UNION OF ‘SOUTH AFRICA.
“province OF THE GAPE. 0 s00n Hore. | |
MARINE
BIOLOGICAL REPORT
No
3ist DECEMBER, 1912.
AND FOR THE HALF YEAR ENDING
80TH JUNE, 19138.
—.
Pes
SS
J
4
oe
rior UNION OF SOUTH AFRICA.
PROVINCE OF THE CAPE OF GOOD HOPE.
MARINE
DPIoOLlOGICALVaREPeORM
Noam
FOR THE YEAR ENDED 31ST DECEMBER, I9Q12.
AND
FOR THE HALF YEAR ENDING 30TH JUNE, 1913.
Co be Presented to the Provincial Council.
CAPE TOWN: Z2ES II
CAPE TIMES LIMITED, GOVERNMENT PRINTERS,
1913.
[C.P. 5—’13.]
B.4/22274.750.6.13.
C.T.Ltd.—B. 1210.
—*e
mora.
TRUM
a ,
—-
THE PROVINCIAL SECRETARY,
StR,—I have the honour to submit the following special
Reports on the Cape Crawfish and Crawfish Industry, the
Clupeidee (Herrings, Anchovies, White Bait, &c.) of South
Africa, and the proposed Acclimatisation of “ Millions,” with
recommendations on the practical questions which have arisen
in connection with these subjects.
I have the honour to be,
Sir,
Your obedient Servant,
[Dae GILCHRIST.
Cape Town,
30th June, 1913.
[C.P. 5—'13:]
CONTENTS.
I. THE CAPE CRAWFISH AND CRAWFISH INDUSTRY.
Introduction
1G;
2)
iP)
History of the Crawfish Industry
Experimental hauls of Crawfish in and around Table Bay
. Observations at the Marine Laboratory at St. James to
determine the breeding habits, &c., of the Crawfish
. Geographical distribution of the Cape Crawfish
. Sexual differences in the Crawfish
. Early stages of the Crawfish
. Habits of the larval Crawfish
. Age, rate of growth, &c., of Crawfish
. Enemies of the Crawfish
. Food of the Crawfish
. Migration and movements of the Crawfish
. Life History of the Crawfish
. Preservation of the Crawfish
II.—REVIEW OF THE SOUTH AFRICAN CLUPEIDA C(CHERRINGS, SARDINES,
ANCHOVIES, WHITE Balt, &C.)
IIl.—THE PROPOSED INTRODUCTION OF “ MILLIONS”
[C.P. 5—’13.]
PAGE
UNION OF SOUTH AFRICA.
MARINE BIOLOGICAL REPORT.
I. THE CAPE CRAWFISH AND CRAWFISH
INDUSTRY.
INTRODUCTION.
Much difficulty has been experienced in dealing with variou
questions which have from time to time cropped up with
regard to the Crawfish Industry. In the early stages of this
industry it seemed to be the general impression that the
supply of the fish was inexhaustible, and that no steps need
be taken to prevent over-fishing and the possible extermina-
tion of the animal. Very soon, however, it was observed
that, apparently in consequence of the very extensive opera-
tions of the canning companies, the supply was being se1iously
endangered, and the question of some restricting measures
which might safeguard the industry was raised at the instance
of the canning factories. Measures of this nature generally
take the form of (1) a close season, during which no fishing
is allowed, or (2) a size limit, or size below which no fish are
allowed to be taken, thus protecting the immature forms
and giving them a chance to breed.
It was finally resolved to impose a close season. Little or
nothing, however, was known as to the times of spawning or
the habits generally of the crawfish, which would indicate
at what time of the year this close season should be fixed
in order to be effective. Naturally the fishermen, though
generally convinced that a close season was desirable, did not
desire that this should interfere with their fishing operations,
and the close season was fixed for the months of the year in
which little or no fish were caught, namely, when they were
in a condition known as “‘ sick.’’ The question has, therefore,
been raised as to whether this measure is really effective, as
no extensive fishing would take place during this period in
any case. Clearly what is desired is further information as to
the times of spawningfand the life history of the fish generally.
[C.P. 5—’13.]
2
Again, the imposition of a size limit was suggested. Atten-
tion was drawn to the practice of catching very small craw-
fish, and it was suggested that the destruction of these im-
' mature forms was responsible for the falling off of the supply.
These small crawfish form a particularly palatable dish, and
it was pointed out that in many cases young forms of various
sea animals were extensively utilised for food purposes without
deleterious effects, and, besides, there were some experienced
fishermen who maintained that these small forms were not
the young of the common crawfish, but belonged to another
and smaller species, which did not grow larger.
A size limit was, however, imposed, and it was made illegal
to catch these small crawfish. Here again it was clearly in-
dicated that what was wanted was further and reliable scientific
information, particularly with regard to the early and possibly
somewhat different stages of the fish.
Even these restrictions were not deemed sufficient, and it
was decided further to protect the, females “in berry,” that is,
carrying the eggs externally, as is the habit of the crawfish.
This appears on the face of it to be a very rational method
of dealing with the difficulty, especially if it be reckoned
that the destruction of a female carrying thousands of eggs
means not only the destruction of one individual but of thou-
sands of young. However plausible this may be, there are
reasons, as will be seen later on, for suspecting that there is
a fallacy in this line of reasoning. What is wanted is further
information as to the time of maturity, time of life of greatest
fertility, the life history of the young, time and cause of
greatest fatality among the young, etc.
There is a special need for such investigation at the present
time, as, owing to certain circumstances which will be indicated
later on, the industry has entered on a new and prosperous
phase, so that for the last few years the capture and canning of
the fish for export purposes has been energetically carried on
—so energetically, it is stated by some who are engaged in
the industry and presumably in a position to know, that it can
only last a few years longer. Attracted by the success of the pre-
sent canning companies, several others are now about to begin
operations on an extensive scale, for which reason it is all
the more urgent that effective measures be devised for the
safeguarding of the industry from a fate similar to that which has
befallen the lobster industry of Europe and America.
The following notes on the Cape Crawfish, its life history
and habits, are intended as a contribution to a fuller know-
ledge of some of these points and a possible solution of the
practical difficulties met with.
a”
e3)
The notes'are arranged under the following headings :
. History of the Cape Crawfish Industry.
2. Experimental hauls of Crawfish in and around Table
Bay.
3. Observations at the Marine Laboratory at St. James to
determine the breeding habits, &c., of the Crawfish.
. Geographical distribution of Cape Crawfish.
. Sexual differences in the Crawfish.
. Early Stages of the Crawhsh.
. Habits of the larval Crawfish.
Age, rate of growth, &c., of Crawfish.
. Enemies of the Crawfish.
. Food of the Crawfish.
. Migration and movements of the Crawhsh
. Life history of the Crawhsh.
. Preservation of the Crawfish.
I. HISTORY OF THE CAPE CRAWFISH INDUSTRY.
The crawfish though a valuable article of food, easily pro-
cured and occurring in large numbers at the Cape, seems to
have been practically overlooked in the early days. Frequent
Reference is made ‘to the “fine’,Cape fishes, many of the
common kinds being mentioned by name, such as snoek,
steenbras, herring, harders, and even soles, but there appears
to be only casual reference to “some fine crawfish” presented
to Van Riebeek by two or three Hottentots. (See Precis of the
Archives, 4th September, 1852.)
This neglect of a valuable article of food was typical of much
later days and its value does not seem to have been appreciated
except by the natives. This is all the more remarkable as its
representatives in Europe, the Langouste, Spiny or Rock
Lobster (Palinurus vulgaris), to which it is not inferior, is an
important article of food, particularly in France and on the
coast of the Mediterranean and its islands. In London it
commands a good price and its flesh is by many considered
quite as delicate as that of the true lobster. It is significant
also that in Natal a species of crawfish is found but is rather
rare, and is much more highly valued than the Cape crawfish is
at the Cape.
About the time of Lamarok (1744-1829) the Cape crawfish
became known to the scientific world in Europe and is men-
tioned by this author in M.S. (in Museum, Jardin des Plantes)
under the name Palinurus lalandii, that is, a species of the
Langouste (Palinurus vulgaris) so well known in France. It
is probably due to the fact that a crustacean, very similar to the
Cape crawfish, is so well known and esteemed in France that
some of the earliest enterprises in connection with the industry
at the Cape were French in origin.
[C.P. 5—’13.]
lan
WNH OO OI AUN
4
Before these however the potentialities of the industry were
realised and attempts were made within the Colony itself to put
it on a proper basis. The Right Honourable John X. Merri-
man was the pioneer in the new industry and, although his
enterprise met with little encouragement, and even with ridicule
from some quarters at the time, it marks the first successful
step im a series of experiments, which have led up to the
present condition of the industry.
In the year 1874, 1n conjunction with Mr. Charles Manuel,
he imported an expert in the canning business from Messrs.
Crosse and Blackwell. A beginning was made with the
canning of crawfish, but with limited success. Attention was
then turned to fruit and jam making, and, with such results,
that the produce found a ready sale. Experiments on crawfish
canning, however, were continued, and a satisfactory method
for preserving it was at last devised. The canned products
were exhibited at the Philadelphia Exhibition of 1876, and
were awarded a Bronze Medal. In 1875 Mr. Merriman joined
the Government, and disposed of the business to Messrs King
and Son, but, in consequence of some difficulty with the
operator, the enterprise was allowed to drop.
It was not again until 1890 that the idea of canning the
crawfish was taken up. In that year Baron Eugene
Oppenheim, the Consul for the Transvaal Government,
observing the large quantities of crawfish to be
easily caught in Table Bay, conceived the idea of
canning and exporting them to Europe. Along with his
brother he formed a syndicate under the name of the
“South Atlantic Lobster Syndicate,” and, utilizing an old
mill between the Old Somerset Hospital and the Docks as a
factory, commenced to experiment in preserving the fish in
tins. Mr. Carl Poppe was manager. The crawfish were got
in abundance, chiefly from beyond the Woodstock beach,
near Milnerton, or at Mouille Point, and no difficulty was
experienced in procuring the raw material in sufficient quantity.
From this factory about 4 or 5 thousand cases were turned out
per year (about 96 small and 48 large tins in a case with an
average of about 2 crawfish per tin). At this time the crawfish
was not only abundant, but very large specimens were often
taken. Owing, however, to difficulties in devising a proper
method for preserving the fish and the consequent bad condition
of the produce when placed on the market (Paris chiefly)
there was little sale for the crawfish, and this syndicate soon
went into liquidation.
At a later date Baron Oppenheim, who still had faith in
the ultimate success of the enterprise, started another factory
under the name of ‘‘ Trebor Bros.”’ at Woodstock about the
year 1893 under the management of Mr. Lefevre.
3)
Soon afterwards another small factory was started at
Woodstock by Captain Malcolm near the first, and shortly
afterwards yet another by Mr. Hansel Maier, where the
present Woodstock factory (Ovenstone’s) now is.
All of these, in spite of apparently promising beginnings,
were ultimately closed down, the promoters having lost
heavily in the undertaking.
Soon afterwards (1894), however, the ‘‘ Cape Canning
Company’ was started at Mouille Point, and, after losing, it
is said, about £17,000, went into liquidation like the Trebor
Bros. Company two years before.
Some idea of the quantity of Crawfish procured by this
Company may be obtained from the following figures of a
year s catch :—
1894, July, 29,962
August, 97.265
September, 124,580
October, 240,160
November, 60,150
December {close season)
1895, January (close season )
February, 29,360
March; 62,420
April, 67,640
May, 72,320
June, 57,900
Total for one year, 841,757
The chief cause of failure seems to have been defective
canning and the impossibility of competing with the canned
lobster of America, which was then in great abundance.
It was during the operation of this last Company that fear
was entertained that the supply of crawfish was being seriously
endangered, and the necessity was represented to Government
of some legislative measure for the imposition of a close season,
and the prevention of the capture of the young immature
forms. Considerable alarm was also felt lest a similar fate
to that of the lobster of the Northern Hemisphere should
befall the Cape lobster. In Europe, America and Canada so
great had been the unrestricted operation in this industry
that it had practically ceased to exist on the former large
scale. It was partly due to this extensive fishing and the
consequent cheapness of this article (gd. per tin in Paris in
1895) that the demand for the Cape article fell off.
[C.P. 5—’13.]
6
For several years after this the factories practically ceased
to exist at the Cape, and for the first time again a small factory
was started at North Bay (Saldanha Bay) by Hinchliffe and
Holland in 1902. This site proved unsatisfactory, and the
factory was transferred to Hoetjes Bay, not far off. An
idea of the extent of the operation of this company may be
obtained from the fact that the annual wages paid to Colonial
fishermen amounted to about £3,500 per annum. The same
firm later on erected another factory at Steenberg’s Cove.
From this factory alone during the year 1912 over 10,000 cases
of crawfish (representing over a million fish) were exported,
realising 37s. 6d. per case of 96 half-pound tins.
Meanwhile a new factory was started at Hout Bay by Plessis
in 1903, and met with success. Recently another has
appeared at Woodstock (Ovenstone), another near the Docks,
and several others are contemplated.
With improved method of packing, along with an improved
market owing to the decay in the lobster industry, the
potentialities of the industry are being recognised. The
chief market for the fish was, and is still largely, Paris,
and, for long, the London market would not look at the
article, owing, it is said, to bad packing. This impression was
removed at some trouble, and samples of what could be
produced were submitted (by Mr. Reid) to a London firm.
These compared so favourably with the canned lobster on
the market that an offer was made to accept the annual output,
(30,000 or 40,000 cases) up to a quarter of a million cases,
a fact which will indicate the possibilities of the industries
now that the great markets of Europe are prepared to accept
the article.
2. EXPERIMENTAL HAULS OF CRAWFISH IN AND AROUND TABLE
Bay.
In order to procure definite and reliable information with
regard to the occurrence and condition of the crawfish at
different times and places, a number of experimental hauls
under the supervision of the Fisheries Officer were
made in Table Bay and its neighbourhood (off Wood-
stock Beach, near Robben Island, and near Hout Bay).
These hauls were made with an ordinary crawfish net, 39
inches in diameter, down for a period of quarter of an hour.
Notes were taken of locality, state of sea, depth and tempera-
ture, and the size of each specimen was measured, from rostrum
to end of carapace. This method of measurement was adopted
in preference to the method specified in the fishery regulations,
as being more accurate and not differing materially from it.
The legal method is from the base of the eyestalk to the end
ii
of the carapace or shield, and is slightly smaller than the
measurement here used, in about the proportion of 8 to 9.
For purposes of comparison the various sizes are classified
into those of 1 inch up to, but not including 2 inches, 2 inches
up to, but not including 3 inches, and so on, this being ex-
pressed by the numbers I +, 2 +, etc.
The condition of the fish is indicated by the distinction
between those in (1) hard old shell, (2) hard new shell, (3) soft
old shell, and (4) soft new shell.
No. I.
Dates) 2/10/12. Number of hauls: 24:
Locality : South East of Robben Island.
Condition of sea: Smooth, with heavy westerly swell.
Depth: 13 fathoms.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+,8+
Rlarcvoldishellh 2 a ee Ae Oe 83) 98
Hard new shell .. ‘ a by bis i ; sy
Softold'shell >... -.. Ae = ae OP Ch Me
Soft new shell .. .. I 3 0) I
Total of males: 290. Average number per haul : 12.086.
Average size: 5.65 inches.
Female Crawfish.
None.
No. 2:
Date: 6/11/1912. Number of hauls: 24,
Locality : South East of Robben Island.
Condition of sea: Smooth, with slight westerly swell.
Depth: 13 fathoms.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+,7+, 8+,
Hard-old:shell*..-°.< Ae eit: 2 7 5 I
Hard new shell .. ir ae a :
Soft old shell a He ne ne
Soft new shell .. Pik gila *2Or mcr’ oe
Total of males: 61. Average number per haul : 2°541 e
Average size: 2,7 inches.
Female Crawfish.
None.
[(C.P. 5—’13.]
8
No. 3.
Date’; 12/1r/19r2. . Number of-hauls =) 4:
Locality: Near the sewer, off Woodstock Beach.
Condition of sea: Choppy.
Depth: 24 fathoms. Temperature 50-8°.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+,
Hard oldshell .. 2 Ory ar a ee a By. ;
Hard new shell .. :
Soft old shell
Soft new shell oe ae NE Be 5
Total of males: 11. Average her haul: 2-75.
Average size: 1°18 inches.
Female Crawfish.
Sizeéininches I+, 2+, 3+, 4+, 5+, 6+, 74, Om
Hard old shell 2.5 45 | = i a tie
Hard new shell .. :
Soft old shell
Soft new shell : a
In berry Fo ais is 2
In eyed berry sa Ro pec, Mee eee ;
Total of females: 14. Average number per haul: 3°5.
Average size: 1°78 inches.
Total number of males and females: 25.
Average size: 1°48 inches. Average number per haul : 6-25.
Noy ie
Date: 13/11/1torz. Number of hauls: 16.
Locality : South East of Robben Island.
Condition of sea: Choppy, with slight westerly swell.
Depth: 13 fathoms. Temperature: 50:6°.
Male Crawfish.
Size in inches I+, 2+, 3+, 4+, 5+, 6+, 7,+, 8+
Hard.oldishelly 77. ae ah =: oe 4 2 Us
Hard new shell .. a: an See Br fe
Soft old shell
Soft new shell .. .. ae 7 ats 2 Tae
Total of males: 9g. Average number per haul: -562.
