 32° 43’ S.
SUMMER PERIOD
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
October
’45-April
’46-April
»47—-April
’48-April
’49-April
’*b0—April
*51-April
’52-April
’45—-April
’46—-A pril
?47—April
’A8—April
’49-April
’50-April
»51—April
’52-April
*45-April
’*46-April
?47-April
’A8—April
749—April
50—April
51—April
’52-April
PORT STEPHENS COASTAL STATION
"46
"AT
"A8
"49
D0
*ol
D2
08
"46
"AT
"48
"AQ
’b0
ol
702
d3
’A6
"AT
"48
"49
50
’O1
"52
D3
TEMP.
Cl °/v0
0—-25 m. Mean
19.51
TO eTO
19.54
19.22
19.53
21.64
18.62
20.26
25-50
17.47
17.35
17.91
17.89
16.99
19.31
17.52
18.10
m.
19.27
19.60
19.63
19.62
19.52
19.52
19.63
19.56
Mean Column
19.59
19.60
19.63
19.64
19.61
19.61
19.62
19.58
Longitude: 152° 18’ E.
PO:P
Column
or co O1 00 Or 1 bY CO
9
8
13
8
15
ff
13
14
0-50 m. Mean Column
18.49
18.53
18.63
18.56
18.26
20.73
18.07
19.18
Latitude: 32° 43’ S.
WINTER PERIOD
May—September
May-—September
May—September
May—September
May-—September
May-—September
May-—September
May-—September
"45
"46
"AT
48
*49
’b0
"51
"D2
TEMP.
19.48
19.60
19.63
19.63
19.57
19.57
19.63
19.57
Cl "/s0
10.5
9.5
TeTAL P.
13.5
10.5
18
11
23.5
13.5
16
16
NO:N
Longitude: 152° 18’ E.
PO:P
0-25 m. Mean Column
(17.52) (19.52)
16.89 19.65
17.98 19.61
(18.45) (19.63)
18.05 19.36
18.21 19.34
(18.50) (19.59)
19.07
19.62
(2)
3
(4)
(5)
9
8
(6)
6
ToTAL P.
(5)
5
(8)
(12)
16
13
(18)
15
NO.N
100
(105)
101
o
80
89
88
it
93
89
82
83
87
94
94
87
96
(97)
92
SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS :1942-52 755
25-50 m. Mean Column
May-September ’°45 (17.88) (19.68) (8) (14) (56) (79)
May-September ’46 16.48 19.67 2 5 19 96
May-September °47 (17.85) (19.63) (6) (11) (51) (87)
May-September ’48 (18.15) (19.62) (4) (12) (3) (100)
May-—September ’49 17.90 19.51 10 15 45 91
May—September ’50 18.07 19.56 11 15 54 86
May-September ’51 (17.87) (19.68) (8) (14) (95) (95)
May-September ’52 18.42 19.63 8 iy 21 95
0-50 m. Mean Column
May—September 745 (17.48) (19.60) (2.5) (9.5) (35) (88)
May-September 746 16.69 19.66 2.5 5 15 97
May—September 747 (17.92) (19.62) (5) (9.5) (40) (91)
May-—September ’48 (18.30) (19.68) (4.5) (12) (3) (100)
May-September ’49 17.98 19.44 9.5 15.5 31 93
May-September ’50 18.14 19.45 9.5 14 42 91
May-September 751 (18.19) (19.61) (7) (16) (48) (96)
May-September °52 18.75 19.63 a 16 15 96
PORT HACKING COASTAL STATION
Latitude: 34° 05'S. Longitude: 151° 13’ E.
SUMMER PERIOD TEMP. Cl °/o0 PO:P TOTAL P. NO:N 02%
0-25 m. Mean Column
October ’42-April °43 19.86 19.67 1 — 5 97
October ’43-April °44 19.45 19.67 1 4 7 97
October ’44-April 45 19.37 19.65 1 4 4 96
October ’45-April ’46 19.54 19.60 4 10 17 96
October ’46—-April ’47 18.69 19.64 3 7 15 97
October ’47—-April ’48 19.18 19.60 6 13 6 98
October ’48-April ’49 18.91 19.61 6 12 10 98
Qetober °49-April ’50 19.19 19.43 9 20 19 95
October ’50-April 751 20.85 19.44 5 15 6 98
October ’51—April 752 19.54 19.64 4 15 10 100
October ’5Z-April 753 20.14 19:59 5 15 5 99
25-50 m. Mean Column
October °42—April 743 18.10 19.63 5 — 22 83
October *?438—April ’44 17.85 19.69 4 8 19 90
October *44—-April 745 17.87 19.64 3 uf 18 90
October ’45-April 746 17.00 19.60 9 15 46 84
October ’46-April ’47 16.92 19.62 6 11 35 88
October *47-April ’48 17.30 19.58 12 19 53 88
Qctober ’48-April ’49 16.75 19.57 10 15 35 88
October ’49-April 50 17.50 19.58 14 21 62 83
October ’50-April °51 18.98 19.54 9 21 34 89
October *51—-April 52 17.56 19.63 13 20 44 89
October °52-April 753 17.74 19.58 13 21 40 87
754 EIGHTH PACIFIC SCIENCE CONGRESS
0-50 m. Mean Column
October ’42—-April 743 18.98 19.65 3 — 15 90
October ’43—April ’44 18.65 19.68 2.5 6 1133 94
October ’44—April ’45 18.62 19.65 2 55) 11 93
October ’45-April ’46 18.27 19.60 6.5 WPA 32 90
October ’46—April ’47 17.81 19.63 4.5 i) 25 93
October ’47—April ’48 18.24 19.59 9 16 30 93
October ’48—-April ’49 17.83 19.59 8 13.5 23 93
October ’49—-April ’50 18.35 19.48 Tales) 20.5 40 94
October ’50—April 51 19.82 19.49 uf 18 20 93
October ’51—-April ’52 18.50 19.64 10 We) Pal 95
October ’52-April 753 18.94 19.59 9 18 28 93
PORT HACKING COASTAL STATION
Latitude: 34° 05'S. Longitude: 151° 13’ E.
WINTER PERIOD TEMP. Cl °/00 PO.P TotaL P. NO:N 02%
0-25 m. Mean Column
May-September 743 15.89 19.62 5 10 15 97
May-September 744 16.84 19.70 2 9 9 97
May-—September 745 17.99 19.57 3 9 21 92
May-—September 746 16.98 19.67 3 6 15 95
May-September 747 16.86 19.65 5 ult 31 95
May-—September ’48 16.59 19.62 8 EZ, 8 99
May-September ’49 17.67 19.638 9 14 9 96
May-—September ’50 17.90 19.44 7 19 IY 99
May-—September 751 aL S74 19.51 8 18 16 hel
May—September 752 17.53 19.47 10 16 21 89
25-50 m. Mean Column
May-September 743 15.74 19.69 6 11 18 92
May—September 744 16.38 19.67 4 10 7 93
May-September 745 16.54 19.58 8 15 52 82
May-September ’46 16.72 19.67 4 Uf 27 94
May-—September 747 16.17 19.638 6 10 44 sit
May-September 748 16.01 19.61 9 16 20 96
May-—September ’49 17.04 19.63 9 16 30 91
May-September ’50 17.36 19.52 11 21 48 92
May-September ’51 WAL 19.56 10 20 33 90
May-—September 752 16.80 UG) by 7 15 22 54 89
0-50 m. Mean Column
May-—September 743 15.79 19.66 5.5 10.5 7 95
May—September 744 16.61 19.69 3 9.5 13 95
May-—September ’45 OAL 19.58 5.5 12 37 87
May-—September ’46 16.85 1OLGi 3.5 6.5 21 95
May-September ’47 16.52 19.64 5.5 10.5 38 93
May—September ’48 16.30 19.62 8.5 14 14 98
SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS :1942-52 755
May-—September 49 17.36 19.63 9 15 20 94
May-—September ’50 17.63 19.48 9 20 33 96
May-—September 751 17.50 19.54 9 19 25 94
May—September 752 IU ell'g 19.52 1255 18 38 89
MARIA ISLAND COASTAL STATION
Latitude: 42° 36'S. Longitude: 148° 16’ E.
SUMMER PERIOD TEMP. Cl °/o0 PO:P Tota. P. NO3N 02%
0-25 m. Mean Column
October ’44-April *45 (12.51) (19.34) — — (12) —
October ’45-April ’46 (14.59) (19.34) (4) (6) (13) (97)
October ’46—-April ’47 13.78 19.31 4 6 1% 101
October ’47—April 748 14.14 19.39 9 13 12 97
October *48—-April ’49 13.26 19.37 8 i 5 92
October ’49-April 750 (13.91) (19.387) (11) (22) (7) (100)
October ’50—April 751 14.64 19.40 8 22 7 (95)
October °51—April 752 14.31 19.54 11 (14) 10 (85)
October °52-April °53 14.65 19.40 8 Wi 1 101
25-50 m. Mean Column
October ’44-April ’45 (12.18) (19.384) — — (3) —
October ’45—-April 746 (14.14) (19.35) (5) (9) (22) (94)
October ’46—April ’47 fi Seto 19.30 5 iq 24 99
October *47—April ’48 13.59 19.39 10 14 15 92
October ’48—April 749 12.80 19.41 8 13 6 95
October ’49-April 750 (12.98) (19.387) (12) (15) (13) (94)
October ’50—April 751 14.16 19.44 9 au 4 90
October ’51—April 752 13.89 19.51 10 (16) 12 85
October ’52-April 753 13.59 19.41 11 21 25 (91)
0-50 m. Mean Column
October ’44-April 745 (12.35) (19.84) — — (8) ==
October ’45—-April 746 (14.87) (19.35) (4.5) (7.5) (18) (96)
October ’46—April 747 13.45 19.31 4.5 6.5 18 100
October ’47—April 748 13.87 19.389 975, 13.5 14 95
October ’48—April 749 13.03 19.39 8 12.5 6 94
October ’49-April ’50 (13.42) (19.87) (11.5) (18.5) (10) (97)
October ’50—April 751 14.40 19.42 8.5 20.5 6 (93)
October *51—April 752 14.10 ORD Ss 10.5 15 11 (85)
October ’52—April 753 14,12 19.41 9.5 19 19 (96)
MARIA ISLAND COASTAL STATION
Latitude: 42° 36'S. Longitude: 148° 16’ E.
WINTER PERIOD TEMP. Cl °/o0 PO:P OLA Ebr NO3N 02%
0-25 m. Mean Column
May-—September ’45 (13.00) (19.46) — — (7) (97)
May—September 746 LEST 19.33 7 9 36 $9
; 6
May-—September
May-—September
May-—September
May—September
May—September
May—September
May—September
May—September
May-—September
May-—September
May—September
May-—September
May—September
May-—September
May-September
May-—September
May—September
May—September
May—September
May—September
May-—September
May-—September
EIGHTH PACIFIC SCIENCE CONGRESS
"47
°48
’49
*b0
"D1
52
*45
*46
"AT
48
"49
*B0
51
D2
"45
"A6
*47
°48
749
"60
*51
"52
12.44 19.32 6
11.43 19.35 11
(12.46) (19.39) (11)
13.31 19.44 10
13.76 (19.48) (9)
12.19 19.47 11
25-50 m. Mean Column
(12.95) (19.45)
Tiss TO) ay a my
IAS OS Es
nA OB)
(12.47) (19.89) (12)
WO OL)
ES (Oss) ©
#12125) 19.47, 10
0-50 m. Mean Column
(12.98) (19.46) —
11.48 19.34 7
1246" 149-33 6.5
YD = IGAYR cata
(12.47) (19.89) (11.5)
e103) VLOG 9.5
13.75 (19.47) (8)
12.22 1947 10.5
16
14
(17)
ul)
(22)
13
8.5
15
14
(19)
17.5
(17)
11.5
SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS 21942-52 757
rn
BRISBANES .
COFFS HARBOUR
PORT MACQUARIE
> PORT STEPHENS
BOTANY BA
Y
PORT HACKING
LLADULLA
ae ws
sr PORT
PHILLIP
@ ST. HELENS PT.
FIGURE 1
EIGHTH PACIFIC SCIENCE CONGRESS
758
NITRATE NITROGEN
TOTAL PHOSPHATE FP
INORGANIC PHOSPHATE FP
1947
1948
’ iF . ®
NUMBER OF STATIONS
FIGURE 2
SECULAR TRENDS AT E,. AUSTRALIAN COASTAL STATIONS :1942-52 759
RAINFALL ANOMALY
FIGURE 3
CHLORINITY °%,,
WATER TEMPERATURE (°C.).
°
NUMBER OF STATIONS
SNOILWLS 40 WIGANN
r
60
INORGANIC PHOSPHATE P
EIGHTH PACIFIC SCIENCE CONGRESS
TOTAL PHOSPHATE P NITRATE NITROGEN
$z
uw
°
- FIGURE 4
ty4
AUSTRALIAN COASTAL STATIONS :1942-52 761
SECULAR TRENDS AT E.
RAINFALL ANOMALY
CHLORINITY °/,,
WAT_4 TEMPERATURE (°C)
1948
‘
NUMBER OF STATIONS
1949
7
FIGURE 5
NITRATE NITROGEN
TOTAL PHOSPHATE P
INORGANIC PHOSPHATE P
so
1948 1949
4 5) ’
s
NUMBER OF STATIONS
1952
FIGURE 6
SNOILVLS 40 WIBWAN
AO2
WATER TEMPERATURE (TC.
261
EIGHTH PACIFIC SCIENCE CONGRESS
CHLORINITY °/..
