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Richard H. Backus

April, 1988

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l^ou Manon — University of Miami
Pacific Bill fish Expedition

PRf:LI,\iINAR^' REPORT
¥ OR 1954

LUIS R. RIVAS

Scientist in charge of Expedition

BIOLOGICAL
LABORATORY

LIBRARY

WOODS HOLE, MASS
W. H. 0. 1.

F. G. WALTON SMITH
Director

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CORAL GABLES, FLORIDA • JUNE, 1955 • 55-8 • M.L. 9696

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TABLK «F I IKVTKATS

PAGE

INTRODUCTION 5

Summary of Objectives and Results 5

Personnel and Equipment 7

Acknowledgements 10

GENERAL ACCOUNT 12

Chile 12

Peru 14

Ecuador 17

ICHTHYOLOGICAL STUDIES 19

Other Biological Observations 25

COMMERCIAL FISHERY SURVEY 26

General 26

Chile 28

Zone I - Iquique 29

Zone II - Antofagasta 30

Zone III - Coquimbo 31

Fishing Methods 33

Boats " 33

Fishing Equipment 33

Peru 37

General 37

Geography 39

Fishing Methods 41

Experimental Longline Operations 43

Economy 45

Ecuador 45

General 45

Geography 48

Fishing Methods 49

Economy 52

Conclusions 53

PLANKTON STUDIES 54

List of Plankton Stations 55

HYDROGRAPHIC DATA 57

Cabo Blanco 57

Salango 61

Iquique 63

Summary and Recommendations 64

INTRODUCTION

Sum mar If »/ Ohjvfiivvs and Kvsahs

DURING THE PAST Several years the Marine Laboratory of the University
of Miami has been engaged in research into ocean game fishes, not
only in the north Atlantic, but also as far afield as Australia, New Zealand,
South Africa and Panama. An extension of this work into the waters of the
Pacific coast of South America was made possible through the generosity
of Mr. and Mrs. Lou Marron, who provided not only the financial support
necessary but, together with Mr. and Mrs. John Manning, self-sustaining
members of the expedition, also contributed a considerable amount of time
and energy to the organization of the field arrangements.

Since it was intended that the expedition should continue for several
years, the first year's work, carried out off the coasts of Chile, Peru and
Ecuador, was planned as a preliminary investigation, the results of which
might be used as the basis for more elaborate and detailed studies in the
future. Because of this, the principal accomplishments of the 1954 expe-
dition were the detailed measurement and study of the anatomical features,
breeding condition, and food contents of broadbill swordfish, black and
striped marlin. It is believed that the expedition has set some kind of a
record in the number of such fish ever to be scientifically examined in the
course of a single expedition.

The results of this suggest that striped marlin do not spawn off northern
Chile during the period of the expedition and that the females are consid-
erably heavier than the males. It was also noted that striped marlin in these
waters are decidedly more interested in taking bait while in water of higher
surface temperatures. The natural food, as shown by analysis of stomach
contents, appears to be restricted to squid. Although striped marlin are
taken off Chile during almost the whole year, they are far more abundant
from October to June. Oft' northern Peru they appear to be much more
abundant from December to June. Striped marlin off the coast of Ecuador
appeared to be immature.

No black marlin were found in Chilean waters. Off Peru almost all these
fish were female and none in spawning condition. It appears that black
marlin are more plentiful here during June and November and scarce dur-
ing the remainder of the year. The food of these fish was widely varied.

The broadbill swordfish taken off Chile were apparently all females and
not in spawning condition. They appear to be most numerous from July to
October off Cabo Blanco, where they form an important commercial catch;
but off Chile, May and June appear to be the months of greatest abun-
dance. It appears likely that the swordfish form a single population which

• 5:

migrates northward from Chile to Peru during the (northern) summer, and
that they move off into unknown spawning grounds during the (northern)
winter.

Along with the direct examination of billfishes, plankton samples were
taken for a study of life histories and in order to determine the general
nature of the biological conditions of the waters from Chile to Ecuador.
Physical measurements were made of the surface and underlying waters in
order to obtain a preliminary idea of the desirable objectives for future
hydrographic work. The ultimate purpose of this is to determine the man-
ner in which physical oceanographic conditions such as currents, wind
drifts, upwellings and associated temperature and salinity change, affect the
biological content of the waters and consequently, the migrations, feeding
habits and distribution of the billfishes.

The plankton samples were rich, particularly at the more offshore sta-
tions, but were disappointing in the comparative absence of young or larval
fishes. Since one of the objectives of the expedition was to obtain material
for life history studies, it is believed that future work of the expedition
should allow for plankton collections in December and January. Since many
fishes of the northern hemisphere spawn in early summer, there is reason
to believe that the same may be true of the southern hemisphere. This was
borne out by the gonad examinations.

Since the commercial fisheries of the entire coast include the billfishes
and since commercial fisheries are, in certain ways, very important indices
of organic productivity, a general study was also made of commercial sea
fishery operations in Chile, Peru and Ecuador. A general account of this
is given in this report with observations on the vessels, gear and methods
employed. From this it appears that further information on the hydro-
graphic conditions could be of value both in developing the fisheries and
in ensuring wise control and management of these resources. An experi-
mental longline operation was carried out in Peru with the help of the
Wilbur-Ellis Company and under the supervision of Mr. Donald Bates of
that company.

Preliminary examinations of the hydrographic data suggests that the
Peru Current extends north as far as Isla La Plata, Ecuador, as a sub-
surface current, overlain by a southward drift of warmer waters from the
equatorial countercurrent and Panama Current complex. The surface
boundary between the Peru Current and the Equatorial countercurrent
was located somewhat north of Cabo Blanco and the warm branch of the
eddy, first observed by Gunther off Arica, was found to extend as far as
Iquique and south.

The present report is of a preliminary nature and much of the data col-
lected still remains to be analyzed. It is therefore necessary to point out

6 '

that conclusions drawn are of a tentative nature, subject to modification as
the work ot analysis proceeds, and as further field work provides new ma-
terial for study. The principal objective of this report is to make available
the factual information and to provide a general basis upon which plans
for future field work may be laid.

Figure 1. The 40-foot cruiser Explorer, especially designed tor the
expedition and bui!t by Wheeler Shipyard Co.

Pvrsintnvi and Kquiptnvni

The work of the expedition was under the leadership of Mr. Luis R.
Rivas, who also was responsible for the ichthyological studies and for the
direction of field investigations off Chile and Peru. Dr. F. G. Walton Smith
directed observations off Ecuador. Mr. and Mrs. Lou Marron, with Mr.
and Mrs. John Manning, were responsible for the capture of the greater
number of the billfish specimens examined. Travelling arrangements, the
location of field bases and general field management, were in charge of Mr.
Marron, assisted by Mr. Manning, who remained in the field during the
entire period of expedition. All members of the expedition gave assistance
in the collection of samples and in the measuring and examination of spec-
imens. Capt. Howard Thuet, and Mrs. Thuet, field secretary, were respon-
sible for keeping numerical data and logs.

• 7

Plankton samples were examined on their return to Miami by Mr. Gil-
bert L. Voss and Mrs. Joan Clancey. Hydrographic data were analyzed by
Mr. Frank Chew. Commercial fishery surveys in the field were made by Mr.
John Manning, with the assistance of Mr. Rivas under the direction of Dr.
Clarence P. Idyll. The present report is based to a considerable extent
upon various government reports and similar sources of statistics.

Figure 2. Mrs. Eugenie Marron taking surface temperature otT the

coast of Chile.

During operations off the coast of Chile, Mr. Eduardo Ormefio Valen-
zuela acted as official observer for the Government of Chile. Commander
Jose Barandiaran and Mr. Felipe Ancieta were appointed in a similar ca-
pacity by the Peruvian Government.

For the most part the expedition was land based, with trips offshore of
one to seven days' duration. Hotel accommodations were available in Chile
at Iquique. In Peru quarters were provided at Talara through the kind co-
operation of the International Petroleum Company. Docking facilities were
provided at Cabo Blanco by the Lobitos Oil Company. In Ecuador, living
quarters were made available to the expedition through the kindness of Mr.
Forrest L. Yoder and Mr. E. Hope Norton of the Ecuadorian Corporation.
Mr. Emilio Estrada gave valuable help in setting up these arrangements.
It would otherwise have been impossible to carry out shore based work oft"

8 •

this isolated part ol the eoast where no adequate hotel aecommodations
exist and living conditions are generally primitive.

Most of the work was carried out from an especially-designed 40-foot
cruiser, built by Wheeler Shipyard Co., under the direct supervision and on
order by Mr. Marron (Figure 1 ). Capt. Walter Gorman and Capt. Howard
Thuet served as masters of the cruiser, being responsible for its continued
operation and also aiding in many ways with certain phases of the scientific
work. At various times other vessels were chartered by Mr. Marron or

Figure 3. Mr. Lou Marron with giant squid taken ofT Iquiquc, Chile.

loaned to the expedition.

The 40-foot cruiser, christened Explorer, features many items designed
for the purposes of the expedition. Included amongst these is a lifting boom
with a capacity of 2,500 pounds, extra heavy towing chocks, automatic
pilot attached to both cockpit and topside controls, Bendix depth gauge,
Taylor temperature gauge permitting the taking of ocean temperatures
while running, a special live-bait well, a deep freeze with a capacity of 1 6
cubic feet, and a completely new type of marine radio telephone.

Acknowledgments

Success of the expedition was made possible, not only through the hard
work of the sponsors and of the scientific staff, but also as a result of the
kind cooperation of a considerable number of individuals and agencies
who gave freely of their advice and assistance, both in the planning and
outfitting of the expedition and in the actual field operations. It is not
possible to name all of these, but the following brief list is representative
of the many to whom it is desired to accord grateful acknowledgments.

Representatives of the governments of Chile, Peru and Ecuador, for
their continuing cooperation, and the personal interest shown by their
excellencies, the ambassadors and the consul-generals in New York and
Miami, and their officials in South America.

W. R. Grace Company and the Grace Steamship Line, whose agents in
South America facilitated arrangements, and who handled and shipped the
Explorer from New York to Iquique, Chile, and also the subsequent ship-
ping of the cruiser to Peru and Ecuador.

Pan American World Airways System who put the facilities of their
organization at the disposal of the expedition, as well as aiding in trans-
portation and contributing a life raft for use aboard the Explorer.

Panagra (Pan American-Grace Airways, Inc.) for their contribution,
cooperation and assistance as well as putting their facilities and personnel
at the disposal of the expedition.

Wheeler Shipyard for building the Explorer, and special design of the
cruiser.

H. W. Remerscheid, vice-president of the Bell & Howell Company,
Hollywood Division. J. W. McAdams and their able staff, for their splendid
cooperation. Moving picture records of the expedition were filmed entirely
with Bell & Howell Company equipment.

Hudson American Corporation of New York, a subsidiary of Claude
Neon, Incorporated, for supplying and installing radio telephone aboard
the Explorer, and assigned one of their chief engineers for this purpose.

Dr. Norwood L. Simmons, chief engineer of the Hollywood Motion
Picture Film Division of the Eastman Kodak Company, for his technical

IQ •

advice and assistance. Also, George H. Gibson and Leslie J. Baker of
W. J. German, Inc. Tiieir help has been invaluable.

Johnson Motors Company for their contribution to the equipment of
the expedition, their interest and their appreciation of the research to be
undertaken by the expedition.

The Cortland Line Company, Gladding Line Company, Gudebrot
Brothers Company, and the Ashaway Line & Twine Manufacturing Com-
pany, for supplying fishing lines.

The Bendix Company for instruments, advice and cooperation in con-
nection with electrical installations aboard the Explorer.

International Petroleum Company, for facilitating arrangements for oil
and fuel supplies in Central and South American countries, and as hosts of
the expedition during the stay in Talara.

Richard F. Kelly of Amrocta Company, for making contacts and expe-
diting the movement of equipment.

Lobitos Oil Company, for the use of their dock at Cabo Blanco and for
anchorage.

Assistance and scientific cooperation in the field work is acknowledged
elsewhere in the text.

11

u K X E n A L A c: C O IJ X T

Chilp

MR. AND Mrs. John Manning and Mrs. Jane Thuet began collecting
marlin and swordfish off Iquique (Figure 10) aboard the chartered
cruiser Marlin on April 22, 1954 and continued to June 13. The expedi-
tion vessel Explorer arrived in Iquique on May 2 and Mr. and Mrs. Lou
Marron worked from her between May 4 and June 14.

Figure 4. Luis R. Kivas, scientist in charge and ichthyologist for the expedi-
tion, examining black marlin taken otf Cabo Blanco, Peru.

12 '

From the beginning of the expedition until June 14, a total of 36 striped
marlin and 7 broadbill swordfish were taken. These were measured from
length, girth, and weight by Mr. John Manning and Mrs. Thuet. Gonads
were also measured and samples preserved for microseopical examination.
Surface water temperatures and meterological data were taken during the
entire time spent at sea.

Mr. Luis R. Rivas took charge of the field work June 5, and with the
assistance of Mrs. Thuet, continued to make morphometric studies of the
billfish in greater detail and initialed a series of otTshore cruises for the
purpose of taking plankton samples for the purpose of life history studies.
On June 15 and 16, five stations were occupied, about 20 miles apart on a
line running due west of Iquique for about 100 miles. Plankton samples
were rich and surface temperatures fairly uniform between 16°C and
17.5°C. All billfish sighted were recorded.

Towards the end of June the number of billfish sighted dropped rapidly
and the next offshore traverse was accordingly made from Arica. Plankton
and hydrographic samples were taken at stations about 5 miles offshore,
about 40 miles apart, between Iquique and Arica; at stations 20 miles apart
along a line extending 100 miles due west of Arica; two, about 40 miles
apart on a 20° course from a point 100 miles west of Arica; and at a point
about 25 miles due west of Punta Pichalo. Surface temperatures were
almost entirely within a range of 15^C to IT^'C. Additional specimens of
billfish were obtained from commercial fishery operations at Arica.