Average size: 5°33 inches.
Female Crawfish.
Sizeininches I+, 2+, 3+. 4+, 5+, 6+, 7+, 8+
imandvold-shtelliy 2. 3. ee I a
Hard new shell .. oa oats <
Soft old shell
Soft new shell
In berry
In eyed berry Te ote CED Pe aoe — ew Meer
Total of females: 3°77. Average number per haul: -25.
Average size: 4 inches.
Total number of males and females: 13.
Average size : 4°55 inches. Average number per haul: -812.
Nowe:
Date: 28/11/1912. Number of hauls: 8.
Locality: Between ‘America Wreck” and Woodstock
Beach.
Condition of sea: Rough and very choppy.
Depth: 4 fathoms. Temperature: 50-7°.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard-old shell 2: - 11 Gi
Hard new shell ..
Soft old shell
Soft new shell cate caer N, ran Meat hy vette Nie
Total of males: 18. Average number of hauls: 2-25.
Average size per haul: 1°39 inches.
Female Crawftsh.
Sizeininches I+, 2+, 3+, 4+ 5+, 6+, 7+, 8+
Hard old shell
Hard new shell ..
Soft old shell
Soft new shell ioe ie ae a
In berry BSeme se ai 5 3 2
In eyed berry Sa, 2 Shaaberbod MGhuom ed icy Saeco
Total of females: 10. Average number per haul: 1:25.
Average size: 3-7 inches.
Total number of males and females: 28.
Average size: 2°54 inches. Average number per haul: 3:5.
[C.P. 5—’13.]
10
No. 6.
Date: 5/12/1912. Number of hauls: 16.
Locality : Near the mouth of the sewer at Woodstock Beach
and near the ‘‘ America Wreck.”
Condition of sea: Very smooth, calm and cleat.
Depth: 4 to 5 fathoms. Temperature: 50-4°.
None caught.
No. 7.
Date: 12/12/1912. Number of hauls:. 14.
Locality: Between “ America Wreck” and Woodstock
sewer.
Condition of sea: Choppy, from the South East.
Depth: 5 fathoms. Temperature: 50-4°.
Male Crawfish.
Size in inches I+, 2+, 3+, 4+, 5+, 64+, 7+, 8+
Hard old shell .. 4 25. e oe 3 4 3
Hard new shell ..
Soft old shell
Soft new shell Ge ee ne eek, a ee
Total of males: 16. Average number per haul: 1-142.
Average size: 4:3 inches.
Female Crawfish.
Size ininches I+, 2+, 3+, 4+, 5+, 6+. 7+, 8+
Hard old shell .. 2 2 : ¢
Hard new shell ..
Soft old shell
Soft new shell a Re te He
In berry tena | Was Qe ee I
meyed perky, sesnuee- = 2
Total of females: rr. Average number per haul: -785.
Average size: 2°42 inches.
Total number of males and females: 27.
Average size. 3°36 inches. Average number per haul: 1-928.
No. 8.
Date: 17/12/1912. Number of hauls: 14.
Locality: Between ‘‘ America” wreck and Woodstock
Beach.
Condition of sea: Very calm and oily.
Depth: 5 fathoms. Temperature: 50°6°.
II
Male Crawfish.
Sizeininches 1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Beaten Ol@ssiaelli oe.) aia MOM Tyee hts) | ere t
Hard new shell ..
Soft old shell
Soft new shell eer es Ue ee es ree ee
Total of males: 19. Average number per haul: 1-357.
Average size: 1-78 inches.
Female Crawfish.
Size in inches 1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell” 3. 12 rks bs 33 Se ui
Hard new shell .. Sr ik aa
Soft old shell
Soft new shell «cy OO, wots
In berry U 6
In eyed berry § ee ea
Total of females: 22. Average number per haul: 1-571.
Average size: 2 inches.
Total number of males and females: 41.
Average size: 1-89 inches. Average number per haul : 2-928.
No. 9.
Date: 30/12/1912. Number of hauls: 14.
Locality. Near the “America” wreck.
Condition of sea: Choppy from South East.
Depth: 5% fathoms. Temperature: 50-2°.
Male Crawfish.
Size in inches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Itard-old'shell -.. =~. ie is I 2 5
Hard new shell .. oe = *
Soft old shell Rees Rr eT Os Wie ae tn eee
SoiemeweSWella (cc. whe: <tc ee Sepelie Naes yey Re Roi Bees
Total of males: 310. Average number per haul: +714.
Average size: 5:6 inches.
Female Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell Fr a te
Hard new shell ..
Soft old shell
Soft new shell
In berry ree Raia Re Ms ce
inypevedaberry= We wots ee Ae Tepes Mes cee Viet
(CP. 5= 13: | G
17
Total of females: 1. Average number per haul: -o71.
Average size: 4 inches.
Total number of males and females: 11.
Average size: 4°8 inches. Average number per haul: -785.
No. I0.
Date: 7/1/1913. Number of hauls: 14.
Locality: Between ‘‘ America’? wreck and Woodstock
sewer.
Condition of sea: Choppy from North.
Depth: 54 fathoms. Temperature: 50:6°.
Male Crawfish.
Size in inches I+, 2+, 3+, 4+, 5+, 64+, 7+, 8+
Hard: oldshell¥. 2) 2. sa ne Os ae 3
Hard new shell .. .. oa iT 6 ne Sk
Soft old shell
‘Soft new shell
Total of males: 16. Average number per haul: 1-142.
Average size: 4°31 inches.
Female Crawfish
Sizeininches I+, 2+, 3+, 4+, 5+, 64+, 7+, 8+
Hard old shell
Hard new shell ..
Soft old shell
Soft new shell
In berry \
In eyed berry § IY :
Total of females: 21. Average number per haul: 1°5.
Average size: 3°I inches.
Total number of males and females: 37.
Average size : 3:7inches. Average number per haul : 2-642.
Noire
. Date: 10/1/1913. Number of hauls: 14.
Locality: Between ‘‘ America” wreck and Woodstock
sewer.
Condition of sea: Very choppy, from East.
Depth: 5} fathoms. Temperature 50°8°.
13
Male Crawfish.
Sizeininches 1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hanevoldshelly 35° (255) Pk. 5 ee PAP eS kee
Hard new shell .. Mae San) ied eh ate oad
Soft old shell Ty ho eee
Soft new shell .. .. Re: 3 Z Teh iw <t My:
Total"of males: 24. Average number per haul: 1-714.
Average size: 4°45 inches.
Female Crawfish.
Sizeininches I+, 2+,3 +, 4+, 5+, 64,7 +, 8+
Hard old shell ee a er eee
Hard new shell”.
Soft old shell
Soft new shell
In berry \
In eyed berry §
Total of females: 3. Average number per haul: -2r4.
Average size: 3°33 inches.
Total number of males and females: 27.
Average size: 3-89 inches. Average number per haul : 1-928.
2 ie
Noo 12
Date: 14/1/1913. Number of hauls: 14.
Locality : Near the ‘“‘ America” wreck.
Condition of sea: Very calm and clear.
Depth; 5 fathoms.’ Temperature : 50-8°.
None caught.
Noir:
Date: 21/5 /r9r3. Number of hauls.:), 14
Locality : Between the ‘“‘ America”? wreck and Woodstock
sewer.
Condition of sea: Very choppy from South East.
Depth: 5% fathoms. Temperature: 50-8°.
Female Crawfish.
Sizeininches +, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old,shell ”. . a ay. Ur Ntad Penad ai Me cata nae ae
Hard new shell ..
Soft old shell *
Soft new shell *.. ioe (ee
In berry il (
In eyed berry { : 2 5 ve ee ee ee oe
Total of females: 7. Average number per haul: °5.
Average size: 2°71 inches.
[€.Pe—*13, |
14
No. 14.
Date: 28/1/1913. Number of hauls: 14.
Locality: Between “‘ America”? wreck and Woodstock
sewer.
Condition of sea: Very calm.
Depth: 54 fathoms. Temperature: 50:2°.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell .. .. as as ae ¥, 2 oe ee
Hard new shell ..
Soft old shell
Soft new shell Ree set ra a i
Total of males: 2. Average number per haul: -142.
Average size per haul: 6 inches.
No. 15.
Date: 4/2/1913. Number of hauls: 14.
Locality : Near ‘‘ America” wreck.
Condition of sea: Very choppy from South East.
Depth: 54 fathoms. Temperature: 50-2°.
Male Crawfish.
Sizein inches 1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell : oe ae ue ae = =f 2%
Hard.new shell =. ...% a sas ws 4 2
Soft old shell
Soft new shell sic aA of a: a a om
Total of males: 6. Average number per haul: -428.
Average size: 5.33 inches.
Now 16:
Date: 6/2/1913. Number of hauls: 14.
Locality : “‘ Bad Tamboer”’ entrance to Hout Bay.
Condition of sea: Very choppy, sight North West wind.
Depth: ro fathoms. Temperature: 50-4”.
Male Crawfish.
Size in inches I+,,2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell .. .. oe i Ase eae 8
Hard new shell .. :
Soft old shell
Soft new shell ; a oe a =i Bias) bo
Total of males: 53. Average number per haul: 3-785.
Average size: 4°71 inches.
T5
Female Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Prancoldyshell ee. eae te ATO Sie te ayy eet Tees
Hard new shell ..
Soft old shell
Soft new shell
In berry
In eyed berry cc ieee A Rae Sia Oram Snore aaa
Total of females: 27. Average number per haul: 1-928.
Average size: 3.3 inches.
Total number of males and females: 8o.
Average size: 4 inches. Average number per haul: 5.
No-17-
Date: 12/2/1913. Number of hauls: 4.
Locality : Near the “‘ America ” wreck.
Condition of sea: Very rough, South East swell.
Depth: 53} fathoms. Temperature: 50-2°.
None caught.
No. 18.
Wate: 14/2/1913. . Number of hauls: 14.
Locality : Near Duiker Point (Cape Town direction).
Condition of sea: Very choppy, heavy westerly swell.
Depth: 84 fathoms. Temperature: 50°25°.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell : ny ee i UN: iN
Hard new shell ..
Soft old shell a ue. ca i Ne Le:
Soft new shell .. .. ae Site MEAS Vali Bi Aveiece ae
Total of males: 31. Average number per haul: 2-214.
Average size: 4°67 inches.
Female Crawfish.
Size in inches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell pai Wahe We tte © na ee) Rane ak eee oe Weer
Hard new shell .. xb ' 17
Soft old shell
Soft new shell
In berry
ETRE VCCU DELI hk iae Set |! Nn aid eA eee |) acl a ae
Total of females: 28. Average number per haul: 2.
Average size: 1-6 inches.
Total number of males and females: 59.
Average size : 3°13inches. Average number per haul : 4-214.
[C.P. 5—’13.]
16
No. 19.
Date: 18/2/1913. Number of hauls: 14.
Locality : Near ‘‘ America”? wreck and Woodstock sewer.
Condition of sea: Very calm and smooth.
Depth: 53 fathoms. Temperature: 50°8°.
None caught. ;
No. 20.
Date: 24/2/1913. Number of hauls: 14.
Locality : Duiker Point (Cape Town side of).
Condition of sea: Very choppy, heavy westerly swell.
Depth: 63 fathoms. Temperature: 40:8°.
Male Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell
Hardimew shell. 7 a 6
Soft old shell eis 3 al lle 8, Sa a ee
Soitmew shell 2 5. ee, ee, 1a TO 7
Total of males: 27. Average number per haul: 1-928.
Average size: 5°48 inches.
Female Crawfish.
Sizeininches I+, 2+, 3+, 4+, 5+, 6+, 7+, 8+
Hard old shell
Hard new shell .. .. Pee, 554 ee eae a sf ae
Softiold ‘shelly _ fy) ia cae a. fs Ap oe a
Soft new shell , ae ie A te
In berry
In eyed berry
Total of females: 73. Average number per haul: 5-214.
Average size: 3°24 inches.
Total number of males and females: 100.
Average size: 4°36inches. Averagenumber perhaul: 7-142.
No. 21.
Date: 11/4/1913. Number oi aulse rz.
Locality : Opposite the Milnerton Hotel and “ America”
wreck.
Condition of sea: Calm, with heavy westerly swell.
Depth: 54 fathoms. Temperature: 50°8°.
Male Crawfish. .
sizeiminches. 4, 2+, 3+, 4+, 5+, 64, 7+, 8+
Hardoldshell .. .. i o, fe ag: 2
Hard newshell .. .. ste =f Re ae a i yy
Sottold shelly. 2.04% a LES, Ieee ae de os ae
Soft new shell a
Total of males: 2. Average number per haul: -r16.
Average size, 6 inches.
Female Crawfish.
SIZembinches. Bb, 2+, S04 +) 5th 66 4) 9 4 8
ictecholdishell 24 9%5 °°: i 6
Hard new shell .
Soft old shell
Soft new shell
iin berry.
In eyed berry a: chede By ccte ek ae See) Ys.
Total of females: 7. Average number per haul: -583
Average size : 3°9 inches.
Total number of males and females: 9.
Average size : 4-95 inches. Average number per haul :
Ni
Qi
No. 22.
Date : 23/4/1913. Number of Hauls: 12.
Locality : Opposite the Milnerton Hotel.
Condition of sea : Moderate, long heavy swell from the west.
Depth: 8 fathoms. Temperature : 60-0°.
Male Crawfish.
eize mumches. 1-24, 3 45/4 aa, 64 7+, 8+
Hard old shell ve a ae = ae
Hardinewshell. ).. 7 .. I 4 4 Sey "es
Soft old shell
Soft new shell
Total of males: 12. Average number per haul: r.
Average size: 3°75 inches.
Female Crawfish.
None caught.
(CP 513%]
18
These data are as yet not sufficient to throw much light on
the habits of the crawfish, but some general conclusions may
be indicated.
Males.
A large number of males by themselves were found in
13 fathoms near Robben Island on the 2nd November. Most
of these still had their old shell, but some had moulted. On
the 6th of the same month a somewhat similar condition was
met with.
Meanwhile in shallow water (2} fathoms) off Woodstock
Beach a small number of immature males were found together
with females.
The first locality was visited again on the 13th November
and a smaller number of males were found, some still in the
old shell, some in the new, together with 4 mature females in
hard shell.
The second locality (off Woodstock Beach) showed, as
before, small males together with females in berry. On the
12th, in 5 fathoms, in addition to small males, a number of
large males were present with mature and immature females.
Five days later conditions were somewhat similar, but only
one large male was found. On the 7th January adult males
were got with berried females in about equal numbers. Later,
on the roth January, the adult males were much in excess
of the females (3 berried), and there was a marked absence
of small males. On the 14th and 21st no males were got ;
on the 28th, 2 large males and no females, and again on the
4th February large males but no females were found.
It would appear from this that the large males had retreated
to deep water (13 fathoms) and there cast their shell, the
smaller males in the meanwhile being in shallow water with
the berried females. Later on, the large males with new shell,
appeared in the shallow water apparently driving off the small
forms and adult females. It will be seen by glancing over
the schedules that very seldom are adult males procured
together with young forms. That the larger fish drive off the
smaller is also indicated by the fact that it has been observed
that in fishing operations the smaller fish are at first got and
a little later only large fish. The behaviour of the animals
in the tanks also confirm this, as it was often observed that,
although the small crawfish could by their superior agility,
and apparently keener sensory organs, first detect the bait
and make off with it, yet they were no match for the heavier
and stronger adults in the struggle for possession of food.
19
The smallest male (13 inches) was procured from Woodstock
Beach at 5 fathoms of water. The largest (74 inches) were
procured at Robben Island at 13 fathoms and at Woodstock
Beach at 5—2}4 fathoms. The total number of males procured
at the different sizes mentioned in the tables were as follows :—
Sizesininches. I+ 2+ 3+ 4+ 5+ 6+ 7+ 8+
(I) - AZ) AF Oe FAB AO
(2) gS ctr WG mee UOTE 27s. Sy feral
(3) 25,9 Sere OU RS
(4) - 4 2
(5) 363 G | : eS a
(6) Ae RAP AneeyS
(8) (3) = 200) ss Tee Eas
(9) Mat 2a
(10) 5 Gate ae 3
(11) SiS ee ig
(14) ne I i6
(15) . a
(16) 2 lie 8
(18) PAGS cole te A
(20) ae 17, ape
(21) er a 2
(22) se Ae es
25 823) eran r2as 78 | TAGs a3
The largest number of males were those between 5 and 6
inches, though not much in excess of those between 6 and 7
inches, and a fair number were over 7 inches.
If these catches are representative, therefore, the protection
of males under 4 inches would be no great burden on the
industry.
- The average size of all the males procured was 4:9 inches,
of the females 3-8 inches.
Females.
In the three visits to the deeper waters off Robben Island,
females were absent, with the exception of the third, in which
3 adult females in hard shell were procured.
The hauls in the shallower waters off Woodstock Beach
showed that the females were abundant there, and were in
berry at this time (November). That this is a normal occur-
rence is well known to fishermen who, during the close season
when the crawfish is only allowed to be taken for bait, often
procure these berried females, as they are within easier reach
in the shallow waters near Woodstock Beach than are the
[ese es 13
ZO
males in the deeper water further outside the Bay. From
the returns it will be observed that all the females above 3
inches procured in the first hauls (12th and 28th November ;
12th, 17th, and 30th December ; 7th, roth, and 21st January)
were in berry. Those in hard old shell (12th November, 12th
December, 17th December) were under 3 inches or, if larger,
were in deeper waters near Robben Island (13th November).