RAINFALL ANOMALY
is: $
t
\ a
' a
° a
a yy
£4
li
UE
‘i
FIGURE 7
SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS : 1942-52
+]
(oy)
6
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EIGHTH PACIFIC SCIENCE CONGRESS
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SECULAR TRENDS AT E, AUSTRALIAN COASTAL STATIONS :1942-52 765
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EIGHTH PACIFIC SCIENCE CONGRESS
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SECULAR TRENDS AT E. AUSTRALIAN COASTAL STATIONS: 1942-52 767
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EIGHTH PACIFIC SCIENCE CONGRESS
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FIGURE 15
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EIGHTH PACIFIC SCIENCE CONGRESS
PORT HACKING (DECEMBER),
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MEAN SEA LEVEL. (Inches).
FIGURE 16
40
RECENT DEVELOPMENTS IN TIDAL AND TIDAL
CURRENT MEASUREMENTS *
U.S. CoAsT AND GEODETIC SURVEY
CURRENT MEASURING EQUIPMENT
During World War IJ, when a large part of its personnel and
equipment had been transferred to the Armed Forces, the U.S. Coast
and Geodetic Survey, in an effort to meet both military and civilian
requirements, devised several new instruments and procedures. One
of the most interesting of these is a radio current meter known as the
Roberts Radio Current Meter after its designer Capt. E. B. Roberts,
now Chief of the Division of Geophysics of the Bureau. The design
includes both the meter and a special buoy to support the meter and
house the radio transmitter.
As often happens after field trials, the first design of this equip-
ment was found to have some features capable of being improved.
These improvements have been embodied in a revised design known as
Model II. However, Model I instruments are still being used with
satisfactory results.
Equipment losses in congested harbor areas are likely to be high.
Buoys with attached equipment sometimes disappear without trace and
cannot be found by dragging. More often buoys are rammed by pass-
ing craft and set adrift. When found, if the meters are still attached,
they are usually badly damaged. Frequently the meter suspension cable
has been cut and all meters lost. Losses can be minimized to some
extent by publication of operations in local and weekly Notices to
Mariners. From time to time, it becomes necessary to replace equip-
ment lost in operation, and successful bidders have found it desirable
to make minor changes during construction. These have not changed
the basic design, but unless made by the same manufacturer, parts are
not always interchangeable.
The introduction of this meter represented such a radical change
in standard methods for the determination of tidal current velocities
that it was necessary to prepare a special operating manual for it. This
manual has been revised periodically as improvements in equipment
* Contribution from the U.S. Coast and Geodetic Survey, Department of Commerce, Wash-
ington, D.C., U.S.A.
Presented by Capt. Andres O. Hizon, Director of the Bureau of Coast and Geodetic Sur-
vey, Republic of the Philippines.
a
CU EIGHTH PACIFIC SCIENCE CONGRESS
and methods have occurred. ‘The latest revision was made in early
1952. It will be revised again to include improved procedures devel-
oped during the 1952-53 seasons.
At present, research is underway toward improved designs for the
transmitter and chronograph. Considerable work has been done on
the design of a low-velocity highly sensitive meter for use on the bot-
tom. Work is also in progress on an automatic recording system for
these meters.
FIELD METHODS
As indicated earlier, this meter is a wartime development, con-
ceived as the solution of the problem of economical and rapid deter-
mination of surface current velocities of interest to marine navigators.
The laborious and time-consuming methods involving the anchoring
of vessels or barges on current stations could no longer be employed
for lack of men and floating equipment. The Roberts Radio Current
Meter provided an economical and relatively easy method for making
current observations from surveying vessels engaged in hydrographic
or other surveys within radio range of the buoy transmitters. The
design of this equipment was based on the concept of single-meter oper-
ation. ‘To permit satisfactory handling from small craft, weights were
kept to a minimum. At first, normal operating procedure consisted of
streaming a buoy with one meter attached—usually at some level 12 to
40 feet below the surface. At receiving stations, whether ashore or
afloat, it is necessary to tune manually receivers to the frequency of
each transmitter. This limits observations in radio-congested areas to
six or seven meters for a single receiving station, as six or more clear,
unobstructed frequency channels are difficult to find. Interruptions
in transmission make records difficult to process—oftentimes worthless.
For marine transportation, surface current velocities are of para-
mount interest, and the Roberts Radio Current Meter was used at
first to determine these. Because of its light weight it tends to lift
in proportion to the strength of the current in velocities greater than
about 2 knots. A tendency to sheer is noticeable in velocities of 3
knots. A leader was devised for attachment to the buoy anchor cable
to obviate these tendencies. It was found desirable to use this leader
regardless of the velocity because it causes the meter to pivot about a
point of the anchor cable and produces more consistent results in cur-
rent direction measurements.
Although the buoy, as designed, has a strong planing lift, it must
be carefully streamed to insure satisfactory operation in strong cur-
rents. The lightest cable of adequate strength must be used. It has
also been found desirable to attach buoy wings at the sides and bow.
DEVELOPMENTS IN TIDAL & TIDAL CURRENT MEASUREMENTS 773
The Roberts meter lends itself to economical operation for obser-
vation at one or two stations simultaneously with large-scale surveying
activities in the same general area. Activities of this nature are usually
carried on by vessels maintaining continuous radio watches. Radio per-
sonnel can monitor and receive the meter transmissions without greatly
interrupting their normal routine. Since the advent of electronic ship-
positioning methods, it is sometimes desirable to have electronic shore-
station personnel receive meter returns from isolated current stations
within range. This method is not as desirable as the ship receiving
method unless electronic shore-station personnel are increased sufficient-
ly to permit the usual “on the spot” tabulations.
For short-period observations, it has been found desirable on oc-
casion to use the Roberts meter without the radio link. In practice a
small vessel, or launch, is anchored on station and the meter hoisted
in and out in the manner normally employed when using non-record-
ing meters. The meter is connected electrically to a tape chronograph,
ut without the radio receiver and amplifier.
REVISED FIELD METHODS
Earlier methods have been revised and new components introduced
which have made it possible to more than double the former rate of
receiving. In the early days each meter required a separate radio fre-
quency and transmitter. Monitoring, receiving, and tabulating records
from six or seven transmitters were about all the receiving-station per-
sonnel could manage in one 30-minute observation period. Last year
a timing device, known as the “Sequence Switch,” was designed and
developed in the Bureau. Since then it has become standard practice
to suspend three meters from one buoy. By inserting the sequence
switch in the meter circuits returns from each meter are coded and
transmitted over one frequency. It is now possible to receive returns
from 18 meters in one 30-minute period. This switch is illustrated and
described briefly in the 1952 revised operating manual. An _ article
concerning the switch appeared in the Surveying and Mapping News
section of the 1952 September-October issue of the Military Engineer.
With the development of the three-meter suspension method it be-
came necessary to discard the leaders. The added weight of meters
and connections plus a 30- to 50-pound lead, or cast iron “sinker’’ below
the meters prevents any great amount of lift in moderate velocities.
Care must be exercised in attaching the two extra meters to prevent
“twist” in electrical cables—otherwise they may not stream freely with
the current. If this does occur, it can first be detected in the direction
data, as, obviously any prolonged indication of directions normal to
TTA EIGHTH PACIFIC SCIENCE CONGRESS
channel axes must be erroneous. Multiple meter suspension was first
used with 80-inch buoys. They do not have enough reserve buoyancy
to carry the extra weight satisfactorily in strong currents. One-hundred-
twenty-inch buoys are now being used with much better results. Their
use also makes it possible to employ heavier “sinkers’” and heavier ball-
bearing swivels between meters.
For routine current work in the past, when velocities at levels
other than surface were desired, observations were made at two-tenths,
five-tenths, and eight-tenths of the depth at the station. In an effort to
determine the behavior throughout the depth, observations have been
made at varying intervals from surface to bottom. ‘The larger num-
ber have been made at levels of 6 to 12 feet below the surface, at mid-
depth, and at a minimum of about 3 feet above the bottom, irrespective
of the rise and fall of the tide. The Woods Hole Oceanographic In-
stitution has devised an experimental mounting for use in shoal water
where velocities are desired at fixed levels within 1.5 to 3.0 feet from
the bottom.
EQUIPMENT AVAILABILITY AND CosT
The Roberts Radio Current Meter and equipment is not patented.
It is currently being used by severai federal agencies and one or two
oceanographic institutions. One English instrument maker has ob-
tained a set of specifications and has, it is presumed, produced instru-
ments for Admiralty use. ‘Those used in the United States have been
produced by three different “low-bidding” instrument makers, none of
whom have produced them for general sales. ‘The radio transmitters
and sequence switches have been procured in much the same manner.
The major items of special equipment necessary to operate a cur-
rent survey party using a launch and shore-based receiving station are
listed below, with the approximate total cost.
[EB UOy sO sGlhi ier aces eee 6 @ $760.00 — $ 4,560.00
2. Roberts Radio Current Meter 18 @ 550.00 — 10,000.00
3. Radio transmitter for buoy .. 6 @ 400.00 — 2,400.00
4. Radio receiver for shore station 1 @ 400.00 — 400.00
5. Chronograph, tape recording . 1 @ 675.00 — 675.00
6. Voice radio, for launch and
Shoremstablon ue ane alien 2 @ 750.00 — 1,500.00
7 Ground tackle; per) DUOy nae) 40 @ 200.00 — _ 1,200.00
SE SEQUENCE mS WiC Iain ere a ee ae 6 @ 90.00 — 540.00
Total $21,275.00
DEVELOPMENTS IN TIDAL & TIDAL CURRENT MEASUREMENTS 1775
From this it can be seen that the equipment required for one cur-
rent party represents a modest investment.
‘TIDE AND CURRENT PROGRAM
Early in 1951 the Bureau embarked on a tide and current program
in domestic waters on a scale it had never before attempted. Several
vessels were assigned this duty exclusively. ‘Two of these were large
enough to provide suitable berthing and working spaces for all per-
sonnel employed. Others were not, and it became necessary to estab-
lish self-contained receiving stations ashore. In protected waters the
employment of the shore-station method permits the use of medium-
sized launches suitably equipped to handle the buoys, but otherwise re-
quiring few men. A shore station can be operated quite satisfactorily
by nine men. One of these is the supervisor and relief and the other
eight are divided into four watches of two men each. The launch and
station combination makes for very economical operation, if or when
overhead costs of larger vessel operation are considered.
Simultaneous observations of tides and currents have been under-
taken as regular routine in this program. Normally, about one-third
of the special tide stations in each area are established and operated
for a period of 12 consecutive months. ‘They are equipped with stand-
ard recording gages. The remainder are equipped with portable gages
which are operated for 2 consecutive months. While the tides and cur-
rents are being observed, all tide station bench marks and tide staffs
are interconnected by closed loops of first-order levels. “This provides
the means of relating the tide planes determined independently at each
station. When the observations at the tide stations have been cor-
rected to a 19-year mean through comparison with a reference station,
the results show the variation of the different tide planes throughout
the survey area as referred to a common datum. Also through com-
bination of simultaneous tide observations and the interconnecting level
lines, the pattern of gradient variation between stations throughout the
tidal cycle can be established.
fe
i Teles
ON THE MINIMUM OXYGEN LAYER IN THE
NORTH PACIFIC OCEAN
By TAkEo KAWAMOTO
Kobe Marine Observatory, Japan
Oxygen in the sea is supplied by contact with the atmosphere and
by photosynthesis. On the other hand, dissolved oxygen is consumed
by the respiration of marine organisms and the reduction of bacterial
action or the reducing agents of both inorganic or organic matters dis-
solved in water. Thus the oxygen contents in sea water are always af-
fected by the reactions of general oxidation and reduction taking place
im the sea. Besides the oxygen content in the sea are influenced by
the mixing with other waters. Therefore, if there is no supply of oxy-
gen in sea water, the dissolved oxygen will be diminished gradually.
Then, if we observed a water mass which contained low oxygen value
in the intermediate waters, we generally consider that the water mass
had taken a long run and many times before reaching that region.
So when we discuss the property of the water mass or its movement
in ocean, it is important and interesting to know the distribution of
dissolved oxygen in sea waters. Though the causes of the variations
in the dissolved oxygen content are not explained completely, but by
tracing the distribution of poor oxygen layer in the ocean some aspects
of the oceanic general circulation in the intermediate waters will be
given.
We have much interest in the oxygen minimum layer observed
at the depths between 400 and 1000 meters in the North Pacific Ocean.
This paper is an attempt to obtain the general aspects of the general
oceanic circulation in the intermediate waters in the North Pacific
Ocean by the distribution of poor oxygen layer. Figures show the hori-
zontal distribution of the dissolved oxygen at 250, 500 and 1000-meter
layers, respectively.
These oceanographical data were obtained from the following re-
ports:
The “Carnegie” in 1928, 1929.
The “Soyo Maru” in 1933, 1934, 1935.
The “E. W. Scripps” in 1938, 1939, 1940, 1941.
The U. S..S. “Bushnell” in 1939.
The “H. M. Smith” in 1950.
The “Tenyo Maru” in 1951.
UE
773 EIGHTH PACIFIC SCIENCE CONGRESS
From the figure (500-meter layer), we can recognise a remarkable
poor oxygen region on the east side of the North Pacific Ocean. Espe-
cially off California, we can find even no oxygen at that layer; how-
ever, on the west side—Kuroshio region—the content being abundant
comparatively. And in the Oyashio region the minimum layer is at
shallower depth. This means that in the southern region off Kurile
Islands there occurred upwelling of the intermediate water of the North
Pacific Ocean.
‘The writer will, in conclusion, show the general circulation of the
intermediate water of the North Pacific Ocean as follows:
(1) In the region off California the intermediate water upwells and
runs westward following the equatorial current.
(2) Before reaching the Kuroshio region it mixes with other waters
along the route.
(3) A part of the above mentioned current takes the easterly course
sinking to a lower layer.