A third offshore cruise was made during June 30 to July 2 to the south
of Iquique. Two stations were occupied at points about 40 miles apart on
a course of about 245° extending from Iquique to a point approximately
100 miles due west of Punta Lobos. Six stations were occupied at points
about 20 miles apart on the line due west of Punta Lobos. A further station
was located about 5 miles west of Punta Banancos. The plankton samples
obtained during this cruise were particularly rich in larval and juvenile
fishes and adult lantern fishes (myctophids) up to three inches long were
captured. Surface temperatures were within a range of 14.5°C to 17°C.
Observations were made on billfishes, whales and giant squid, which are
very abundant in this area.

Among other interesting observations, the feeding habits of the thresher
shark (Alopias) were studied at close range oft' Arica. The presumed use
of the long tail for slapping and stunning fish (bonito) was actually con-
firmed by direct observation. Through the cooperation of Messrs. Scheib
and Navarro of the fish cannery at Iquique, specimens of various species
of scombrid fishes from adjacent waters were donated to the expedition
for study. These included various species of tuna and bonito whose racial
characteristics were hitherto unknown. While the Explorer was underway

• 13

during sea work, material captured by the trolling handlines was preserved
in the deep-freeze or measured aboard. In general, the sea was very smooth,
and working conditions were excellent.

Shore work, which includes mostly the measuring and dissection of large
specimens of billfish was conducted at a very convenient site on the water-
front. An excellent workbench was available, as well as a crane for hoisting
large specimens directly from the Explorer to the workbench. A large
storeroom, for the use of the expedition, at the Grace Company building,
one block from the Hotel Prat and four blocks from our water-front
installations, was provided.

The fourth and last cruise in northern Chilean waters was conducted in
the area west-northwest of Iquique, during July 5 and 6. Eight plankton
stations, spaced about 25 miles, were occupied during this cruise, which
covered 250 miles.

In accordance with the shipping date of the Explorer to Peru aboard the
Grace liner Santa Rita, which had been set for July 10, field activities were
suspended on July 7 in order to prepare the cruiser for shipping. According
to Chilean law, the vessel and equipment had to be packed, inspected and
sealed by Customs from 2 to 4 days before shipping time.

Peru

The period, comprising July 13 to 17, was spent in Lima holding con-
ferences with government officials in connection with the expedition's
activities in Peruvian waters. Official documents clearing the Explorer for
operation in Peruvian waters, as well as Customs facilities were obtained.
Among others. Senator Manuel B. Llosa, Dr. Cristobal Vecorena, Director
of "Caza y Pesca,"' Mr. Robert O. Smith, Technical Advisor to Peru from
the Fish and Wildlife Service, Admiral G. Tirado, Peruvian Navy Chief of
Staff and Commander E. Zimic, Director Hydrographic Office of Peru,
were visited.

Mr. Felipe Ancieta was appointed observer for the expedition by the
Director of "Caza y Pesca," and Lieutenant Commander Jose F. Baran-
diaran. Director of the Navy Department of Oceanography, was appointed
as observer by Admiral Tirado. Mr. Ancieta is ichthyologist for the Peru-
vian government and has received some training at the University of
Michigan, mostly in fresh-water fishes. Commander Barandiaran, physical
oceanographer, who received his training at Scripps and at the U. S. Hydro-
graphic Office, was of the greatest possible assistance to the expedition,
particularly in view of his own contribution to the hydrographic knowledge
of the area. Through the courtesy of Commander Barandiaran the oppor-
tunity was taken of visiting the well equipped oceanographic laboratory of
the Peruvian Navy at Caliao.

14 '

The Explorer was unloaded at Paita on July 19, and reached Talara
under her own power the next day (Figure 10). During July 21 through 23,
the scientific equipment was brought ashore and stored in a room kindly
provided by the International Petroleum Corporation. Housing facilities
for the members of the expedition were organized, and the Explorer's
engines overhauled. The kind cooperation of Mr. Murray Matheson, Man-
ager of I.P.C., and of Mr. Richard Goodwin of Grace Company is acknowl-
edged.

The port of Lobitos, 8 miles north of Talara ( Figure 10), being closer to
the fishing grounds off Cabo Blanco, was decided upon as a temporary
anchorage for the Explorer. She was moved to this point on July 24, and
exploratory cruises began on the same date. It was soon discovered that
the permanent, extremely rough condition of the sea would not allow the
undertaking of long offshore cruises. After a visit to Cabo Blanco on the
25th, it was decided to leave the Explorer there and utilize its more ad-
vantageous facilities as a permanent anchorage. In addition to being at the
doorstep of the fishing grounds, Cabo Blanco was located with regard to
proposed oceanographic cruises into the Gulf of Guayaquil to the north
and Punta Agujas to the south.

During the sixth trip out off Cabo Blanco on July 29, three plankton
stations were occupied. During the seventh trip, July 30, two plankton
stations were occupied.

On the basis of reliable information that sea conditions in the Gulf of
Guayaquil, immediately to the north of Cabo Blanco, would be much
better, it was decided to conduct a two-day cruise into that area during
August 2 and 3. Five plankton and three bathythermograph and salinity
stations were occupied during this cruise. Several patches of Red Tide
were investigated close to shore oft' Zorritos. Samples were taken and pre-
served. As predicted by our hydrographers, the ocean turned from very
rough to smooth north of Punta Sal (lat. 4° S) with a simultaneous rapid
increase in water temperature from 18°c. off Cabo Blanco to 23.7°c. off
Zorritos, 48 miles to the northeast. The various exploratory cruises from
July 24 indicated a decrease in temperature as one travels away from
shore and from north to south as one travels close to shore.

Arrangements had been made for the use of a tuna clipper from which
detailed hydrographic observations were to be made. These failed to ma-
terialize and the bathythermograph records were reduced in number due
to the difficulty of taking them by hand over the fish roller stem of the
Explorer. Off the coast of Chile this was not too difficult, since sea condi-
tions were fairly good. Off the coast of Peru, however, the sea was con-
tinuously of sufficient strength to handicap such work on a small boat.

In the Cabo Blanco area marlin were not too plentiful at first, but during

• 75

Figure 5. John Manning and Donald Bates, aboard purse-seiner Corsario,
during longline cruise off Mancora, Peru.

the period of August 5 to the 26, a good run of black marlin afforded
many specimens for study. No more marlin were available for study be-
tween August 26 and September 12.

Arrangements were made, while in Peru, for a cooperative investigation
with the Wilbur-Ellis fishing company, through the courtesy of Mr. Donald
Bates. Longline gear supplied by the expedition was made up under Mr.
Bates' supervision in the form of an American modification of the Japa-
nese gear and was operated for the first time in these waters on an experi-
mental basis. In spite of the abundance of giant squid, the tests were gen-
erally successful. In addition to experimental fishing, the company kindly
made it possible to take bathythermograph observations and plankton
samples from the purse seiner Corsario.

Longline operations were continued from August 13 to October 15 but
the Explorer, manned by Walter Gorman and Howard Thuct, left Cabo
Blanco for work in Ecuadorian waters on September 12. The capture of
billfish was resumed in the waters between Salango and Isla La Plata,
Ecuador, on September 19, and continued until October 12, when the

76 •

expedition ceased work for the remainder of the }'ear.

tCfuador

Difficulties were experienced in Ecuador due to the comparative isola-
tion of the coastal area investigated and the primitive nature of land trans-
portation between Guayaquil and Salango. Thanks to the generosity of the
Ecuadorian Corporation and the help of Mr. Emilio Estrada, an hacienda
at Salango (Figures 9, 10) was made available for headquarters.

Since communication between the Explorer and the shore was by means
of bongos, native dugout canoes which are paddled through the surf, and
since the best ground for billfish was at La Plata Island, about 30 miles
offshore, several days at a time were spent at sea, with short intervals at

Figure 6. Giant nerve fibers of large squid taken in the Humboldt Current

off Iquique, Chile.

• 17

Figure 7. Mr. Lou Marron and Dr. F. G. Walton Smith, setting bathythermo-
graph for recording of subsurface temperatures otT the coast of Ecuador.

Salango for refueling and an occasional rest. From September 29 the field
work was under the supervision of Dr. F. G. Walton Smith.

While at La Plata the opportunity was taken to run offshore for a further
distance westward in order to take bathythermograph data and plankton
samples from waters beyond the continental shelf.

During the stay in Ecuador a number of fishes caught by natives from
their bongos in the course of commercial operations were examined but
fishing in general was poor. Of 9 black marlin sighted, only I was caught

18 •

and of 7 striped marlin, only 2 were landed. Two sailfish were also cap-
tured. No broadbill swordfish were seen.

At the termination of this work the Explorer was shipped to Panama for
refitting and storage until plans could be made for work during the follow-
ing year.

I ril T H Y €M. 4M; I C A I. STUDIES

IN ORDER to obtain specimens for study a total of 123 days were actually
spent at sea in angling operations from April 27 through October 12. In
addition to 54 days fishing from the Explorer in northern Chile (April 27
through July 6) a chartered cruiser, the Marlin, was used for the same
purpose during 31 days. During the period of work off northern Peru, 45
days were devoted to angling operations, from July 24 through September
10. Ofif Ecuador, 24 days were devoted to angling from September 19
through October 12.

During the angling operations (54 days) off northern Chile (Figure 10),
361 striped marlin (Makaira fnitsukurii) were sighted. Baits were pre-
sented to 185 and 107 strikes were obtained. Only 75 fish were hooked and
45 were actually landed. During the same period, 93 broadbill swordfish
{Xiphias gladiiis) were sighted, baits presented to 56 and 27 strikes ob-
tained. Only 17 fish were hooked and 11 were actually landed. No black
marlin (Makairi marlina) or sailfish (Istiophorus greyi) were seen during
the expedition's operations off northern Chile (April 27 through July 6)
The area covered in northern Chile (about 16,000 square miles) com-
prised about 1 60 miles of coastline, from Arica to Punta Lobos, and up to
100 miles offshore. Visibility and sea conditions were generally good, and
no rough seas encountered. No blind trolling for billfishes was conducted in
Chilean waters. Baits were presented only after the fish had been sighted.

Off northern Peru, only 3 striped marlin were sighted during the angling
operations in these waters (45 days). Baits were presented to only one,
and although a strike was obtained, the fish was not landed. During the
same period 34 black marlin were sighted, baits presented to 19 and 8
strikes obtained. Only 6 fish were hooked and 2 were actually landed.
Only 4 swordfish were sighted in Peruvian waters and baits presented to
three with no strikes obtained. No sailfish were seen from the Explorer
during the expedition's stay in Peruvian waters (July 24 through Septem-
ber 10) but 2 specimens captured by commercial fishermen were seen at
the Port of Mancora on August 15. The area covered in northern Peru

• 19

(about 2450 square miles) comprised about 70 miles of coast line from
Talara to Zorritos and up to about 35 miles offshore. Most of the angling
activities, however, were conducted in the vicinity of Cabo Blanco where
marlin appeared to be most abundant. In addition, continued heavy seas
prevented the expedition activities from covering more extensive grounds.
With very few exceptions, no blind trolling for billfishes was conducted in
Peruvian waters. In Chile, baits were presented only after the fish had been
sighted.

In Ecuadorian waters, 7 striped marlin were sighted during the angling
operations (24 days) from September 19 through October 12. Baits were
presented to 4 of these, all of which struck, but only 3 were hooked and 2
actually landed. Only 9 black marlin were sighted and baits were presented
to 8. Strikes were obtained from all of these, but only 6 were hooked and
only 1 was actually landed. All of the 4 sailfish sighted took the bait, but
only 3 were hooked and 2 were actually landed. No broadbill swordfish
were sighted in Ecuadorian waters. Blind trolling, rather than waiting until
the fish were sighted, was the method employed in Ecuador. Most of the
angling activities were conducted in the vicinity of La Plata Island.

Of the 45 specimens of striped marlin landed in northern Chile, 41 were
measured and dissected. Vertebrae were obtained for age studies and the
gonads and stomach contents analyzed. These specimens ranged from 170
to 396 pounds in weight (average 255 pounds) and 2260 to 2850 mm. in
fork length (measured from tip of lower jaw). Of the 27 specimens sexed,
12 (44 per cent) were males, and 15 (56 per cent) females. All the gonads
examined appeared to be in a resting condition, far from the ripe or
recently spent stage. This would seem to indicate that striped marlin were
not in the process of spawning off northern Chile during the period of
operations of the expedition. Females were considerably heavier (average
289 pounds) than males (average 236 pounds). The striped marlin oc-
curring in the waters off northern Chile appear to be much heavier than
those occurring off the west coast of Mexico and Southern California. In
these more northern waters, specimens rarely reach a weight of more than
250 pounds and usually average less than 200 pounds. The reasons why this
species is so much heavier in Chilean waters than in the north are as yet
unknown, but the oceanographic and biological data obtained during the
expedition may throw some light towards the solution of this problem. The
biometric data obtained will help determine whether or not the striped
marlin occurring in the eastern Pacific represent one or more races or
populations.

It is interesting to note that during the angling operations in northern
Chile, striped marlin were more interested in the bait and took it more
readily at higher surface temperatures and showed little or no interest when

20 •

Figure 8. Striped marlin jumping close to boat after being hooked by native
fisherman ofi^^ the coast of Ecuador.

surface temperatures were lowest. Surface temperatures during the angling
operations ranged from 16.2 to 20 degrees Centigrade.

The only other specimen of striped marlin studied during the expedition
was a small female 85 pounds in weight, and 1955 mm. in length, captured
off La Plata Island, Ecuador, on October 6. The size and condition of the
ovaries indicated that this specimen was probably immature.

Examination of the stomach contents of the striped marlin studied in
Chilean waters, showed that these fish were feeding almost exclusively on
squid.

Although only 3 striped marlin were sighted (none taken) during the
angling operations off northern Peru (July 24 through September 10)
interviews with local commercial fishermen and anglers familiar with the
area indicate that these fish are much more abundant during the summer
months comprising December through June. In connection with this, it is
interesting to note that although striped marlin are taken in Chilean waters
practically the year round, the species is much less abundant during the
winter months (late June through September). During the expedition's
angling operations in Chilean waters 284 individuals were sighted and 34
landed during the 35 day period comprising April 27 through May 31.
whereas only 77 were sighted and 1 1 landed during the 36 day period
comprising June 1 through July 6. The abundance of fish definitely de-
creased with the approach of winter and the lowering of the water tem-
perature. Striped marlin are called "pez aguja" by the Chileans.

