BIOLOGICAL BOARD OF CANADA

SULTMARY REPORTS

of the

PACIFIC BIOLOGICAL STATION

for

1936

CONFIDENTIAL

X E. Berkeley and C# Berkeley \ ^ .^S'^yNe* 3.

Bolychagfce Wossms of the Bacific Coast*

Woacfc on the polyehaete material collected by Mr* E*C* Bart during the cruise of the Hydrographic Survey vessel, the S*S* "flta* J* Stewart", off the west coast of Vancouver island in 1954 has been continued and is Hearing completion* Some ninety species have thus far been identified in the material* .Most, but not all, of these have already been recorded from the east coast of tite Island; some are new to the west coast of North .America and others have" been recorded only from California, A-few arc new species or new varieties* A paper has been prepared on the Spionidae of the west coast of Canada •and is published in the current issue of tho Annals and Magazine of Natural History* It is intended that this shall be the first of a sorios of such papers, each dealing with a family, or a fow families, of polychaeta* The usual identifications and reports on material sent by other workers on the coast have boon made during the year*

C* Berkeley No* 2

Harvesting of Eel-grass seed*

Some experiments on the harvesting of eel-grass seed were successfully carried out during the summer on behalf of the National Parks Branch of the Department of the Interior, Ottawa♦ The Department is anxious to determine whether plants grown from seed harvested from the West coast eel-grass are Inrrmme to the disease which has ravaged the beds on the East coast* Attempts to collect sufficient seed direct from the beds last year proved, a failure, due to its being shed as soon as aipe* TftrFa. year the flowering shoots were collected whilst the seed was forming and kepli in tanks of running sea-water for some weeks* The seed continued to ripen and was shed in the tanks and a pint or so of material was collected in this way* This seed has now been sown on tho Atlantic coast*

G. Clifford Carl No* 5

Shawnigan Lake

During the summer of 1936, a further examination of Shawnigan lake was made* In August, 1935, it was found that thoro was definite thermocline between ID and 15 metres and the surface and bottom showed a difference In temperature of over 13° C* Tho water below the thermodihe was decidedly acid, showing a range in pH reading from 5*0 at tho bottom to 6*4 at 15 metres* The surface water was only slightly alkaline* The low oxygen content of the bottom water suggested a state of depletion in late summer* G. Clifford Carl * No* 3

In 1936 somewhat similar conditions were found* The bottom water was slightly lower in temperature and th& surface water slightly higher*, The thermocline was present but at a lesser depths viz*, between 5 and 10 metres* The pH readings, were approximately the same as those of the previous year while the oxygen content in the- dacp witor was less© The plankton crop was very abundant but the higher aquatic plants were scarce* The lake is relatively poo:: in both kind3 and numbers of bottom organisms*

TABLE - Showing Physical and. Ch&Dieal Conditions of Water Samplesr. Shawnigan Lake, August 4? 195$© °

Depth Temperature pH --vgoii Saturation Alkalinity m9 C° W.: % PaPoiiu CaCO^

0 Aj^oI 7*4 ?,.se: 85 5 20e8 7*5 13*8 10 8*8 15 20 6095 6-4 .3->f.Vi 43 14

The lake contains a fairly Ir,;-^' population of the eastern catfish, Ameiurus nebulo'sus, introduced about thirty years ago* In 1896, 1P1E5,00C fry of the eastern whitefish. Corcgonus cl>.ipc:.'iformis - were introduced but there are no records of the subsequent capture of Individuals of this species. A fish cultural prograri for the; production of trout and coho salmon is being developed9 based partly o:i the results of the two examinations c.

G* Clifford Carl No* 4

Lakes Investigation»

m connection with a resto?.Io.ii3 programme undertaken by the Provincial Game Department, thres small 1aires in the southern portion of Vancouver island were examined during the s-joL-cr.* of 1936o

Prospect Lake^ July 88,, 1936 > Prospect lake is a snail body of water one mile long and one-half mile wide, covering about 300 acros and situated at an elevation of 154 feet about one mile south of Observatory hill in tho Lake district of Saanich peninsula* It has a maximum, depth of 10 metres, a depth which appears to be uniform over a wide area* A series of temperature readings and water samples taken at a mid-point in the lalco showed the presence of a well-marked thembcline between 5 and 7 metres* Coincident wri;h ihf.s Gratification was a tendency to G* Clifford Carl No. 4

depletion of dissolved oxygen together with an acid condition in the bottom layer of water* A vortical haul with the large plankton net showed a not unusual crop of plankton* A tow through a water-lily bed revealed the #^ presence of a bloom of the bluo-^reen alga, Gloeotrlohia ochinulata* The * dominant Vegetation consisted of water-lilies CNuphar), wator buttercup (Ranunculus) and reeds CScirDufe}» Associated with them wore molluscs (Physa, Lycmaea and Anodonta), leeches and aquatic insect larvae* The following fish wore observed: stickleback CGasterosteus aculoatus), bullhead (Cottus asoerj and sunfish CEupomotus gibbosus)*

Thetis Lake, July 29 » 1936* Thetis lake is a small body of water situated about one-half mile inland from the head of Esquimalt harbour at an elevation of 158 feet. The lake consists of two separate portions formed by the artificial flooding of two small valleys*, The upper or westerly portion overflows into the lower or easterly portion and is reached from the latter by a very short portage. The west portion covers a larger area but is shallower in depth, attaining a maximum of 4 metres only in two or three snail areas 0 The temperature of both bottom and top wator was high, being 19.6° C* and 24*9° C* respectively. The amount of dissolved oxygon was abundant except in tho lowermost layer of water whore it was reduced to 20 per cent saturation and was accompanied by a slightly acid condition. An average crop of plankton was present and bottom organisms were represented by chircnonid and tipulid larvae* Mature and seedling water-lilies (Nuphar) wore very abundant. The east portion of the lake attains a maximum depth of 9 metres but only over a snail area<> Normal water conditions prevail except over this deepest area where a total lack of dissolved oxygen was found at the bottom* A good crop of plankton was present and also a variety of bottom forms except in the oxygon-depleted zone. Pondweods (Potamogoton spp*] were very abundant throughout the shallower parts of the lake.