(4) The other part of the current flows northward to the Kurile
Islands region and runs eastward along Aleutian Islands to places off
North America and California.
MINIMUM OXYGEN LAYER IN THE NORTH PACIFIC OCEAN 779
150 180 150 ‘ 120
150 180 150 120
eww DY ON THE PROPERIY, OF DHE COASHAL WATER:
AROUND HACHIJO ISLANDS
By Yasuo Miyake, Y. SuGiuRA and K. KAMEDA
Meteorological Research Institute, Tokyo, Japan
It is interesting to study how the property of the ocean water is
affected by the presence of a tiny island in the far-off sea, and to what
extent the coastal water of such an island is changed by land water
pouring into the sea. Since the land water contains more nutrient
matter than the offshore water, it may contribute more or less to the
biological productivity around the island. Accordingly, a study of this
problem will give also a basic knowledge for the coastal fisheries and
the growth of sea weeds near the island.
For such a program, the chemical properties of the coastal sur-
face water around Hachijo Island (33°05’N, 139°48’E) were studied
in July, 1951, December, 1952, and in October, 1953.
Land waters of the island were also chemically investigated during
the observation periods. In summer (from 13 to 28 July, 1951), the
surface water temperature varied from 23.7°C to 27.4°C, pH of sea
water averaged 8.3 and the mean chlorinity was 18.75°/o,. The con-
centrations of most of the nutrients in this season were so low that am-
monia-N was less than 3g atoms per liter, nitrite-N was also less than
0.05u.g atoms per liter, and phosphate-P could be found only in traces.
Only silicate-Si was present in an appreciable amount. The amount
was about 10g atoms per liter in the offshore water, but increased
as the shore was approached until a quantity of 20 to 70y,g atoms per
liter was present. In winter (from 6 to 14 Dec., 1952), the water tem-
perature of the surface was about 20°C and the chlorinity averaged
19.02°/,,, which was comparatively higher than in summer. The
amounts of the nutrient salts were also larger. Nitrite-N and nitrate-N
were contained from 0.05 to 0.70 and from 1 to 100,g atoms per liter
respectively. Phosphate-P was from 0.05 to 4.0ug atoms per liter. Sil-
icate-Si was from 10 to 70ug atoms per liter. The distribution patterns
of these compounds around the island were like that of the chlorinity
shown in Figure 1. As shown in Figure 1, the effect of the island on
the ocean water was greater in the region from the eastern to the
southern coast owing to the different amount of the outflowing land
water as well as to the direction of the current. The effect of the ocean
781
782 EIGHTH PACIFIC SCIENCE CONGRESS
current is seen clearly on the southern coast where the shadow of the
current is formed.
The daily variations in the concentrations of some chemical sub-
stances were observed at a fixed point A in Figure 1.
It was found that the chlorinity change showed a good correlation
with the tide, increasing and decreasing in the same direction as the
elevation of the water level (Fig. 2). The relation between the silicate
content and the chlorinity is almost linear as shown in Figure 3. Using
these facts, we can calculate the mixing ratio of ocean water and land
water. The result of calculation shows that the rate of mixing in the
surface water at the distance of 100 m. from the coast line is about 25%
in winter and the effect of land water seems to extend as far as to about
5 km. from the land.
The diurnal variation of the dissolved oxygen content is shown in
Figure +. It is maximum at about 14 h. and minimal in the early morn-
ing. Such a type of variation resembling somewhat that of air tem-
perature may be regarded as a normal one as pointed out by one
(Miyake 1) of the present authors previously.
In summer the range of variation is greater than in winter, as the
population of living matter and the intensity of the sunshine are larger
in summer.
Since most of nutrient matter near the shore is supplied from the
land, the chemical analysis of land water is also necessary.
There are a number of wells, small springs and a few streamlets in
the island. These may be classified into two groups from a chemical
point of view. The first group (A) of waters contains much chloride
and nutrient matter while the second one (B) contains a considerably
lesser amount.
It is interesting to note that the content of the silicate-Si in land
water was comparatively larger in summer than in winter. In compar-
ing the land water with regard to the nutrient matter, it is seen that
the first group has a remarkably richer silicate and nitrate content than
the second.
The average concentrations of both groups are shown in Table I.
TABLE I
AMM.-N NITRITE-N NITRATE-N PHOSPHATE-P SILICATE-SI CHLORINITY
ug at/L pe at/L pe at/L pe at/L pe at/L %
A 0.0 0.00 ees 0.5 180 0.02
B
3.0 0.05 95. lef 180 0.60
1Y. MIYAKE: Geophys. Mag., 16, (1948), 66-70.
PROPERTY OF THE COASTAL WATER AROUND HACHIJO ISLANDS 783
[<>] Ss
= oe
} 2
SH SoS
2 oO
B Sa
~ =
33°10" B
Fig. 1.—The distribution of the chlorinity around Hachijo Islands, Dec., 1952.
EIGHTH PACIFIC SCIENCE CONGRESS
784
-INS Td}BVM 01
SULISIP [BOIQIOA B SE Gq
IU ck 9G Vi. cE of - 3
eso 2°
‘Aqyjgol vw worz sory
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9 y ¢ be 22 O8
03° eT
19
00° 6T
%
Ost
002
wo
PROPERTY OF THE COASTAL WATER AROUND HACHIJO ISLANDS 785
°% 19 06°8T
“APULLOTYO BY} pus Ig 97¥dI[IS 94} Jo JUNOWe ayy UdEMJaq UOTWBIOL euUL—'e “DIY
OL°ST Og9°S8T Og°ST OT°ST 06° LT OL°L4T §=OG° ALT
1/° 48-377 ts
I
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fons
KIGHTH PACIFIC SCIENCE CONGRESS
—@---@— pDec., 1952
% —@—_o— July, 1951
Summer
ec/litre
ae Rome.
4 ea
ws :
5.0 “Oe --@--o 4
Winter
4.0 Summer
Bo Oe Ley LAN OS Ie BON Bey BAN ee yA Glen Ou Dis
Fic. 4.—The diurnal] variation of the dissolved oxygen.
ON THE OCEANOGRAPHICAL CONDITIONS OF THE SEA
NEAR EEE EEX Dy POET alba 7 oI aN: INT aE
NORTH PACIFIC OCEAN
By M. Nakano, M. Koizumi and J. FUKUOKA
Central Meteorological Observatory of Japan, Tokyo, Japan
1. INTRODUCTION
The variations of water temperature, chlorinity, etc. in deep layers
of the ocean have not yet been made clear owing to the scarcity of con-
tinuous data of serial oceanographical observations taken at a fixed
point for a long time. However, several years ago, ocean weather sta-
tions were set up, and serial oceanographical observations are being
made without interruption.
In Japan, the first ocean weather station was established at the point
beso Ne iin Ene North Pacific: Ocean, im October 1947, andthe
second one at the point 135°E, 29°N, in June 1949. ‘The former station
is now named “Extra,” and the latter “Tango.” The data of meteoro-
logical and oceanographical observations at these fixed points are pub-
lished in “The Results of Marine Meteorological and Oceanographical
Observations,” a quarterly bulletin of the Central Meteorological Ob-
servatory of Japan.
At these fixed points oceanographical observations are usually made
from surface to a depth of about 1200 m. about 12-24 times a month,
the main oceanographical elements observed being water temperature,
chlorinity, and contents of oxygen and plankton. In the present paper
the authors intend to report some results of investigation on the varia-
tions of water temperature and chlerinity in deep layers mainly, together
with some other results, made from the data of observation at the fixed
POE ENT. (hic-ali):
2. WATER J EMPERATURE
(a) The annual variation of water temperature. In the first place,
the authors calculated the monthly mean water temperature of each
layer. Figure 2 shows the variations thus obtained of water tempera-
ture of the layers 0 m. (surface), 25 m., 50 m., 100 m., 200 m., 300 m.,
400 m., 500 m., 800 m., 1000 m. and 1500 m. From this figure we can
see that the water temperature near the surface becomes minimum in
February or March and maximum in August or September and that,
788 EIGHTH PACIFIC SCIENCE CONGRESS
for the layers from 100 m. to 300 m. deep, the phases of change of water
temperature are nearly coincident and the maximum temperatures
generally appear between October and December. Moreover, the time
of occurrence of the maximum temperature of each layer near the sur-
face (0 m.—100 m. deep) tends to lag with increasing depth. For
example, the maximum temperature of the surface layer appears in
August, while that of the layer of 50 m. depth appears in October or
November. This time-lag may be regarded as mainly due to the effect
of eddy conductivity of sea water. If we assume that the said variation
of water temperature near the surface is due to the effect of eddy con-
duction alone, the amplitude A, of the annual variation of water tem-
perature of a layer of depth z is expressed by the formula
AA coe e—a\t (1)
PT
where A, is the value of A, for z == 0 (surface), » the coefficient of eddy
conductivity, and ; the period of variation (assumed sinusoidal), of the
water temperature. Again, let ¢ be the phase lag of the variation of
water temperature at the depth z; then
ene] |S ae ae
If we calculate the value of » by the formulae (1) and (2), using the
data of oceanographical observations in 1948, we have the results as
follows:
Layer By formula (1) By formula (2)
0 m—50 m. 7.55 2.39
0 m.—100 m. eral 417
These values of », are not so extravagant in the order of magnitude.
However, as seen from the above results, the values of » calculated by
the two formulae (1) and (2) do not agree very well with each other.
This is because we have neglected the effect of heat transfer other than
that of eddy conduction.
(b) Long periodic change of water temperature. As seen from
Figure 2, in the variation of water temperature of each layer, longer
and shorter periodic changes other than the annual variation are also
recognized. In order to eliminate the annual variation, if we apply
the method of twelve-month moving average to these data, we have
the results as shown in Figure 3.
From this figure we can see that the water temperature was rising
from 1948 to 1951 and has been falling since the summer of 1951. As
for the cause of this periodic variation, we cannot give any definite
explanation for the present, but it seems that this variation is due to
a long period change of water mass situation.
OCEANOGRAPHICAL CONDITIONS OF THE SEA IN THE PACIFIC OCEAN 789
(c) Short periodic change. On the other hand, as mentioned above,
in the variation of the water temperature of each layer, a short periodic
variation is also recognized. ‘This is especially the case for the layers
50 m., 100 m., 200 m. and 300 m. deep.
Now, the maxima and minima of temperature of the 100 m. layer
as shown in Figure 2 were read off, and the time intervals between two
maxima or minima were measured and are shown in the following table.
__ { Period (in Months) 3 4 5
Time Interval of Temperature Maxima <
| Frequency By tl
Peri i [ 7
Time Interval of Temperature Minima Soe! Woon MMOS) Be
Frequency Hea Boe
(From 100 m. layer)
As is seen in this table, the short periodic change in question has a
predominant period of 3 months. J. Fukuoka, one of the present
authors, and T. Yusa have studied the variation of water temperature
along the so-called “C-line” (Fig. 1) and it has been known that there
exists a change of water temperature of about 3-month period in the
sea adjacent to the Tohoku District (Northeastern Japan).
3. CHLORINITY
Figure 4 shows the variations of chlorinity at different depths. From
this figure we can see that the annual variation of chlorinity in the
upper layers has a maximum in spring, which is due to the effect of
continued evaporation, and a minimum in autumn, which is caused
by heavy precipitation. Again, we can recognize that the chlorinity
in the layers 50-100 m. deep, tends to become high from early summer
to autumn. ‘This could be due to the effect of the Kuroshio having
high chlorinity. On the other hand, the chlorinity in the layers 200-
500 m. deep is generally lower, which could be due to the effect of the
Oyashio creeping current.
Further, if we look at the variation in chlorinity shown in Figure 4,
we can recognize that the long periodic change of chlorinity is similar
to that of water temperature, which is a fact worthy of being noted.
Thus it seems that the long periodic change of chlorinity is also due
to a long period change of water mass situation.
4. COLOUR OF THE SEA, TRANSPARENCY AND PLANKTON VOLUME
At the point “Exira,’ the observations of colour of the sea and
transparency have been performed since March 1948, and the collec-
tion of plankton since March 1950. In the following, we shall outline
the result.
790 EIGHTH PACIFIC SCIENCE CONGRESS
The annual variation of the colour of the sea is similar to that of
the transparency, both with two maxima, one in summer and the other
in winter, and two minima, occurrmg in spring and autumn. As to
the seasonal variation of plankton volume, a very distinct maximum,
a phenomenon of the so-called burst growth, occurs in spring and a
less marked maximum in autumn, and a marked minimum appears in
winter, and also, in a less degree, in early autumn. An experimental for-
mula D == 21.8)-%25, where D represents transparency expressed in
meters, and V the plankton volume in cc/m.*, has been determined
(Fig. 5), although there are involved somewhat unsatisfactory conditions
such as the disregard of composition of plankton, the inequality between
the values of transparency and the depth of the net haul, ete.
REFERENCES
(1) J. FUKUOKA and T. Yuss: The Variation of the Oceanic Condition in the
Sea Adjacent to Tohoku District. Oceanogr. Mag., Vol. 4, No. 2, 1952.
(2) T. NAN’NITI: On the Fluctuation of the Kurosiwo and the Oyasiwo.
Papers in Meteor. and Gecphys. (Meteorological Research Institute,
Tokyo), Vol. 2, No. 1, 1951.
(3) J. FukuoKA and T. Tsurki: On the Variation of the Oceanographic Con-
dition of the Sea near the Fixed Point “Hxtra.” Records of Oceanogr.
Works in Japan. (Japanese National Commission for Unesco) Vol. 1,
No. 1 (New Series), 1953.
(4) M. KorzumMi: On the Annual Variation in Oceanographical Elements at a
Fixed Point (39°N, 153°E) in the Pacific Ocean. Records of Oceanogr.