As already indicated no black marlin were seen in Chilean waters and

• 21

so far as known none have been taken there by anglers. However, inter-
views with commercial fishermen revealed that at least a few specimens are
taken by them every year. These men can distinguish well between the
striped and black marlin and refer to the latter as "pez zuncho."

Twenty-six specimens of black marlin were measured by the expedition
in Peruvian (Cabo Blanco) waters, thanks to the splendid cooperation of
various other anglers whose catches were kindly donated for study.

All of the 26 specimens of black marlin available for study in Peru were
measured and dissected. Vertebrae were obtained for age studies and the
gonads and stomach contents analyzed. These specimens ranged from 418
to 1085 pounds in weight (average 770 pounds) and 2755 to 3475 mm. in
fork length (measured from tip of lower jaw). Of the 26 specimens sexed,
only 1 (4 per cent) was a male, and 25 (96 per cent) females. All the
gonads examined appeared to be in a resting condition far from the ripe
or recently spent stage. This would seem to indicate that black marlin were
not in the process of spawning off northern Peru during the period of
operation of the expedition. The females were considerably heavier (aver-
age 783 pounds) than the single male (445 pounds).

The sex ratio found in black marlin from Cabo Blanco and the apparent
much larger size of the females suggest that the latter might not occur in
company with the males except during the as yet unknown spawning sea-
son. In this connection, it is interesting to note that three specimens ex-
amined in Panama during July 14-16, 1953, ranged in weight from 200
to 366 pounds and were all males. In addition, interviews with local com-
mercial fishermen and anglers familiar with the area, reveal that black
marlin are much more abundant in the Cabo Blanco area during June
through November, and very scarce or absent the rest of the year. The
simultaneous occurrence of mostly females in Peru and mostly males in
Panama during July is suggestive.

Whether or not the black marlin occurring in Peru form part of the same
race or population as those occurring in more northern waters has not as
yet been established. It is hoped that the biometric data obtained in Cabo
Blanco may help in the solution of this problem. In addition, the oceano-
graphic data obtained correlated with the occurrence of the fish in Peru-
vian waters and nearby areas, is expected to throw light on their migratory
movements.

Examination of the stomach contents of the black marlin studied
revealed a wide variety of food. Jack crevalle (Caran.x hippos) were found
in 7 stomachs and was the fish most frequently occurring in the stomach
contents. Sometimes the stomachs would contain only this species and as
many as 4 large jacks would be found in a single stomach. It is interesting
to note that the occurrence of jack crevalle in Cabo Blanco waters was

22 •

spasmodic and that the degree of abundance of the species in the commer-
cial catch in the area, appeared to be correlated with the abundance of
black marlin. Small sharks and manta rays (unidentified) were found to
occur in 4 stomachs. Black skipjack {Euthynnus lincatus), yellowfm tuna
(Thunnus albacares) and sierra mackerel (Scomberomorus sierra) were
found in 4 stomachs. Bonito {Sarda chilensis) and cojinova {Neptomenus
crassKs) were found in 2 stomachs. Squid were found in only one stomach.
Two stomachs were found to be empty and 3 were "thrown" by the fish
during the fight. Seven stomachs were not examined.

The only other specimen of black marlin studied during the expedition
was a female 552 pounds in weight and 2860 mm. in length, captured off
La Plata Island, Ecuador, on October 3. The ovarian condition of this
specimen was similar to those observed in the Cabo Blanco area and dis-
cussed above.

FiGURh 9. House utilized as headquarters by the expedition at Salango, during
the period of work off the coast of Ecuador.

Only one sailfish was studied during the expedition. This specimen, a
female 2370 in length (weight not taken), was captured off La Plata Island,
Ecuador, on September 2 1 . The ovaries were found to be in a resting
condition not near the ripe or recently spent stage.

As already indicated, no sailfish were seen in Chile or Peru during the
expedition. Interviews with commercial fishermen in Chile indicate that
this species does not occur in that area. A number of specimens, however,
have been taken in the Cabo Blanco area by anglers and commercial fish-
ermen during the summer and indications are that the species is much more
abundant there during that time of the year.

Of the 1 1 specimens of broadbill swordfish landed in northern Chile, 10

'23

were measured and dissected. Vertebrae were obtained for age studies and
to gonads and stomach contents analyzed. A small specimen 1960 mm. in
fork length was skeletonized and brought back to the laboratory for osteo-
logical study. These specimens ranged from 231 to 772 pounds in weight
(average 523 pounds) and 1960 to 2820 in fork length (measured from
tip of lower jaw). All of 9 specimens sexed were females. The ovaries
appeared to be in a resting condition, not nearly ripe or recently spent,
thus indicating that spawning was not taking place in the area during the
period of work of the expedition. The biometric data obtained will help
determine whether the swordfish occurring off the coast of Chile forms
part of the same race or population as those in more northern waters or
represents an independent unit.

Although only 4 swordfish were sighted (none taken) during the angling
operations off Cabo Blanco (July 24 through September 10) interviews
with commercial fishermen and technologists of various fishing companies
revealed that swordfish should have been much more abundant during
July through October. In fact many commercial fishermen and fishing
companies located in the vicinity of Cabo Blanco (Mancora) derive their
livelihood almost entirely from swordfishing. A study of the statistics on
monthly swordfish production in the area comprising the years August,
1948, through May, 1954, shows that the period of greater abundance
has occurred during August through October with a peak in September.
The expected run for the area in 1954 had not materialized when the
expedition left in the middle of September. The statistics also show another
period of abundance, to a lesser degree, during March. The periods of least
abundance appear to occur during May through July with a peak in June,
and during November through January, with a peak in December. Sword-
fish are present in northern Peruvian waters the year round but the statis-
tics do not show the prevailing sizes of fish during the periods of greater
and lesser abundance.

Statistics on swordfish production issued by the Chilean government for
about the same period (1948-1952) as those covered by Peru, indicate a
well marked period of abundance during May and June and a well marked
period of least abundance during November through February with a peak
in December and January. As further confirmative evidence, it is interesting
to note that swordfish were very abundant off northern Chile during May
and June, 1954, and that abundance decreased towards July. During the
expedition angling operations in Chilean waters, 29 individuals were
sighted during the period comprising June 1 through June 17, whereas
only 18 individuals were sighted during the period comprising June 18
through July 6. On June 1, 9 broadbill were sighted in 1 hour and 15
minutes, between 1245 and 1400. A number of anglers operating out of

24 '

Iquique during the week of August 1 through the 8th, were unable to sight
any swordfish.

Comparison of Chilean and Peruvian statistics show that the period of
greatest abundance (May, June) in northern Chile corresponds with the
period of least abundance in northern Peru, and that as abundance
decreases in Chile from late June on, it increases at the same time in north-
ern Peru, reaching its peak in September. On the other hand, the period of
least abundance in northern Chile (November through February) also
corresponds with another period of least abundance for northern Peru.

It may be tentatively inferred from the above that perhaps the
Chilean and Peruvian swordfish may belong to the same population and
that they may move towards the north, from Chile to Peru, during late
June through September. It may be pointed out here, that commercial
fishermen operating in northern Chile state that the schools of swordfish
move from south to north (Tocopilla towards Iquique and Arica) during
late June and July and that the commercial fishermen operating out of
Mancora, northern Peru, have known for years that the September run
comes from the south. The fish arrive first ofl" Paita, about 65 miles south
of Mancora and a few days later they show up off the latter locality. The
coincidence of periods of least abundance for Chile and Peru during No-
vember through February may mean that the fish have moved into as yet
unknown spawning grounds during that time before returning south. This
period (November through February) comprises late spring and early sum-
mer in the southern hemisphere and it is interesting to note that Atlantic
swordfish spawn during that season of the year in the northern hemisphere.
.As already indicated, the gonads of the swordfish examined in northern
Chile during April through July, and in northern Peru during August, ap-
peared to be in a resting condition, thus indicating that spawning must take
place sometime between September and April.

In addition to billfishes, yellowfin tuna, bonito, mackerel, and other
sconibrid fishes were studied in northern Chile, Peru and Ecuador.

0Pther iiitfiaqU'al Ohserrations

During the period of work in Chilean waters, arrangements were made
to cooperate with Dr. Francis O. Schmitt, head of the Department of Bi-
ology, Massachusetts Institute of Technology, in connection with studies
of the giant nerve fibers of the squid (Figure 6). These are among the
largest single nerve fibers in the animal kingdom and are being used in the
above institution in the investigation of the chemistry of the squid nerve
axoplasm.

Since the giant squid (Figure 3) occurring in the Humboldt current ofT
Chile were expected to possess even larger nerve fibers, the expedition

'25

undertook to collect and dissect specimens in order to obtain material for
study. Two specimens were collected and the dissected material sent to
Massachusetts.

Observations on whales, incidental to the billfish work, were conducted
on several occasions. The only species positively identified was the sperm
whale which appeared to be rather abundant off Chilean waters.

C O M ^I E II C; I A 1. F I !^ II E K Y S IJ R V E Y

General

Acknowledgement is gratefully accorded to the various government agencies
and commercial fishery operators for the data and statistics on commercial
fisheries which have been used in compiling this report.

THE MAJOR SEA fisheries from Chile to Panama are for the tunas, which
are found during every month of the year. Billfishes are also caught
in some quantity and swordfish account for nearly 80% of the billfish catch
in the area from northern Chile to southern Ecuador. This area now ranks
third in the world's production of billfish, after Japan and its mandated
islands, and the northwestern Atlantic from Cuba to Nova Scotia.

In northern Chile the billfishery has provided fish for local consumption
for over half a century but no serious attempt has been made to export
outside of minor quantities to a few neighboring countries and a small
amount picked up at sea by an occasional refrigerator ship from the United
States.

In Peru, commercial swordfishing started in the last years of World War
II when the loss of the Japanese supply encouraged American fishing in-
terests to search for new sources. American tuna vessels had reported large
schools of swordfish off the northwestern coast of Peru for many years, and
the first organized fishery was established at Mancora and Paita soon after
the end of the war. No local industry had ever been built up, as in Chile,
because the native fishermen have a superstition against eating the flesh
of swordfish.

The Wilbur-Ellis Company of San Francisco has pioneered the Peruvian
swordfishing, along with their tuna operation, and have been very success-
ful. Modern harpooning methods and equipment are used and their rate of
catch per man-boat for the number of fish seen is vastly higher than in
Chile, where an older method is used.

The entire swordfish catch of Peru is exported, principally to the United
States, either unprocessed or as steaks and fillets, by refrigerated vessels.
A fair amount of black and striped marlin are harpooned each year, along

26 •

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27

with swordfish, in the area from Paita to Mancora. It is impossible to es-
timate the quantity since the fish are cut up on the beach and consumed
locally. Due to the great demand for fish locally, all types of surface sharks
are also harpooned.

The expedition introduced the first experimental work ever attempted on
the west coast of South America in the use of the Japanese long or flag
line fishing gear. Due to shipping delays of necessary equipment, it was
impossible to start this experimentation in Chile. It was not until the es-
tablishment of the base at Talara and with the cooperation of the Wilbur-
Ellis Company, that the first sets were made. This company very kindly
conducted all the organization and operation of the expedition's equipment
under the able direction of Mr. Donald Bates, Jr., their fisheries research
expert. The results so far have exceeded all expectations as will be shown
in the section under Peru.

From Peru northward across the Gulf of Guayaquil and along the Ecu-
adorian coast, commercial billfishing rapidly diminishes. A few swordfish
are reported from twenty to sixty miles ofi" the Salinas area during Sep-
tember and October and occasionally in February and March but appar-
ently the large schools that touch the coast a few hundred miles south in
the Mancora to Paita section, swing far offshore here, if they do migrate
this far north at all.

The only commercial fishery in Ecuador is out of the Port of Manta.
This town is unique in that it is the only area of the world, as far as is
known, where the principal fishing operation is for black marlin. These
fish are caught in substantial numbers during the months of June through
October and in smaller quantities during other months, from Manta south-
westward to La Plata Island. Along with the black marlin some Pacific
silver or blue marlin, striped marlin and a few sailfish are caught. They
are shipped in the frozen state, principally to Puerto Rico. Marlin fishing
is done on the relatively shallow coastal shelf, but it is possible that they
might also occur farther ofl'shore.

Chile

The expedition's observations in Chile covered a period of three months,
from April 22, to July 14, 1954. During that time the base was main-
tained at Iquique, the largest commercial fishing port in northern Chile
(Figure 10) . About 80% of the entire Chilean swordfish catch is landed here.
The city also has the largest tuna canneries in South America and leads
the country in total capital invested in fisheries. While the entire field
operation of the expedition was devoted to the study of Zone I (Iquique)
some data were compiled concerning Zone II (Antofagasta) and Zone III
(Coquimbo). This information was very generously provided by the gov-
ernment and the local companies. (Sec Tables 1-4).

28 '

Table 1
Number of People Employed in the Chile Fishing Industry-1952

Number of Crews on

Fishermen Cannery Vessels

Employees
in Canneries

Total

Iquique

Antofagasta

Coquimbo

823

467

538

113

711

—

2,072

580

652
340

127

1,119

1,942
991

838

3,771

Number of Fishermen in Various Zones and % of Chile's Total-

1943; 1951; 1952

1943 — %

1951 — %

1952

%

Iquique

239

4.3

780

10.7

823

10.7

Antofagasta

294

5.3

492

6.8

538

7.8

Coquimbo

604

Il.O

678

9.3

711

9.1

Number of Fishing Vessels and Boats Used in Various Zones
Studied, 1951 - 1952

Under 10 Tons
Over 10 Tons (Motor Vessels)
1951 - 1952 1951 - 1952

Average 4 Tons

(Row Boats)*

1951 - 1952

Total
1951 - 195:

Iquique

Antofagasta

Coquimbo

17 20

4 4
1 4

202

100

71

170
1 1 0

73

240 203
212 203

268 277

461 393

316 317
340 354

22 28

273 353

720 683 1,117 1,064

*Note: Row boats and skiffs average less than 1 ton

Zone I — Iquique. This Zone is in the State of Tarapaca and includes
the ports of Arica, Pisagua, Iquique and Cavancha. Arica, on the border
of Peru and Chile, has a local swordfishing fleet of about twenty-five boats.
The number of vessels is not constant in any one port since the boats shift
from port to port, following the schools of fish. Arica has a small cannery
and freezing plant. The cannery processes anchovies, sardines and bonito
(Figures 12, 13). Most of the swordfish are frozen and exported to La Paz,
Bolivia, by rail.