On the 28th January and again on the 4th February large
males were got, but no females.
On the 6th, r4th and 24th February the neighbourhood of
Hout Bay was visited, and only large males and females (with-
out eggs) were got. This locality is said to be somewhat
earlier than Table Bay, but no valid conclusion can be drawn
from these few hauls.
The tables throw some light on the much-discussed question
of the size at maturity of the female. This can best be shown
by the following tables of size and numbers of berried females :—
Size in inches .. T+ 2+ 3+ 44+ 5+ 6+ 9+ 84
Hauls INO: +3.) ov he “et eZ
ga Nios 5 . St eens
mt wNOz 7 2 I
aS NO4 7S. 6 :
55 No. 9 Ti
ee No: tO 19 2
PIN err 2 I
np NOuee? 2 5
3
Os 472. 35), a
From this it is seen that the smallest female in berry was
between 2 and 3 inches. Berried females between 3 and 4
inches were by far the most abundant, and there was a rapid
falling off above 4 inches, there being only 13 between 4 and 5
inches, 3 between 5 and 6 inches, and none above 6 inches.
No females of any kind, in berry or not, were procured above
this last size, though several males were procured over 6 inches..
21
Closer details of this may be shown by considering the actual
measurements of the berried females. These are shown in
the following table and curve:
Nees. Date 1) IS LEVEY
haul
3 12.41.12
Gain.
| 12.4212,
2.1212
30/212
8.113
essere
© ~NUEGQAYH OG SHAE GAB
{| {|
From this}it will be observed that the number of berried
females rapidly increases up to 3}¥inches and as rapidly
decreases beyond that size. Beyond 4 inches there is again
a rapid drop, there being very few females in berry of a larger
size. The present legal size limit of 3 inches falls just before
the size of greatest fertility according to these figures. It
represents 32 inches in the method of measurement here adopted
and is represented by the asterisk in the diagram. To ensure
adequate protection of the female, the size limit should be
increased to 44 or 44 inches.
From the data given above, the condition of the female
may be noted at‘different seasons, though only very generally,
as the data are#not}sufficient. In November, I1 berried
females were got on two occasions. In December, 14 on
three occasions. In January, 31 on three occasions. The
largest number were got about the beginning of January, and
none after the 22nd January, which may therefore be pro-
visionally taken as the end of the spawning season.
We may note also that the smallest crawfish in berry was
24 inches, procured on the 12th January off Woodstock Beach
in 54 fathoms of water and that such small forms were very rare.
The largest female was 5 inches, there being only 3 of this
size, t from Woodstock Beach from 4 fathoms, 28th Novem-
ber, and 2 from the same place from 5 fathoms on the 12th
December.
[(C.P. 5—'13.]
NO
to
3. OBSERVATIONS AT THE MARINE LABORATORY AT ST. JAMES
TO DETERMINE THE BREEDING HABITS, ETC., OF THE
CRAWFISH.
About the beginning of October, 1906, four females were
procured from Saldanha Bay and placed in the tanks of the
Marine Station at St. James. They were obtained in the
course of an enquiry to determine the smallest size of mature
females carrying eggs with a view to the fixing of a size limit.
After about two hours’ fishing, the fishermen, who knew at
once in what locality females in berry could be caught at
that time, were able to procure ample material in the form
of a full boat-load, all females in berry. There were about
600 in all and were from near the mouth of the Bay. Four
of the smallest of these were selected, all being about the
same size, namely, 3} inches in length of carapace. These may
be designated A, B, etc., and there subsequent history was as
follows :—
Female A.—On the 15th October, 1906, the eggs hatched
out and produced numerous larve. On the 28th April of the
following year (1907) the crawfish cast its shell, and again on
the 4th July of the same year. About the 18th and roth it
was attended by two males, which had been placed in the tank,
and on the 20th it was observed to be carrying a full mass
of eggs below the tail, copulation and the extrusion of eggs,
as in nearly all other cases, having taken place during the
night. The two males about this time were very pugnacious,
the larger driving off the smaller. After the extrusion of the
eggs, the larger male returned to his customary place in the
tank, though keeping a watchful eye on the other male. At
times he resumed his attacks on his rival, driving him off to
remote corners of the tank, and even then occasionally renew-
ing his hostilities. It was not until, by accident or superior
intelligence, the smaller male was able to reach a stone sus-
pended in the tank that he was left in peace, the larger male,
in spite of repeated attempts to reach him, being unable to
do so. Thereafter the larger male was left in undisputed
possession of the females. It would appear, therefore, that
the animal is polygamous in its habits, a fact of importance
in restrictive measures which may be adopted to regulate
the industry.
The eggs were shed about the 5th October, 1907. On the
29th of May of the following year (1908) the shell was again
cast, and on the 6th July the crawfish was again carrying
eggs externally ; these were shed on the 18th of September.
2
o>)
On the 29th May, 1909, and again on the 21st October of
the same year, the shell was cast, but there were no eggs
during the whole of this year.
In rgr0 the shell was cast on the 27th May, and again on
the 11th August. On the 25th of the same month copulation
was observed with a male, and on the 26th the female was
observed to be carrying eggs. These were of a pale whitish
colour, but in a few days acquired a yellowish tinge. About
the beginning of October the eggs were cast off from the
abdominal appendages, and by the 8th only a few were left.
On the 8th July, ror1, the shell was again cast.
Female B shed eggs about the middle of October, 1906,
cast shell 16th April, 1907, and was carrying eggs some time
before the 2nd June (the first of the four to have eggs again).
It cast its shell again on the 26th October with the eggs still
attached, an entirely abnormal occurrence. On the oth June,
1908, the shell was again cast. The animal died on the 2oth.
Female C shed eggs about the middle of October, 1906,
cast shell 28th April, 1907, had eggs about 15th June, 1907,
and shed eggs 25th October, 1907 ; cast shell 2nd June, 1908,
and had eggs shortly afterwards. Cast shell 7th June, 1909,
but had no eggs that year. Cast shell 3rd June, 1910, and
had eggs shortly afterwards, being attended by male some
days before. On 19th June, rgr0, cast shell.
Female D shed eggs about middle of October, 1906, cast
shell 7th June, 1907, attended by male 22nd June, 1907, and
had eggs on the 24th. By the 25th October all eggs were
shed. On the 26th May, 1908, cast shell, and had eggs. On
the 29th June, 1909, cast shell, and had no eggs this year.
In drawing any conclusions from these experiments allow-
ance must of course be made for the more or less unnatural
conditions under which the animals lived (in the confined space
of the aquarium tanks). That this had some influence,
though the animals themselves were apparently quite normal,
is shown by the fact that in all but the first year the ova did
not develop normally and no larve hatched out.
Several important conclusions may, however, be drawn—tor
instance, that the females cast their shell about mid-winter,
that soon after casting their shell and while still soft they are
fertilised by the male and almost at once extrude the eggs,
which are carried externally for about five months. The date
of the casting of the shell in the females may therefore be taken
as at the beginning of the spawning time.
The dates of the casting of the shell in the case of the four
individuals are shown more clearly in the following table :—
[@ Bas 13;|
24
Dates of casting of shell in four females from Saldanha Bay :
x B. C D.
( 8th April fr6th April 28th April 7th June.
BOY Atha July { 26th September.
1908 29th May. oth’ June. (2znd7\une. 26th May.
(died.)
28th May. athe | ume: 29th June.
a0? | 21st October. ‘ :
a ae! 27th May. ard June; r2th July.
9 \ 11th August. (Died casting
shell.)
Ig1r 8th July. roth June.
The question as to how often crawfish cast thetr shell has not
yet been investigated. Judging from the analogy of the
European lobster, whose life history is now well known, this
would occur several times a year in the young and, as a rule,
once a year in the adults. In the above table we note that
A (go mm. in length of carapace) cast its shell twice a year
with the exception of two years (1908 and 1911); C (104 mm.
in length and presumably older) cast its shell only once a
year throughout the five years, and at very regular intervals,
with the exception of the first (1907).
The t2me of casting of the shell is mostly in the month of
June, but may be from April to October. This last date was
observed in the case of A in 1909, and is probably very excep-
tional, and perhaps connected with the fact that in this year
there was no spawning.
The time of sbawning—that is, the time of the extrusion
of the eggs from the body—was, as a rule, some days after the
casting of the shell. In cases in which the shell was cast
twice in the year it was after the second casting. In these
cases also it is noted that the spawning season is later. Thus
in specimen A, in which the shell was shed twice a year,
spawning took place in July and August (20th July, 1907;
6th July, 1908; 26th August, 1910), while in specimen C,
which only moulted once a year, spawning took place in June
as a rule (15th June, 1907; 23rd June, 1908; 28th June,
1910; 11th July, 191r). Specimen C was older than A, and
it may be concluded, as far at least at these two cases are
concerned, that spawning is later in the younger specimen.
With regard to the frequency of spawning, this appears to
be not more than once a year, and this was so even in the case
in which the shell was cast twice in the year, namely, after
the secynd moult. It has for long been a disputed point as
ac
2)
to whether or not the lobster of the northern hemisphere lays
her eggs only once in two years, and, while it is still not abso-
lutely accepted, there seems to be very conclusive evidence
that this is so. In the case of the crawfish, our experiments
seem to indicate that this may take place every year; but it
is to be noted that none of the females had eggs in one year
(1909). It may be, therefore, that the frequency of spawning
js more than once in two years and yet less than every year.
With regard to the time of casting of shell of the male, among
the specimens (from Table Bay) kept in the tanks, this was in
October and September.
The rate of growth or age of the Cape Crawfish is a matter
which has not yet been investigated. Judging from the
experiments at the Marine Station, St. James, the increase in
size is not rapid and is unequal. In the case of Female A it
was I°5 mm. in 1907, the same in 1908, but 6 mm. in 1909
(the year in which no eggs were laid), and 2 mm. in 1910.
4. GEOGRAPHICAL DISTRIBUTION OF CAPE CRAWFISH.
The Cape Crawfish has a peculiar distribution, being confined
to the West Coast so far, at least, as practical fishery purposes
are concerned. A few were found as far East as Bird Islands,
on the East Coast, during the trawling operations of the Pzeter
Faure. These were, however, of a small size, though specifi-
cally identical with the crawfish found so abundantly near
Cape Town. Its place is taken in Natal by. other and quite
different kinds, which occur in no great abundance, chiefly
amongst the rocks of the shore. It is found also at Hermanus,
the specimens got at this locality being also of a small size.
In False Bay it is occasionally met with, but so seldom that its
capture is somewhat of a rarity. On rounding Cape Point
and coming into the colder waters of the Atlantic it is found
in great abundance, as for instance at the Kommetje, only
a few miles from False Bay. From this point northwards it
is very plentiful. How far north it extends has not been
recorded, but it was found in abundance by the Pzeter Faure
as far north as Mercury Island.
Doubtless the distribution is determined directly or in-
directly by the great difference in the character of the water
of the West Coast northwards of Cape Point from that of
the East and South Coast, the former, originating in the
Antarctic Circle, being of a much lower temperature and
specific gravity than the latter, which comes from the tropical
regions of the Indian Ocean, and is of a higher temperature
and specific gravity. This distribution is not peculiar to the
[C.P. 5—’13.]
26
crawfish, but extends to many other marine invertebrates as
well as fishes, as, for instance, the snoek. Some years ago
some enterprising citizens of East London thought to remedy
this unequal distribution of the gifts of Providence by import-
ing a shipload of crawfish from Cape Town. The consignment
arrived safely, and was placed in a suitable locality, but
apparently the fish did not thrive, as they were never again
seen.
There have been suggestions from time to time of the
advisability of transporting a number of crawfish from Table
Bay to False Bay, where they might breed and multiply.
This seems a more feasible proposition than that just men-
tioned, but, for the reasons stated above, the success of the
experiment is highly improbable.
The fact that the Cape Crawfish as a commercial asset has this
comparatively limited range renders wt all the more probable that
the supply may be affected by indiscrinunate fishing, and the more
necessary that adequate means be taken for its preservation.
5. SEXUAL DIFFERENCES IN THE CRAWFISH.
The difference between the male and female crawfish are at
first sight not very striking, and this is of importance in
connection with the practical difficulties in carrying out any
legislative measures for the protection of the female.
The differences are chiefly the following :—
(1) The female is, as a rule, smaller than the male, and is
never much over 4 inches in length measured from the base of
the eye-stalk to the end of the carapace. Individual specimens
have been known to measure between 5 and 6 inches, but
these are exceptional. It follows from this that a size limit of
4 inches would form a very effective measure for the protec-
tion of the female, which, we will see when dealing with this
question, is a very vital point in the protection of the industry.
(2) The female, as a rule, seems to differ in colour from
the male, being generally somewhat darker.
(3) There is a difference in the relative breadth of the
carapace, this being decidedly greater in the male.
(4) The tail shows marked differences, connected with the
important function of carrying the eggs. Thus, in the female
it is broader throughout its length than in the male, as will be
shown by the following measurements (in millimeters) of the
length and breadth of the carapace and the breadth of the several
tail segments of three male and three female specimens :—
Carapace. Tail Segments.
aes : g
3p 3 ¥ 5 BS = <|s
a oO an rs) = =| + 2
cB) = | oO pe} ° = a
4 ea) oa n cal fy — op)
Females Bac 127 | 85 73 | 80 83 | 80 76 | 72
Mean! * | 113 76 | O4th 2 Vs 7a || 72" 68) 1 64
Males ..+/ 83| 59| 43) 44| 43| 42] 43 | 43
Mean 720 | #842)" 25G | 6x | 60/ 59) 59 59
The relative breadth of carapace and of tail segments in the
male and female may be more clearly shown by expressing
them in the number of times they were contained in the
length of the carapace, thus :—
Measurements in length of carapace.
Female a I | IAG |e FOS 7. | E521 1°57 166 1°76
INANE? Ms) sas I | I°43 | 2°03 | 1°96| 2°00 | 2°03| 2°03) 2°03
Difference in fa- | | | | |
vour of female] 0 | +°05| —'27| —"39| —48| —46| —37 \—'27
These figures show that the breadth of the carapace is
contained 1-48 times in its length in the case of the female
and 1-43 in the case of the male: that is, that the carapace
of the female is relatively narrower than that of the male.
In the case of the first segment its breadth is contained in
the length of the carapace 1-76 times in the female and 2-03
in the male, a difference of -27. This first segment is, there-
fore, narrower in the male and this is true also of the succeeding
segments, the relative difference being expressed by the figures
39, 48, 46, 37, 27. This may be expressed in another and more
direct way by taking the length of the carapace as 100 and
[C.P. 5—’13.] D
28
expressing the breadth of the carapace and tail segments in
proportion, thus :—
|
Female, - 9100 67 | 56 | 63") 65.) 637)" "600/56
Male, aEOO 670"! 41") S500 50 | 49 | 49| 49
Difference in fa- | | |
vour of female o b $3 }+I5 |) +13 | +15 | +14 | +11 | +7
|
Thus in a crawfish whose carapace measures 100 mm. (from
the tip of the rostrum to the posterior border of the carapace)
the carapace is 3 mm. narrower in the female, and the tail
15 mm. broader in the first and third segments, 13 in the
second, 14 in the fifth, 11 in the fifth, and 7 in the sixth. A
female and a male of equal length of carapace are therefore
readily distinguished as there is a difference of 15 mm. in
the greatest breadth of the tail. This is enough to be readily
detected on a mere glance at the fish.
(5) Though the carapace is narrower as measured by its
greatest breadth, the under side or sternum between the last
pair of walking legs is broader in the female than in the male.
This difference is well marked and is quite evident when
pointed out. Thus, in the third female in the tables (115 mm.
in length) the breadth of the sternum as measured by the
distances between the points of articulation of the five pairs
of walking legs were, as compared with those of the third male,
(measuring 122 mm. in length) as follows :—
Distance between walking legs.
Length of
Carapace. |
First | Second | Third Fourth | Fifth
| | |
Male .. 122 13 27 38 42°5 | 26
Female 115 ET 24 23 4i 2a eee
or taking the length of carapace as 100:
Male ..' 100 TO i) 2250 -l\ wean uh See Ne ore
Female | 100 Or) 29" Pas 28 350) | B27
29
The distinctly greater width between the bases of the last
pair of walking legs in the case of the female is therefore a
characteristic and easily-recognised feature, being 27 mm. in
the female as compared with 11 in the male of a crawfish oo
mm. in length of carapace.
(6) Another marked difference between male and female
crawfish, though not recognised without closer examination,
is in the position of the genital openings, these being at the
base of the last pair of walking legs in the male, while they are
at the bases of the third pair in the female.
(7) Finally, there is a well-marked structural feature in the
female not found in the male. This is a small pair of pincer-
like claws (chelae) found at the end of the fifth pair of walking
legs. These are not used for seizing prey, as is the case in the
large claws of the lobster, but are used for arranging, cleaning
and aerating the eggs.
The points of external difference between male and female
are, therefore, numerous and well marked when analysed,
and although they may not be apparent to a casual observer,
are readily recognised by the experienced fishermen, so that,
though he may not be able to express these differences specifi-
cally, he can pick out readily enough the males from the
females in any lot of fish.