Works in Japan. (Japanese National Commission for Unesco) Vol. 1,
No. 1 (New Series), 1953.
CCEANOGRAPHICAL CONDITIONS OF THE SEA IN THE PACIFIC OCEAN 791
Fic.
FIG.
FIG.
IDES
FIG.
MG O SE RNAIOIN'S
1.—Map showing ‘‘C-line” and the fixed points “Extra” and “Tango.”
2.—Variation in water temperature at different depths.
3.—The variation of the water temperature obtained by taking twelve-
month moving average.
4.—Variaticn in chlorinity at different depths.
5.—Relation between transparency and plankton volume. The curve
represents D-21.8V—).25,
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OCEANOGRAPHICAL CONDITIONS OF THE SEA IN PACIFIC OCEAN 793
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EIGHTH PACIFIC SCIENCE CONGRESS
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11
OCEANOGRAPHICAL CONDITIONS OF THE SEA IN PACIFIC OCEAN 795
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796 EIGHTH PACIFIC SCIENCE CONGRESS
O {-0 2-0 3-0 4-0 5-0 “rn V
FIGURE 5
DISTRIBUTION OF COPPER AND ZINC IN SEA WATER (1)
By YosHim1 Morita
Chemical Institute, Faculty of Science
Nagoya University, Japan
The contents of copper and zinc in the sea water have been repeat-
edly determined by many investigators. However, many of the data
so far obtained are unfortunately unreliable, owing partly to defects
in the methods and their application and partly to contamination from
the metallic sampler used and often from insufficient care in handling
collected samples.
Previously the author developed a procedure in which such defects
and contamination can be avoided. He examined 21 samples of the
surface waters from Tokyo Bay and Ise Bay (1).
Although these waters looked to be contaminated more or less by
land drainage, their contents in copper and zinc were found far smaller
than the values ever reported. Also it was noticed that their values
decreased from the head of the bay towards its mouth, seemingly in
parallel with contamination.
Naturally we are forced to expect that the far distant waters, free
from the effect of land, will give smallest values and the copper value
will drop probably below 1 yg/I.
Thus the study was extended along this line. First, the surface
waters of the “Kuroshio” area were examined in May, 1951 on board
No. 5 Kaiyo-maru, a surveying boat of the Hydrographic Office, Mari-
time Safety Agency, while at the second time the vertical distribution
was determined in Sagami Bay and Suruga Bay in February, 1953, on
board Umitaka-maru of the Tokyo University of Fisheries.
For collecting surface water a glass sampler was used, which had
previously been thoroughly cleaned with special care; while for deep
water sampling an Eckmann type sampler, coated with acrylic resin,
was devised, taking into consideration that the trials by previous inves-
tigators, who used a metallic sampler, failed in getting a satisfactory
result, due to probable contamination from the instrument. The deter-
mination was carried out by mixed-colour colorimetric titration with
dithizone (2).
797
798 EIGHTH PACIFIC SCIENCE CONGRESS
The results, given in Tables I and II, show that
1) The surface waters from Sagami Bay and Suruga Bay are richer
in copper and zinc in comparison with those from the “Kuroshio” area,
a fact indicating that the former are still affected by land drainage to
any measurable extent.
2) The vertical distribution, given in Table II, shows that this
contamination is limited to the surface and that the contents of the
elements decrease in layers below.
3) Their contents, once decreased, rise up again from 200 m. or
thereabout downwards. At the present stage of study it is difficult to
decide what is the main factor determining the rise-up observed. How-
ever, at least it may be said that here setting free of these elements
from dead organisms by decomposition in the course of falling down,
contributes to the enrichment in the deeper waters, which is usually
the case with other nutrient salts such as phosphate.
Unfortunately in the February cruise in 1953, the sampling from
the “Kuroshio” area could not be done because of unfavourable condi-
tions of the sea. The author is now planning, for the next step of
study, an examination of samples from such an area as well as from
other bays. Also the study will be extended to far deeper layers than
ever examined and further to the seasonal variation of the elements.
Efforts are also being made to improve the sampler by which the dura-
bility of acrylic resin coating is expected to increase.
Deepest thanks are due to Professor K. Sugawara for his guidance
and to Dr. K. Suda, Director of Hydrographic Office, Maritime Safety
Agency, and Professor M. Uda, the Tokyo University of Fisheries, by
whose courtesy the author took advantage of participating in the sur-
veying cruises. Also a sincerest condolence must be expressed to the
late experts and crewmen of No. 5 Kaiyo-maru who missed, with the
ship, the voyage for the exploration of Myojin Reef, which appeared
last September because of undersea eruption, in recollecting the warmest
help offered by them during my stay on board.
TABLE I
CorpPpeR AND ZINC IN THE SURFACE WATERS FROM THE ““KUROSHIO” AREA
LOocATION DATE Cu peg/) Zn ug/l
Sis Bh BYP OG? ING, IBIS ORY 1a May 1, 1951 0.5 1.5
Sin Gh ene CO aie aise all! 33) May 2, 1951 0.6 1.8
St. 4, 38° 16.5’ N, 138° 13.5’ E May 2, 1951 0.7 —_
DISTRIBUTION OF COPPER AND ZINC IN SEA WATER
TABLE II
VERTICAL DISTRIBUTION OF COPPER AND ZINC
799
SAGAMI BAY
SURUGA BAY
(1) Y. Morita, J. Chem. Soc. Japan 71, 246 (1950).
(2) Y. Morita, J. Chem. Soc. Japan 69, 174 (1948).
Location: 35° 03.8’ N, 139° 21.8’ E Location: 35° 00’ N, 188° 39.1’ E
Date: Feb. 12, 1953 Date: Feb. 15, 1953
DEPTH Cu Zn DEPTH Cu Zn
m ug/l ug/l ™m ug/l ug/l]
0 0.9 ee 0 0.8 2.3
50 0.6 1.8 50 — —
80 0.8 2.0 80 -= —
100 — — 100 0.6 1.8
200 0.8 2.4 200 0.6 1.9
400 0.9 2.8 400 0.5 4.4
600 0.9 3.0 600 1.0 eaae
1,000 15) 4.2 1,000 —- —
REFERENCES
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL
CURRENT
By ERWIN SCHWEIGGER
Compania Administradora del Guano
Lima, Peru
The fact that the Peruvian Coast has a temperate and dry climate,
although geographically situated in tropical latitude, is known since
the Spanish conquest of Peru and northern Chile. The phenomenon
of rainless years, especially rainless summers is due to the effects of the
cool Peruvian Current which flows slowly along the greater part of the
Chilean and almost the whole length of the Peruvian coasts, in the
direction to the Equator. It was first explained by Alexander von
Humboldt, who believed that this current was derived from the cold
polar waters in the Antarctic. Modern investigation, however, proved
that the low surface temperatures along that part of the West coast of
South America are produced by “upwelling” of water from depths at
more or less 130 m. below the surface. (Schott, 1931; Gunther, 1936).
In this zone, as in any other place, the most interesting phenomena
are brought forth by anomalies which in the Peruvian Current are also
observed from time to time. The basis of our knowledge regarding
these abnormalities is laid by the description of the occurrences in 1891
and 1925, made by Schott in 1931. They have their origin in changes
of the course of the Equatorial Countercurrent in combination with
the displacement of the zone of convergence of the trade-winds of the
northern and the southern hemisphere, and of the situation of the baro-
metric low-pressure-area. Although very little is known regarding the
mechanism which originates these changes, we are well informed of the
effects it has on the Peruvian Coast. Thunderstorms and heavy rain-
falls accompany the change of the hydrographic conditions as far as
about 9°S. Further south the coastal plain and the western slopes
of the Andes are soaked by rains producing great landslides and destruc-
tion of arable soil. Together with such meteorological and hydro-
graphic anomalies goes a deep change in the ecologic conditions in the
Peruvian Current which leads eventually to a complete destruction of
the habitual life in the current.
The last of these great catastrophes occurred in 1925, and since
then the system of the current and life depending upon its normal con-
801
802 EIGHTH PACIFIC SCIENCE CONGRESS
ditions were repeatedly subject to invasions of the Equatorial Counter-
current with some of its consequences but never in such a degree as
reported for the summer of 1925. The author presented to the Sixth
Pacific Science Congress in 1939 a paper regarding the hydrographic
anomalies observed in that same year and by coincidence he wishes to
relate to the same Congress to be held in November 1953 about other,
and perhaps even greater, disturbances of the normal conditions in the
summer of 1953.
It must be said that nearly all reports contained in the oceano-
graphic literature about destructive biological changes in the Peruvian
Current are extremely exaggerated and generalize the extraordinary
events which have been observed only twice during the last 62 years.
Some abnormal situations, marked by the emigration of the guano-birds,
are recorded for November-December 1912, March 1917, March and
June 1923, but only for 1923 is the death in greater extension of fishes
mentioned (Lavalle 1917, 1924). Later perturbances occurred in 1932,
1939, 1941, 1951 and the last one just recently in 1953, this, however,
without any biological consequences. ‘These are characterized by the
emigration of almost all or at least an appreciable part of the guano-
birds which occupy the small islands off the Peruvian shores. Nothing
has been heard or seen since 1938 of a widespread mortality of fish,
except some rare occurrences when fishes still alive were washed ashore
(1941), perhaps poisoned or suffocated by lack of oxygen. However,
oceanographic perturbances have taken place in all these years and in
a lesser degree also in 1949. If it were not for the behavior of the
guano-birds, which are carefully watched in view of their importance
as producers of guano, one source of Peru's great wealth, the abnormal
conditions in the sea would not be noticed. Abnormalities can only
be detected by careful hydrographic observations.
It is not the intention of this paper to enter into details about the
biological changes which take place in years of greater hydrographic
perturbances, but only to show the abnormal features of the summer
of 1953 in comparison with those of some other years, and to discuss
some hydrographic phenomena connected with these disturbances.
All the data used for the original charts reproduced herewith are
based in their greater part on observations made by the author on board
ships of the Guano-Company (Compania Administradora del Guano,
Lima), in sailing ships in 1939 and 1941 and complemented by data
obtained from merchant vessels navigating along the Peruvian Coast.
The data collected are kept in special oceanographic archives of that
same Company. It must be stated here that the great merit of the
Guano Company, besides the absolute and well planned protection
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 803
given to the guano-birds, consists since the first years of its existence
in having initiated and supported scientific investigations related not
only to the birds, but also to the whole ecological and hydrological
complex in which they live and upon which depends their well-being.
Selected from the representation of abnormal situations are the
years 1939, 1941 and 1953. Maps concerning the year 1947 which might
be looked at as an abnormal year have been inserted. It has been in-
cluded only because it shows for the month of March an ample review
of the conditions in the outer limits of the Gulf of Guayaquil. All
available data have been sampled and averaged in squares of half a
degree of geographical latitude and half a degree of geographical longi-
tude, and according to the averages thus obtained isotherms were
traced. For all the above mentioned years drafted charts are presented
for the months of March and April, although in some cases maps refer-
ring to February would already show some major anomalies; these, how-
ever, have been left out, in order to avoid undue length of this paper.
The number of observations on which these maps are based is as
follows:
19395) March 131) April 157
1941 4% 619 ‘3 293
1947 ‘ 855 i 681
1953 cf 380 rs 780
An isothermic chart for normal conditions in the Peruvian Coastal
Current (Fig. 1) shows the isotherms running parallel with the conti-
nental coast, whilst abnormal situations originated by an invasion of
the Equatorial Countercurrent in 1891 and 1925 are represented by the
almost perpendicular course of the isotherms to the shoreline (Figs. 2
and 3). On the other hand, both of these maps show along the whole
Peruvian littoral as far south as Callao (Fig. 2) or a little further than
10° S, temperatures of 26°C, although perhaps in the immediate vici-
nity of the coast, lower temperatures may have been present.
None of our charts (Figs. 4-7) shows something similar, running
all the isotherms more or less parallel to the coast. The highest inshore
temperatures have been observed in 1941, but the highest temperatures
in the outer part of the Gulf of Guayaquil and also off the southern-
most part of Peru were observed in 1953. March 1939 (Fig. 4) shows
the nearest approach of a 27° isotherm to the Peruvian coast at 8°S
and that of the 26° isotherm at 10°S. The extension of the hydro-
graphic perturbance brought forth by the warm waters which evidently
came from the north is easily seen by comparing the maps for March
1939, 1941 and 1953 (Figs. 4, 5 and 7), with March 1947 (Fig. 6), where
S04 EIGHTH PACIFIC SCIENCE CONGRESS
the outer limits of the Gulf of Guayaquil are completely under the
influence of the very far northward reaching outlet of the Peruvian
Current, whilst only the inner parts of the Gulf indicate higher tem-
peratures belonging to waters which may be able at any moment to
form the “real Nifio Current” (Schweigger, 1945).
The maps for April (Figs. 8-11) contrast strongly with those for
March. It is evident, in all of them, the depression of the sea-surface-
temperatures as compared with March. Only in 1953 (Fig. 11) the 26°
isotherm was observed nearer to shore than in March of the same year.
The diminution of the surface temperatures is especially visible in the
southernmost part of the Peruvian littoral and also in the Gulf of Gua-
yaquil where all temperatures are reduced. Unfortunately, data are
missing for April 1941 north of 9°S and south of 14°30’S, and it is
just this year which seems to have shown the greatest anomaly of all
the years since 1925. The extended voyage of the author to the region
W of Pisco (12°-14°S) allowed him to trace the isotherms over a great
area in the open sea, and it must be deduced from the distribution of
the hourly observed surface-temperatures that in April 1941 the iso-
therms for 26°, 25° and 24°C had a course nearly perpendicular to
the continental coast, at least from a certain distance on, being space
left for lower temperatures along the Peruvian shore.