Southward, Pisagua is a shelter used by the fleets of Arica and Iquique
when the fish are in that vicinity. Iquique, one hundred and twenty miles
south of Arica, is the principal fishing port of the Zone. The main sword-
fishing fleet of Chile, roughly about one hundred boats, is based here, as
are the principal tuna canneries. The latter are three in number and include
large freezing capacity. One, Pesquera, Iquique, is the largest in South

• 29

America. In the southern end of the Zone there is a sheltered harbor at Pt
Lobos which is used when the fish are coming from the south. Zone I in-
cludes about 250 miles of coast line.

Table 2

Comparative Production of Fish in Chile

(By Species)

1945 X 1956 X 1947 x 1948 x 1949 x 1950 x 1951 x 1952*

Anchovies 253 416 273 927 689 570 436 427,680

Tuna 2069 918 479 274 454 412 570 773,658

Bonito 592 409 1679 2426 4250 2927 3973 4,886,415

Swordfish 1455 2166 1701 1209 690 786 870 570,113

Sardines

2872

3346 3259 1211 7397 14261

7588 4,436,757

(By Zones)

1952

I n

Iquique Antofagasta

III

Coquimbo

Anchovies

Tuna

Bonito

Swordfish

Sardines

95,400

139,600

4,499,050

481,800

348,100

31,635
925

387,365

44,590

1,894,710

21,750
6,948

43,723
12,430

1951

Anchovies

Tuna

Bonito

Swordfish

Sardines

289,600
151,900
3,510,100
560,250
134,400

71,560

461,300

244,140

1,752,135

32,625
3,684
1,558

65,734
8,000

X in Ions
* in kilos

Zone II — Antofagasta. This Zone includes the entire State of Antofa-
gasta and the ports of Tocopilla, Mezillones, Antofagasta and Taltal. Toco-
pilla, at the north end of the Zone, is the main swordfishing area. There the
fleet comprises from thirty to thirty-five boats. These at times overlap with
the Iquique fleet, depending on where the main body of fish lie and which
port is paying the higher price. Next to the south is Mejillones, situated on
a long headland north of Antofagasta which port is too far southeastward
in a deep bay to be able to reach swordfish grounds. The last port south
in the Zone is Taltal. Because it is rather remote not much information is
available. About a dozen boats fish swordfish, plus, probably, a few more

30 '

from the smaller villages adjacent to it. It is well to note that in all Zones,
every little village has a few craft available for harpooning when the fish
are in the vicinity. The fish are consumed locally and since no government
inspectors are available it is impossible to estimate the catch accurately.
For this reason no catch figure is included for this area in the totals in the
table. Zone II ranks second in swordfish production. Its coast line is about
250 miles long.

Zone III — Coquimbo. The States of Atacama and Coquimbo comprise
this Zone. It is the longest of the three, being about 400 miles in extent.

Table 3
Cannery Production in Chile, Zone I-

1951

Companies and Products

Raw Material Total

Finished

! Prod. Total

Pesquera Iquique S.A.

El Colorado — Iquique

Tuna in Oil

20,399

9,233

Tuna Natural

20,413

8,463

Bonito in Oil I

.598,611

636,657

Bonito Natural

473,678

197,678

Shark — Dried

24,511

5,802

Industrial Oil

3,221

Fish Meal

2,137,612

1,015,988

Sociedad Ind. Pesquera

De Tarapach Ltda. — Cavancha

Anchovies in Oil

58,590

17,597

Anchovies Natural

1,760

137

Anchovies in Tomato

87,355

36,023

Tuna in Oil

49,079

14,597

Tuna Natural

32,045

9,234

Bonito in Oil

454,378

120,040

Bonito Natural

593,709

151,512

Swordfish in Oil

1,420

148

Swordfish Fillets

1,124

557

Sardines in Oil

11,418

3,115

Sardines in Tomato

3,092

920

Shark — Dried

39,666

10,415

Fish Meal

1,333,636

227,022

591,317

Sociedad Pesquera Ind.

Ltda. Pacifico — Iquique

343,686

102,853**

Jorge Cerda "Buen Gusto"

Arica

579,306

202,516**

* in kilos

** (No Swordfish)

31

Table 4
Cannery Production in Chile — Zones II & 111-

-195r

Companies and Products

Raw Material Total

Finished Prod. Total

II Zone: Antofagasta

Compania Ind. Pesq. De

Antofagasta — Cipa

Bonito in Oil

2,800

Bonito Natural

300

Sardines in Oil

453,455

Sardines Natural

96,930

Sardines in Tomato

6,475

Fish Meal

240,170

Mateo Zlatar O.

-El Cobre"— Caleta

Anchovies in Oil

11,760

Bonito in Oil

42,390

Bonito Natural

63,505

Bonito Meal

9,340

Sardines in Oil

118,015

Sardines Natural

357,632

Sardines in Tomato

145,850

Fish Meal

89,073

III Zone: Coquimbo

Industrias Pesqueras

Guayacan

Anchovies in Oil

21,325

Anchovies in Tomato

11,300

Bonito Natural

1,558

Mackerel Natural

46,392

Red Snapper in Oil

16,425

Red Snapper Natural

69,461

Fish Meal

54,610

800,130

837,565

229,092

1,129

184

101,778

42,381

2,425
51,686

2,940
12,906
21,779
1,868
19,916
115,543
39,890
17,814

11,575
6,818
861
25,558
12,779
35,695
31,725

; 99,583

232,656

131,337**

* in kilos ** (No Swordfish)

No reliable reports of swordfish have been received south of Coquimbo
The two major swordfish ports are Chafiaral and Caldera. Chanaral is
probably the major producer since more boats are reported fishing from
here. About twenty to twenty-five boats fish from this port during a rela-
tively short season. A short distance to the south is Caldera, apparently
the next best producer in this Zone. No figure is available on the number
of boats, but it probably is about that of Chanaral. A few fish are reported
taken from Coquimbo north, and this area is assumed to be the southern

32 '

boundary of the swordfish migration on the coast of Chile.

Fishing Methods and Procedures. Swordfishing in Chile is a primi-
tive operation. The harpoon is used and aside from slightly larger boats
and improvements in the motors used, there has been no material advance
in the last twenty-five years. This can be attributed to a lack of organized
fishing and adequate financing. Generally, northern Chile can be consid-
ered virgin territory for the development of modern techniques in this type
of fishing.

Boats. The craft used in swordfishing are of one general pattern. They
are of a double-ended sea-skiff design, from 22 to 28 feet in length. They
were formerly powered by oar and sail. However, by the mid-twenties con-
version to power had started. By 1940, the entire fleet was motorized. Due
to the Import Tax and to the cost of motors the boats are vastly under-
powered. The motors are of British or German design and manufacture.
The average horsepower is about 20-30 with a very few as high as 60 H.P.
The boats are of heavy hard-wood construction and the average cruising
speed of the fleet is 5 knots, with a top of 7 knots. The boat design is a
completely open cockpit and flush deck, divided into four to six sections
for storage of gear, fish and a shelter for the crew. The freeboard, at bow
and stern, is about three and one-half to four feet, with roughly two feet
midships. The use of a pulpit for harpooning has never been tried in Chile,
primarily due to lack of example, plus the small size and slow speed of
the craft. In general it is apparent that any future expansion in this field
will require a complete redesign of the present type of boat, coupled with
the necessary increase in power. This can be achieved in Chile only by
the active support of the commercial companies. It would be financially
impossible for an individual crew or group of crews to acquire the desired
equipment.

Fishing Equipment. The gear employed in the commercial harpooning
of the billfishes is as obsolete and inefficient as the boats, because of the
lack of organized backing to fishing, and because each boat and its crew
operates as an independent unit, living a hand to mouth existence. Fisher-
men have never had commercial or government encouragement in devel-
oping efficient equipment.

The cost of good gear is beyond fishermen's means. Instead of longline
manila or cotton rope for their harpoon lines they manufacture their line
themselves, from any old marine rope. This is destranded, blended with
raw, long manila fiber. The final result is a line of low tensile strength. A
rough 1/4" native line will break at about 175 to 225 pounds in comparison
with a 450 pound test of machine made cotton. Many large and active fish
are lost because of this.

The harpoons or darts used are of the conventional American design and

• 33

JFMAMJJASON
Figure 11. Production of swordfish in northern Chile by zones, during
1948-1952. Monthly averages.

are manufactured locally. The metal used is copper or raw iron, and the
dart is shorter and has less surface area than the American model. Also,
there is less angle at the tail flanges. The chance of pulHng or ripping the
dart out is thus increased.

Darts are connected to the line by 3 to 5 feet of cable or twisted wire.
Some fishermen use a 1/8 to 5 '32 nylon or dacron connection, which has
less tendency to tear the flesh of the fish than metal. No key or barrel is
connected with the line to restrict the movements of the fish after it is har-
pooned. The standard Chilean procedure today is to handplay the fish.
Should all available line be taken out with a strong fish any buoyant ma-
terial in the vessel is tied on with the hope that the fisherman can follow
gear and fish.

34 '

Harpoon poles are of a heavy wood, 2" to IVz" dia., length 10' to 12'.
They are short and heavy because of the low freeboard of the boat and its
lack of pulpit necessitating the striker throwing in a high arc to reach the
fish before it sinks.

From a study of billfish production in Chile, it appears that the accepted
concept that the swordtish migration to this part of the continent come
from the South, touching Chile about at its mid-point (roughly the Co-
quimbo area) and progressing northward with the flow of the Humboldt or
Peru Current, is substantially correct. The figure (Figure 11) showing
monthly average production from 1948 to 1952 supports this. Zone III,

60 1

I > >

JFM AM JJASOND

Figure 12. Production of tuna and bonito in northern Chile by zones,
during 1948-1952. Monthly averages.

' 3S

80

60
T
0
N UO «

s

20 <

I Q U I Q U E

kOOi

JPHAMJJ AS ON

Figure 13. Production of sardines in northern Chile by zones,
during 1948-1952. Monthly averages.

Coquimbo, shows the major production of the year. It also shows the least,
but in all probability, if the same number of boats operated here as in the
Iquique area, the catch would be more than doubled.

As the schools flow northward or slant in from the ocean, there is in-
creased production in the Antofagasta Zone, and its peak is about two
months later than Coquimbo. Again the number of boats and fishermen
involved is far less than Iquique. The fish here seem to swim farther off-
shore; due to oceanographical features, the clear blue water does not come
in as close as in the Iquique Zone and it is in this water that the bulk of
the fish are found. In Zone I (Iquique) heavy production occurs for the
longest period of the year, the majority of the fleet operating from four to
five months.

At Arica, the coastal shelf of Peru is encountered and the fish swing out
to sea. No production is found in central and southern Peru. While it is
evident in all three zones that swordfish do travel from south to north, it
seems possible that additional fish are constantly arriving from the outer
ocean, especially in Zone I (and due to warmer water and better feeding
conditions, hold closer to the coast for longer periods).

36 '

The extent of the marUn migration is far more Hmited than that of
swordfish. Their range is throughout Zone I and somewhat south of Anto-
fagasta in Zone II. None are reported in the northern part of Zone III. The
duration of their stay is quite short, roughly the months of March, April,
May and early June. However, in some years a few marlin are in evidence
as early as February in the Tocopilla-Iquique area. They are practically
non-existent in these waters after July 1. It is assumed that they proceed
from south to north, following the current. The marlin range much closer
to shore than the swordfish, preferring the belt of green water inside the
clear blue. The expedition also discovered that they seem to occur in great-
est numbers in the areas of warmer water, and feed more actually here. In
some years the catch of marlin may be as much as a third that of the
swordfish, but the average is about 20 /( . The selling price is 40 to 45%
that of swordfish.

One hydrographic feature of Chile must be remembered in considering
the fisheries. There is no continental shelf, since the coastal range of the
Andes enters the sea at a steep angle, and from the border of Peru south-
ward for nearly 600 miles the 100 fathom curve will be found about one-
half to three miles offshore. In this stretch, uninterrupted by banks or is-
lands, it is natural to assume that the swordfish and marlins will follow a
pattern of temperature, salinity and food conditions most suitable to their
needs.

Peru

General. This expedition, during its two and a half months operation
in the waters of Peru, was based at Talara (Figure 10), which is the princi-
pal refining and oil shipping port of that country.

This area was chosen for the study of billfish in Peruvian waters because
it is the heart of that type of commercial fishing and the black marlin
caught here are the average largest in size found in any part of the world.
Both the black and the striped marlin occur here every month of the year,
and the area has also two distinct runs of swordfish, in the summer and the
winter seasons.

Since 1947 several seafood companies have been established at Man-
cora on the north of Talara, and at Paita on the south. These enterprises
are primarily devoted to the catching of swordfish and tuna. This industry
has flourished rapidly in recent years. It appears now with the tremendous
demand for fish sticks and fillets in the United States that it may be com-
mercially profitable to develop bottom fishing on a large scale. Both Man-
cora and Paita have very modern refrigeration and packing plants. The
leading company is the Wilbur-Ellis Corporation of San Francisco, which
initiated the first commercial swordfishing operation in 1947, and has stead-
ily expanded ever since.