6. EARLY STAGES OF THE CRAWFISH.
The various stages through which the crawfish passes after
hatching from the egg have been investigated at the Marine
Laboratory at St. James and by tow-nettings in and near
Table Bay. The eggs have hatched out satisfactorily and
some of the larval stages have been noted, while larve of about
the same and older stages have been found in the sea. Three,
or perhaps four, more or less distinct stages have been noted
in all, but there are many gaps between these and the adult
form, and it will be the object of further investigation to find
these. On the results of such investigation will depend the
feasibility of artificial hatching and rearing.
The following short summary, however, may be given of
the results so far obtained.
There emerges from the egg a small form entirely unlike the
adult.* Plate I shows the general appearance of the larva (en-
larged about 84 times) in the living condition. The body
is rounded or ovate and still contains some of the yellow
yolk granules of the egg stage. The antennae are at
this stage well developed. They have two branches and
these are provided with long projecting setae. By means
of these the animal swims about, rising first to the surface of
* \ more detailed description of this larval form has been published in the
Journal of the Linnwan Society, London.
[(C.P, 5—’13.]
30
the water. These are the only active locomotary appendages
at this stage, all the others being more or less folded up under
the body. The first two pairs of walking legs are branched,
but the outer branch, though segmented, is not yet provided
with swimming setae as in the next stage, and the inner branch
is folded in itself. The last two pairs of walking legs are
awanting.
When this larva moults it undergoes considerable change.
The swimming setae of the antennae are thrown off and these
appendages no longer perform the function of locomotion.
This is now performed by the outer branch of the first two
walking legs. Hitherto this has been a simple rounded organ,
but on the shedding of the cuticle it expands into a feather-
like structure with lateral projections or setae, which again
are provided with smaller sete, so that the whole forms an
effective instrument for swimming purposes as the three walk-
ing legs, instead of being folded up under the body as in the
previous stage, are now widely expanded. A change has
taken place, too, in the body, which is no longer opaque, but
is glassy and transparent, This stage (the typical ‘ phyllo-
soma ’’) has been procured in the aquarium at St. James and
also by means of fine nets in Table Bay.
A single specimen has been found at a more advanced stage
in which the third pair of walking legs has acquired a swimming
outer branch and a fourth leg with the rudiments of the fifth
pair appears.
Amongst other phyllosomas found in townettings a larger
form (33 mm. in length) appears to be a still later stage of the
crawfish. Fuller results of these investigations will be published
with figures at a later date, when more data may be procured
7. HABITS OF THE LARVAL CRAWFISH.
On hatching, the young crawfish in the first free stage casts
off the cuticle of the previous stage. This cuticle may be
seen lying alongside or partly protruding from the ruptured
egg capsule. The large swimming antenne are at once spread
out, and apparently the larve cling to the surrounding eggs,
or are retained in some way in their midst, until shaken off
by the vigorous movement of the tail of the parent.
The larva then rises quickly to the surface by a series of
rapid movements in a vertical direction. This is accomplished
by the up and down movement of the antennz with their long
sete. The exopodite projects towards the dorsal side of the
animal, the endopodite being in the same plane but projecting
laterally. The large wing-like or rather parachute-like struc-
ture formed by the rays is so constructed that, on the downward
31
stroke of the antenne, they expand widely, and drive the’
animal upwards, while, on the upward stroke, they bénd
downwards at their tips and the body is only carried slightly
lower. The final result is that the larva is carried upwards
by a series of dancing movements (about 4 per second), which
are continued with short periods of rest till the animal reaches
the surface of the water.
The factor which determines the direction of movement
is apparently the light, and once at the surface they rapidly
congregate towards the most illuminated corner of the tank.
The rapidity with which they seek the light, and their power
of discriminating between slight differences in illumination,
were well illustrated by placing several in a glass dish in a
room with two windows having slightly different outlooks.
They quickly approached the more illuminated side, and, on
this source of light being lessened, they as quickly moved
towards the other source of illumination. In this lateral
movement the main axis of the body is, of course, more or
less changed in position.
Should movement cease for a short time in the ascent, the
body sinks rapidly, as it is still laden with a certain amount
of heavy yolk, lodged in the region of the large diverticula of
the future liver, the anterior end of the alimentary tract and
the thinner intestine. This yolk is apparently sufficient to
tide over the interval between the first and second moult.
Under the microscope the mouth appendages are seen to be
in active movement, but their spines and denticulations
are as yet covered by cuticle, and apparently the animal takes
no food at this stage.
The duration of this stage is very short. A number ‘of
individuals on one occasion was observed given off from the
parent in the morning and, by midday, they had all changed
into the second stage.
The significance of this larval stage, of so short duration,
and in which the animal may take no food, is doubtless con-
nected with that fact that the larva changes into a second
stage which procures its food at the surface of the water,
and which is so organised that an upward movement is not
easy. Though the duration of the first stage is only for a
few hours, it is sufficiently long to enable the larva to ascend
the few fathoms of water in which the parent lives.
In the second stage the legs become expanded and hang
down on each side of the body, all except the last pair (the
third walking leg) which are long and are trailed out behind.
The body now assumes a horizontal position and progression
is mostly parallel to and near the surface of the water. The
[C.P. 5—'13.]
32
first and second walking legs hanging downwards ready to
seize any food particle, draw it up to the body and hand it
on to the maxilippedes maxilla and mandibles, where it is
crushed and mixed up before passing on to the stomach.
The upper and lower lips are in active motion, they cover
over the mandibles, thus forming a sort of cavity analogous to
the ‘*‘ gastric mill” or grinding stomach of the adult.
The temporary outer branches of the second and third
walking legs function as very active swimming legs in such a
way as to direct the body forward. They do not appear to
be at all directive.
The animal, however, is able to turn quickly, even to swim
in short somersaults by means of the bending of the long
rudder-like hind limbs (third walking legs). The body can
also be rotated on its long axis by the movement of these
limbs, as they are rather widely directed away from each
other posteriorly.
This stage, like the first, swims rapidly towards the light.
After about four days the larvee were observed to be more
scattered throughout the tank, often at a distance from the
surface. On one or two occasions they were observed to
descend to the floor of the tank and rise again. At other
times they kept to the margin of the tank, where a number
of copepods and small crustacea occurred, but, although
these animals kept clear of the young crawfish, there was no
attempt on the part of the latter to seize them.
About the fifth or sixth day the larve gradually disappeared.
For better observation one was removed from the tank and
placed in a bell jar containing clean sea water, which was
renewed from time to time. This larvee was very active,
swimming about by vigorous movements of its swimming legs,
though progression was in no case very rapid. Occasionally,
however, there was a rapid turning movement ventrally,
apparently for the purpose of seizing floating particles. About
the seventh day the young crawfish was observed to be
keeping almost exclusively to the bottom of the jar, occa-
sionally examining small particles of debris, though a small
quantity of boiled yolk of egg placed in the jar was apparently
not touched. It was then observed that the animal had so
changed its habits that it now avoided the light, instead of
seeking it, and it could now be made to move from side to
side of the tank, as in the case already mentioned, but in the
opposite direction, keeping as far removed as possible from
the source of light. The movement, however, was not so
marked as in the previous stage. As this fact may prove of
importance in elucidating the life history of the animal, the
33
experiment was repeated several times, so that there was no
doubt about the actual fact. Provided that this was not
brought about by the artificial surroundings or condition of
the larve, it would seem to point to the reason why so few
phyllosomas were found in townettings as they might have
retreated to the darker or more shady parts.
It is to be noted that the crawfish in the swimming stage
did not exhibit any great timidity in its movements but
moved about rather slowly and apparently fearlessly. Most
small crustaceans dart away rapidly on the approach of
suspected danger, but these forms only moved off slowly, on
being threatened by any object suddenly brought near them.
8. AGE, RATE OF GROWTH, ETC., OF CRAWFISH.
Very little is known with regard to this subject. The
first free swimming stage, after hatching, lasts only a few
hours as has been recorded, but how long the second stage
lasts, and how many changes take place before the ground
form is assumed is not known. This is of importance with
regard to the question of the possibility of artificial rearing
of the fish, and indicates a direction for future investigation
of economic importance.
At what size or age the female reproduces is also of im-
portance. If one can rely on statements of various observers
this occurs at a very small size. Unfortunately these state-
ments may be consciously or unconsciously influenced by
ulterior considerations, and they have never been confirmed
by producing the actual specimen. The smallest female
carrying eggs which I have been able to procure was much
larger than the sizes stated, and measured 2} inches in length
of carapace.
The size of the largest female is of even greater importance.
It is stated that at Hoetjes Bay Factory they have been got
up to 54 inches, though very seldom, and always in deep
water—perhaps such large specimens are old and past breeding.
A female of between 5 and 6 inches has also been got at Hout
Bay Factory, but this was considered a giant and very ex-
ceptional. As a rule, females do not usually much exceed
4 inches in length of carapace.
Males, on the other hand, grow to a much larger size, and
have been seen about g inches in length of carapace. That
these are probably very old males is indicated by the fact
that they are generally covered with various growths, especially
hydrozoa, which give them a hairy appearance—hence the
idea among fishermen that old males grow hairs. The presence
of these growths on the shell probably indicate old age, as,
at this time of life the shell is not shed so frequently, if at all.
[C.P. 5—’13.]
34
The bodies of these large fish are also not so well filled with
“meat ”’ it is stated by fishermen.
The usual size of males of the best marketable value is
between this size down to about 3} or 4 inches. Smaller
fish are not so useful at least for canning purposes.
It is not known as yet what relation exists between the
age and size of the crawfish, and it may be useful to note
that in the lobster of the Northern Hemisphere it has been
found that those between 2 and 3 inches in total length may
be considered to be about one year old, those about ro inches
four and a half to five years old.
g. ENEMIES OF THE CRAWFISH.
In considering any measures for the protection of the
crawfish it is necessary to have some knowledge of what
other enemies besides mankind the animal has. Thus, for
instance, the Octopus is a serious enemy of the crawfish,
when in its youngest crawling stages, and if one octopus
devours a hundred young crawfish to one caught by fishermen
there is not the amount of protection afforded to the animal
as one would at first sight suppose by the prohibition of the
catching of small crawfish. And from actual observation of
the behaviour of the animals in the tanks of the Marine Station
at St. James’ there seems to be reason for believing that this
is what actually happens. There it was observed that the
healthy adult was well able to protect itself against the attacks
of the octopus by means of its long antenne, which are pro-
vided with strong and numerous spines, the points of which
are directed forwards. On the approach of an enemy these
tentacles are quickly brought forward, and, on contact with
them, neither fish nor octopus care to advance further. It
was only in the case of a “‘ soft ’’ crawfish (one which had just
cast its shell) or a sickly one that the octopus was able to
successfully attack its prey. It was different, however, with
the small crawfish, which, like crabs and other small crus-
taceans, seem to constitute the chief source of food supply
for the octopus. If it be borne in mind that every rocky
coast is inhabited by numerous representatives of the octopus
tribe, and that these are constantly searching every nook
and cranny with their long arms for the small crustaceans on
which they feed, it will be realized that the chief mortality
in crawfish life probably occurs at the early rock frequenting
stage. Reference is here made of course only to the very
young crawfish, up to about 2 inches in length of carapace.
There are many thousands of octopus to one fishermen engaged
in the capture of these small crawfish, and the methods of
35
fishing is at any rate as effective in the case of the first ren-
tioned, so that it is doubtful at least if the prohibition of the
fisherman’s operations really afford any material protection. It
is different of course when the crawfish is large enough to escape
the octopus. Another serious enemy of the young crawfish
at this early stage of life is probably the ‘‘ horse-fish ”’
(Agriopus), which seems to live chiefly on small crustacea’
about the size of these small forms. This large toothless
fish can extract crabs, etc., from their hiding places by the
sudden protrusion of the mouth parts, which form a powerful
suction tube.
The so-called “‘sea-snake ” (Bdellostoma) is said by some
to attack the crawfish. It is frequently found along with
the crawfish in the fishermen’s nets and certainly devours
dead crawfish. It is the experience, however, of most fishermen
that it is not a serious enemy of the crawfish, if one at all.
Certainly there was no disposition observed on the part of
these “snakes” to attack live crawfish when kept together
in the same tanks at the Marine Laboratory at St. James’.
Some of the more adventurous of the young crawfish indeed
attacked these animals when first placed in the tanks with
them. They were, however, very soon disconcerted by the
slimy matter given out by the “snakes,” and, in fact, had
some difficulty in getting rid of it, as it clung to their tentacles
and body and caused them great trouble for some time after
their ill considered attack. The presence of the sea-snakes in
the crawfish nets is therefore doubtless due to their being
attracted by the fish bait.
Fish generally do not seem to be serious enemies of the
crawfish. In the tanks they usually avoided it, and, when
they happened to approach too closely, they at once started
off as soon as they came in contact with the long spiny
tentacles, which were thrust out in their direction.
Amongst sea birds the “ Bank Duiker » (Phalacrocorax) 1s
said to attack and devour crawfish.
While the adult crawfish is thus well provided with means
of defence, it is different when the shell is cast and the animal
is at the mercy of most of the other sea animals. It is then
very wary and conceals itself as much as possible amongst
rocks or in sand. It employs the same means of defence
however, when approached, bringing forward its tentacles
and keeping them projected towards the source of danger
Of course they are then quite soft and flexible though in
appearance in their normal condition. Apparently this
is undetected by some of their enemies, as theyohave been
observed to rapidly move off on the approach of the threaten-
[C.P. 5—’13.]
30
ing though harmless tentacles. Dogfish readily attack the
soft crawfish, however, as has been observed in the tanks, and
is evident from the fact that the soft shells of crawfish have
been found in the stomachs of these fish. The octopus also
is not deceived by the apparently unchanged shell. Even a
very small octopus has been observed in the tanks to attack
a large soft crawfish and secure one of the large legs, of which
it made a meal. Small crawfish also have been observed to
attack and demolish large soft crawfish.
Apparently, however, man is the most serious enemy of the
crawfish in its adult stage, and this would be sufficient to
account for the rapid diminution in the supply, experienced
as the result of the extensive operations of the factories.
These adults occur in enormous numbers, and it was at first
supposed that no fishing operations could dangerously affect
the industry, but the explanation at once of their large numbers
and the effect of fishing is probably to be found in the fact
that they have comparatively few enemies in the adult stage.
Another fact tends to confirm this, namely, that formerly,
before this extensive fishing, very large old crawfish were
frequently found, and these no longer or seldom occur in the
nets of the fishermen, though still readily procurable in fishing
grounds somewhat remote from those of the usual fishing
operations as, for instance, at Dassen Island.
The following figures supplied by one of the Crawfish fac-
tories of the percentage of small and middle sized fish during
four years, 1909-1911. afford more definite evidence pointing in
the same direction : 35 per cent., 40 per cent., 40 per cent., 50
per cent.
There are, however, other stages previous to the early ground
stage and the adult stage, as will be seen in the account of the
life history of the crawfish. The egg stage, when carried about
by the female, is not immune from hostile attacks. The eggs
are very carefully guarded by the female, and they may be
quite covered up by the strong flexure of the tail, but, from
observation in captivity, it was seen that several small fish, such
as Klip-fish, but particularly small Dasjes, are very fond of
the eggs and take every opportunity of harassing the female ;
darting under the tail, they frequently secure two or three,
and their success leads to repeated attempts.
In some of the townettings made in Table Bay there was
found a considerable number of unhatched but well-advanced
eggs of crawfish. Whether or not this indicates that in nature
the eggs may be prematurely detached or, what is more likely,
that the females have been attacked for the sake of their eggs,
which are thus scattered about, is not yet known. The fact
37
that these eggs were found in this way seems to indicate that
there is some agent of destruction at this stage, for probably,
these eggs when they sink to the bottom of mud or sand
could not hatch out.
The larva which is hatched out from the eggs seem to be
much more liable to attacks of enemies, perhaps on account of
the presence of the unconsumed yolk granules. By way of ex-
periment some eggs and larvee, some hatching and some just
hatched, were put into a tank containing harders (mullet) and
were at once attacked and devoured. In one case two or
three female crawfish were kept in a large tank with several
kinds of fish, and it was repeatedly observed that small fish,
more especially Klip-fish (various species of Clinus), were con-
continually on the watch during the hatching time, hovering
round the female and devouring many of the larve as they
were shaken off.
On the other hand, the larvee when past their first stage
and dispersed in the water do not seem to suffer from the
attacks of fish. Thus when a few active transparent larve
were placed in this tank they seemed to completely escape
the notice of the fish or at least were unmolested. Two or
three small gobies in the crawfish tank remained quite in-
different even when the larve scattered in hundreds through-
out the tank almost touched their snouts. As noted under
habits of the young crawfish at this stage, their behaviour also
seem to indicate that they had little cause to fear the
presence of enemies.
To sum up, the crawfish produces many thousands of eggs
which may be devoured by fish. The early larvee (still opaque)
and eggs which are shaken off in clouds by the female are
specially liable to attack and are probably destroyed in large
numbers. At a later stage when the larve, now transparent,
are widely scattered throughout the water, they would appear
to be comparatively immune from attacks. At a later stage,
however, when the larve take to the bottom, and become
opaque and pigmented, they are again liable to the attacks
of their enemies, notably the octopus.