Three parts of the coast deserve our greatest interest: The Gulf
of Guayaquil, the area included by the latitudes 9° and 10°S and the
region between Atico-Ilo-Arica. The position of the isotherms in the
Gulf of Guayaquil for March and April 1953 (Figs. 7 & 11) leaves no
room to doubt that the high sea temperatures are derived from the
NW, which can only mean an advance of the Equatorial Countercur-
rent, corroborated also by low salinities. In March 1939, as in March
and April 1947 (Figs. 4, 6 and 10), the highest temperatures in this
zone belong without doubt to the interior parts of the Gulf and extend
from there to the W and SW. The conditions in April 1939 and in
March 1941 (Figs. 8 and 9) cannot be determined satisfactorily in view
that observations are available only for one route of navigation, al-
though in March 1941 the highest sea temperature (27.5°C) was observed
E of 81°W whilst in the half-degree-square just W of that meridian
the surface temperature was found half a degree lower (27.0°C). The
warm waters south of Cabo Blanco, and especially those southwest of
Aguja Point, must be brought in connection with the open ocean, but
not with certainty with the Equatorial Countercurrent, although in
March 1941 very low salinity was observed between 8° and 6°30/’S
which induced one to believe that these waters had come from the
Equatorial Countercurrent. But as these titrations of salinity had to
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 805
be made without control by standard-seawater, their true oceanographic
value cannot be emphasized.
The revision of the charts regarding the region between 3° and
4°S leads to distinguish two different movements of warm water north,
northwest and northeast of Cabo Blanco. Figures 4, 6, 10 and perhaps
also Figure 5 show the expansion of warm waters from the inner part
of the Gulf of Guayaquil. These surround frequently Cabo Blanco in
a southerly direction and are then identifiable as far as 5°S, sometimes
even further, to the south by higher temperatures, lower salinity and
a different fauna (especially fishes) (Schweigger, 1943, 1945), but are
without any climatic influence on the northern territories of Peru (Zo-
rell 1928). Such a southerly flow of warm water is not only produced
in summer months, it may happen in any month of the year.
Contrasting with these features are the maps for 1953 (Figs. 7 and
11) in which the warm water without any doubt is coming from the
northwest. Such a direction of the flow is also indicated in Figure 2
(1891) and this is evidently also the meaning of the charts in Figure
3 (1925). Such a situation seems to be characteristic for the major
disturbances in the outer parts of the Gulf of Guayaquil with the conse-
quent production of climatic abnormalities at least in the northern
parts of Peru.
A rapid fall of surface temperatures near Cabo Blanco and south
of it indicates the presence of warm water derived from the interior of
the Gulf of Guayaquil, whilst on the other side high inshore tempera-
tures between Cabo Blanco and Aguja Point are connected with the
inrush of warm water from the northwest, which comes from the open
South Pacific Ocean or the Equatorial Countercurrent. Following this
differentiation, it seems possible to attribute the high temperatures
between 4° and 6°S shown for March 1941 (Fig. 5) to the influence
from northwestern areas.
The second interesting feature in these maps is the pressure of
warm water against the coastline between 9° and 10° and sometimes
11°S. This is most impressively represented in April 1953 (Fig. 11)
but can be deduced to a greater or lesser extent from many of our maps
and even so from Figure 3. An elevation of the surface temperatures
at the south or the southwest of Chimbote is observed almost regularly
throughout the year. The zone of warm water seems to be connected
with a countercurrent which spreads out south and southeastward in
coastal areas and is known by all navigators by its accelerating effect
when sailing from Huarmey on a southerly course. Repeated observa-
tions have shown that the water entering there is of higher salinity
than the normal inshore water, so that it seems justified to consider
£06 EIGHTH PACIFIC SCIENCE CONGRESS
the space S and SW of Chimbote, or W of Huarmey as one of the most
susceptible zones for the entrance of warm oceanic waters with the
tendency to spread out, not only in the direction of the flow of the
Peruvian Current, but also in the opposite direction (sometimes with
a wide-reaching influence on fisheries).
The presence of warm water in this part near the coast is also shown
in the isophletic diagram published by Schott (1931) for the abnormal
period of March 1925. The diagram reveals that the ships passing
between 8° and 10°S registered in almost all voyages higher tempera-
tures than those observed further north. This held true in April 1953
(Fig. 11) when temperatures of 26.5°C west of Chimbote were higher
than the temperature found about 3 days later off Cabo Blanco. The
possible heating influence of this zone upon the southward warm water
flow, recorded in 1925, has been mentioned by the author in an earlier
paper (Schweigger, 1949).
According to his own repeated experiences and the frequent obser-
vations made by merchant ships in all months of the year in this zone,
the author came to the conclusion that the advance of the warm waters
must be directed to the northeast as it is also suggested by Figures 4,
6 and 11. But nearly every one of our maps referring to summer months
shows at the NW or at the west of Chimbote the curvature of the iso-
therms, especially of those for 27° and 26° and 25° with its axis directed
to the SE, as if the warm water were rushing in from NW (see also
Fig. 3 for comparison). ‘This, however, is a problem whose discussion
may be taken up later.
Perhaps more interesting still is the region in the extreme south
of the Peruvian littoral which could be circumscribed as situated between
Atico-Ilo-Arica and Iquique (see Fig. 12). The center of this zone seems
to be the area off Ilo, from where the warm water makes its appearance
and then disperses partly in direction N and NW (together with the
Current) and partly to the southeast, turning outside Arica southward
and making itself discernible as far as the latitude of Iquique in the
form of a “tongue” of warm water keeping always at a certain distance
off shore.
The author has been able to corroborate such a distribution of
surface-temperatures in different opportunities travelling between Iqui-
que and Peruvian ports mostly during winter months, when tempera-
tures in this “tongue” were not so high to make it difficult to correlate
them with other temperatures in more northerly zones of the Peruvian
coast. But although this paper is really not so much concerned with
the southerly flow of warm water in northern Chile, it may not be
superfluous to illustrate such a situation by means of Figure 12, which at
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 807
the same time serves to underline the difficulty to understand the move-
ments which bring these high temperatures to the zone between Ho
and Arica.
Figure 12 differs from the other charts in so far as it combines the
observations of only two ships which sailed the whole Peruvian and
part of the Chilean coast from Talara to Iquique during 20 days (16th
of February to 8th of March 1948). The map contains also some earlier
observations made by the northbound vessel off Cabo Blanco and in
the interior of the Gulf of Guayaquil (8/9 of February) in order to
represent a typical distribution of high sea temperatures in the zone of
Cabo Blanco and northeast of it. Both these ships passed, according
to a previous understanding, a zone situated 80-90 miles W of Pisco
in order to obtain information about the conditions there at this time
of the year. The comparison between the observations registered W
of the northern part of the Peruvian shore (4°-6°S) and those made
while sailing from Talara to Callao, suggests that a very strong inva-
sion of warm water must have taken place in the 8 days between 9th
and 17th of February which shoved the 24° isotherm more or less 90
miles to the SE. The most interesting feature of Figure 12 is the appear-
ance of the temperature of 26.2°C off Arica (27th of February) whilst
neither the first boat passing the zone W of Pisco (16th of February)
nor the second one (7th of March) observed more than 25.3°C. Between
these dates the warm water off Pisco had expanded, but it cannot be
said if its extension found on the 7th of March was already diminished
after having reached a culmination in the foregone days or if the ex-
pansion was a steady one during all the time. The high temperatures
off Arica place before us the following problem: If they are connected
and how far with the invasion of warm water in 6°-7°S, or the other
one in 13°-14°S. That the temperature registered off Arica was a
recent one, can be concluded from the fact that data obtained in the
same half-degree-squares before and after the sailing from Iquique prove
that the water was cooler between the 22nd and 24th than between the
26th and 27th of February.
It seems undeniable that such a “tongue” of warm water as showr:
in Figure 12 and which is also confirmed by a series of maps in a recent
paper by Bini (1952) must have its origin in the region situated between
Ilo and Arica. It seems difficult, however, to trace back the warm
water and connect it with waters still warmer in further northern parts
of the Ocean. It seems possible to draw the isotherms for 25°C in 17°
and 18°S (Figs. 4, 7 and 12) in such a manner that they join the iso-
therms for the same temperatures at the N or NW of Callao. The
author does not feel that such a course might be considered correct.
808 EIGHTH PACIFIC SCIENCE CONGRESS
April 1941 (Fig. 9) shows for example that the isotherms for 26°,
25° and 24° at the peak of the invasion of the warm waters must have
had a direction from approximately WSW-ENE. It seems improbable
that they turn further offshore to the direction NW-ES in order to
show up again off Ilo and Arica. Should we believe that the high
temperatures reach this region as consequence of the invasion of warm
waters from the NW and are curtailed when the invasion reaches the
culminating point (isotherms stressed out WSW-ENE), or is there a
steady flux of new warm water from another source? We must also take
in account that the elevation of temperature off Mollendo-Arica is
practically a constant phenomenon, although the amplitude of the varia-
tion of temperature is less in winter time.
On the other hand, according to the map published by Schott and
Schu, (quoted from Gunther, 1936), surface temperatures of 22°-20°
are traced as belonging to the latitudes 17°-20°S in the open ocean
far away from the Continental Coast, deflected, however, some 1200
miles offshore in the NE direction, by the northerly movement of the
waters along the coast of South America. Their position during March
1891 and 1925, makes us look with awe at the overwhelming forces of
the Equatorial Countercurrent, which stemmed back these isotherms to
their position in the outer ocean over an area of nearly 1200 miles wide
in those latitudes. We see now that none of the perturbances of 1939,
1941 and 1953 can be compared with the catastrophes of 1891 and 1925,
which for their part restituted for a short time the hydrographical and
meteorological situation corresponding to the geographical latitudes of
the coast involved, where the cool water of the Peruvian Current has
created a thermic anomaly of such a magnitude.
None of our maps entitles us to draw the isotherms in the zone off
Ilo-Arica-Iquique in the same manner as for 1891 and 1925. The iso-
therm for 25° situated there has therefore been left open without sug-
gesting any solution of our problem.
Nevertheless, it might be possible to look for an explanation of
this phenomenon off Ilo and Arica, and the other one, created by the
warm water off Chimbote, in the hypothesis of Gunther (1936). He
supposes the existence of two different countercurrents, “warm wedges’,
off the Peruvian Coast which flow in a southeasterly direction, one start-
ing more or less off Aguja Point and reaching as far as the latitude of
Callao and the other one coming out of a region WSW of Pisco and
entering near the coast just off the bay of Arica. Both these counter-
currents transport, according to the view of Gunther, warm water from
the NW to the SE. The author of this paper has objected (1943)
against the existence of these two “warm wedges’, because Gunther cor-
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 809
relates observations which are too far apart, not only in space but also
in time by many days and even by weeks. This is a procedure which
does not seem advisable in a current system exposed to so many and so
sudden changes, as Gunther himself had to admit. During all his nu-
merous voyages in the Peruvian Current, the author only once came
across a situation which could induce him to accept the idea of
Gunther (1943, p. 242).
On the other hand the fact must not be overlooked that Gunther
made his investigations in the Peruvian Current in the winter of 1931
between the warm summer of that same year and the still warmer one
of the year 1932, so that the countercurrents appeared to be the result
of some unstable situation in the Current, an idea which might be sup-
ported by our maps which show that in all of the abnormal years the
warm temperatures advanced more or less in the same sense as proposed
by Gunther (the line of the least resistance?). The northerly axis of
these “warm wedges” runs parallel with the axis of the bend of the iso-
therms for the high temperatures which according to our maps seem
to advance in direction to Chimbote, Huarmey or even Callao; there
is only a slight difference insofar as the main axis of Gunthers counter-
current lies a bit further to the south and west than ours. It should,
however, be taken into account that Gunther’s observations have been
made during winter months, whilst our figures are all referring to sum-
mer time.
The southerly countercurrent constructed by Gunther does not co-
incide, as well as the northerly one does, with the apparent movements
of warm water to the SE; but it would be possible to accept this theory
of Gunther’s as a working hypothesis. The author must repeat that
the Peruvian reconnaissance could not yet be widened so far out at sea
as to prove or deny for any time of the year the existence of such
countercurrents, and it must be borne in mind that the Guano Company
has to make great sacrifices for all the research work done. ‘The voyages
made by the author took place during the routine travelling of the ships
of the Guano Company, which allowed their captains, with a fine under-
standing of the scientific requirements, to take different courses from
the normal ones, according to the wishes of the author in order to
make hydrographic investigations, mostly in correlation with the more
important biological factors.
But even if we accept the warm wedges of Gunther, the problem
is not yet resolved because the same Gunther has not been able to
answer exactly the questions as to where these countercurrents are
coming from. As his view of the conditions was limited to the winter
months, it seems possible that for the summer time the origin of these
&10 EIGHTH PACIFIC SCIENCE CONGRESS
countercurrents may lay further off shore and to the north, as he indi-
cates, so that at least the northerly one might perhaps be brought in
contact under still unknown conditions with the Equatorial Counter-
current. But as for the southerly one, there seems to be no other ex-
planations as a bending of the isotherms in the open ocean from their
run SW-NE to the course NW-SE. ‘These problems must be left open
to further investigations.
PUBLICATIONS CITED
Bint, G. 1952. Osservazioni sulla fauna marina delle coste del Chile e del
Peru con speciale riguarde alle specie ittiche in generale ed al Tonni in
particolare. Bol. di Pesca, Piscicoltura e Idrobiologia. Ato XXVIII,
Vol. VII (n-s.), pp. 3-52.
GUNTHER, E. R. 1936. A Report on Oceanographical Investigations in the
Peru Coastal Current. Discovery Reports, Vol. XIII, pp. 107-276
DE LAVALLE, J. A. 1917. Informe preliminar sobre la causa de la mortali-
dad de aves ocurrida en el mes de marzo del presente ano. Mem. Comp.