• 37

There are two separate runs of swordfish in these waters, one which
arrives in the summer season just after the first of the year and remains
until the end of March, and the second which appears the end of August
and remains until the end of October. The entire catch of these fish is ex-
ported by the American Company in Manta to the United States.

It is interesting to note that swordfish have been reported in these waters
for many years, yet no commercial fishing for them was practiced until the
Wilbur-Ellis enterprise was started, owing to a native superstition. While
the marlin and sharks are in constant demand, the native, even today, is
very reluctant to eat swordfish.

This section of Peru is the only area of commercial swordfishing. Farther
south, through central and southern Peru, an extensive coastal shelf is en-
countered, and consequently the fish are beyond the reach of the small type
of boats employed. Along with the deep water and the strong ocean cur-
rent found here, an added inducement for swordfish is a series of banks
northwest of Ancora. These banks have a high concentration of bottom
fish, which is the favorite food of the swordfish.

The population of fish in the two schools that migrate to this area are
far more extensive and concentrated than any found ofl" the coast of Chile.
Here, a marked decrease was noted in the size of the fish. The average
Chilean swordfish weighs slightly in excess of 500 pounds, while the Peru-
vian fish will run above a 350 pound average. This difference in size be-
tween two areas more than 1,000 miles apart, may possibly indicate the
entirely separate populations of fish.

The yearly production in this relatively small area of Peru is nearly as
great as that of the entire three zones of Chile previously described; in fact,
there were good years when it actually exceeded the production of Chile.
All available production figures for swordfish and tuna are given in Table
5. Along with the swordfish there is a large population of black and striped
marlin. Also a few sailfish are seen in the summer months.

The black marlin caught here are by far the largest found in any part
of the world. Since the start of sport fishing at Cabo Blanco and the fairly
extensive harpooning of the black marlin by the sword fishermen, the av-
erage weight has been close to 800 pounds. During 1954, the fish were
exceptionally large and the average went up to 850 pounds. It is not
known why these fish should be so large here in comparison with other
black marlin populations in Australia, New Zealand, Ecuador and the
Gulf of Panama. It also seems odd that a small fish in the vicinity of 400
pounds is rarely seen here. All the world's records of black marlin fish
recorded in the past five years have been caught at Cabo Blanco. The
present record is 1560 pounds and it seems possible that the maximum size
may be in excess of 2,000 pounds. There have been some extremely large

38 •

fish harpooned but, unfortunately, they were never weighed before being
dressed.

The black marlin, while present every month of the year, seem to pre-
dominate in the winter season, during the months from June through Oc-
tober. This is the windiest season of the year, having an average daily
velocity of 20 knots. Its prevailing direction is from south to southwest.
This course of the wind holds generally from northern Chile through
southern Ecuador. The black marlin seem to prefer to surface, traveling
with the wind when the weather is the roughest. In the calm summer
months, or on any relatively calm day few fish are seen on the surface. It
is interesting to note that this is the only part of the world where this fish
is seen on the surface in any great numbers.

The striped marlin off northern Peru are much smaller than those off
Chile. The average is not more than 150 to 160 pounds. They appear in
the greatest numbers during the late summer; the months of February,
March and April appear to be the height of their season. During this pe-
riod there are also a few sailfish in the Cabo Blanco to Mancora area. This
point is probably the southern-most limit of the sailfish migration from the
north. As far as could be ascertained, there is no concrete evidence of the
so-called Pacific silver marlin being caught here, though the fish do occur
a relatively short distance north ofl" southern Ecuador. The entire catch of
these fish is exported, according to the records provided by the Wilbur-
Ellis Company.

The principal commercial fish of Peru are the tuna and the bonito. The
greatest concentration of the yellowfin tuna is in the vicinity of Mancora
and the adjacent banks on the northwest. Farther south, from Paita to
central Peru, is the main range of the bonito, both the common and the
oceanic varieties being caught in quantity.

The main bulk fish canned in Peru are the two varieties of bonito. This
production of canned fish is done by six domestic and two foreign com-
panies, both of which are American controlled and operated. Their yearly
production by the month is illustrated in the government Fisheries Reports
appended to this section on Peru.

Geography. The area studied encompasses the northwest section of the
coast line of Peru (Figure 10). This area is the most westerly point of the
South American continent. It is bounded on the north by the Gulf of Guay-
aquil, the center of which is 3° south of the equator and extends to the
vicinity of Paita, 6° south. The principal commercial fishing ports are at
Mancora at the north end of the area and Paita on the south. The distance
separating these two points is only about ninety miles, but generally speak-
ing, they have opposite seasons and different fishing conditions in relation
to the production of swordfish. This is due, to a great extent, to the sep-

• 39

arate and rather unrelated geographical features. Paita on the south is still
affected by the Humboldt current sweeping up from Chile. For reasons not
ascertained this produces an early school of swordfish in the months of
February, March and April. When the southerly inshore Niiio current is
fairly strong here, these fish penetrate it in quantity and are caught rela-
tively close to the coast line. As there are no settlements or villages of any
importance south of Paita, nothing is known concerning the first contact of
this particular group of fish with the continental shelf. The 100 fathom
curve from Talara, which is the center of the area, is distant from five to
thirty miles offshore, increasing in distance in going southward from Ta-
lara. During the run of swordfish in the southern part of the area, very few
are caught in the vicinity of Mancora. This port, at the southern end of
the Port of Guayadjuil, has its peak production from a second school of
fish in the months of August, September and October. At the same time
the production in the vicinity of Paita is light. Why two adjacent ports
should have such different periods of productivity, is a mystery still to be
solved.

It is the general supposition that the early season school of fish in the
vicinity of Paita arrives from a southwesterly direction, similar to the
movement of fish off northern Chile. At the height of production off Man-
cora the swordfish seemed to drift towards the coast from a westerly or
northwesterly direction, first arriving on the banks between Mancora and
Zorritos about thirty miles to the north. These banks, as before mentioned,
are from 25 to 40 miles offshore. The average size of the fish, in both
cases, seems to be about the same, though the Wilbur-Ellis Company re-
ports that there are more very small fish produced in the Paita area. These
little fish run as low as 25 or 30 pounds in weight and there are many
caught weighing about 60 to 80 pounds. This, apparently, is the only point
on the west coast of South America where the small swordfish are in evi-
dence. Southward from Paita there are reports of swordfish from American
tuna clippers and Grace Line freighters. These fish are seen from 40 to
100 miles offshore and generally from the months of April through Octo-
ber. In the northern end of the area, from Zorritos across the Gulf of Guay-
aquil to Salinas, Ecuador, there is very little recorded about the fish. While
a few have been taken from 40 to 60 miles offshore in the vicinity of
Salinas, it would seem logical to assume that the vast majoriy of fish in
the Mancora area retreat to the westward and toward the range of com-
mercial fishing observation.

The migration of marlin to these waters, both the black and the striped,
is as complex as that of the swordfish. The striped marlin have an early
year run, roughly from January through May. Their greatest concentration
is from Talara to Mancora with a fair scattering of fish extending south-

40 '

ward to the vicinity of Paita. There are occasional fish caught every month
of the year but they are most plentiful in this particular period of time,
which is the summer season and the calmest period of the year. The great-
est predominance of black marlin is in the winter season and also the
roughest. Why these two species should be so different in their seasonal
occurrence along this coast is not known. Food conditions are excellent in
any season of the year, so apparently this has little or no bearing on the
question.

Fishing Methods. The commercial production of billfish off the coast
of Peru is solely through harpooning. Due to American training and equip-
ment since the war, fishing methods are the best encountered along the
west coast of South America. Before the war there was little, if any, sword-
fishing, and the fishermen concerned themselves with casual harpooning of
marlin and sharks in the course of their general bottom fishing operations.

While the fishermen have not been harpooners by nature, they have
developed skill rapidly in the past seven or eight years through the oper-
ations of the Wilbur-Ellis Company. The primitive methods encountered
off northern Chile have never been used here and consequently the fisher-
men have readily adopted modern techniques.

The average size of craft employed is from 25 to 30 feet in length. It is
equipped with a conventional harpooning pulpit or plank of about 8 to
12 feet in length. The length of the plank is restricted because of the rough
water encountered in the winter season. These boats are powered with two
or four cylinder engines and have relatively low horsepower. They do not
have the required speed for full efficiency, but are fairly adequate. All the
gear and equipment relative to harpooning is of local manufacture but of
American design, the only exception being that most of the line is im-
ported. This reduces considerably the number of fish broken off, in com-
parison with Chile.

Methods of approaching the swordfish are strictly conventional and dif-
fer from those employed in Chile. The fish is approached from the rear,
and the vessel is kept on the outside of the fish if it shows a tendency to
circle. The only apparent weakness observed in this operation is that the
harpooners show a tendency to throw the pole a little prematurely instead
of waiting an extra few seconds until they are in effective striking range.
The fishermen are rather light and small in stature, but seem to prefer a
very long, heavy, wooden harpoon pole. Probably their efficiency could be
much improved if they were provided with one of hollow metal construc-
tion. They show a strong inclination to start hand lining the fish from the
vessel as soon as he has been struck, instead of allowing it to tow a float
with a flag attached until it is tired. This wastes a sizeable amount of the

• 41

vessel's time which is obhged to deal with individual fish rather than having
several harpooned at the same time during a good day in the peak of the
season.

The fishermen harpoon anything that shows on the surface. Conse-
quently, a considerable amount of black and striped marlin, and sailfish
are killed. Along with all types of sharks they are much in demand for
local consumption. There is no export of the marlin such as that encount-
ered in Ecuador, due to the lack of sufficient quantity. A small amount of
all types of billfish are killed by the fleets of sailing craft operating from the
various ports in the production of bottom fish. They all carry harpooning
equipment and sailing back and forth from their fishing grounds have an
opportunity occasionally to strike a fish on the surface. There was no evi-
dence of attempts at drift fishing for the billfish, as practiced off Cuba. Oc-
casionally the hand line fishermen on their balsa rafts, or from their small
sailing craft, hook a swordfish or a marlin, but due to the light line used
these fishes are almost always lost. In some seasons of the year, especially
in the months of February, March and April, numbers of big-eye and
larger sized yellowfin tuna are hooked by the drifting fishermen. A few are
caught but the result is about the same as that with the billfish.

The Wilbur-Ellis Company has shown the possibility of producing mar-
kets for white meat fish, fillets and fish sticks. This is just approaching the
commercial production stage. Production of a large volume of bottom fish
would seem doubtful, due to the lack of a coastal shelf.

Table 5

Exports of Frozen Fish from Peru

In Net Tons

1948 1949 1950 1951

TUNA*

Ilo 127

Mancora 533 1248

Paita 279 897 2808 5044

Talara 10 320 3172 311

SWORDFISH

Mancora 386

Paita 274 200 446 1035

Talara 140 1114 1652 86

TOTAL

703

2531

8997

7851

SOLES

898,200

6,956,800

22,761,800

17,348,900

U. S. $

44,910

347,840

1,138,090

867,180

* All exported to U.S.A. except for 10.3 tons of tuna to Italy in 1950.

42 '

From the Port of Talara to Cabo Blanco, a section of the coast line
controlled by the International Petroleum Company and the Lobitos Oil
Company, there is a serious shortage of food. Both companies subsidize
the local fishermen, providing them with living quarters and other neces-
sities of life. This is done at a considerable cost, without any attempt to
train the fishermen or provide them with modern equipment. The entire
operation of the fishing fleet from these various ports is by sail. It is ob-
vious that much can be done to improve the production and the efficiency
in this section.

The expedition unfortunately did not have enough time, or the oppor-
tunity, to examine fully the commercial tuna industry of the country. The
results of the Wilbur-Ellis Company operation, both of swordfish and tuna
are in the appended figures.

Experimental Longline Operations. Longlining operations were
conducted by the expedition from the Port of Mancora, aboard the motor
vessel Corsario, owned by the Wilbur-Ellis Company. The longline was
constructed and operated under the supervision of Mr. Donald Bates, Jr.,
fishery technologist for the Company (Figure 5). The following informa-
tion has been prepared from periodic progress reports sent by Mr. Bates.

The gear employed consisted of 8 baskets of Italian hemp Une, 3/8''
in diameter. Oxygen tanks of 2100 cubic inches of capacity were used as
floats, 5 64" wire was used for leaders, and size 8/0 Japanese tuna hooks.
Each basket comprised 6 hooks with 7 on the end basket making a total
of 49 hooks fished. Drop lines were standardized at 8 fathoms, including
one fathom of leader wire. The mainline was made up of 20 fathom sec-
tions, with a total of 100 fathoms to each basket.

Since the Italian hemp line is soft lay, setting and retrieving times were
somewhat slow, averaging one-half hour and one hour respectively. Fur-
thermore, the vessel's winch slowed the retrieving operations because of
the direct drive from the main engine. By allowing the Corsario to drift
during favorable weather, this handicap was somewhat overcome as the
engine RPM could be increased with the drive clutch disengaged.

The gear, set downwind, floated well on all occasions, with little ten-
dency to bunch and tangle. A combination of a strong current setting to the
south with a strong wind from the southwest accounts for the baskets re-
maining in virtually the same positions. The entire gear, however, drifted
southward. In general, during the period of operations, winds were slight
during the night and early morning hours, increasing to about 35 knots
during mid-afternoon. The choppy seas would make retrieving the gear
extremely difficult for a small boat but not impossible.

One problem in introducing new fishing methods into an area is the
fishermen acceptance and adaptability in handling it. The Corsario crew

• 43

was apparently enthusiastic about fishing the longline and the men were
able to understand the procedure with only two days of direct supervision.

The bait used for the longline tests comprised sardines and mullet from
6 to 8 inches long.

The abundance of giant squid in Peruvian waters presents a problem
in connection with the feasibility of longlining in that area. Many bait^
were taken from the gear by these animals during the tests, but in general
they were not as bothersome as expected. Apparently the squid occur in
belts and in colder waters. Daily drops of a squid "test" line before setting
the gear did not prove too helpful in detecting their presence. Even though
squid might have been present as shown by the loss of baits, it was en-
couraging to note that the majority of tuna captured on the longline were
unharmed. Also, the lack of shark-eaten tuna was encouraging.