Lastly, the adult stage seems again to be better able to
defend itself and to have comparatively few enemies with the
exception of man. For the depredations of the fish and the
octopus nature has made provision by producing a surplus
of progeny for these natural enemies, and on the whole the
crawfish can maintain its own, but it has made no provision
for the depredations of man at a stage when fewer natural
enemies are present. Hence it is that this new drain in the
supply so quickly upsets the balance, and, in spite of the
[C.P. 5—13.]
38
abundance of the adult forms, continual and extensive fishing
operations very soon affect the supply.
10. FooD OF THE CRAWFISH.
From observations made on the crawfish in captivity, its food
seems to consist chiefly of any kind of animal matter that may
happen to be present, such as dead fish, etc., and they act as
scavengers in the life of the sea. They readily attack any
disabled fish, but are quite incapable of doing any harm to a
healthy normal specimen. They have frequently been ob-
served to make sudden and rather clumsy attacks on resting
fish, but these had no difficulty in escaping. It is stated by
some that they live to a large extent on soles, and the sugges-
tion has been made that the fewer crawfish the greater will be
the supply of soles, so that the diminution of the crawfish
supply is not without its compensation. This is founded
chiefly, I believe, on the fact that crawfish are sometimes
found in the fishermen’s nets with a fresh sole tightly grasped
in their legs. From what I have seen of the habits of the
crawfish, however, this would appear to be the result of the
special opportunities for the seizing of the sole in the narrow
confines of the net in which both are captured. This plea,
therefore, for the extermination of the crawfish can scarcely
be justified and, in any case, is beside the point, as the regular
habitat of the soles of commerce is in a region far removed
from the haunts of the crawfish—a fact which, however, might
be looked upon as a confirmation of the first position.
The stomachs of the captured crawfish frequently contain
a substance like finely broken-up shells and they doubtless
live to a large extent on various molluscs they find in the
mud. In captivity they seldom pay any attention to such
animals, but, on one or two occasions, they were observed to
attack fairly large and strong shells, as, for instance, that of
Turbo. The shell was taken up in the claws and turned round
so that the edge could be firmly grasped between the powerful
mandibles of the crawfish. The shell was then twisted to the
side by the legs and the piece grasped by the mandibles broken
off. The shell was so thick and strong that the noise of the
breaking could be distinctly heard through the water and
sides of the tank. This process was repeated until all the free
edge of the shell was broken off, down to the very solid oper-
culum, which was of course strongly drawn into the opening
of the shell during the process. Further progress was more
difficult, but, by inserting the sharp claws between the exposed
operculum and the shell, the contents were finally exposed.
39
Crawfish have been observed in the tanks making
attacks on sea urchins, but with little success. The animal
was taken up in the claws of the crawfish as in the case of the
Turbo, and the spines were bitten off one by one by means of the
mandibles till the whole shell was quite bare. All attempts to
penetrate the shell or the oral or aboral areas were, however,
in vain, and the crawfish finally abandons its prey, which
then fell a victim to the omnivorous starfish, which is
provided with other and more effective means of attack,
provided the spines are removed.
As regards food supply, the crawfish is very easily kept
in captivity. It can survive for long intervals without food,
and can be fed continuously on the same kind of food. It
was never observed to feed on vegetable matter, though that
it does so is shown by the stomach contents of captured fish.
tr. MIGRATION AND MOVEMENTS OF THE CRAWFISH.
Information is wanted on this subject in connection with
the alleged difference in the spawning times of the crawfish at
different localities and with reference to other questions.
There does not seem to be any extensive migration along the
coast, and it would appear that the animals are confined more
or less to the bays or localities which they inhabit. A series
of experiments with marked fish would be necessary to throw
light on this point.
Within a restricted area, however, such as Table Bay, there
seems to be a definite movement. Thus at times the animals
are found in abundance at one spot for several days, and then
suddenly hardly a single one will be found, the whole of them
having moved off to some other locality, where they may be
procured as abundantly as before. It has been stated that in
Table Bay they move round the Bay in a circle, returning to
the point from which they started. In the fishing operations
of the Canning Factory it was found that large males were
caught off Mouille Point from February to April or May
(according to the weather). Mostly medium-sized males were
caught off Milnerton and Blaauwberg in May and June.
Medium-sized males and females were caught off Robben Island
between June and October, and during the months of July
and August a good proportion were females. Along the coast
from Camps Bay to Oude Skip catches are made during March
and April, these being nearly all large or medium-sized males.
This, of course, does not point to an actual movement of the
fish from Mouille Point, Milnerton, Blaauwberg and Robben
Island, as the fish caught are apparently not the same kind,
differing as they do in size and in sex.
[C.P. 5—13.]
40
The method of progression of the animal would seem to
indicate that it can migrate to no great distance, as it can
only crawl rather slowly by means of its walking legs or make
rapid but spasmodic darts by the flexure of its large tail.
That we cannot draw such conclusions, however, is rendered
probable from the experiments with marked crabs and lobsters
in Europe and America, and the interesting occurrence of craw-
fish apparently on a grand trek has been observed. This
was at Stompneus Bay on the Malmesbury coast, and is re-
corded by Mr. MacLachlan who, on one occasion, observed
the usual indications of the passage of a shoal of fish close
inshore moving in the direction of Lambert’s Bay. Steps were
taken to put out the seine net for their capture, and this was
successfully effected. Instead of fish, however, it was found
that the take consisted of crawfish.
Definite movement from one place to another within a
limited area therefore does certainly occur and possibly move-
ments on a larger scale. The former is probably determined
by a variety of causes. It is stated, for instance, that the large
male crawfish found from February to April off Mouille Point
will remain there sheltered from the prevailing south-east
winds till the first strong north-west wind, when they all
disappear from the locality and find shelter under the lee of
Robben Island. Again, there must be definite movements in
connection with the breeding season, when males and females
come together, as, at other seasons, the males and females
congregate by themselves in entirely different localities, as
is seen in the account of the experimental hauls. Thirdly,
there is a definite movement on the approach and after the
period of the casting of the shell. This movement is said to
be in some cases towards rocky ground, where shelter from
enemies may be found in the nooks and crevices of the rocks ; in
others towards a sandy shore, where the animals bury them-
selves up to the eyes in sand and there they remain
until new hard shell is acquired.
12. LIFE HISTORY OF THE CRAWFISH.
The egg, still attached to the ventral side of the tail of the
mother, is hatched in the spring of the year in shallow water.
From the egg emerges the first larval form already des-
cribed, and this rapidly ascends to the surface of the water-
remaining there probably without taking food.
It then, within a few hours, changes into another form
(the Phyllosoma) provided with other and entirely different
organs of locomotion, adapted for swimming chiefly in a
41
horizontal direction, and for the capture of minute floating
particles of food, abundant during the summer months.
Later, free swimming stages succeed these, but whether
they are numerous and last for weeks or months is not yet
known. These free swimming forms are glassy and trans-
parent and swim about rather slowly and without the timidity
which characterises later stages. Probably their transparency
helps them to avoid their enemies.
Ultimately, however, these free swimming forms settle down to
the bottom, lose their swimming appendages, and seek refuge
in seaweed and rocks in the shallow parts of the sea, avoiding
as best they can the numerous enemies of this stage. It is no
longer transparent and invisible to its enemies, and is timid
and wary in its movements. The body becomes opaque and
pigmented. The inner branches of the walking legs come into
use for the first time as organs of locomotion, and it can
crawl into crevices; the outer swimming branches are lost.
The tail region increases very considerably in size and forms
a powerful organ of locomotion, as, by its sudden flexure, it
is capable of projecting the body backwards at a rapid rate,
away from any suspected source of danger.
As it increases in size with succeeding moults the animal be-
comes better able to defend itself, and it may venture further
afield.
The remaining stages of its life history differ according to
whether it is a male or female.
During or towards the end of the winter months the female
casts her shell and soon after has connection with the male,
and lays the eggs which become attached to the underside
of the tail.
The eggs are carried about in this way for some months
and the female finds her way into shallow water, the male
into deep water.
In the early summer months the eggs of the female, which
is then in shallow water among seaweed, hatch out.
Meanwhile the males in the deeper water begin to cast
their shells and gradually to build up a new one. They are
then in poor condition, being described by the fishermen as
“sick,” and are unfit for food. This lasts till about the end
of January or the beginning of February, when the fish have
fully acquired the new shell, and the body fills up so that they
are described as in ‘“‘ good condition”? by the fishermen.
During this sick condition they apparently do not eat much
and are scarcely to be tempted by bait, finding shelter in
crevices of the rocks or burying themselves in sand.
[(C.P. 5—’13.]
42
13. PRESERVATION OF THE CRAWFISH.
We have seen that the close season, which has been adopted
with a view to the protection of the Cape Crawfish, corres-
ponds to the months in which the males are in deep water
engaged in casting their shell and in a sickly condition, They
do not take the bait readily at this time and are unfit for
commercial purposes. The females are at this time in shallow
water, some still carrying their eggs, but most having got
rid of them.
This is therefore the most favourable season for the fishermen
and the factories to suspend their operations, but it is doubtful
if the ‘“‘ protection ” thus afforded by such a close season is
of any considerable value. The males cannot readily be got.
and are unfit for canning, so that fishing operations for the
factories would be confined to females, but the females which
have spawned in this season are just those which presumably
could best be spared and the catching of which would do the
least harm. As the females which have just given rise to pro-
geny are of less value economically than those about to do
so, the most effective close season would cover the months
just previous to the time at which they get rid of their eggs.
However suitable this close season may be therefore for the
fishermen it cannot be held to be the most effective for pre-
venting overfishing and damage to the supply.
A second means adopted for the preservation of the industry
was to impose a size limit of 3 inches (measured from the base
of the eyestalk to the end of the carapace or shield). It was
enacted that no crawfish below this size should be caught.
This however protected, it is to be noted, three different classes
of crawfish: first, the very small forms (males and females)
such as were of commercial use as a delicacy ; second, the
adolescent and sexually mature males; and_ thirdly, the
adolescent and secondly mature females. We have adduced
reasons for believing that the first are particularly hable to
the attacks of such natural enemies as the octopus, and nature
has made special provision for a natural drain on these forms
by their large numbers so that the damage caused by man is
probably insignificant as compared with the normal mortality
at this season. With regard to the second, the protection of
young adolescent males, these it would appear are just the
forms which can most readily be dispensed with, being the
least valuable from the point of view of the preservation of
the species. An analogous case is that of seals, where the
young males or “bachelors” are found to be those that
can be killed off with least damage to the industry. In both
a0)
cases the animal is polygamous, and there will probably always
be a sufficient number of males to fertilise all the females.
With regard to the third it would seem that the young female,
reproducing, or about to reproduce its kind, should be the object
of special care. Without doubt this protection does considerably
safeguard the continuation and multiplication of the species,
but it might be suggested that later stages, in which the
female may be more fertile and capable of reproduction,
should be the object of still more special care. A female at
the zenith of its reproductive powers is the most valuable
from the point of view of the preservation of the species. It
would appear that as a matter of fact (though it is a point
still to be investigated more fully) this period in the life of
the female is between 2} and 4 inches, so that the strict
preservation of these forms would be the best means of
safeguarding the industry. It could not, however, perhaps
be found practicable to enforce such a regulation. The fish
are caught in nets and promptly tumbled into the boat, often
in the dark of early morning, when there is neither time nor
opportunity for readily separating out and throwing back
into the sea females between 2} and 4 inches long. The
difference between male and female are, however, as has been
pointed out, well marked, and are seen by the experienced
fishermen at a glance, and if any relaxation of the restrictive
measures be contemplated in the future, in view of stricter
protection of the females it might quite well be in allowing
the capture of young males.
A third direction in which the protection of the crawfish
has been sought is the protection of ‘‘ berried ’’ females or
females carrying eggs externally. This is one of the most
obvious methods of dealing with the problem, and regulations
to this effect cannot but be very useful, though they have been
avoided, it is said, by stripping the female of eggs before
landing the catch. Females with the ovaries well-developed
and with internal eggs demand protection, however, quite as
much as those with external eggs, and the only fault with the
regulation is that it implies the non-protection of such females.
A fourth method of ensuring the continuation of the supply
of crawfish is one which has not yet been tried, but has been
adopted for some time in the case of the lobster of the Northern
Hemisphere. It is that of artificial hatching, which may be
carried out by collecting the eggs and by a system of artificial
aeration keeping them until the young hatch out. These young,
free-swimming forms are then turned into the sea, having
probably been tided over a dangerous period of their develop-
ment. This method could probably be easily carried out in
the case of the South African Crawfish.
[G.P. 523; ] E
44
Lastly, artificial hatching can be rendered still more effective
by artificial rearing, namely by keeping the free-swimming forms
in comparative security from the attacks of their natural enemies
by rearing them in ponds or enclosures until they have passed
the pelagic stage and have become ground-frequenting forms.
It is possible, however, that this may not be easily accom-
plished in the case of ‘the crawfish, as it apparently passes
through a long free-swimming larval stage. Further investi-
gation of this point is required.
With regard to the general question as to what steps should
now be taken to modify or extend the present laws, with a
view to preserving an industry which is apparently threatened
by inadequate protection and by the prospect of much more
extensive fishing operations in the immediate future, it would
appear that the most effective means would be the protection
of the female between 2} and 4} inches (new measurement).
There does not appear to be the same need for protecting the
very young forms, up to say 14 inches, nor the males of any
size, but in view of the threatened decrease in the supply it
may not be advisable to withdraw any of the present restric-
tions, (including four months close season as recommended by
the Fisheries Advisory Board), which do not impose a very
heavy burden on fishing operations and afford some _ pro-
tection however small and inadequate. The proposed alteration
therefore would be the ratsing of the size limit from 3 to 4 inches,
measured from the base of the eyestalk to the end of the carapace
(or four and one-fourth inches measured from the tip of the
rostrum or beak).
Still more effective measures would be the protection
throughout the year of all female crawfish, and this may yet
have to be seriously considered.
It is to be borne in mind in framing such regulations that
the ordinary fishing operations of the Cape fishermen for the
Cape market do not seem to have affected the supply so
seriously as those of the canning companies for oversea mar-
kets, if indeed the former have affected it at all, and the question
may therefore be raised as to whether a distinction should
not be made betw een these two in framing restric tive regu-
lations.
Whatever difficulty there may be in adjusting the difference
between the immediate interests of the factories and the
permanent preservation of the industry, there is no such
trouble in the methods of preserving or augmenting the
supply of crawfish by means of artificial hatching and rearing,
and all agree as to the desirability of carrying on further
investigation which may lead to a more adequate knowledge
of the life history of the crawfish and possible practical results
of great economic importance. Steps should at an early date
be taken in the matter of arttficial hatching. In the emphatic
words of the manager of the Hout Bay Factory “ the sooner
such a course is adopted the better; it is inadvisable to follow
the example set in the Northern Hemisphere and wait until the
fishing grounds are denuded before making the experiment.”
Finally, the question of controling crawfish factories and the
procuring of reliable returns of quantities and conditions of fish
caught should receive careful consideration, and adequate
means should be taken for inspection.
Note.—In carrying out these investigations on the Crawhsh
and Crawfish Industry [have been greatly assisted by the ready
co-operation of the Managers of the Crawfish Factories, to
whom I desire to express my obligations. The actual fishing
operations mentioned on p. 5 were efficiently carried out by
the Fishery Officer, Mr. Cripps.
[C.P. 5—’13.]
il. REVIEW OF THF SOUTH AFRICAN CLUPEID/
(HERRINGS) AND ALLIED FAMILIES OF FISHES.
Owing to a lack of definite descriptions and figures of South
African fishes there has been considerable doubt as to what
fish really occur in South African waters. This is well illus-
treated in the case of the Herring family, which contains so
many fish of economic importance. Thus, in the early records
of Van Riebeek, mention is made of Herring. In his Journal,
under the date February 24th, 1654, he wrote :—‘‘ Caught
on board the Calff half a boatful of fine herrings—about 1,000
were salted—making the finest pickled herring in_the World.
Never caught so many together; generally only found three
“or four in a shoal of harders, which, when salted, were found
to be very delicate, and will be a great treat for the officers
of the return fleet.” From time to time since this date dis-
coveries of the existence of Herring in South African waters
are recorded. Only a few years ago much was made in the
local press of the Eastern Province of such a discovery, and
hopes entertained of the possible development of a herring
industry on lines rivalling that of the North Sea. The ‘‘ Penny
Mail”? gave an emphatic assurance that these were “ true
Herring.” Nothing further, however, in the way of more
definite information or practical results followed.
In the year 1853 a fish called the Shad or Sardyn was
described by Pappe as a new species of Clupea, and was given
the name Clupea ocellata. The description is mainly of the
colour of the fish, other characters of specific value unfor-
tunately not being mentioned. It is as follows :—** Body
compressed, elongated; head flattened at top; muzzle
obtuse ; upper jaw with a central notch and a little projecting.
No teeth in either mandible ; eyes and scales large. One
dorsal only, tail deeply forked. Length, 6 to 7 inches. Head
and back blue, changeable to green and shaded with purple,
yellow and gold. Lower jaw and gill cover silvery, with a
reflecting golden lustre; sides above the lateral line crossed
by a sky blue longitudinal stripe. A line of eight to fifteen
round, blacls, eye Aight (eyelike ?) spots extends from the edge of
the operculum along the whole body. Belly silvery. Iris
eilt.”
47
In 1860 Bleeker, in his ‘“ Vische v. d. Kaap,”’ mentions:
C. ocellata as a Cape fish but without further description, and
in 1861 Castelnau (“‘ Mémoire sur les Poissons de |’Afrique
australe’) gives a short description, again of colour only.