Adm. Guano, VIII, pp. 61-84.
1924. Estudio de la emigracién de las aves guaneras ocurrida
en los meses de mayo y junio del ano 1923. Mem. Com. Adm. Guano,
XV, pp. 94-107.
SCHWEIGGER, E. 1939. Studies of the Peru Coastal Current with reference
to the extraordinary summer of 1939. Proc. 6th Pac. Scie. Cong. III,
pp. 177-195.
1943. Pesqueria y Oceanografia del Pert. Lima.
———-—— 1945. La “Legitima Corriente del Nino”. Bol. Com. Adm. Guano,
Vol. XXI, pp. 225-296.
1949. Der Perustrom nach zwoelfjaehrigen Beobachtungen.
Erdkunde, Bd. III, pp. 121-132, 229-241.
ScHoTT, G. 1931. Der Peru Strom ... Ann. Hydr., pp. 161-169, 200-
213, 240-252.
ZORELL, F. 1928. Der “El Nino-Strom” im Jahre 1925. Ann. Hydr., LVI,
pp. 166-175.
—-—_
ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 811
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ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 813
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ABNORMAL SUMMERS IN THE PERUVIAN COASTAL CURRENT 815
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QUANTITATIVE DETERMINATION OF TUNGSTEN AND
MOLYBDENUM IN SEA WATER
By MasayosuH1 IsHiBaAsHI, TSUNEBOBU SHIGEMATSU
and YASUHARU NAKAGAWA
Kyoto University, Japan
As an amount of molybdenum in sea water, the values obtained
by Ernst et al.(1), Bardet et al.(2) and Ishibashi et al. (3) are about
0.3, 3 and 10 pg per kg. of sea water respectively.
Tungsten has been detected in sea water, but the amount of it is
not yet quantified. From the regularities of the amount of elements
dissolving in sea water (4), Ishibashi and Shigematsu calculated and pre-
sumed the amounts of molybdenum and tungsten dissolved in sea water
as about 10 »g Mo/1. and 0.4 pg W/1.
We determined the amounts of molybdenum and tungsten in sea
water and found that the amount of molybdenum was almost same as
that previously obtained by our thiocyanate method (3), and the amount
-of tungsten was about 0.1 »g per |. of sea water.
]. COLORIMETRIC DETERMINATION OF [TUNGSTEN AND MOLYBDENUM
We studied on the colorimetric procedure for trace amounts of
tungsten and molybdenum by dithiol (toluene-3,4-dithiol) and estab-
lished the conditions necessary and satisfactory to obtain accurate results.
Reagents:
Dithiol solution; dissolved 0.2 g. of dithiol in 100 ml. of N-NaOH,
freshly prepared, or stored under H, atmosphere. ‘The solution is stable
for 2 months under H,.
Standard tungstate solution; 10 »g W/ml. and 10.0 pg W/ml.
Standard molybdate solution; 10 »g Mo/m1l. and 10.0 »g Mo/ml.
Procedure:
The solution containing molybdenum and tungsten was diluted to
50.0 ml. The 25.0 ml. aliquot of the solution was acidified with 2 ml.
cf N-HCI, then 1 ml. of dithiol solution was added to it, and heated
on boiling water for about 10 minutes. After cooling, the resultant
dithiol complexes were extracted with 10 ml. of butylacetate. The color
intensity of butylacetate solution (Extinction E,) was measured by using
Pulfrich Photometer, the cell length 2 cm., the filter S661. To the
817
818 EIGHTH PACIFIC SCIENCE CONGRESS
other 25 ml. aliquot, 1 ml. of 10% citric acid solution and 2 ml. of
N-HCI were added, then 1 ml. of dithiol solution and heated on boiling
water for 10 minutes. And the molybdenum complex was extracted
with 10 ml. of butylacetate. The color intensity (Extinction E,) was
measured as above.
The amounts of tungsten and molybdenum were calculated from
the following equations:
pe W =.58.8 x (E, — E,)
pg Mo = 83.0 X (E, — 0.040)
It was found that through this procedure 1-40, of molybdenum
and tungsten can be determined within £0.5y ‘of error, and this meas-
urements are only interfered by the presence of iron and copper.
2. CONCENTRATION OF MOLYBDENUM AND TUNGSTEN IN SEA WATER
For the purpose of separating and concentrating the molybdenum
and tungsten in sea water, we utilize the coprecipitation method as
follows:
To 0.5-15 1. of artificial sea water (5), 1-3 ml. of HNO, and 200 mg.
of ferric iron as ferric nitrate solution were added. Then 50-100 ml.
of 1M hexamethylenetetramine solution was added, and allowed to
stand overnight to settle the precipitate. The precipitate was filtered,
dried and ashed in platinum crucible at low temperature lower than
500°C. ‘The residue was fused with small amounts of the fusing mix-
ture (Na,CO, + K.CO, 1:1). The fused mass was_taken up with
10-20 ml. of hot water, and filtered. The filtrate was just neutralized
with 4N-H,SO, to litmus.*
The results obtained are shown in Table I, nos. 1-9.
Determination of tungsten in the presence of large amounts of
molybdenum: In the presence of large amounts of molybdenum
(>10 x W), tungsten was determined inaccurately by the above proce-
dure. In sea water, the amount of molybdenum may be about 30 times
larger than that of tungsten (4), so molybdenum was separated as sul-
fide from tungsten as follows: To the neutral solution *, 1 ml. of 50%
citric acid solution and 5 drops of 4N-H.SO, were added, and H,S bub-
bled vigorously for a few minutes. The sulfide was filtered through a
small filter, and washed with H,S water. The filtrate was evaporated
to a few ml., filtered again through the filter, if necessary, and washed
with hot water; and the solution was dried up in a platinum crucible.
The residue was ashed with a small amount of sodium carbonate and
fused. ‘The mass was taken up in hot water and just neutralized with
H.SO,. ‘The solution was diluted to 50.0 ml., and the amount of tungs-
ten and residual molybdenum was determined as above.
* Residual molybdenum.
DETERMINATION OF TUNGSTEN AND MOLYBDENUM IN SEA WATER 819
The results obtained are shown in Table I, Nos. 10--16
TABLE I
RECOVERY OF Mo AND W
No | “W Appr (ue) Mo ApbpED (pe) W Founp (ug) | Mo Founp (ug)
1 0.0 | 0.0 0.0 0.0
2 30.0 | 0.0 29.1 | 0.0
3 0.0 30.0 0.0 99.3
4 5.0 10.0 4.9 9.3
Sita 10.0 | 10.0 | 8.9 | 2.0
Gal 10.0 | 20.0 12.5 18.3
vi 10.0 30.0 Bol 28.0
Ss 20.0 20.0 18.5 18.3
Diep 30.0 30.0 28.0 26.9
NOat aa 0.0 1000 | <0.2 13.2 *
11 20.0 | 1000 18.0 7.1 *
12 30.0 1000 30.6 3.5 *
13 30.0 1000 O71 10.6 *
14 30.0 1000 28 | 6.8 *
15 30.0 1000 26.8 10.8 *
16 30.0 1000 26.4 | 10.6 *
* Residual molybdenum.
The recoveries of molybdenum and tungsten in this procedure are
both about 90%.
3. DETERMINATION OF MOLYBDENUM AND TUNGSTEN IN SEA WATER
About 50 1. of the sample water was taken, and acidified with 6 ml.
of nitric acid; 400 mg. of ferric iron was added as ferric nitrate and
thoroughly mixed. To the solution, 200 ml. of hexamine nitrate was
added and thoroughly mixed. To the solution, 200 ml. of hexamine
solution (containing 100 gr. of hexamine) was treated as above men-
tioned, and the amounts of tungsten and residual molybdenum were
determined.
Molybdenum sulfide in the filter was ashed at low temperature and
dissolved in sodium hydroxide. Then the amount of molybdenum was
colorimetrically determined by the dithiol method.
The results obtained are shown in Table II.
TABLE II
tee | Mo Founpb
SEA WATER TAKEN | W FOUND
| Residual | Sulfide Sum
ug | ug | ug ug
40 1. | sro ts Nl tG 340 351.6
60 1. ee 90. MRE ISS) lol. 3598 651.6
| |
4014+ 5.0u¢ W | 8.97
$20 EIGHTH PACIFIC SCIENCE CONGRESS
The sea water was sampled on June 13th, 1952, offshore at Shira-
hama, Wakayama prefecture, Japan.
As seen from Table II, the molybdenum content of the sampled
tungsten content is 0.10, 0.15 and 0.11 »g/1., in the average 0.12 pg/1.
We wish to thank Dr. T. Tokioka, of the Seto Marine Research,
Kyoto University, for his help in sampling the sea water.
LITERATURE CITED
(1) Ernst, HorMANN. Brit. Chem. Abst., I. A. 99 (1938).
(2) BARDET, TCHAKIRIAN et LAGRAGE. Compt. rend., 206, 450 (1938).
(3) ISHIBASHI, SHIGEMATSU and NAKAGAWA. (In press.)
(4) ISHIBASHI and SHIGEMATSU. Bull. Inst. Chem. Res., Kyoto Univ., 27, 42
(1951).
(5) LYMAN and FLEMING. J. Marine Research, 3, 134 (1940).
A STUDY ON ‘TEMPERATURE AND SALINITY OF
THE SURROUNDING WATERS OF TAIWAN
By Cuu Tsu-yao
Taiwan Weather Bureau, Taipei, Taiwan
I. INTRODUCTION
Taiwan lies 150 km. off the coast of Fukien and is now a province
of China. It consists of a main island and many small ones. The main
island, widely known as Formosa, resembles a spindle extending from
north to south with a coast line about 1500 km. The Penghu or Pes-
cadores is a group of islands in the middle of the Taiwan Channel.
Other small islands such as Penkiayu, Lanyu, Lotao, etc. are found in
the vicinities along the north and east coasts of the main island.
The main island of Taiwan stands on the edge of the continental
shelf of Asia and some of the small islands are of volcanic origin. The
depths of the surrounding waters are, therefore, strictly different be-
tween the east and west sides of the island. In the Pacific ocean off the
east coast, the slope of the bottom is very steep and the deep water
reaches close to the island. At some places such as Hwalien and Tai-
tung, the bathymetric line of 3000 meters is within 100 km. from the
coast. On the other hand, the water in the Taiwan Channel is very
shallow and in most parts of it the depths are below 100 meters. The
topography of the bottom is very irregular and numerous rocks, reefs
and banks rise from the bottom and some of them are exposed to the
open air during the time of low tide. In the East China Sea off the
north coast of the island, the depths are also less than 200 meters. It
is much deeper in the South China Sea where we can find the deep
water over 3000 meters.
Taiwan is located in the subtropical zone of the West Pacific where
the North Equatorial Current turns northward and becomes the source
region of the “Kuroshio” with properties of warm current. The main
{low of the Kuroshio passes along the east coast of Taiwan and curves
eradually northeastward far to the coast of Japan. A small part of the
Kuroshio runs westward through the Bashi Channel and, after passing
it, divides to two branches. One enters into the South China Sea while
the other runs northward around the west coast of the island and re-
joins the main flow of the Kuroshio in the East China Sea. Along the
coast of Fukien province, there is a different system of current running
from north to south. It has the name of China Coastal Current, and
821
822 EIGHTH PACIFIC SCIENCE CONGRESS
it originates from the coast of North China and is reimforced by the
outflows from the Chinese mainland. ‘The properties of this current
vary in different seasons. The water temperature is much higher dur-
ing the summer time and cooler in the winter time.
The climate of Taiwan is mild with a small seasonal variation of
air temperature, but the distribution of rainfall is variable at different
places. During the rainy season there are great outflows from the
island which influence greatly both the water temperature and salinity
along the coast.
With the vast area of outstretching waters surrounding the island,
Taiwan is a suitable place to serve as a base ground for oceanographical
investigations. Owing to the shortage of funds and technical experts,
research works have not been conveniently carried out during the past
few years. The writer can only make a brief study on the distribution
and seasonal variation of water temperature and salinity of the sur-
rounding waters of Taiwan with all the data available.
II. SuRFACE WATER TEMPERATURE AND SALINITY ALONG THE COAST
Coastal observations of water temperature and salinity are made at
nine stations situated all around the island as shown in Figure 1. The
average monthly values of each station are listed in Tables I and I,
which have been prepared from records covering more than ten years.
At the station of Penkiayu, which is situated at the coast of a
small island some 100 km. off the north coast of the island, the water
temperature is similar to the open seas. It reaches its minimum in
February and maximum in July with a yearly mean of 23.2°C. and a
small annual range of 7.5°C. The seasonal variation of salinity is also
small and the yearly mean is 33.86 °/ 9.
The stations of Fukuikiao, Keelung and Bidiukiao are all found
on the north coast of the main island. At these places the water tem-
peratures are influenced by the outflows from the island. Their annual
ranges are greater than Penkiayu, 1., 12.2°C. for Fukuikiao, 10.9°C.
for Keelung and 10.0°C. for Bidiukiao. The minimum and maximum
water temperatures are also found in February and July respectively.
Mean values of salinity are little lower than Penkiayu; they are also
influenced by outflows from the island.
Along the east coast of the island, there are two stations, Hwalien
and Singkang. These two stations approach more to the south and the
warm current of Kuroshio comes very near to the coast. It makes the
water temperatures a little higher and the annual ranges are 5.8°C. for
Hwalien and 4.9°C. for Singkang. The salinity of Hwalien is 32.34 °/o,
and that of Singkang is 34.07 °/ 0.