The area covered by the longlining operations (about 160 square miles)
comprised a zone between 3 and 30 miles from shore and extending from
Cabo Blanco to Zorritos, a distance of about 60 miles.

Longline fishing tests were begun on August 13 and continued through
October 15. Although the expedition left Peruvian waters about the middle
of September, longlining operations continued until the above date. A total
of 27 fishing days were devoted to the investigation and 29 sets were made.
The baits were fished at depths ranging from 20 to 110 fathoms. During
the period of operations, surface temperatures ranged from 17 to 22 de-
grees Centigrade (average 20.5° C).

A total of 80 fish were obtained from the 29 sets made corresponding
to an average of 2.75 fish per set. Since 49 hooks per set were fished, this
means that an average of 5.6 fish per 100 hooks was obtained. No catch
was obtained in 8 sets and the number of fish obtained per set ranged
from 2 to 9.

The 80 fish obtained comprised one skipjack (1.2 percent), 2 broadbill
swordfish (2.5 percent), 3 cojinova (3.7 percent), 4 big-eye tuna (5 per-
cent), 22 shark (27.5 percent) and 48 yellowfin tuna (60 percent). The
only skipjack taken weighed 6 pounds and was hooked at a depth of 30
fathoms. The 2 broadbill swordfish weighed 400 pounds each and were
hooked at depths of 30 and 50 fathoms. The 3 cojinova were all taken
on a single set and no weights or depths were reported. Two of the big-
eye tuna weighed 250 pounds each and were taken on the same set at a
depth of 70 fathoms. The other two weighed 240 and 270 pounds and were
taken on separate sets at depths of 110 and 30 fathoms respectively. The
sharks ranged in size from small to large (not weighed) and were taken
in depths ranging from 20 to 90 fathoms. Yellowfin tuna comprised more
than half of the catch and ranged in size from 10 to 70 pounds (average
23 pounds). More than half of the specimens weighed 15 pounds; only

44 '

6 weighed less, and only 2 weighed 50 pounds or more. It is interesting to
note that with one exception, all of the specimens were taken in depths
ranging from 20 to 60 fathoms and most were taken between 30 and 50
fathoms. There is no apparent correlation between size and depth of cap-
ture.

The results of the preliminary experimental longline sets indicate that
longlining for yellowfin and big-eye tuna, both important commercial spec-
ies, may be profitable in Peruvian waters. Although only two swordfish
were taken, it must be remembered that as already indicated, the expected
run for that time of year had not materialized during the period of
operations.

Economy. Peru has a commercial fishing organization far in advance
of the Chilean industry. The domestic companies are well organized, and
joined with a cooperative organization in Lima are doing an excellent job.
Foreign capital and enterprise in the commercial fishing field has been more
successful, due to the modern training and improved types of equipment
provided.

The country itself has a stable currency and strong government control
and organization. Because of the availability of fishing labor, the average
income per day is only slightly higher than that encountered in northern
Chile, roughly 15% to 20% more. The yearly average income is about a
third higher than Chile, due to more constant employment. This can be
directly attributed to a better organization of the fishing interests, both
foreign and domestic.

Peru has partial price control on ocean fish production but it is not as
rigidly controlled as in Chile.

The fishermen are about equally skillful and energetic as those of Chile.
They are kept much closer to the coastal line in their operations, due to
adverse weather encountered, and to the fact that the fish are encountered
closer to the coast because of the oceanographic features of that part of
South America.

Ei'imtlitr

General. In the short time of one month that this expedition spent in
Ecuador, operating in the vicinity of La Plata Island and Salango (Figure
10), very little opportunity was offered to study the commercial fishery. The
greater part of the information available concerned the history of the
fishery. Ecuador and its adjacent waters have been very potent in the past
as regards the tuna industry of the United States. The area is the most
southerly limit of operational tuna fleets from Southern California. It was
not until 1949 that any American enterprise became established in
Ecuador.

Since the primary purpose of this expedition was the study of billfish

• 45

in the southeastern Pacific area, it was natural that interest should be
concentrated upon them in this particular section of the coast line of
Ecuador. The area investigated by the expedition included Manta on the
north to Salinas in the south and was primarily devoted to the area
surrounding La Plata Island. This site was chosen because it is probably
the only area in the world where black marlin are caught commercially in
a well defined season. These marlin, both black and striped, have been
caught here for many years, but it was not until 1950 that they supported
a commercial operation.

As a result of research by an American seafood corporation, it was
deemed practical to establish a refrigeration plant and a cannery at Manta.
In the course of the establishment of the original operation of this enter-
prise, it was discovered that marlin in the vicinity of La Plata Island and
Manta, the adjacent part on the mainland, could be caught in profitable
commercial quantity. This situation developed primarily because of the
demand for large bulk fish in the West Indies. The operation arose from
a contract with the Ecuadorian government to collect and process the
bottomfish from the Galapagos Islands and the coastal shelf of Ecuador.
When it was determined that billfish could be caught in quantity in the
vicinity of Manta, the local fishermen were encouraged to expand their
operation and were supplied with the necessary equipment to increase
the production of this type of fish. This experiment has proven to be very
successful since its inception.

The area for commercial marlin fishing around Manta is undoubtedly
the largest in the world, and it is our opinion that the production possibili-
ties have barely been scratched, if the demand for this type of seafood
continues to exist. With training in the improved modern methods of
fishing and equipment, the catch of these billfish could be vastly increased.

This area of the southeastern Pacific is not productive of swordfish. The
Gulf of Guayaquil appears to be the northernmost limit of the swordfish
schools. Possibly due to the extensive coastal shelf and the meeting point
of the Humboldt and the south equatorial current, the schools of swordfish
may be driven far offshore in the vicinity of Ecuador. From all reports,
only a few fish are ever seen, and only in the latitude of Salinas, from 40
to 60 miles from the coast.

The principal billfish caught off the coast of Ecuador are the black
marlin, the striped marlin, the so-called silver marUn and the sailfish.

Since there are no accurate governmental records available, it is impos-
sible to estimate the yearly production of the various species. A conserv-
ative estimate of the yearly export of these fish from the port of Manta,
would be between L50 and 200 tons. Practically all of this export of fish
is picked up by refrigeration vessels and sold in Puerto Rico. It is interest-

46 •

ing to note that this area appears to be the southern-most Hmit of the
migration of the so-called silver marlin of the Pacific. While this fish is
caught in most of the tropical and subtropical areas of the Central Pacific,
its range along the western coast line of North and South America appears
to be limited to the mouth of the Gulf of Lower California on the north and
south to the area under consideration. There have been a few reportedh
caught south of the Gulf of Guayaquil in the vicinity of Mancora, Peru
but no definite records were available to substantiate this.

Black marlin were found to be predominant in about the same season
as in the northern part of Peru on the south side of the Gulf of Guayaquil.
Again, the fish appears in the greatest abundance from June through
October. The only marked difference in the fish is its size. While the
average fish caught in the Mancora area of Peru is between 700 and 800
pounds, the average fish caught off southern Ecuador run less than 500.
Also, it is interesting to note that 1,000 pound black marlin are rarely
caught in Ecuador but are fairly common 200 miles south in Peru. A small
fish in the 200 to 300 pound class is seldom seen in the Peruvian waters
studied, yet they are very common in the adjacent Ecuadorian waters.
According to the ichthyological studies conducted during the expedition,
the size of the fish appears to be correlated with sex, the females being the
larger.

The striped marlin in this vicinity of Ecuador arrive in their greatest
quantity much earlier in the year than the blacks. From the information
available, it appears that they arrive at their peak in the months of March,
April and May, which are roughly the best months for the same fish off the
northern coast of Chile. As in the case of the black marlin, there is a
reduction in the size. It appears that they weigh 120 to 140 pounds. The
few caught during the period of the expedition in these waters were very
small, averaging around 100 pounds. It is interesting to compare the three
zones in which the expedition studied the striped marlin. In northern
Chile the fish averaged very close to 300 pounds. From central to northern
Peru the average was about 180 to 200 pounds and finally they declined
to the above mentioned weights in southern Ecuador. From morphometric
standpoint these fish are similar in every respect.

A third species of marlin is recorded from this area. It is possible that
this fish may be identical with the blue marlin of the Atlantic. It is hoped
to clarify this in the near future. The fish itself is not common in this
particular part of the Pacific or any other area with the exception of the
Hawaiian Islands. This marlin may occur any month of the year off the
coast of Ecuador and on an average the few caught run considerably
larger than those recorded northward in the Gulf of Panama. During the
month the expedition was based at Salango, two specimens were observed

• 47

that had been caught commercially. One was very large, probably in excess
of 700 pounds, but unfortunately it had been dressed before it could be
carefully examined. The second was a specimen of about 350 pounds.
From the reports given by the local fishermen these fish average in weight
almost that of the black marlin.

The predominant saiMsh run here is in the summer months, roughly
from the end of November through March, although (as in the case of the
three marlin) they are caught every month of the year.

The general tuna situation is similar to that off the coast of northern
Peru. The principal species is the yellowfin tuna which is caught every
month of the year, but predominates in December, January and February.
In the winter season the fishermen have the same heavy runs of the oceanic
bonito that were encountered off Peru. The common bonito is rather
scattered, and its production does not compare with that of central and
northern Chile.

Geography. The operational site for the Ecuadorian phase of the
expedition was the village of Salango (Figure 10). This was chosen because
it was adjacent to the Island of La Plata and just southwest of the city of
Manta which is the principal commercial fishing port of Ecuador. This
area is 60 miles north of the mouth of the Gulf of Guayaquil. The city
of Salinas is at the northwestern tip of the port of Manta. The Island of
La Plata, our principal point of fishing research, lies about 18 miles off the
coast and 5 miles inside of the 100 fathom curve of the coastal shelf. From
Iquique, Chile, northward through the Peruvian areas studied, we found
that this is the first place in which a definite coastal shelf is encountered
where billfish exist in quantity during the migratory cycle. From this point
northward, it is apparent that the schools of marlin and sailfish touch all
prominent coastal points northward to the Gulf of Panama. Possibly these
fish constitute a single population, while the sailfish, to some extent, mi-
grate across the Gulf of Guayaquil and in summer season range as far
south as Talara, Peru. Generally, the main group never migrates farther
south than Salinas, Ecuador.

The expedition received only vague reports of billfish north of the port
of Manta. By the close proximity of the 100 fathom curve to the coast line
in the vicinity of Cape San Francisco, just south of the port of Esmeraldas,
it is logical to assume that similar fishing conditions would exist. There
are no governmental reports available for this area and only future explor-
ation will determine the potential of billfish in the northern part of Ecuador
and Colombia.

The area that this expedition studied from Manta on the north to Salinas
on the south lies between one and two degrees south of the equator, with
the Island of La Plata slightly in the northern part. Here, the coastal shelf,

48 '

which we shall consider to end with the 100 fathom curve, averages about
20 to 25 miles oflshore. The predominant points along this coast line lie
very nearly in a north and south line and the 100 fathom curve follows
about the same pattern until Cape San Lorenzo is reached, then the coast
line and the coastal shelf swing toward the northeast. The coastal shelf in
the vicinity of La Plata Island extends about 25 miles offshore and is of
very uniform depth, averaging from 25 to 35 fathoms. Practically all of
the commercial fishing in this section of Ecuador is done in this relatively
shallow water. During our stay at Salango we found the current to run
generally in a southerly direction. From all reports this seems to hold true
in every season of the year. This flow of water apparently comes from the
southern equatorial current and possibly there is some influence from the
Gulf of Panama on the north. Fiom the mouth of the Gulf of Guayaquil
to the equator the Humboldt Current is far offshore and rapidly diffuses to
the westward. This southerly inshore current that we experienced, coupled
with the flow of water out of the Gulf of Guayaquil may be the origin of
the so-called Nino current that occasionally reaches as far south as central
Peru.

Fishing Methods. Generally, fishing procedures here, especially for
billfish, were the most primitive that we encountered in our preliminary
examination of the west coast of South America: Chile, Peru and Ecuador.
The fishermen in the area are predominantly bottom or reef fishermen.
Before the expansion of marlin fishing in the last ten years, only a few of
the hardier men indulged in shark fishing. Today, in the vicinity of Mania,
there are less than 10% of the local fishermen who have had experience
and practice in marlin fishing in Manta and the surrounding area, princi-
pally La Plata Island.

Due to the lack of swordfish hi these waters, there is very little employ-
ment of the harpoon and very few vessels are equipped for this type of
fishing. While all the species of billfish are inclined to surface, the local
fisherman has never equipped himself with power in his boat so that he
could make any adequate use of the harpoon. All the commercial fishing
boats we encountered that were used in marlin and shark fishing were
powered by sail and oar. The only fishing vessels encountered that were
equipped with motors were those used either as a pickup boat for the catch
of the sailing craft or were employed in bottom fishing, where power was
necessary to haul the long set lines.

In the entire world of commercial billfishing, Ecuador is probably the
most unique. This is the only place in our experience where the fish are
predominantly caught by the use of live bait. All the marlins and sailfish
are caught by slowly trolling a live bonito or a mackerel from a boat under
sail (Figure 8). The native craft employed in this type of fishing is primitive.

• 49

It consists of a dugout canoe, or, as it is called in Ecuador, a "bongo." This
craft averages about 16 feet to 18 feet in length and is manned by one or
two fishermen. It is generally constructed out of a single large log with a
side panel added on to give additional freeboard above the surface of the
water. Most of the boats employed in marlin fishing lash a split balsam
log on either side just above the water line to provide additional stability.
In the fore part of the craft is a mast of about 14 feet to 16 feet in height,
which carries a single lateen sail. Occasionally, in the calmer seasons of the
year a plain foresail is used. The steering of these craft is done by a single
oar seated in a notch in the stern. In the summer months, around the first
of the year, when the periods of calm are encountered, the natives will
either row or slowly scull. Due to the lack of power in these boats, the
fisherman is forced to operate in courses that will set him most advantag-
eously in relation with his home port and the prevailing tradewind is from
the south to the southwest and only occasionally in the summer season is
a light blow encountered from the northerly quadrants. These summer
winds from the north only last a day or two at a time. This obvious limitat-
ion imposed by sail and wind probably has restricted these fishermen in
the development of the potential in their waters as there has never been
any serious exploration here with the proper facilities. It is impossible
to predict where the best billfishing might be encountered.