He draws attention to its resemblance to the common Herring,
without however adding any further details of importance.
He says :—‘* Cette espece ressemble au Hareng commun
mais s’en distingue par une série de points noires, espacés,.
assez grands et ocellés, qui suit le ligne latérale. Ils varient
en nombre, de 5 a 12 de chaque coté du corps. Le dos et
le dessus de la tete sont d’un beau bleu éclatant. Le reste
dun blanc argenté, un peu doré; nageoire dorsale jaune en
avant.—Caudale cendrée, les autres nageoires blanches ; |’ iris
jaune. Se peche en eté, mais assez rarement.”
There is little doubt that Van Riebeek’s “ fine herring,”
the “Penny Mail’s” “true herring,” “‘Clupea ocellata,
Sardyn or Shad” of Pappe, and Castelnau’s fish resembling
a *“*‘ Hareng commun” are one and the same fish. A number
of specimens of a fish corresponding to these descriptions
have been recently captured alive and put into the tanks
at the Marine Station, St. James, thus affording good material
for a more definite determination as well as observations of
the animal in the living state.
A second member of the family, not generally known to
occur in South Africa, though abundant at times, is a species
of Anchovy, almost identical with the European Anchovy.
It is not distinguished from the Herring by Cape fishermen,
who include both under the name “Sardine” It is first
definitely mentioned by Pappe, who took it to be identical
with the European Anchovy, Engraulis encrastcholus, L., and
gave the common name as “ Ansjovis or Anchovy” His
description is as follows :—‘‘ Body slender ; head and snout
pointed ; upper jaw projecting considerably. Mouth deeply
and horizontally cleft far behind the eyes. Maxillaries and
palate armed with small but sharp numerous teeth. Scales
large and deciduous ; tail deeply forked. Top of head and
back blue, with a tinge of green; flanks and belly silvery.
Fins greenish-white. Length, 4 to 5 inches.”
Bleeker (l.c.p. 56) mentions Engraulis encrastcholus as a
Cape fish, evidently quoting from Pappe, and Castelnau
(l.c.p. 68) had some doubt as to the identity of the fish with
the European form as identified by Pappe. “Ce n’est qu’
avec beaucoup de doute que je rapporte ce petit poisson du
Cap a l’espece européenne, mais je n’al pas cette dernicre a
ma disposition et depuis, par conséquent, les comparer ; je
me range done a l’avis du docteur Pappe, en les réunissant
(CP. 5135]
)
48
en une seule espéce.” In spite of the apparent resemblance
to the European Anchovy, this South African form, as will be
shown later on, appears to be a different species, which I have
named Engraulis capensis.
In 1900, young specimens of an Anchovy were found in
some experimental netting in the Zwartkops River, and were
described as a new species, Engraulis holodon, by Boulenger
(Mar. Inv. in South Africa, Vol. I., p. 12). Those he took to
be probably the fish referred to by Pappe and Castelnau, and
pointed out that they were not the European species as these
authors had supposed. He says: “ The ‘ Ansjovis’ of the
Cape fishermen has hitherto been referred to E. encrasicholus,
without having been compared with European specimens.
These, as well as the Australian and Neo-zelandian EF. antipodum
differ in the narrower and shorter maxillary, the toothless
mandible, and the dorsal fin entirely in advance of the anal.”
In 1906 a new species of Herring (Clupea durbanensts) was
‘described by Regan from the Coast of Natal (Ann. Nat. Gov.
Museum; Volo. pant 1 p04).
In 1908 two new species were added to the South African
‘Clupeide by Gilchrist and Thompson, viz. :—Engraulis
vitrivostus and Pellona (Llisha) natalensis (Ann. S. Afr. Museum,
Vol. VI., part 3, p. 201) from the Coast of Natal.
In 1909 the same authors recorded and described another
seven members of the family, also from the East Coast, viz :
Engraults setirostis, Brouss, Etrumeus muicropus, Schleg , Clupea
sagax, Jenyns, Albula conorhynchus, Bl. et Schn., (A. vulpes L),
Elopss saurus L., Megalops cyprinotdes, Brouss, and Chanos
salmoneus, Forst.
The family Cluperd@ has been defined as fish with the
margin of the upper jaw formed by the premaxillaries and the
maxillaries. Body scaly; head, naked; abdomen, usually
keeled ; short dorsal fin ; no adipose fin ; respiratory mechanism
well developed, the gill openings being usually wide, opercular
pieces complete and pseudobranchie usually well developed.
This definition includes a variety of groups which later authors
have found it desirable to divide up into a number of distinct
families. It includes the following South African forms: (1)
Elops saurus, (2) Megalops cyprinoides, (3) Albula conorhynchus,
(4) Chanos salmoneus, (5) Etrumeus micropus, (6) Spratteloides
cestuartus, (7) Clupea durbanensis, (8) Clupea sagax, (9)
Engraulis holodon, (10) Engraulis capensis, representing
the families of the Elopide (1) and (2), Albulide (3),
Chamde (4), Clupetde (5-8), Engraulide (9) and (10), as
in the following table :—
49
CLASS PISCES.
SUB-CLASS TELEOSTOMI.
ORDER TELEOSTEI.
SUB-ORDER MALACOPTERYGII.
Famity 1: ELOPIDA.
1. ELOPS, JL.
I. saurus, L.
2. MEGALOPS, Lacey.
]. cyprinoides, //0uss.
: ALBULID.
1. ALBULA, Grono.
1. vulpes, ZL.
FAMILY
Nd
=)
Famity 3: CHANIDA.
1. CHANOS, Lacep.
1. salmoneus, /vvsf.
Famity 4: CLUPEIDA.
1. ETRUMEUS, 5//v.
I]. micropus, Schleg.
2. SPRATELLOIDES, B//r.
1. estuarius, Gi/ch.
3. CLUPEA, Civ.
1. sagax, Jenyns.
2. durbanensis, Rega.
4. ILISHA, Gray.
1. natalensis, Gilch d) Thomp.
Famity 5: ENGRAULIDA.
1, ENGRAULIS, C. d V.
1. holodon, Blg7.
2. capensis, Gulch.
3. vitrirostris, Gilch & Thomp.
4. setirostris, Dyvouss.
50
Key to Families.
1 Bony plate between branches of
lower jaw .. eE ELOPIDZ
2 No bony plate between branches of
lower jaw
1 Lateral line well developed
I Teeth present, no accessory
branchial organ... oy .. ALBULIDZ.
2. Teeth absent, an accessory
branchial organ... as .. CHANIDZ.
2. Lateral line absent.
1. Mouth terminal vi le .. CLUPEID A.
2. Mouthinferior, longsnout .. .. ENGRAULIDZE.
Famity 1. ELOPIDA.
Margin of upper jaw formed of premaxillaries and maxil-
laries, which extend backwards beyond the eye, a bony plate
between branches of lower jaw. Pharyngeal teeth . Branchio-
stegals numerous. Gill rakers rather long and slender. Body
not keeled. Lateral line present. Parietal bones meet above
head. Widely distributed in tropical and sub-tropical seas.
Key to Genera.
A. Scales, small; dorsal a little longer
than anal. ot BS . eee OpS alee
B. Scales, large ; dorsal a little shorter
than anal, with last ray much produced .. Magalops, Lacep.
I. ELOPS, Linnaeus.
Linn. syst. Nat. Ed. XII, p. 518 (1766).
Mugilomorus, Lacep. Hist. Nat. Poiss. V, 398 (1803).
Body elongate with thin small scales. Lateral line straight,
with simple tubes. Mouth very large, small teeth in pre-
maxillaries and maxillaries, lower jaw, palatines, pterygoids,
parasphenoid and tongue. Dorsal fin slightly behind v éntrals,
both depressible within a sheath. Pseudobranchice w ell
developed. The young are ribbon-shaped, like young eels.
1. Elops saurus, Linn.
Linneus, Syst. Nat. Ed. XII, p. 518 (1766); Bloch, Aust.
Fische, VII, p. 153, pl. CCCXCIM, te. 14(t7o4), ea
and Val. Hist. Poiss. XIX, p. 365 (1846); Gunth. Cat.
Fish, VII, p. 470 (1868) ; Steind Sitzb. b.ak. Wien, LXI,
an
H
i. p 571 (1870). Kleinz. Verh. Zool_—bot. Ges. Wien,
XXI., p. 603 (1871); Bleek. Atl. Ich. VI., p. 84, pl.
COLVIN dic. 3 (1872). Day, Fishes: Ind. p: 649," pl-
CXLVI, fe. (1878), Se:
Depth of body 4} to 5} times in total, length of head 3} to 4
times. Eye 4 to 5 times, about equal to snout and interor-
bital width. Lower jaw scarcely projecting beyond upper.
Scales about 100—1x20 in a longitudinal series, }4— }{ in
in a transverse series, g—1I0 between lateral line and scaly
process above ventral, 28 round caudal pednule.
Dorsal 22—25, Anal 13—17.
Branchiategals 28—35.
Colour silvery.
This fish is abundantly distributed in tropical and sub-
tropical seas, and may grow to a length of 3 feet.
Elops saurus, The “Springer” or “ Salmon” of the East Coast (Blgr. after Day).
At certain seasons it ascends rivers and is known to fishermen
on the East Coast as Cape Salmon, a name usually applied
elsewhere in South Africa to the Geelbek (Ofolithus equidens).
It affords excellent sport to anglers, and, in this respect,
resembles its namesake the salmon more than _ the
geel-bek. Though known by this name at Port Elizabeth
and East London it is called the “‘ Springer ” in Natal, a name
applied to a mullet, or “harder,” in other parts of South
Africa. The largest specimen recorded (Mr. Robinson, Natal)
was 15 lb. in weight: He writes “ The springer is related to
the tarpon, which it resembles in the fire and speed of its
movements when hooked: and its frequent leaps out of the
water when seeking to rid itself of the hook. It is a beautiful
silvery fish with large scales, but, owing to its violent struggles
when landed, it generally damages its skin, arid it is not easy
to get a perfect specimen. .... Its flesh is too pappy and full
of bones to be edible. It will take most baits, but it is difficult
to land owing to its soft mouth.” Plate II. is from a photo-
graph of two specimen caught at Delagoa Bay.
The young of the fish are ribbon shaped.
[C.P. 5—'13.]
52
2. MEGALOPS, Liacep.
Lacep.. Hist: Poiss. Vs p. 289°(1803); Gunth Cats Fish Vit
p- 471 (1868) ;. Bleek. Atl. Ichth. VI, p.85 (1872).
Tarpon, Jordan and Everm. Fish. N. Amer. I, p. 409 (1876).
Body not so elongated as in Flops and strongly compressed.
Scales large ; lateral line with branched tubes. Mouth large,
small teeth in premawxillaries, maxillaries, vomer, palatine,
pterygoid and tongue. Dorsal fin above or slightly behind
ventrals, its last ray produced no pseudobranchie.
1. Megalops cyprinoides, Brouss.
Clupea cyprinotdes, Brousson, Ichthyol, pl. 1x (1782).
Megalops filamentosus, Lacep. Hist. Poiss. v. p. 290, pl. xiii,
fig. 3 (1803); Bleek. Nederl. Tijdschr. Dierk. ii, 1866,
p. 286, and Atl. Ichth:, VI. p. 86, pl. cclxxim, fig. 1(1672):
Cyprinodon cundinga, Ham. Buchan. Fish. Ganges, p. 254
(1822).
Megalops setipinnis, Richards. Ann. N. H. xi, 1843, p. 493.
Acs Ne oy ( LOM:
oye Nene ne Mold
BeNOR a
py ee
Megalops cvprinoides, A“ Tarpon” of the East Coast (Blgr. alter Day).
Megalops curtifilis, Richards. Ichth. China, p. 310, (1846).
Megalops indicus, Cuv. and Val. Hist. Poiss. xix, p. 388, pl.
eecccexIm (846); Bleek: Verh: Bat\Gen® xadv; 1052500
7a Ohne oe
Elops cundinga, Cantor, Cat. Mal. Fish., p. 289 (1850).
Megalops macrophthalmus, Bleek. Verh. Bat. Gen. xxiv. 1852,
1iNese feg | Okay 1ESy
Megalops macropterus, Bleek. Nederl. Tijdschr. Dierk. 111, 1866,
p. 284,.and At tic:p: 85) pl iccla xin, shes 2
Megalops kundinga, Bleek. tt. cc. pp. 288, 87, pl. cclxxiv, fig. 1
Megalops cyprinoides, Bleek. t.c.p. 290; Gtmnth. Cat. Fish.
Vil,/p. 471 (1868)%: Bleek. Ath-tic.p. 87, pl: echac iis
Day, Fish. Ind. p. 650,-pl. clix, fig. 3 (1878); Sauv.
Hist. Madag. Poiss.p. 407, pl. xlix, Ay fis. 3 (60m);
Pfeffer, Thierw. O.-Afr., Fische, p. 70 (1896).
on
Oo
Megalops oligolepis, Bleek. t.c.p. 292.
Elops apalike, Day, Fish. Malab., p. 228 (1865).
Elops cyprinoides, Playf. & Gunth. Fish. Zanzib. p. 122 (1866) ;
Peters, Reise Mossamb. iv, p. 92 (1868).
Depth of body equal to or a little greater than length of
head, 3 to 4 times in total length. Eye 22 to 3} times in length
of head, greater than length of snout or interorbital width ;
lower jaw projecting beyond upper; maxillary extending to
below posterior border of eye or a little beyond. Gill-rakers
at least as long as gill-filaments, 25-35 on lower part of an-
terior arch. Dorsal 17-20, originating above base of ventral.
Anal 24-28. Scales 37-42, ?—{%, 4-5 between lateral line and
scaly process above ventral, 12-14 round caudal peduncle.
Silvery, bluish green on the back.
Famiry 2. ALBULIDA.
Margin of upper jaw formed ot maxillaries. Small teeth
in jaws, vomer and palatine; patches of coarse flat teeth
on tongue, sphenoid and pterygoid. Branchiostegels about
Albula vulpes.
14. Gillrakers, short. Body not keeled. No bony platse
between jaws. Parietal bones meet above top of head. Young
pass through a ribbon-like larval stage.
ALBULA, Gronov.
Gronov. Zoophyl, p. 102 (1763); Block & Schneider Syst.
Ichth.; p. 432 (780x)
Buitrynus, Lacep. Hist. Nat. Poiss., v. p. 45 (1803).
‘Glossodus (Cuv.) Agassiz in Spix. Pisc. Brasil, p. 48 (1829).
Albula vulpes, L.
Jordan and Everman, Fishes of North America, p. 411.
(see synonymy)
Albula conorhynchus, Gilch. & Thomps. Ann. S. Af.
Museum. VI., p. 269 (Natal).
Depth of body nearly 4 times in total length, excluding
caudal, length of head 3°. Snout, 24 times diameter of eye,
which is nearly 1} times in interorbital width and 6 times in
[C.P. 5—13.|
54
length of head. Maxillary reaches to vertical of about + the
distance between point of snout and anterior margin of eye.
Profile from origin of dorsal to point of snout convex.
Dorsal 17, commences a little nearer to base of caudal
than to point of snout, and ? of its base is situated in advance
of the ventrals; anterior rays nearly ®* length of head, pos-
terior margin of fin slightly concave. Pectorals ? length of
head. Ventrals over 4 length of head, inserted below last
4 of dorsal. Anal, 8; about 4 length of dorsal and } height.
Caudal forked, upper lobe longest and about ,’, length of
head; Lat. 1. 70, nearly straight; lat. tr...
Colour (of preserved specimen), silvery, darker above.
(This description is of the Natal specimen).
Famiry 3. CHANIDA.
Premaxillaries joined to anterior edge of maxillaries. No
teeth. Branchiostegels, 4; pseudobranchie well developed.
An accessory branchial organ. Lateral line well developed.
Eye with adipose eyelid. Abdomen broad, flat.
CHANOS, Lacep.
Lacepede. Hist. Nat. Poiss. v. 395 (1803).
Lutodetra (Kuhl) Ruppel, Neue Wirbelthiere Abyssinia, 18,
(1835).
Chanos salimonens (Alter Day).
Ptycholepis, Gray, Dieffenbach’s Travels in New Zealand,
II, 218 (1842?).
The only genus in this family.
Chanos salmoneus, | orst.
Day, Fishes of India, p. 651 (see synonymy) Gilchrist &
Thompson, Ann. S. Afr. Mus. VI. p. 271 (Natal).
Depth of body, 3} times in total length excluding caudal ;
length of head, 4? times. Snout, } diameter of eye, which is.
I} times in interorbital width and 3,%, times in length of head.
Eyes, subcutaneous ; upper surface of head flat ; upper jaw
overhangs lower, maxillary reaches almost to vertical of
anterior margin of eye ; opercle’nearly twice as high as broad.
a)
Dorsal 15 commences about midway between anterior
margin of eye and base of caudal, highest in front, upper
margin concave, 2 rows of scales at its base ; longest rays
nearly ¢ length of head. Pectorals pointed, % length of head,
with an elongated scaly appendage above the base. Ventrals
5 length of head, inserted under middle of dorsal and with a
long basal scale. Anal 9, small, lower margin concave, 2 rows
of scales at base ; anterior rays about 7 height of longest ray of
dorsal. Caudal deeply lobed, 14 times length of head, with two
pointed laminz of scales at its centre. Lat r. 87, lat. tr. 12.