TEMPERATURE AND SALINITY—WATERS OF TAIWAN $23
The station of Ngulerbei is situated at the south tip of the island
stretching into the Bashi Channel. The water temperature is high and
the annual range is small, that is 25.5°C. and 6.0°C. respectively. The
mean salinity is 33.89 °/,, with a small seasonal variation.
Kiaoshiung is a station along the southwest coast of the island
facing the Taiwan Channel. The yearly mean of water temperature
of 25.7°C. is the highest value among all the stations, and its annual
range of 8.0°C. is also higher than the stations along the east coast.
The seasonal variation of salinity is very much pronounced as it
reaches its maximum of 33.82°/,, in December and falls even to
24.07 °/,. in August. ‘The reason is that at the southwest part of the
island, it is very dry during the winter time and there are almost no
cutflows at all. But during the summer time the rainfall is quite
heavy.
Peitao is a small island of the Pescadores located in the middle
part of the Taiwan Channel. At that station, the yearly mean water
temperature is 23.3°C., lower than at the southern stations of the
main island. ‘The annual range of 8.9°C. is little higher. ‘This district
is the most dry region of Taiwan, rainfall is very scarce during all sea-
sons. ‘Therefore it shows a higher monthly salinity and has a mean
salinity Of 33.82 °/ oo.
III. SuRFACE WATER TEMPERATURE AND SALINITY OF THE OPEN SEAS
As the oceanographical investigations of the surrounding waters
of Taiwan were interrupted, from the beginning of World War II,
we can only find some records of surface water temperature and salinity
observations made before the War. The writer has made an exami-
nation of these data and gives a brief discussion below.
The surface water temperature of the surrounding waters of Tai-
wan is greatly influenced by the Pacific warm current of the Kuroshio
and by the China Coastal Current. During the winter time, the tem-
perature of the coastal current is much lower than that of the Furoshio,
and very close isotherms are arranged from the coast of Chinese main-
land to the southeast. In summer, the water temperature of the coastal
current is warmed almost up to the same level as the Kuroshio. There
are only a few lines of isotherms which make the distribution very
simple.
In Figure 2, showing the distribution of water temperature in
February, we can see the lowest temperature of 10°C. along the north
part of the China coast. It increases gradually southeastward and
reaches the maximum temperature of 26°C. off the southeast coast of
the island. At the south entrance of the Taiwan Channel, isotherms
824 EIGHTH PACIFIC SCIENCE CONGRESS
curve to the north near the coast of Taiwan, which shows the warm
water entering into the Channel. At the north entrance of the Chan-
nel, the isotherms curve to the west. It also shows the influence of warm
current but there are still outflows from the Channel close along the
north coast of the island.
The water temperature of the China Coastal Current in May is
warmed up and we can find the lowest temperature of 20°C. along the
north part of the coast (Fig. 3). It increases gradually southeastward
and reaches its maximum of 28°C. In the Taiwan Channel the iso-
therms are parallel to the China Coast, but they turn gradually to pa-
rallel with the latitudes off the south and east coast of the island. From
this distribution of water temperature we can find out that there are
still inflows of warm current at the south entrance of the Taiwan Chan-
nel along the west coast of the island. But at the north entrance of
the Channel the China Coastal Current seems more intense and the
warm current leaves farther to the east.
The distribution of surface water temperature in August, which
is shown in Figure 4, looks very simple. ‘There are only two lines of
isotherm in the figure. The isotherm of 27°C. is along the north part
of the China Coast, while that of 28°C. separates the coast of the is-
land of Taiwan. ‘They all run from southwest to northeast. In this
month, the water temperatures of both the China Coastal Current and
the Kuroshio reach their maximum, but the former, coming from the
higher latitudes, is comparatively cooler than the latter, which comes
from the lower latitudes.
In the month of November, the surface water temperature along
the north part of the China Coast drops down to 20°C. It increases
gradually to the southeast, as shown in Figure 5, in which we can
find that the isotherm of 26°C. is very close to the south and east coast
of the island. But the isotherm of 27°C. is far to the southeast, leaving
a great space to the isotherm of 26°C. From this manner of distribu-
tion it may be considered that the temperature of the main flow of the
Kuroshio is around 27°C. and is mixed with the cooler water in the
Taiwan Channel and the East China Sea.
The seasonal variation of salinity of surface water in surrounding
waters of ‘Taiwan is not so great as that of temperature. ‘The writer
gives two sketches here to show the distributions of salinity in Febru-
ary and August. In Figure 6, showing the distribution of salinity in
February, we can find that in the east and south of ‘Taiwan the salinity
is more than 34.5 °/,), which coincides with the salinity of the Kuro-
shio. In the Taiwan Channel, the salinity decreases gradually toward
TEMPERATURE AND SALINITY—WATERS OF TAIWAN 825
the coast of the mainland of China, reaching a lowest salinity of
30.0 °/o9, which is influenced by coastal waters.
The salinity off the east and south coast of the island in August
is a little lower than in February. The iso aline of 34.5 °/,, leaves farth-
er to the east, as shown in Figure 7. ‘The lowering of salinity at that
region is contributed to the plentifulness of rainfall during that season.
Very close to the coast of the island of ‘Taiwan we find still lower sa-
linity below 32.0°/,, and 33.0°/,,. It may be contributed to the effect
of outflows from the island. In the Taiwan Channel, the salinity de-
creases toward the coast of the Chinese mainland, where we find the
lowest salinity of 31.5°/,,. This value is a little higher than in Feb-
ruary. It is, perhaps, the result of intense evaporation effected by the
high water temperature.
IV. CONCLUSION
From the above discussion, we can see the general feature of the
seasonal distribution of surface water temperature and salinity in sur-
rounding waters of Taiwan. It is clear that these variations are greatly
influenced by the properties of different systems of currents. Unfor-
tunately, we can not get enough data to find out the vertical distribu-
tion of these two elements and, therefore, it is impossible to form a
whole idea about the nature of the currents. It needs more data of
observation and further investigations to solve the problem.
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ON THE FLUCTUATION OF THE KUROSIWO
AND THE OYASTIWO
By ‘Tosio NAN’NITI
Meteorological Research Institute, Tokyo, Japan
ABSTRACT
Using the area occupied by the oceanic current in a fixed section,
the author represents on a graph the intensity of the Kurosiwo and the
Oyasiwo as mentioned in his previous paper. The occupied area has
one or two maxima a year. The period is about seven to nine months
as shown in accompanying figure.
1. INTRODUCTION
To represent the intensity of the Kurosiwo and the Oyasiwo nu-
merically, the author adopted substitute quantities which are easily
calculated; they are the ratios of the area occupied by the Kurosiwo or
the Oyasiwo to the whole observation area in the fixed section on the
parallel of 38°18’N. In the case of the Kurosiwo the calculation is
limited to 300m depth, and in the case of the Oyasiwo to 600m
depth.t The author will copy the values published by the Central Me-
teorological Observatory for the sea conditions, and will compare these
with his quantities, the ratios of the Kurosiwo and the Oyasiwo.
2. COMPARISON OF THE RESULTS OBTAINED BY THE AUTHOR’s METHOD
WITH THE ACTUAL OCEANOGRAPHICAL CONDITIONS
The results obtained for the ratios of the Kurosiwo and the Oya-
siwo are shown in the following figure. If these values correspond to
the actual oceanographical conditions with small differences, we would
have an important means to represent and forecast oceanographical
conditions.
The actual oceanographical conditions quoted here were inves-
tigated by the usual method using the distribution patterns of tempera-
ture, chlorinity, etc.
We observed that the intensity of the Kurosiwo was less in 1949
than in the preceding year. In 1948 the Oyasiwo was somewhat strong-
er in early summer and late autumn, but it was weaker in other months.
On the other hand, the Kurosiwo was stronger, especially in summer,
and the warmer anomaly of the surface water temperature was largest
in August.2 The ratio shows that the Kurosiwo’s area was large in late
837
&38 EIGHTH PACIFIC SCIENCE CONGRESS
September and in October. Perhaps the ratio in August can be con-
jectured to be large from the tendency of the figure, but observations
were not done before September.
In 1949 the Kurosiwo had average or somewhat stronger intensity
in summer, and the warmer anomaly of surface water temperature was
largest 1n October. ‘The figure shows that the ratio of the Kurosiwo
had maxima in June and July, and that their value was usual
for summer maxima. Another maximal value appeared in Septem-
ber, after the rainy season. This was smaller than that of the preced-
ing year. This fact indicates that the Kurosiwo was weaker than in
the preceding year. In these years, the available data were scanty due
to the imperfection of our equipment.
In 1950 the Kurosiwo became stronger rapidly from April, with an
extremely warm surface temperature in summer. The warmer anomaly
of surface temperature, which was largest in May and August, was
limited to the somewhat upper layers in summer. ‘The Oyasiwo be-
came stronger rapidly in April, weakening from middle August and
growing stronger again in September. But it was still warmer in the
warm current region and colder in the cold current region than in the
average year. ‘The ratio of the Kurosiwo grew larger from April and
May, and it was very lage in August and September, growing smaller
rapidly in October and tending to zero in December. The ratio of the
Oyasiwo was large in spring and in early summer also, but it was small
in summer, growing large again from September, and reaching a maxi-
nium in December.
In 1951 the Kurosiwo became stronger rapidly from April, but
weakened from middle June to July; the temperature anomaly was low-
er than the average. But its temperature became higher again from
late July to August. It stopped to rise, maintaining the average or
somewhat lower value in September and October. But it became strong-
er from November especially and kept the intensity till February 1952;
so the warmer anomaly of temperature, warmer than those of 1950 and
1951, was observed in February, and this vigorous Kurosiwo weakened
in March and April. The Oyasiwo had iess intensity than that in the
preceding year in early Spring, but it became stronger in early July,
weakening in August and again becoming stronger in September, then
weakening from October till February.® The ratio of the Kurosiwo
grew large rapidly from April and was largest in June, growing smaller
trom July but larger again from November, becoming largest in Feb-
ruary, 1952.The ratio of the Oyasiwo had a maximum in December,
1950, and alter that it grew small and was smaller than in the preced-
ON THE FLUCTUATION OF THE KUROSIW) AND THE OYASIWO 839
ing year. It was large in July, September and late October, and small
again from November till February.
In 1952 the Kurosiwo was strong from the last decade of Novem-
ber till February and became strong again in early April along the
meridians 143°E and 149°E, reaching the average intensity in June
and July, but the warm current stopped spreading northwards in Aug-
ust at a lower anomaly of temperature. But it grew warmer again and
reached the average temperature in September. After that it had the
average intensity. The Oyasiwo was strong along the meridians 142°E
and 147°E in March and April. In August, the Oyasiwo ran south-
wards strongly along the 145°E meridian. The ratio of the Kurosiwo
became smaller from February and was generally small all year with a
maximum in September, which is of the average value in summer. The
ratio of the Oyasiwo had maxima in April, July and September.
The ratio of the Kurosiwo seems to vary periodically. If there
were a maximum in February, 1950, though it was not observed owing
to bad weather condition, the maxima of the Kurosiwo’s ratio have the
following time series: Oct. W9285.9; stl SIS OR -os web. e950) 7-5; Sept:
1950, 8.5; June NG ORS ECD A952 y/-osgocpt 9a.
The period is about seven—nine months. On the other hand, the
period of the wind stress shear is about six-eight months.’ The periods
of the oceanic current and the wind do not coincide with each other,
and the reason why the current’s period is lengthened will be found in
a complex combination of the wind-driven, thermo-haline circulation,
etc.
3. CONCLUSION
By the comparison mentioned in the above section, we can recog-
nize that the area occupied by the oceanic current is an important meas-
ure to represent numerically the intensity of the current or the oceanic
state, and the period of the Kurosiwo’s fluctuation is about seven—nine
months. Though we may have to make further investigation of the
difference in the periods between the Kurosiwo and the wind, it is cer-
tain that we have made a step toward the forecast of oceanic conditions.
(2)
(3)
(4)
(5)
(6)
(7)
FIGHTH PACIFIC SCIENCE CONGRESS
REFERENCES
NAN’NITI, T., 1951:On the Fluctuation of the Kurosiwo and the Oya-
siwo. Papers in Mteorology and Geophysics MRI 2, (1) p. 102.
Report on the State of the Sea adjacent to Japan, Central Meteorological
Observatory, 1949 (in Japanese).
WOE Cit 4 (2) 4 L950:
Report on the Oceanographical Investigation and Study on the Long-
range Forecasting in Japan, Centr. Met. Obs. 1951 (in Japanese).
loci cuts (4) 9 a28
Letter from Mr. J. Fukuoka (Centr. Met. Obs.).
NAN’NITI, T., 1952: On the Fluctuation of the Kurosiwo and the
‘Wind. Journal of the Oceanographical Society of Japan, 8, (1) p.
9
DEB
ON THE FLUCTUATION OF THE KUROSIWO AND THE OYASIWO 841
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A REPORT ON THE OCEANOGRAPHICAL OBSERVATIONS
IN THE ANTARCTIC OCEAN CARRIED OUT
ON BOARD THE JAPANESE WHALING
FLEET DURING THE YEARS
1946-1952
By Masao HAnzawa and TakrEo TsucHIDA
Oceanographical Section, Central Meteorological Observatory
Tokyo, Japan
ABSTRACT
The chief characteristics of the oceanographical conditions of the
Antarctic Ocean given in the present treatise are founded on the obser-
vations taken on board the Japanese whaling fleet during the years 1946
to 1952. Among many interesting facts found by the Japanese Fleet,
we may mention these significant points.
1) In the Antarctic Ocean, the temperature and chlorinity graph
of the sea surface increases in the shape of a parabola as the
distance from the pack-ice line increases.
2) Ocean currents computed from dynamic calculation near Scott
Island in 1949 show eastward flow to the north of 67°S, and
southward flow along the 180° line to the south of 67°S.