As stated before, the main area of operation is from the north and
northeast port of La Plata Island, northeast across the channel to Cape San
Lorenzo, which is just southwest of the Port of Manta. While the waters
off the northern part of La Plata Island are very productive of billfish, it
is probably a chosen spot more because fishing is close to shore and their
small sailing craft always have the lee side of the Island and its consequent
shelter for protection. It is very seldom that they operate if the wind force
is in excess of 15 knots.

A typical day's commercial marlin fishing is as follows: The homes of
nearly all these fishermen are on the mainland side. In the peak of the
fishing season during their winter months, the little sailing craft are towed
over to La Plata Island by the pick-up boats that return the fish to the re-
frigeration plant at Manta. During the season these fishermen camp out on
the beach at the Island. As a rule they depart from their sheltered cove at
4:00 to 5:00 o'clock in the morning. The small village and the best anchor-
age is at the northeastern end of La Plata and a scant mile from the princi-
pal fishing ground at the northwestern end. The fisherman either sails or
rows up the shore in the early morning, trolling a feather on a hand line
until he catches a bonito, or large mackerel. This is carefully hooked
through the upper lip and the second or trailing hook is inserted horizon-
tally through the skin about the middle of the first dorsal fin of the bait.

50 •

Some fishermen even employ a third hook on the leader, allowing it to trail
just past the tail of the bonito. As soon as the bait is attached, it is paid out
on the heavy hand line about 100 feet to 125 feet of stern. This live bait is
trolled very slowly, either under sail or by rowing from the shore of the
northern coast out to about a distance of two miles, in a north or north-
westerly course. This course sets the fisherman at the most advantageous
angle in relation with the prevailing wind. They fish this limited area of
about two miles of coast line to a limit of not more than three miles from
shore, until the early afternoon. It was our observation that the majority of
the fish are caught in the early hours of the morning and the majority with-
in a mile from shore. Quite often the black marlin are hooked within 100
yards of shore around the rocky points. Unless the fishing is exceptionally
good, a fisherman seldom operates in the middle or the late afternoon. Dur-
ing the marlin run most of these craft have two men aboard. They take
turns fighting fish on the hand line while the other man steers or paddles
the boat. Occasionally, if the black marlin are not too prevalent, a single
man fishes.

Generally speaking, the oceanic bonito is a hardy bait and when care-
fully hooked will swim very actively when trolled slowly. As a rule, it tends
to troll about 8 to 12 feet below the surface, and in consequence the marlin
and the sharks are seldom observed when they strike. The general pro-
cedure is to give the fish a fairly substantial amount of line when it takes
the bait, in order to hook it as deeply as possible. This, of course, will vary
with the speed of the strike. Due to the extreme shallow water in the
vicinity, the fish are very active on the surface. Both the black and the
striped marlin will jump immediately when hooked. Large black marlin
will jump as many times and show as much activity as small stripers or
sailfish. Each boat carries about 200 fathoms of hand line and it is very
seldom that a large fish will take out the full amount, or any great part of
it. If this should occur, a balsa float is attached and thrown overboard.
The only great loss of the larger fish seems to be due to inferior and weak
line.

On black marlin the average killing time is about two hours. When the
fish is brought alongside it is killed with a club, or as in Cuba, if it is very
active, it is lanced or knifed in the gills and allowed to bleed.

The method of bringing a large fish aboard in these small dugouts is
interesting and amusing. A fish of 800 to 1 ,000 pounds is almost as long as
the boat itself, so the procedure is to pull its head and shoulders over the
combing, at the same time allowing the craft to fill with water, and then it
is a rather simple procedure to float it in. When the fish is secured, the
boat is bailed out. Since their capacity is one fairly large fish, boats im-
mediately return to the village to deposit the fish either in the pick-up

• 51

boat or on the beach. During a large fishing period a boat will catch as
many as three or four fish in a day.

The size of the fishing fleet that operates in the vicinity of La Plata
Island and Cape San Lorenzo varies in size, depending on how good the
fishing is. In a very good marlin year, there will be about 25 to 30 boats
fishing in this area. It was recorded two years ago that this fleet, fishing off
La Plata Island caught 47 marlin in a single day. Of these, over 50%
were black marlin. Considering the size of the fish and the boats used,
this is remarkable, since this is an average of more than a fish and a half
per boat. Generally speaking, it was found that during a good run the fleet
caught between 15 and 20 fish a day. During our stay in these waters, the
fishing was very poor and the best day observed was a catch of eight fish,
with about ten or eleven boats fishing. Until the time we left Salango,
which was the 14th of October, no great concentration of fish had yet
arrived. This area was experiencing the coldest winter season in about
fifteen years and the worst billfishing in the last ten.

The equipment employed by these fishermen is far from adequate. While
these marlin fishermen in an average year have the highest earning power
of any fishermen along the west coast of South America, very little of
their income is reinvested in improvement and the modernization of theii
gear. The hand lines used are about the same quality as the harpoon line
used off Chile. Most of it is handmade out of the strands of old rope or
line. Consequently, its strength is very low in comparison with the diameter
of the line. Much of it probably would test no more than the strength of
a new 39 strand fishing line. Because of this many of the very large black
marlin are lost. The leaders are constructed of old cable or heavy wire.
Most of the leaders are shorter than an average black marlin, being about
ten feet in length. This also contributes to the loss of many fish, since the
tail has the opportunity to chafe the line. The hooks are of any size and
type available. Most of them run from 10/0 to 14/0, the largest sizes being
preferred. Fishing gear is very expensive and not much is imported into
Ecuador. In consequence the fisherman generally has to beg and borrow-
most of his needs.

American interests now established at Manta are bringing in modern
equipment, so in the future the area should see a steady increase in the
production of these fish. In all probability, we shall also see the intro-
duction of small engines in boats of a slightly larger size. This new equip-
ment, when it is in operation, could probably double or treble the yearly
catch.

Economy. Unfortunately, Ecuador has no good production figures on
the catch of billfish at the present time. The best estimation, as has been
pointed out before, is the production of between 600 and 1,000 tons of

52 •

marlin yearly shipped out ol" the port of Manta. It is a safe assumption
that about the same amount is probably consumed by the small fishing
villages up and down the coast. The local fishermen will not bother to
bring a fish into Manta for sale at the refrigeration plant if he is any
distance away.

With a stable currency and no price control set by the government, the
fishermen receive the highest unit price in the three countries that we have
studied. The average black marlin of 400 to 600 pounds will return
$15.00 to $20.00 American. An exceptionally large fish will sell for as
high as $30.00. The average of striped marlin and sailfish runs from $5.00
to $7.00 each, and medium size sharks about the same.

This entire area of Ecuador is extremely rich in bottom fish, and since
fish are the main staple of life, any type of fish is constantly in demand.

This is the only country examined where no price control is employed
and consequently price is solely based on supply and demand. The demand
is always high and the average income of a fisherman is about 30% more
than that of Peru or Chile. With the abundance of fish these natives are
at sea far less than those to the southward. This situation develops a lack
of aggressiveness and a lack of desire on the part of the men to improve
their fishing methods and equipment. In the ofl[ years of fishing the native,
instead of ranging farther from his home base and working more hours and
days, is inclined to say on the beach eking out an existence by minor
agricultural pursuits.

Conclusions. The waters of Ecuador are as rich in sea life as any
area that we encountered along the west coast of South America. Due to
its location at the meeting points of the Humboldt and the South equa-
torial currents, there is a far greater number of species of fish found here
than olT the countries to the south. The only large food fish apparently
scarce is the swordfish. The territorial waters farther offshore and surround-
ing the Galapagos Islands probably contain the largest population of tunas
found anywhere in the eastern Pacific Ocean.

Due to the lack of organized commercial fishing in the coastal waters
and the lack of refrigeration and processing plants, the potential of this
area has probably only been touched. When modern facilities are expanded
here and proper training techniques and equipment introduced, the fishery
production should multiply rapidly. To achieve this, Ecuador should
encourage foreign capital and technology.

53

PLANKTON STITDIE?«*

PLANKTON STATIONS werc occupicd during the months of June through
October, off the western coast of South America, the earlier stations
carried out off Chile, gradually moving northwards to Ecuador in October.
Fifty bottles of plankton were taken and examined. The area studied
proved to be rich in plankton, as exemplified by the appended list of
stations, giving the volumes of each bottle. Upon reading the volumes
of the individual hauls, it was noted that the richest bottles were usually
obtained farther away from shore, during the hours of darkness.

The main constituents of many of the bottles were euphausiids, cope-
pods, salps, chaetognaths, and stomatopod larvae. For example, LM 1,
mainly contained copepods; LM 4, copepods and chaetognaths; LM 5,
salps; LM 6, salps and euphausiids; LM 7, stomatopod larvae; LM 13,
euphausiids and stomatopod larvae; LM 14, copepods, euphausiids, chae-
tognaths, and stomatopod larvae; LM 15, copepods and diatoms; LM 17,
salps; LM 18, stomatopod larvae; LM 20 provided a very good cross
section of various phyla represented in the plankton, although the major
portion of the contents were salps, medusae, chaetognaths, and stomatopod
larvae; LM22 and 23, copepods; LM 25, copepods and medusae; LM 26,
27 and 28, copepods; LM 29, siphonophores, copepods, and euphausiids;
LM 30, copepods and medusae; LM 32, copepods; LM 35 and 36, chae-
tognaths, and copepods; LM 38, chaetognaths and diatoms; LM 39, salps
and siphonophores; LM 41, copepods, and colonial siphonophores; LM 43,
copepods and diatoms; and, LM 44, chaetognaths, copepods, and salps.
The richness of plankton samples collected in these waters should indicate
an excellent fishing area since many larval, juvenile, and adult fish feed
solely on plankton.

The main purpose of the plankton hauls made by the Marron Expedi-
tion was to acquire billfish larvae of the families Istiophoridae (sailfish and
marlin) and Xiphiidae (swordfish) but none were found. The absence of
billfish larvae is probably seasonal. The expedition reported adults in the
collecting areas, none of which were in spawning condition. In general,
few larval fish were collected, but many different eggs were noted, covering
a wide range of groups. The major families of larval fish present were the
Synodidae (lizard fish), Clupeidae (herrings), Myctophidae (lantern
fish), and Nomeidae. Those stations having larval fish were LM 1 (1 fish),
LM 6 (1), LM 9 (1), LM 12 (20), LM 13 (10), LM 14 (5), LM 18
(13), LM 19 (5), LM 20 (6), LM 24 (4), LM 27 (2), LM 32 (2),
LM 33 (141 Synodontidae), LM 35 (5), LM 36 (3), LM 37 (1),
LM 39 (8), LM 40 (2), LM 42 (15), LM 44 (4), LM 45 (7), LM 46

54 '

LM

3

LM

4

LM

5

LM

6

LM

7

LM

8

LM

9

(25), LM 4cS ( 14), LM 49 (L5), and LM 50 (3).

In summarizing the information obtained from the Marron Expedition,
it is a seasonal factor that seems to be the main cause of the few fish col-
lected in spite of the rich plankton present. If the area were again studied
in the months of December and January, a greater quantity of fish larvae
might be obtained. This supposition is based on the early spawning period
of many fish in the Northern hemisphere.

List of Plankton Stations

LM 1 20° 12' S., 70 32' W.; 20 miles W of Iquique, Chile; June 15, 1954

0740-0810; 10 cc. vol.
LM 2 20° 12' S., 70°53' W.; 40 miles W of Iquique, Chile; June 15, 1954

3 cc. vol.
3 20° 12' S., 71° 14' W., 60 miles W of Iquique, Chile; June 15, 1954

2 cc. vol.

20° 12' S.. 71°36' VV.; 80 miles W of Iquique, Chile; June 15, 1954

1525-1555; 33 cc. vol.

20°12' S., 71°57' W.; 100 miles W of Iquique, Chile; June 15, 1954

1740-1810; 123 cc. vol.

20°00' S., 71°53' W.; about 100 miles WNW of Iquique, Chile; June

15, 1954; 96 cc. vol.

19°36' S., 70°21' W.; 5 miles W of Punta Pichalo, Chile; June 20

1954; 0115-0145; 68 cc. vol.

18°27' S., 70°28' W.; 5 miles W of Cabo Lobos, Chile; June 19

1954; 0640-0710; 34 cc. vol.

18°30' S., 70°42' W.; 20 miles W of Arica, Chile; June 23, 1954

1030-1100; 93 cc. vol.
LM 10 18°30' S., 71°3' W.; 40 miles W of Arica, Chile; June 23, 1954

1415-1445; 19 cc. vol.
LM 11 18°30' S., 71°25' W.; 60 miles W of Arica, Chile; June 23, 1954

1720-1750; 173 cc. vol.
LM 12 18°30' S., 71°46' W.; 80 miles W of Arica, Chile; June 23, 1954

2005-2035; 316 cc. vol.
LM 13 18°30' S., 72°7' W., 100 miles W of Arica, Chile; June 23, 1954

2250-2320; 156 cc. vol.

LM 14 18°51' S., 71°31' W., 70 miles WSW of Arica, Chile; June 24, 1954
0400-0430; 41 cc. vol.

LM 15 19° 12' S., 70°55' W., 47 miles NW of Pisagua, Chile; June 24, 1954

0945-1015; 6 cc. vol.
LM 16 19°42' S., 70°41' W., 25 miles WSW of Pisagua, Chile; June 25

1954; 1200-1230; 1 cc. vol.
LM 17 20°28' S., 70°43' W.; 35 miles SW by W of Iquique. Chile; June 30

1954; 1700-1730; 175 cc. vol.
LM 18 20°43' S., 71°17' W.; 70 miles SW by W of Iquique. Chile: June 30

1954; 2135-2205; 60 cc. vol.
LM 19 21°04' S., 72°02' W.; 105 miles W. of Punta Lobos, Chile; July 1

1954; 0315-0345; 70 cc. vol.
LM 20 21°04' S., 7]°41' W.; 85 miles W of Punta Lobos, Chile; July 1

1954; 0610-0640; 70 cc. vol.