Colour (of preserved specimen) bluish on top, silvery below ;
dorsal dark, and both it and anal and ventrals covered with
minute dark specks, pectorals dark and also with minute
specks. (This description is that of the Natal specimen).
FAMILY 4. CLUPEIDA.
Mouth, large terminal ; maxillaries forming margin of upper
jaw, each of three pieces. Teeth, small, rudimentary, or
wanting. Branchiostegels 6-15. Pseudobranchize present. No
lateral line. Eyes with or without adipose eye-lids. Abdomen
rounded or compressed and frequently armed with bony plates
(includes the group Clupeina and Dussumieriina of Gunth.,
V1, 413-467). |
Key to Genera..
Belly rounded, no abdominal scutes, a silvery band.
Dorsal, 11-18 Ses ae .. wee SPRATTELOIDES.
Belly rounded, no abdominal scutes, no silvery band.
Dorsal, 18-20 ie uae a ETRUMEUS.
Body compressed with scutes.
Anal, 15-25... Pr Le Ms CLUPEA.
Body compressed, with scutes.
Anal of more than 30 rays x ILISHA.
SPRATELLOIDES, Bleeker.
Body elongate, slightly compressed, without abdominal
scutes. Mouth terminal. Scales deciduous. Teeth minute
or absent. Dorsal opposite or nearly opposite ventrals.
Spratelloides zstuarius, n. sp.
Depth of body, 4! in total length, excluding caudal; equals
length of head. Snout 3% times in length of head, shorter
than diameter of eye, which is four times in head; the lower
jaw slightly projects beyond upper. Maxillary, broad ; reaches
to near vertical of anterior border of eye. Supplemental
bone broad ; slightly broader than maxillary. About 30 gill-
rakers on the lower branch of the outer gill-arch.
fe. Po 5/135]
50
Dorsal 15, much nearer root of caudal than end of snout,
these distances being in the proportion of 5 to 8. Anal 20,
begins under the end of the dorsal. Ventrals inserted slightly
in front of dorsal.
About 40 scales in a longitudinal and to in a transverse
series. A patch of small teeth on the anterior end of pre-
maxillary and mandible. The maxillary denticulate. There
are no scutes on the abdominal margin between pectorals and
ventrals nor behind ventrals, but there are three or four fused
into a rather sharp and hard ridge on the thoracic region in
front of pectorals.
This fish is common in the tidal portion of the Zwartkops
River near Port Elizabeth, where it is known as ** White-bait.”’
It is found also in some of the tidal rivers near East London.
Spratelloides astuarius, n. sp.
A fish apparently identical with it has been found by Mr.
W. W. Thompson in Princess Vlei, a sheet of practically fresh
water on the Cape Flats.
ETRUMEUS, Bleeker.
Bleeker, Verh. Bat. Gen. xxv., 48 (1853).
Body, elongate, shightly compressed ; abdomen, rounded,
without scutes ; mouth, terminal ; scales, cycloid, very decidu-
ous ; ventrals, entirely behind dorsals.
Dorsal fin long and low. No silvery lateral stripe. !
Etrumets micropus.
Clupea micropus, Schleg. Faun. Japon. Poiss, p. 236, pl. 107,
fig. 2.
“Benen micropus, Bleeker,. Verh. Bat. Gen. xxv, p. 48.
Gilch. and Thomp. Ann. S. Afr. Mus. vi., p. 268 (1909).
Depth of body 6 times in poral length excluding caudal,
length of head 4} times. Snout 2 diameter of eye, which is
nearly 2;, times in length of head and twice the interorbital
width. Lower jaw slightly projecting beyond upper, maxillary
reaches to vertical of anterior margin of eye.
if
On
Dorsal 18 ; originates nearer to point of snout than to base
of caudal by about the length of the base of dorsal fin; 2nd
and 3rd rays 3 length of head, remainder rapidly shortening,
upper portion of fin slightly concave. Pectorals ,*, length of
head, axillary scale very long. Ventrals about 4 length of
head. Anal 10, originates in posterior sixth of body, low.
Caudal nearly ,°, length of head, forked. Scales 52-54. Lat.
mae ges
Colour (of preserved specimen), dark on back above lateral
line, sides and belly silvery.
This fish is recorded also from Japan. The above description
is of a specimen from Natal.
CLUPEA (Artedi) Linn.
(Artedi) Linnaeus Syst. Nat. Ed. x, 317 (1853).
Rogeina, Cuvier & Valenciennes, Hist. Nat. Poiss., xx, 340
(1847). .
Alosa, Cuv. Regne Anim. 2nd Ed. ii, p. 319 (1820).
Body compressed, with abdominal scutes, no lateral line.
Maxillary of three pieces. Teeth present or absent. Dorsal
fin short. Anal elongate. Ventrals with 6-9 rays.
Key to Species.
Depth of body about 5 times in total length : C. sagax.
Depth of body about 2} times in total length : C. durbanensis.
Clupea sagax, Jenyns.
Jenyns, Voyage of the Beagle, Fishes, p. 134, 1842 (Lima).
Gilchrist & Thompson, Ann. S. Afr. Mus., Vol. vi, p. 269
(Natal).
Alosa fimbriata, Kner & Steindachner Sitzl, Akad. K. Wien
1886 (Chili).
Clupea ocellata, Pappe, Synopsis of the Edible Fishes of the
Cape of Good Hope, p. 20, 1853; Bleeker, over eenige visch-
sorten van de Kaap de Goede Hoop. Nat. T. Ned. Ind. XXI,
1860, p. 56 ; Castelnau, Mémoire sur les Poissons de I’ Afrique
australe, p. 67, 1861.
Body elongate, compressed, depth slightly over 5 times in
total length excluding caudal, length of head 3? times, greatest
breadth of head about half its length. Snout 1! times the
diameter of the eye, which is equal to the breadth of the
interorbital space.
(CBs 13.
58
Adipose eyelids present, each covering about 4 of the diameter
of the eye. Lower jaw scarcely projecting beyond upper,
equal when completely closed. Maxillary extends to anterior
third of eye. Lower branch of the outer branchial arch long,
nearly straight, with about 115 gill-rakers, the longest of which
is slightly longer than the diameter of the eye and slightly
less than the length of snout.
Scales of the upper part of the body in front of dorsal striated
and ciliated, those of the sides and belly smooth and slightly
ciliated. They are regularly arranged and loose. Abdominal
scutes in front (19) ma behind (12) ventrals. Two of the
anterior are in front of pectorals. About 54 scales in a longi-
tudinal and 12 in a transverse row. Teeth absent in jaws
and palate and tongue, which however has a sharp, rough,
bony ridge.
Dorsal III 16, a little in front of middle of body, me distance
between tip of snout and beginning of dorsal being 2! in total
length. The longest ray a little more than the length of the
Clupea sagax, The Cape Herring or Sardine.
head and equal to the length of its base. Anal III] 15. Be-
ginning of ventral below posterior part of base of dorsal, its
longest ray 13 in head. The length of pectoral is 4 its distance
from the ventral.
The colour of the fish when alive and observed swimming
in the water appears of a silvery, slightly greenish shade. This
uniform colour is only broken by the black spots along the side.
These may be numerous, few or entirely absent. When re-
moved from the water, and especially when the easily-detached
scales fall off, the variety of colours recorded by Pappe and
Castelman may be observed. The lower 4 of the body is then
of a bright silvery colour sharply m: irked off by a straight line
from the upper third, which is of a vivid green or greenish blue
tint. The-line of demarcation follows the line of greatest
diameter of the body, so that when viewed from above, the
fish is of a dark blue or green colour, and when viewed from
below of a bright silvery hue ; the sharp line of demarcation is
39
interrupted by the series of dark spots which has suggested
the specific name of the fish. These range from about 20,
extending from the head to the tail, to a few at the anterior
end of the body and in some cases are absent. The position of
each scale is marked on the upper part of the body by a small
black dot and, in some cases, there are two or three larger black
marks, symmetrically placed on each side at the base of the
dorsal fin.
The ovaries were examined and were found to be not fully
developed. In a specimen 40 mm. in length from snout to tip
of caudal and weighing 84 grammes, the ovaries weighed 3
grammes. The largest ovum was -63 mm. in diameter and
was full of very small oil globules.
Pappe has compared this fish with the Shad of Europe and
gives this apparently as the popular name in South Africa.
This name is not now used, but “‘Sardine.”’ The Shad of Europe
—Clupea finta, the Allis Shad, and C. alosa, the Twaite Shad—
differ from C. ocellata in deeper body, fewer number of gill-
rakers, larger number of scales and other respects.
The fish does not seem to differ from C. sagax Jenyns recorded
(from a single and somewhat imperfect specimen) by Gilchrist
and Thompson from Natal. The type was found at Lima.
Alosa fimbriata, Kner and Steindachner, from Chili, may also
be the same species. It is very closely related to the European
Pilchard (C. pilchardus) small tinned specimens of which are
called ‘‘Sardines.’’ It is sometimes preserved in salt
or oil by the native fishers, and both in this and the fresh con-
dition has an excellent flavour. It would ‘probably make a
valuable article of commerce if cured in sufficient quantities.
The difficulty is to make a beginning and this might be
arranged by offering a reward for the best preserved samples.
Clupea durbanensis, Regan.
Regan, Annals of the Natal Government Museum, Vol. 1,
Part I, p. 4, 1906. Gilchrist and Thompson, Annals of the
South African Museum, Vol. VI, Part 3, p. 269, 1909.
Body comparatively short, deep and much compressed.
Abdominal profile very convex. Depth 2? to 2% in length,
length of head 33 to 33. Snout equals the diameter of eye:
which is 4 to 4} times in length of head, interorbital width
32 to 33.
Eyes with adipose lids, each covering about 4 of the eye.
Lower jaw shut within upper; maxillary extends to below
middle of eye or slightly beyond. Gill-rakers about 200 in
the 2 sections of the lower branch of the outer arch, these two
fC.PS 5— 713. ] F
60
sections forming nearly a straight line. The longest ray equals
the breadth of the interorbital space. Post orbital portion of
head longer than or about equal to remainder of head.
Scales regularly arranged, finely striated ciliated, 43-45 in a
longitudinal, 14 in a transverse series ; 12 scuta behind and 15
before ventral.
Dorsal III 14, a little nearer end of base of caudal than end
of snout, the longest ray equal to the length of its base and
double the length of the last ray. Anal III 17-19. Pectoral
%-2 length of head. Origin of ventral a little in advance of
middle of dorsal. Caudal deeply forked.
Colour: Silvery, a dark spot on shoulder. Edge of dorsal
blackish.
This description is drawn up from that of the authors
referred to, and from a large specimen, forwarded by the
Durban Museum, 240 mm. in length excluding caudal (which
is 76 mm.) the body is deeper, being 2? in total, the Head is
longer (33 in body), eyes smaller 4} in head, the post orbital
position of the head, which, in the other specimen is equal
or about equal to the rest of it, is here decidedly longer, being
1-3 times the rest of the head.
This East Coast Herring 1s a handsome and _ substantial-
looking fish and may occasionally be seen as smoked fish in the
inland cities. It is said, however, to be very bony. It is
recorded as yet only from Natal waters.
ILISHA, Gray.
Platygaster, Swainson, Nat. Hist. il, p. 294 (1839) name pre-
occupied.
Ilisha, Gray in Richards. Ichth. China, p. 306 (1846) ; Bleek.
Ati ichth. val. 16872):
Pellona, Cuv. & Val. Hist. Poiss. xx, p. 300 (1847) ; Gunth.
Cat. Fish, vii. p. 454 (1868).
llisha natalensis (Gilch. & Thomp.).
Pellona natalensis, Gilch. & Thomp. Ann. S. Afr. Mus. Vol.
Viti, ip. 202.
Teeth on jaws, palate, vomer, and tongue. Depth of bodv
2% times in total length excluding caudal, length of head 33
times. Snout nearly $= diameter of eye, which is 1% times
re)
interorbital width and 22 times in le ngth of head. Ridges on
occiput converge very sli ehtly posteriorly and meet anteriorly ;
mouth opens on superior side, lower jaw projects hovers
upper ; maxillary reaches to vertical of posterior nostril ; eyes
large and situated high up, occupying upper half of cael
Dorsal profile almost straight, abdominal profile convex.
O61
Dorsal 17 ; situated about midway between point of snout
and base of caudal. Pectorals 3 length of head. Ventrals
situated just in front of vertical of origin of dorsal and very
small, about + diameter of eye in length. Anal 37 ; commences
below posterior margin of dorsal, length of base 24 times in
total length of body excluding caudal. Caudal forked, as
long as the head. Scales, 16 scutes anterior to and 8 posterior
to ventral fins.
FAMILY 5: ENGRAULIDA.
Mouth very large, upper jaw projecting beyond lower.
Premaxillaries small, firmly joined to maxillaries, which are
formed of three pieces and are long and slender, extending to
beyond eye. Branchiostegels 7-14. _Pseudobranchiz present.
No lateral line. No adipose eyelid. This family is closely
allied to the Clupeide, from which it should perhaps not be
separated.
Engraulis holodon, An East Coast Anchovy.
ENGRAULIS, Cuvier.
Conical snout projecting beyond very large mouth. Maxil-
lary extending beyond eye, but not beyond gill opening.
Teeth small but equal. Dorsals posterior to ventral, about
middle of body. Pseudobranchie present. Branchiostegels
—g-14. Gill-rakers long and slender. Vertebrae about 48.
Key to Spectes.
Anal begins below middle of dorsal — ... x0 > Molodon:
Anal begins behind dorsal sii a8 oo0. Le GAPONSIS.
Anal begins about last ray of dorsal :
Maxillary extends to a little beyond base of
pectoral as on ae Sue ace LeeUDERUNOSTRIS.
Maxillary extends to end of ventral wes Ee Setinesiris:
Engraulis holodon, Blgr.
Boulenger, Marine Investigations in South Africa, Vol. I,
p- I2, 1900.
[C.P. 5—’13.]
62
Depth of body 5 to 54 times in total length, length of head
4times. Snout painreel strongly projecting, shorter than eye,
the diameter of which is three times in the length of the head.
Teeth present in both jaws, minute; maxillary tapering
behind, extending to gill-opening. Gill-rakers long, 12 on the
lower part of anterior arch. Dorsal with 14 rays, originating
a little nearer root of caudal than end of snout. Anal with 19
or 20 rays, Originating below middle of dorsal. Pectoral 3
length of head. Spiny scales of abdomen g in number, extend-
ing between pectorals and ventrals. Caudal deeply forked.
Caudal peduncle twice as long as deep, 40 to 42 scales in a
longitudinal series, 9 in a transverse series. A silvery lateral
‘stripe.
The specimens of which this description is given by Boulenger
were young, the total length being 50 mm. The adults are
not known. They are very abundant in the nettings carried
‘on in the Zwartkops River near Port Elizabeth and are known
as *‘ White-bait,’’ as are also other immature fish, such as
Clupea sagax and Spratlelotdes estuarius. The term ‘‘ white
bait’ is in Europe applied to the young of the peat and
‘other fish,
The Anchovies of warmer seas characterised by a fewer
number of vertebrae and the possession of a silvery lateral
stripe have been placed in a separate genus (Slotephorus,
Lacépede) and the distinction would seem to be justified.
Engraulis holodon and E. capensis occur in practically the same
latitude in S. Africa, but the former in the warmer waters
‘of the Indian Ocean and the latter in the colder waters of the
Atlantic.
E. holodon has about 42 vertebrae and a silvery lateral band
and, therefore, would be placed in the genus Stolephorus
of Lacépeéde.
Engraulis capensis, n. sp.
Engraulis encrasicholus, Pappe (not L.), Synopsis of the
Edible Fishes of the Cape of Good Hope, p. 21, 1853 ; Bleeker,
Over eenige Vischsoorten van de Kaap de Goede Hoop. Nat.
T. Ned. Ind. XXI, 1860, p. 21; Castelnau, Mémoire sur les
Poissons de V Afrique australe, iB} 68.
Depth of body 62 in total length, excluding caudal, length of
head 32. Snout pointed, strongly projecting, slightly shorter
than diameter of eye which is 4? in Jength of head. Maxillary
not tapering behind, ends in angle of jaw but does not extend
to end of mandible. Gill-rakers 35 on lower branch of outer
gill arch, the longest 14 in the diameter of the eye.
63
About 44 scales in a longitudinal series, 6 in a transverse
series. Teeth present in both jaws, minute.
Dorsal with 15 rays, its origin half way between end of
snout and root of caudal. Anal with Ig rays originating
behind dorsal. Pectoral 2,\, in head. Vertebree 46.
Colour: Dark above, silvery below.
This fish closely resembles the European Anchovy (E.
encrastcholus L.), but differs from it in having teeth in the lower
jaw and a fewer number of scales in the lateral line (44 as
against 48). The number of vertebre is the same—46 in one
specimen examined—and the colour, general shape of body,
etc., are very similar.
In referring to E. antipodum of the Australian regions,
Giinther states that “ the only difference between European
specimens and those from the Southern Hemisphere is a
slightly increased number of anal rays, viz., 18-20.” He
regards it, therefore, as a variety of E. encrasicholus. The
South African specimens resemble Giinther’s specimen from
Engraulis capensis. The Cape Anchovy.