3) The insignificance of the Antarctic circumpolar water is due
to bottom topography and to small clockwise circulations.
4) The boundary of two currents is a good whaling ground, even
in the Antarctic Ocean; and in the homogeneous water area
good whaling is not expected.
845
A NEW JAPANESE G.E.K.
By K. Supa, Kuropa-Masao, D. SHoji and SAWAYANAGI-FUMIWO
Hydrographic Office, Tokyo, Japan
(1) INTRODUCTION
An insulated conductor is drifted along the ocean current flows,
cutting the geomagnetism; then there must occur an electric motive
force by Faraday’s electro-magnetic induction law. If this e.m.f. can be
picked up, the velocity of the conductor, which is the same as that of
the current, may be known, as the distribution of the geomagnetism
is already known all over the world. Electromotive force will be in-
duced in the current too, but it is dropped as negligible, because the
sea water is conductive and its volume is immensely large, even in the
superficial part, as Stommel proved. If both ends are shortened to
the sea water, an electric current flows through the wire and sea water.
We utilise this e.m.f. for measuring the velocity of the current as
above mentioned.
In practice, there remain the following difficulties:
1. Sea water is an electrolytic solution, so a contact of metal intro-
duces an ionization potential and the measuring is disturbed very much.
We conquered this trouble by using a special electrode of silver-silver
chloride.
2. The resistance of these electrodes is very high and the electric
current decays them even as small as less than 0.1 micro-ampere. These
problems have been easily solved since the electronic potentiometer was
produced in Japan.
We composed a system of measuring apparatus from a couple of
specially designed electrodes, an electronic potentiometer, a set of lead-
ing cable made by special order, and a switch pannel having switches,
electric condensers, etc.
Some confirming experiments were done very cautiously on the
characteristics of the electrodes on the temperature effect, density effect
of salt water and some points of handling for practica! uses.
(2) PracricaL MeTHop oF MrAsuREMENT
The electrodes are connected directly to the pannel board of the
potentiometer by two lines of the specially made cord of a single core.
The length of the cord is 200 m. and 100 m. respectively for the elec-
845
846 EIGHTH PACIFIC SCIENCE CONGRESS
trodes, i.e. the latter is 100 m. distant from the former. ‘Then they are
driven into sea and the cord is tied to the ship as the shorter electrode
stays about 100 m. from the stern of the ship.
These works are conducted when the ship is running. When all
have been prepared well, measurements are begun.
At first and at last, the zero point confirmed by the longer cord
is shortened till the length becomes the same as that of the shorter one,
i.e. the two electrodes lie side by side. We got the constancy of the
zero point in the range of 0.2 mV or less, which corresponds to about
0.1 kt of the current velocity.
After confirmation of zero point, we prolong the longer cord to
full length. Then the meter indicates some millivolt, which shows
the e.m.f. produced by the component of the ocean current perpendt-
cular to the direction of the ship course. Then we turn the course to
another direction, preferably near right angle. When the needle of
the meter sets in the new direction, it indicates the e.m.f. of the com-
ponent perpendicular to the new direction. Under the assumption that
the current is constant during the turning of direction, or the two com-
ponents can be considered to be those of the same vector of the current
velocity, we can compose the total velocity from the two components of
velocity and the direction of the course of the ship, which is known by
the compass.
The composition of these vectors 1s, however, a litle different from
the ordinary method. We draw the respective vectors of the compo-
nents, from the same point in the middle of turning. The scalor
amount is given from the reading of the potentiometer and the direc-
tion must have been informed from the bridge of the ship, whenever
the reading is taken. Then, the intersection of the two perpendiculars
from the respective points of the component vectors must be the top of
the composed vector, drawn from the same origin.
In such a way, we can measure easily the vectorial velocity of the
ocean current from the moving ship. For the check of these values, we
compared the values of the amount of the drift of a ship by the cur-
rent measured by our method and by calculation from the positions
of the ship at the beginning and the end. ‘The position of the ship
was confirmed by triangular survey by a sextant.
(3) PRACTICAL MEASUREMENT OF OCEAN CURRENT
1. Off the point Nojima-zaki.
Nojima-zaki is situated at the south edge of the Bohsoh Peninsula,
Chiba prefecture, Japan. The warm current “Kuroshio” flows along
A NEW JAPANESE G.E.K. 847
the south side of the main island of Japan and passes through the row
of Iz islands to Nojima-zaki. We attemped the first experiment of the
measurement on Kuroshio, off the Point Nojima-zaki.
Three square courses and two zig-zag courses were made as shown
in Figure 1. At every point of turning, the measurement was tried.
The velocities measured by our method are shown in the following
table. The points of survey stand in four rows, so the values may be
ciassified into four series. The series 4 farthest right is considered
to be near the edge of the current.
VELOCITY OF KUROSHIO OFF THE POINT NOJIMA-ZAKI
POSITION No. oF SERIES VELOCITY KT MEAN KT
left (north) 1 Ne, IB. a8} 1.37
middle 2 sy! ELS ey :
right (south) 3 ‘otmoudts eto eo 1.34 3
edge 4 0.8, Om 0.85
On the other hand, we found the amount of drift of the ship from
the difference between the positions, surveyed by the triangular method
to land, and those calculated from ship velocity, time duration and
direction.
At every drift is 1.1 kt, 1.3 kt and 1.4 kt, and the vectorial mean
is 1.26 kt. Comparing these values of drift of the boat with the former
values 1.37 kt, difference was found to be only 0.1 kt and the direction
coincided with the accuracy of the compass, 5°.
In conclusion, the accuracy of triangular survey by the sextan meth-
od is rough as known generally, but the two values coincided well.
Furthermore, the mean values of the three series of the G.E.K. method
coincide with each other very well. The individual values differ from
the mean values of the 1.37 kt, with the range of error as +0.25 kt
This accuracy has not been confirmed till now with more accurate meth-
ods, yet the statistical values will explain well about the accuracy.
2. Along Iz Isiand.
In the south of the Iv Peninsula, Shizoka Prefecture, there lies a
row of islands from north to south. We call them Iz 7 Islands. The
warm current Kuroshio flows through this row of islands from west to
east. For the second experiments, we surveyed Kuroshio around this
row of islands between two peninsulas, Bohsoh Peninsula and Iz Penin-
sula as shown in Figure 2. Figure 3 shows the recording chart. The nu-
merical figures show the time; those between arrows in middle circle
$48 EIGHTH PACIFIC SCIENCE CONGRESS
are the millivolt produced in the cord. 1.74 millivolt corresponds to 1
knot around this district. In this experiment, we found many new facts.
1) Kuroshio flows from S.S.W. to the nose of Iz Peninsula and
changes its direction to N.E.E. with a velocity of 1.7 kt to 1.3 kt.
2) Though we missed to survey well, it can be said from our
other results that this current collides against Ohshima Island of Iz 7
Islands and separates into two ways.
One tlows N.E. and reflects at the Sagami Bay to S.E. Another
one flows E. and passes through the south side of Ohshima, and changes
its direction to S.E. into the center of Pacific Ocean.
3) The former passes through between Ohshima and Nojima-zaki
to S.E. with velocity 1.3 kt.
4) It is imagined that a still part exists behind Ohshima Island,
as a center of vortex.
5) A part of the two flows shown in 1) miay join after this vor-
tex and flows N.E.E. to some point off Nojima-zaki, which was sur-
veyed in the first attempt.
6) We found a current which flows S.E. with velocity over 3.5 kt
at a point about 34°20'N., 139°40’E. “This current comes, perhaps,
from a branch of the current through the south side of Ohshima shown
in 2). Details of this current are shown in Figure 4.
(4) CONCLUSION
1. We constructed a new G.E.K. with special silver-silver chloride
electrode, an electronic potentiometer, special cord made to order, and
other accessories.
2. The calibration shows that this has a good accuracy compared
with the drift method, surveying land points by a sextan to confirm the
ieal position of the ship.
3. Three series of the measured value by G.E.K. off the Point No-
jima-zaki show the same mean value 1.37 kt from observations of over
one dozen, and the individual values deviate +0.25 kt from the mean
value.
4. Survey with G.E.K. along Iz Islands showed many details about
the construction of Kuroshio.
A NEW JAPANESE G.E.K. 3549
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AUTHOR INDEX
BADER, RICHARD G. ........ Sipe {val
BARNES, CLIFFORD A. ...... 585, 686
BOHUKE ANMIES) Wn sc. acne ss 183
BOUIN RAROLE eae aecinine @ atak os 373
BRUUINEEAINTOND Rs eins ieee: 365
BUEN, FERNANDO DE .........-. 266
WAR TERA OINTAT Mig 3 au elle haere 200
CWREMENS HY Wie Ag) 3) 2505 ess os 121
DIAWISONG Hin YATE) Sle yee oe a: 489
TD YEAET op, ol neg RGAE oe toe ne en Le ee 499
DOU Me ePAR SG tector tid, ny Sates ens 571
IDOIMIAINIDAY JOSE GS) oy. oon) 417
VERRAN OE phe ycean oy. cco yeas 685
ETCHEVERRY-DAZA, HECTOR .... 246
UAW OKA ris Sit = sitniets ac tvece sees 787
GUARINIER nD inn eee tie oe ee ie 743
COSEINES WEELIAM YAU a. 20: 347
GRAHAM, HiRBERT W. ........ 673
CGUREEERMPdissss ce ees ke eee 208
IsDAg, AUNDNSIGON 6604s cone ae 493
ELAS THAD: eSRUCKO Wie ta... na 321
IREAINIZAWIAN IMIASIAO) Ges ce oe 843
ELAR DENBERGS ie De iy eae 457
AD Melissa ara cconce Una reac oe 314
LIVARKCAS, SOS ns ee ws HUG).
ELRYAINWAN YOOSIENIO! Su eis es se Aas 165
EL OUETSTER td Ie us piers Ae Sic ie 705
ISHIBASHI, MASAYOSHI ........ 817
JOHNSON, MARTIN Wi .....2-.. 379
JCA IMD Gol aati cool ilaieeo aie bearers 781
ICA AAIVIO TIO IN. eG naling a oets aoe PPXY)
KAWAMOTO, TAKEO ........... lacae
IISA, (Ile soocpoecconoc 3038
LCTSUAINIE iON) (ied Re este neha ape ene ee 189
TROND, GC cea Pe 403
OEZUIMT SIME. Eiegayirs sist cishe: a,evanacee 787
GR OONAWAN GELS ie wy cial cee hls 331
KeURODAWLOKUBEL anaes ce 4938
TRQGROIOA, MUSING) Gocccunnccedoe 845
ILINCOitiN, Ou 18k, soesssoeeae 686
ILRAVIAN, MOEN aoococoocoouone 609
WUAIOVA, JeoxOssete oookcoccsaoeue 234
WEARRS ROHN GC. suicuc ues sse ne 1838
NATSU Ie VOSHDICET =. 55 seers 225
MUN ANDAR, SSHSUUAOO) “BOS Ea vege oc 391
MiEWER ROBERT Osl.540 5588 126
MiIVADT DENZABURO! 26) 52505 493
VEDA IASC OMe air ce ni as Aco 781
MIYAZAKI, MASAMORI ......... lio
VOR TWA (OSU TIS teers ee nee Ot
NAKAGAWA, YASUHARU ....... 817
NAKAMURA, HIROSHI .......... 165
INPAUCAYN Os VIB flee Se erate vas maa i 787
INVAIN NIT Tepe waee nets nse dhcp casei 837
OKADA GAT OHIRO! ee sa! ae 391
OSORTO=APAR ATT Bea as aie oe 253
JEYNINIECRONG, UINIG IK 5 Sen poke aueds 294
PAQUETTE, ROBERT G. ......... 585
IPERTERSSON, HIANS =... .552 4... 637
IPOWLSENASETR Gp Vike ys eis ee 241
TERON GADD Gp ANG NYG 1 Bio ie Gveteqees tonesteaen 359
TVATER AY, 2 Jie VEAURICH yn seer 686
REVEROS-ZUNIGA, FRANCISCO ... 280
ROCHEORD AD idl aaenvc a2 ahs slat 745
SAWAYANIG'-FUMIWO ......... 845
SCHAERER, MUlmNERS IBS 2.50. -5e 149
SCHUDIZS IEBONARD Pa. saee are: 4138
SCHWEIGGER, ERWIN .......... 801
Swinney, IDs Ibs sos edesocobs ae 461
SELTES OS OAR BH paracrine 131
SHEPARD] SHRAINCISm b> 6 cian sn.) 743
SHIGEMATSU, TSUNEBOBU ...... 817
OIETO UIT ais heroes ttre seees Shey 619, 845
SUD IAP Kerra errs ch raeun een! a 619, 845
SUGIURAM INGE Mp hae 8 oka cls Sc 781
HIVAUNGT Tt KG sare nrenrcn msc ovS ia ssn iene 215
THOMPSON, THOMAS G. ....... 3
SU CHTD Apo IVAUCEO) 2 Ss ye cteeeoee 843
SU RNEN ON CHIWiet vey ae earn or 821
IMMHING, HORI 1, Gacoocspcccc 3, 643
WIA, WGeoneGHW NN Sooo ooaeooue 663
VIALARD-GOUDOU, A. .......... 208
WOLSKY, ALEXANDER .......... 505
WOOSTER, WARREN S§. ......... 679
WAINIAGAW Ala tli iiarener ney! inj so aoe « 215.
NGAINIE:Z/ mle ARI MIBINIDO Ateneo). 287
CORRIGENDA
Page 369—last line, for “Colloqgium” read “Colloquium”
Page 431—line 27, for “fuscopuntata”’ read “fuscopunctata.”
Page 446—line 3, for “Kehler” read “Koehler.”
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