• 55

LM 21 21^04' S., 71^20' W.; 50 miles W of Punta Lobos, Chile; July 1,

1954; 0900-0930; 3 cc. vol.
LM 22 21°04' S., 70°59' W.; 45 miles W of Punta Lobos, Chile; July 1.

1954; 1230-1300; less than 1 cc. vol.
LM 23 21°4' S., 70°37' W.; 25 miles W of Punta Lobos, Chile; July 1, 1954

1545-1615; 2 cc. vol.
LM 24 21 °4' S., 70° 16' VV.; 5 miles W of Punta Lobos, Chile; July 2, 1954

0835-0905; 3 cc. vol.
LM 25 20°38' S., 70^18' W.; 5 miles W of Punta Barracos, Chile; July 2

1954; 1630-1700; 6 cc. vol.
LM 26 20°2' S., 70°40' W.; 30 miles WNW of Iquique, Chile; Ju'y 5, 1954

0850-0920; BT sample No. 1; 13 cc. vol.

LM 27 19°54' S., 71°5' W.; 55 miles WNW of Iquique, Chile; July 5, 1954
1235-1305; 4 cc. vol.

LM 28 19°46' S., 71°30' W.; 75 miles WNW of Iquique, Chile; July 5, 1954
1620-1650; 3 cc. vol.

LM 29 19°35' S., 72° 1' W.; 110 miles WNW of Iquique, Chile; July 5, 1954
2030-2100; 113 cc. vol.

LM 30 19°35' S., 71°42' W.; 80 miles W of Pisagua, Chile; July 6, 1954

0400-0110; 27 cc. vol.
LM 31 19°35' S., 71° 15' W.; 55 miles W of Pisagua, Chile; July 6 1954

0815-0845; 5 cc. vol.
LM 32 19°35' S., 70°48' W.; 35 miles W of Punta Pichalo, Chile; July 6

1954; 1145-1215; 6 cc. vol.
LM 33 19°53' S., 70° 16' W.; 5 miles W of Punta Ballenas, Chile; July 6

1954; 1845-1915; 25 cc. vol.
LM 34 4° 10' S., 81°23' W.; about 10 miles WNW of Cabo Blanco, Peru

July 29, 1954; 11 cc. vol.
LM 35 4°00' S., 81° 12' W.; about 12 miles WNW of Mancora, Peru; July

29, 1954; 28 cc. vol.
LM 36 4°00' S., 81° 1' W.; about 1.5 miles W of Pta. Sal., Peru; July 29,

1954; 27 cc. vol.
LM 37 4° 14' S., 81° 15' W.; about 1 mile W of Cabo Blanco, Peru; July 30,

1954; 0910-0940; 1 cc. vol.
LM 38 4°26' S., 81°24' W.; about 7 miles WNW of Lobitos, Peru; July 30.

1954; 1230-1300; 4 cc. vol.
LM 39 3°45' S., 81° 12' W.; 30 miles N. of Cabo Blanco, Peru; August 2,

1954; 0950-1020; 149 cc. vol.
LM 40 3°30' S., 81° 10' W.; 45 miles N of Cabo Blanco, Peru; August 2,

1954; 1225-1255; 37 cc. vol.
LM 41 3°37' S., 80°54' W.; 14 miles W of Zorritos, Peru; August 2, 1954;

1510-1540; 100 cc. vol.
LM 42 3°41' S., 80°40' W.; Zorritos Anchorage, Peru; August 2, 1954;

2045-2115; 23 cc. vol. + 1 large medusae.
LM 43 3°50' S., 80°52' W.; 12 miles NE of Pta. Sal., Peru; August 3, 1954;

0915-0945; 27 cc. vol.
LM 44 4°3' S., 81°26' W.; August 11, 1954; 0715-0745; 63 cc. vol.
LM 45 Near La Plata; 1340-1510; 19 cc. vol.; September 30, 1954.
LM 46 Near La Plata; 1830-1900; September 30, 1954; 105 cc. vol.
LM 47 15 miles NW of Salango; October 3. 1954; 1700-1730.
56 •

OIU

lei^..

oil ^^

15 ^^

17

0l8 ^^"^^

oi4

y

_4°S

iTt. Sal «

0l3

19

• /

y

. 0l2

y

0 5 10 15

IfJape Bla

'^^^ n. milSs

Figure 14. Station Plan. August, 1954.

LM 48 20 miles WSW of La Plata; October 4, 1954; 1300-1330; 207 cc. vol.
LM 49 Inside Salango Island; October 6, 1954; 1300-1340; flood; 53 cc. vol.
LM 50 15 miles NW Salango; October 6, 1954; 1620-1650; 95 cc. vol.

15 miles NW Salango; 30 min. 1605-1635; October 7, 1954.

Off La Plata; October 9, 1954; 1230-1300.

15 miles NW Salango; October 9, 1954; 1645-1715.

H Y » II O t; R A P H I r D A TA

THE DISCUSSION of the hydrographic environments will be made in three
sections according to their geographic locations: Cabo Blanco, Peru;
Iquique, Chile; and Salango, Ecuador.

Cabo Blanvo

The location of the BT lowerings made off Cabo Blanco are given in
Figure 14. vSix of the BT stations were occupied on the same day and ail
ten stations within a ten day period. This is fairly synoptic.

The temperature characteristic of the water mass is a good indicator of
its source in this region of juxtaposition of the water masses from the Peru
Current and Equatorial Countercurrent and for the depths presently dealt
with. This applies even to the surface temperature as the initial tempera-
ture difference of the two water masses is large — much too large to be

• 57

masked by the relatively slow boundary processes of radiation and sea-air
interchange.

The two vertical temperature sections, Figures 16 and 17, clearly show
the water mass of the Equatorial Countercurrent (hereafter ECC) occupy-
ing the surface layer. This surface layer presumably rests on the subtropical
component of the Peru Current, which according to Gunther (1936:160)
flows north beyond Pt. Santa Elena and, as will be seen in a later section,
probably at least as far north as the Isla La Plata. As the ECC crosses
the geographic equator and flows toward the south it will, on the basis of
conservation of angular momentum, acquire anticyclonic vorticity and tend
to hug the South American shores. This would tend to lead to a greater
thickness of the ECC nearer shore. But the observed thickness of this water
mass, as defined by the depth of the thermocline, is clearly shown in Fig-
ure 17 to be smaller near shore than off"shore. Since the observed winds
made at the time of BT lowerings as well as the climatological winds as
given by charts published by Compania Administradora del Guano (Lima,
Peru) are stronger offshore than near shore, it is possible that the greater
thickness offshore may be due to stronger wind mixing. However, although
there are no salinity data to corroborate this and the situation is further
complicated by upwelling, the greater warming of the subtropical water
beneath the ECC at stations 1 7 and 1 8 implies that differential wind mix-

70.9

ire Dldnco

Figure 15. Surface Temperature in degrees Fahrenheit. August. l'-^54.
58 •

3ta llonslb

96. 0

86.9

58.0 7 CO

87.0

55.5

Figure 16. The N-S Vertical Temperature Section in degrees Fahrenheit.

August 11, 1954.

ing is not the major cause for the greater thickness of ECC farther offshore.
More probably the varying thickness of the ECC is better explained in
terms of the varying wind stress westward. For qualitative indication of
this relationship one may use the Ekman wind transport equation (see e.g.
The Oceans, 1946:498):

Tr ^ fw dz = (1/f ) Ta
where Ta is the wind stress at right angle to the current speed, w, and
transport, Tr, while f is the Coriolis parameter and the integration is taken
to large depth.
Take

Ta — kv^ (2)

where k is the product of the density of the air immediately above the
water surface and a resistance coefficient (Taylor, 1916). If the wind
stress is a sole function of x, then differentiating ( 1 ) with respect to x and
considering (2) one has

dTr _ 1 dTa _ k dv^

dx "■ f dx ~ f dx (3)
For simplicity, suppose

v^ = a sin (2nx/L) +b (4)

• 59

where a and b are positive and where b is of such magnitude that v^ is
always positive. Then

dv2

- ^= cos

(5)

dx

2an 2nx

For arbitrary values of k, a and b equations (3) and (5) are plotted in
Figure 18. Regions of divergences are seen centered at x = O and x = L,

3L
while convergences are seen centered at x =z L/2, and x = It is prob-
able that the southerly winds observed at the time of the BT stations
partake of equivalent variation while roughly steadily increasing in the
offshore direction. The wind observations are shown below. Since the wind
force was estimated on the Beaufort scale, a superposing of a relatively
small amptitude wind variation of the kind equivalent to Figure 18 can
be easily overlooked.

Observed Winds at BT Stations

Stations

Observed Winds In
Beaufort Force

Wind
Direction

15
16
17
18

15 Static

iT

^7

56.5

57.5

n. miles

\e

0.

61.5
61.0

"eT.t

59.0 400,

500'

10

I 600

Figure 17. E-W Vertical Temperature Section in degrees Fahrenheit.

August 11, 1954.

60 •

17
I

10
I

15
f

_r>ufrgested looQtlonn
of B.T. statlone
relative to wind
field (curve i; )

(3/2)L

->-x

(d/dx)v

Figure 18. Hypothetical Wind Distribution and Consequent Divergence.

Thus it is reasonable to conclude that the thickness of the ECC water
mass is caused primarily by varying wind and that the positions of the
BT stations relative to the southerly winds are as suggested in Figure 18.

While it is doubtful that the geostrophic relation will hold for this region
more than very approximately because of the certain existence of frictional
and inertial forces, no other approach is possible with the present data.
Nevertheless, use of the hydrostatic and geostrophic relations suggests a
current pattern that is consistent with that of the surface temperatures.
The probable current directions are indicated by arrows in Figure 15.

The thermocline depth, defined as the depth of the top of the layer of
rapid temperature change, is given in Figure 20; this presentation does
not show the deep upwelling evident between stations 15 and 16 in Figure
17.

Saiango

Four BT lowerings were made at nearly the same station at Lat. 1°22'
S., and Long. 80°59' W., 15 n. miles NNW of Isla La Plata. Two charact-
eristics are common to the 5 lowerings: The first is the small cool layer
some 20 to 40 feet deep overlying a warmer and thicker layer; the second
is the very sharp thermocline, the temperature decreasing from 75 to 76°
F to the neighborhood of 60° F in some 30 feet or less. The cool thin
layer is most probably due to the cold southwesterly wind observed blowing
in Beaufort force 3-4 at that time. The sharp thermocline separates the

• 61

Thermoclln^ depth
105 lOOXy

Ptarf Pichal

Stat.

Figure 19. Depth of Thermocline in feet; defined as top of layer of rapid
temperature change. Iquique. July 5, 6, 1954.

Figure 20. Depth of Thermocline in feet; see above figure.

62

warm ECC water from what is very probably the cooler subtropical
component of the Peru Current; no subsurface salinity data are available
to support the identification of the cooler water as the subsurface northerly
extension of the Peru Current, but the temperature data are very suggestive.
The existence of the sharp thermocline in the face of moderate wind stirring
and other turbulences such as due to bottom friction and internal wave to
efface it, requires that there be continuous supply of the two water masses.
Hence, for a steady state, the maintenance of the low temperature near
the topographic bottom requires a cold bottom current to carry away
the heat diffused from above. The relative thicknesses of the water masses
of the ECC and of the Peru Current further implies that the Peru Current
is flowing there at a greater speed than that of the ECC. The causes for
the varying depth of thermocline which changed from 100 to 170 feet
are uncertain.

In this southerly location the ECC water mass is absent. The surface
temperatures rise steadily from the coast out to the open Pacific as is
generally observed. But the presence of a relatively strong thermocline
indicates that no upwelling was in progress and that the warmer water
above the thermocline must have been advected into the reeion since it is

^

3-1700

5 VII 54

Sl.c 4-£ll0

5 VII 54
61.7

KEY
1 cm = I'^F
1 cm = lUO ft. dentil

8-19a5
6 VII 54
60.1 ;

/

8- 131b
5 VII 54
60. e

Ft.
ICO .

EOO

:!oo

'station located at
15 n. oiles NNW oF THE Isla iialungo

** station located in 185 ft.
of water northeast of
I. La Plata

Figure 21. Bathythermograph Traces.

63

quite improbable that summer heating in the face of predominantly south-
erly winds (and hence upwelling tendency) can effect thermoclines of such
magnititude (see Figure 21). Gunther (1936) showed, in his Figure 17,
a warm tongue advecting from the ocean Pacific into the region south of
Arica, about 100 n. miles north of Iquique. It is likely that the eddy, whose
warm branch forms the water mass above the thermocline, is bounded
geographically to this area because of the abrupt change in the direction
of the coast line at Arica.

The depth of the thermocline, defined as the top layer of rapid temper-
ature change, is given in Figure 19. The thermocline depth deepens sea-
ward and southward indicating that the warm branch of the eddy is south
of the approximate line drawn WNW of Iquique at this time.

22-0815
le VIII 54
70.7

20-0710
17 VIII 54
69.4

See ?lKure 3 for Key

Figure 22. Bathythermograph Traces.

Summary and Recommendations

The surface boundary between the Peru Current and Equatorial Counter
Current was located by the bathythermograph at north of Cabo Blanco and
the subsurface northern extension of the Peru Current was thought to
extend as far north and near shore as the Isla La Plata, Ecuador. The warm

64

branch of the eddy, first observed by Gunther, olT Arica, was found to
extend as far as Iquique and south.

In this region of interplay of water masses each with distinctive temp-
erature characteristic, the bathythermograph is a valuable instrument
particularly north of 10^ S. However, for more complete analysis and
more positive conclusions, BT lowerings should be supplemented with
salinity samplings and rigorous meteorological observations. A more
complete and detailed oceanographic coverage of area surveyed is another
desirable that must be fitted into the biological plans of any future studies.

65

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