Van Diemen’s Land and New Zealand in having the additional
rays, but differ from it in the same features which mark it off
from E. encrasicholus. There seems little doubt as to the
constancy of these differences. The scales have been counted
in about half-a-dozen specimens, showing a possible difference
of one or two scales, but nothing like 48. The teeth in the
lower jaw are also well marked and rather numerous, but
smaller and readily seen with a lens or under a low power of
the microscope, the longest being about -2 mm. in length.
This fish differs markedly from the only other South African
Anchovy, which has been sufficiently described (E. holodon.
Blgr.) most obviously in the length of the maxillary, which
in that species reaches the gill opening, and in the position of
the anal, which originates below the middle of dorsal.
It is not a point of great importance as to whether early
authors, who described the South African Anchovy referred
[C.P. 5—’13.]
64
to this or to the other species, but probably the reference was
to the species near the Cape, not to the East Coast species,
and to the one which most resembles the European form. I
have therefore regarded Pappe’s, Bleeker’s, and Castelnau’s
E. encrasicholus as a synonym of the species which I have now
described under the new name of FE. capensis.
This fish is closely related to the European Anchovy,
resembles it also in its economic qualities, and there is here an
‘opening for fishery entetprise. Difficulties, however, will
present themselves in the ascertaining of its times and places of
occurrence, its capture and preparation. The attention of
fishermen and fishmerchants should be drawn to the fish, and
an adequate reward offered for its introduction to the market.
Engraulis vitrirostris, Gilch. & Thomp.
Gilchrist & Thompson, Ann. S. Afr. Museum, Vol. VI., Part
El, ps 20x (Natal).
Teeth, fine, a row on each jaw, two patches on vomer,
a and on wel anes and covering the tongue. Depth of body
3 to nearly 32 times in total length excluding caudal, length
of head 44 times. Snout 7 to & diameter of eye, W hich equals
or is slightly less than interorbital width and is 44 to 43 times
in length of head. Eyes subcutaneous; snout obtuse and
projects slightly beyond upper jaw; maxillary produced
beyond gill-opening to a little beyond the base of the pectorals ;
opercle rather more than twice as high as broad; gill- rakers
about } diameter of eye in length, 21-24 in horizontal limb of
outer branchial arch.
Dorsal 1 12; commences nearly midway between base of
caudal and point of snout ; spine short and separate from soft
rays. Pectorals ? to # length of head, reach to origin of
ventrals, which are very small, about } length of head. Anal
41; commences behind vertical of last.ray of dorsal. Caudal
nearly as long as head, forked. Scales moderately large,
cycloid; 16 scutes anterior to, 9 behind base of ventrals.
Colour (of preserved specimens), silvery, shot with gold,
back a darker shade, venules on shoulder.
This description is that of the type.
Engraulis setirostris, Brouss.
Clupea setirostris, Broussonet, Ich. dec. 1
Engraulis setirostris, Day, Fishes of India, p. 626. (See
synonymy). Gilchrist and ‘Thompson, Ann, S. Afr. Museum,
Vol. VI., Part IIL. p. 267 (Natal).
Teeth minute, present on both jaws and on palatines and
tongue. Depth of body 3% times in total length excluding
caudal, length of head 44 times. Snout about ? diameter of
05
eye, which is slightly greater than interorbital width and a
little more than 34 times in length of head, Snout obtuse,
very slightly projecting beyond lower jaw ; angle of mouth is
beneath posterior edge of eye; maxillary much prolonged,
extending to anus, lower edge finely serrated, and_ slightly
enlarged or bulging at angle of mouth. ro gill rakers on
horizontal limb cf outer branchial arch, rather widely separated
from each other and the longest shorter than diameter of eye.
Dorsal 1 14, originates midw ay Det een anterior third of eye
and base of caudal; 4th ray about *, length of head, succeed-
ing rays rapidly decrease giving the fin a triangular shape
Pectorale nearly equal length of head. Ventrals nearly 2
length of head. Anal 38, commences below or slightly behind
last ray of dorsal ; anterior rays about ? height of longest rays
of dorsal, succeeding 12 Or 13 decrease rapidly, Femaincen
subequal. Caudal forked, 1} times length of head. Abdomen
compressed ; the spiny scutes extending forward to gill-open-
ings, 14 before, 10 behind insertion of ventrals. Lat. 1. 42.
Colour (of preserved specimen), darkish above, silvery on
sides ; black venules in scapular region.
This description is that of the Natal specimen.
The South African representatives of the Sub-order Mala-
copterygii may be completed by the addition of the families :
Mormyride, Pantodontide, Kneriidze, Chirocentride, Salmon-
ide, Alepocephalide, Stomiatidee, Gonorhynchide.
The Mormyride are peculiar fresh water fishes found in
Africa, mostly in the Nile and Tropical Africa. The following
are found in the Zambesi and East Africa : Mormyrops delicio-
sus, Leach; Petrocephalus stuhlmanm, Blgr., Marcusenius
discorhynchus, Peters, Gnathonemus macrolepidotus, Peters,
Mormyrus anchtete, Guim.
The small family of the Pantodontide is represented by a
single species, Pantodon buchholzi, Peters, a fresh water flying
fish, and another small family, the Kneriide, by Aneria
angolensis, Stdr., also a fresh water fish.
The family of the Chirocentridz is represented by its single
species, Chirocentrus dorab, Forsk. found in the Indian Ocean
and Seas of China and Japan.
The Salmonidz are represented in South Africa only by
introduced species, Salmo fario, the brown trout, its variety
S. levenensis, the Loch Leven Trout, and Salmo trideus, the
Rainbow Trout.
The Alepocephalidz are represented by a species of Alepo-
cephalus, and Xenodernichthys socialis. These are deep sea
fish allied to the Clupeidee and Salmonide.
iCR 2913"
66
The Stomiatide (including Sternoptychide) is also a deep
sea family and is represented in South African seas by Mauro-.
licus amethysto-punctatus, Chauliodus sloanit, Astronesthes
boulengeri, Cyclothone bathyphila, Argyropelecus hemigymnus,
Sternoptyx diaphana, Neostonuas filiferum and Idiacanthus ferox.
Another small family, the Gonorhynchide, is represented
by its single species, Gonorhynchus greyt, occasionally found by
fishermen in their seine nets.
67
iit, INTRODUCTION OF-* MILLIONS.”
The little fish known as “ Millions ” ( Lebistes poeciliodes ) on
account of the rapidity with which it reproduces is found in Bar-
bados. It lives in pools and thrives wellin any small collection of
water, such as tanks, garden fountains, etc., so that it abounds
everywhere. It is a striking fact that the Island of Barbados
enjoys an immunity from malaria, and as this little fish feeds
to a large extent on the larvee of mosquitoes, which occur in
such collections of water, the conclusion has been drawn that
the immunity of the island is due to the fact that the mos-
quitoes which convey the malarial parasite are kept in check
by the presence of the fish, the malarial mosquito being un-
known in Barbados, though other mosquitos are found. So far
as the evidence goes it would seem that the conclusion is
justified.
This being so, it was naturally suggested that the fish might
with great advantage be introduced into the countries suffering
from malaria. It was accordingly introduced into most of the
other West Indian Islands, apparently with good results. In
1904 a ‘ Citizen’s Antimosquito Committee ’? was organised
at Honolulu for the purpose of introducing mosquito larve-
eating fish, and samples of various kinds (Mollimista, Adima,
Gambusia and Fundulus) were successfully transported from
the United States to Hawaii. No difficulty was experienced
in transportation nor in the subsequent rearing of their progeny.
The success of these experiments was doubtless due to the
similarity of conditions, especially of temperature, in the two
places.
It has proved otherwise, however, in attempts to introduce
the fish into remoter and colder regions. A consignment was
brought to London and throve fairly well in the Zoological
Gardens, though they did not increase as rapidly as was hoped.
They were kept in special tanks, as they would readily have
perished from cold in open air tanks in the climate of England.
As there were applications from several of the English Colonies
for supplies of the fish, an arrangement was made through
the Colonial Office with the Department of Agriculture of
Brabados to keep a stock, from which the fish could be supplied,
though the information obtained by the staff of the Zoological
Gardens did not indicate that the importation of the fish would
[C.P. 5—'13. |
O8
lead to the desired result. In recent years, however, ‘ Mil-
lions ” have been sent to Australia, India, Burma, and some
parts of Africa, but no success has attended these experiments.
In cases where the fish survived the journey they did not
thrive in the tanks specially prepared for their reception,
and when set free rapidly disappeared.
No attempt has been made to introduce the fish into East
Africa. In 1908, however, a consignment was brought out
for the Uganda Protectorate, but, unfortunately, perished in
the railway journey, owing, it was thought, to the excessive cold
on the Mau Plateau (bear 8,000 feet). The Administration of
Rhodesia has considered the question of the importation of
“Millions” into their territory, and it ‘‘ does not propose,
after due consideration of the value of such a step and the
probabilities of success. to take any action in the matter.”
There have been suggestions from time to time of the
desirability of importing these fish into South Africa, and Mr.
S. Goldreich recently brought the matter to the notice of the
Provincial Secretary for Natal. It was then referred to the
Cape Provincial Secretary for advice and assistance. In view
of the risks attending the introduction of animals from other
countries and the unlikelihood of any advantage to the Cape
Province, it was not considered desirable that the Cape Pro-
vincial Government should take any active steps in the intro-
duction of the new fish, but the facilities of the Trout Hatchery
at Jonker’s Hoek were offered for the experimental breeding
of the fish.
Meanwhile the * South African Anti-malarial Association ”
took the matter up and ordered a consignment from the
Department of Agriculture of Barbados to arrive about
August to escape the South African winter. |The consignment
was shipped by the ** Kenilworth Castle,’ which left South-
ampton on the 24th August, 1912. It consisted of seven tins,
all of which arrived with their contents in a good healthy
condition, some of the fish having given birth to young (the
fish 1s viviparous) on the journey of six weeks’ duration.
The fish were at once distributed to the trout hatcheries of
Jonker’s Hoek in the Cape Province, to the Trout Hatchery
at Potchefstroom, in the Transvaal, and to the Anti-Malarial
Association in Johannesburg. At Jonker’s Hoek the fish throve
well in the open-air ponds during the summer months, but
began to die off when the winter cold set in. Some were then
placed under cover with an appliance for raising the temperature
of the water and in this way a few have so far survived the winter.
At Potchefstroom the fish were placed in a carefully prepared
pond, but after a time they disappeared; the pond was
69
emptied, but no traces of them were to be found, and it was
thought that they may have been devoured by the large
frogs which were discovered at the bottom (more probably
they perished from cold). The remaining lot of the imported
fish, sent to the Pongola Rubber Estate Company’s property
in Zululand,.has also disappeared.
It does not appear, therefore, from these experiments that
the West Indian “* Millions”? can readily be acclimatised in
South Africa, and attention may now be profitably directed
to the finding of some native species of fish which may be
as useful in the extermination of the mosquito larve.
It is also to be borne in mind, as I have already stated
in a former report on the subject, that the introduction of
animals not native to the country has already been the means
directly or indirectly of injuring the native fauna, and this is an
additional reason for thoroughly testing the country’s own
resources.
A small fish known in some districts as ‘ Kurper”’
(Tilapia) has been observed (Howard) to clear the pools in
which it lives of mosquito larve. It is a hardy little fish,
stands transportation well, and appears to multiply quickly
in favourable surroundings, so that further investigations into
its habits may show that it can be utilized as a mosquito larvee
destroyer. A small species 7. philander is abundant near
Pretoria, and a few years ago I conveyed a few in a large glass
vessel to Cape Town. They throve well at the Jonker’s Hoek
hatchery, though not reproducing rapidly, probably on
account of the colder water." Plate, Lil of, this Report 1s
from a photograph of these fish in the living condition,
Fundulus melanospilus in German East Africa, Longo
Bay, Seychelles, and two other species from Longo
Bay and Zanzibar (fF. guenthert) from Victoria Nyansa and
Lake Tschaia (fF. taeniopygus) may prove useful. Species of
Haplochilus from Nyassa, Albert Nyansa, and probably in
many other regions, are also deserving of further investigation
in this connection. A small fish (Galaxias) found in the South
West of the Cape Province may prove a useful mosquito
destroyer though confined to the South Western districts of
the Cape Province.
Some investigation in this direction has already been done
in India; a number of fresh water cyprinodont fishes of
India and Burma have been kept under observation, and it
has been found that several species of Haplochilus in particular
are as hardy as “Millions” and devour mosquito larve even
more readily.
[C.P. 5—’13.]
70
The fresh water fishes of South Africa are imperfectly
known and still less is known of their habits. The great
benefits that would result from the discovery of some native
fish of similar habits to that of the Barbados fish and suitable
to this country are obvious, and such an investigation seems
a matter of necessity if active steps are to be taken in com-
bating malaria in this way.
This is a matter of course more for combined action among
the different Provinces of the Union, and the Cape Province
has less to gain than the others, though it would appear
that malaria is endemic along the whole of the Orange River,
the malarial mosquito being found at Kimberley, Barkly
West, Vryburg, and Kuruman and “much of the disease
known locally as ‘camp fever’ is in reality a mild type of
Malaria ”’ (Thornton).
The initiative in such an investigation might well be taken
by the Cape Province, and, with the co-operation of the
other Provinces might produce valuable results.
Nl 2 ae
Adinia, 67.
Agriopus, 35.
Albula, 49, 53.
Albula conorhynchus, 49, 53-
Albulide, 49, 53.
Alepocephalide, 65.
Anchovy, 48.
Anti-malarial Association, 68.
Artificial hatching (crawfish),
43, 44.|
Bank duiker, 35.
Bdellostoma, 33.
Bird Island, 25.
Camp fever, 70.
‘Cape Canning Co., 5.
‘Cape herring, 58.
‘Chanos, 49, 54.
‘Chanos salmoneus, 49, 54.
‘Chanide, 49, 54.
‘Clinus, 37.
Chirocentride, 65.
‘Clupea, 49, 57.
”
2?
”
durbanensis, 49, 59.
ocellata, 57.
Ssagax, 57.
‘Clupeide, 49, 55.
‘Crawfish, I, 3.
age, rate of growth, etc., |
3, 25, 33:
artificial hatching, 43, 44.
catches, 5.
cause of failure of com-
panies, 5.
chief markets for, 6.
close season, I, 5.
early stages, 3, 29.
enemies, 3, 34.
experimental hauls, 3, 6.
female in berry, 22.
protection
of, 2.
berry,
” ”
» largest in
Pal ey
,, smallest in berry,
20; 32.
, size at maturity, 20.
fOOd>) Ses 302
geographical distribution,
3, 25:
habits of larval, 3, 30.
history of industry, 3.
industry, I.
[C.P. 5—'13.]
Crawfish,
life history, 3, 40.
licensing of factories, 45.
male, largest, 33.
method of measurement, 6.
migrations and move-
ments, 3, 39.
observations at Marine
Laboratory, 3, 22.
polygamous habits, 22.
preservation, 3, 42.
returns, 45.
sexual differences, 3, 26.
shell casting, 24.
Size, limit) 1, 25°20; 225 44.
spawning time, 24.
frequency
of, 24, 25.
” 2
Dasjes, 36.
Dassen Island, 36.
| Dogfish, 3
Xe
| East London, 26.
Elopide, 49, 50.
Elops, 49,
Engraulis,
”
”
”?
»
”
| Etrumeus,
2
50.
_ Elops saurus, 49, 50.
| Engraulide, 49, 61.
49, OI.
antipodum, 48.
capensis, 49, 62.
encrasicholus, 47.
holodon, 49, 61.
setirostris, 49.
vitrirostis, 49.
49, 56. :
miucropus, 49, 56.
False Bay, 25.
Fundulus,
, Gambusia,
67.
67.
Gonorhynchide, 66.
Haplochilus, 609.
Hermanus
Herrings,
7)
> =)
46, 47°
Hoetjes Bay, canning factory at, 6.
Hout Bay
Horsefish,
llisha, 49,
> ” 2”?
35:
60.
Ilisha natalensis, 49, 60.
Jonkers Hoek, 68.
Klipfish, 36, 37. Rhodesia, 68.
Kneriide, 65.
Kurper, 60. Saldanha Bay, 22.
35 », canning factory at, 6.
; p Salmon, 51.
Lobster, American industry, 5. = De
? ae paige Salmonide, 65.
artificial hatching, 43. eine settee!
Sea snake, 35.
”
Megalops, 49, 52. Sea urchins, 39.
# cyprinoides, 49, 52. South Atlantic Lobster Syndicate, 4.
Mercury Island, 25. Spratelloides, 40, 55.
Millions, 67. Ay aestuarius, 49, 55.
Mollinisia, 67. Springer, 51. .
Mormyride, 65. Steenberg’s Cove, 6.
Mosquitoes, 67. Stolephorus, 62.
Stomiatide, 66.
North Bay Canning Factory, 6.
Tilapia, 60.
Turbo, 38.
Octopus, 34-
Van Riebeek, 3, 46.
Pantodontide, 65.
Phalacrocorax, 35- Whitebait, 56, 62.
Phyllosoma, 30, 40.
Potchefstroom, 68. | Zwartkops, 56, 62.
may ie
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“SPRINGER” OF THE EAST COAST OF S. AFRICA
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THE “SALMON”? OR
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TILAPIA.
A SMALL SOUTH AFRICAN FISH WHICH MAY PROVE OF VALUE AS A MOSQUITO
EXTERMINATOR.
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