G* Clifford Carl No. 5

Distribution of Cladocora and Copopoda in British Columbia*

During the summer of 1936 over thirty sets of collecting equipment were sent out to fishery officers and others in order to obtain plankton samples from various parts of the Province. The material received to date, together with that of previous years, represents collections from more than 200 lakes and ponds, mainly from tho following areas: Vancouver island. Queen Charlotte islands, lower mainland coast, Okanagan, Kanloops, Cariboo, Qnesnel, Fort George and Dease river. Collections in other districts are also being made. The examination of the material on hand shows the presence of many organisms hitherto unreported from British Columbia. In general, the cXadocera are similar to those found in other parts of North .America and Europe, being characteristic of north temperate regions. The copepods are similar in this regard also, except in the case of those of the genus Diaptomus* The copepods of this group have long been considered unique, in so far as the North American species appeared to be restricted to this continent while European G* Clifford Carl NOe 5 species of the same genus were found only in the Old World. However, the present study and other recent investigations indicate that several species are common to both continents, suggesting a two-way migration by means of #^' ancient land connections* The presence of certain European species in samples from some of the northern interior lakes of British Columbia confirm this theory and it is hoped that further collections will provide more valuable data.

G. Clifford Carl Na& 6

Distribution of Crayfish.

Western crayfish (Genus Potamobius) are found in British Columbia in the following areas: Kootenay district (Slocan lake)I Similkamoon district (Kettle river), Okanagan (Okanogan lake)^ lower mainland (Burnaby lake), lower Vancouver island (Beaver lake, langford lakeP Shawnigan lake) and west coast of Vancouver island (Sechart, Kennedy lake and Nootka island)* Collec tions from some of these localities indicate that at least two species are present: Potamoblus klariathensis Stizipson in the interior of the Province and on the west coast of Vancouver island., and Potamobius trowbrldgli Stimpson (P. loniusculus Dana ?\ on the lower mainland and lower Vancouver island* Although their distributions are remarkably discontinuous they appear to be native to the Province except in the case of those found in the lakes of tho lower Island, particularly Shawnigan lake. The presence of crayfish in tho lat'eer lake seems to be the result of an introduction of a few individuals" from the state of Oregon by the late Judge G. Hunter some thirty years ago* It is hoped that further collections will help explain the peculiar distribu tion of these Crustacea and that further investigation will reveal their status in relation to other organisms, particularly commercial and game fishes0

W.A. Clemens and L.S„ Clemens No. ?

Contributions to tho Life History of tho Sockeyo Salmon (No, 21).

During the year 1935 the runs of sockeyo salmon to the four main river systems of British Columbia presented some unusual features. With the exception of that to Rivers inlet, the returns were comparatively small. The pack on the Eraser river was 117,499 cases and., while smaller than its cycle predecessor, nay be considered rathor large in respect to the escapement of 1931. The total run was undoubtedly smaller than that of 1931 but the escapement was slightly greater. The 4g age-group comprised 71 per cent of the run, the 5g age-group 23 per cent and the remaining age-classes (&3> 3l> 4i and 32) 6 per cent. Tho 5g's were not only particularly abundant W*A. Clemens and L.S. Clemens No. 7 they were ^specially large as well. The sexes were represented by 48 per cent males and 52 per cent females. The run to Rivers inlet was large, producing the second largest pack on ^ record (135,038 cases representing approximately 1,755,000 fish) and a largo escapement as well.. The 4g age-group constituted 56 per cent of the run and the 52 age-group 41 per cent. There were no unusual features in regard to size or sex distribution. The expected large run to the Skeena failed to appear. The pack was but 52,879 cases and only about half that anticipated. Moreover, the escapement, while reported as good, was apparently not such as to indicate that the low pack meant a corresponding increased escapement. The age-groups wore represented as follows: 42 - 49 per cent; 52 - 31 per cent; 53 - 18 per cent; 6

W*A. Clemens, R.E. Foerster and C. McC. Mottley No* 8

A Transplantation of Sockeye Salmon to the Nanaimo River System.

In 1932 the Nanaimo Board of Trade requested the Department of Fisheries to make an attempt to establish a run of sockeye salmon to the Nanaimo river system and the Pacific Biological Station was requested to make a general survey of the water area. During the summer of that year Dr. llottley, assisted by Mr. G.C. Carl, made a brief survey both of the river and the three lakes. He reported that the physical conditions, as far as could be determined from a short summer investigation, seemed to be reasonably suitable for sockeye salmon production but that there were two adverse biological factors, namely, an apparent paucity of plankton and the presence of a rather large population of trout* The recommendations were submitted that if an experimental introduction were to be made: (1) the young fish be held in retaining ponds until they reached a size suitable for marking and liberated in the First lake after removal of two fins; (2) a screen fence be installed in the outlet from the First lake to determine if the marked fish went to sea and if so, in what numbers. These recommendations wore based in part upon the discovery of kokanees in the lakes and the possibility of the introduced sockeye remaining in the lakes and merely adding to the population of kokanees. Furthermore, there was the possibility that small numbers of adult sockeye annually enter the Nanaimo river since some streams of the south-eastern section of Vancouver W.A. Clemens, R.E. Foerster and C. HcC. Hottley No* 8

island, example, Cowichan river, are known to have such migrants. Whether such fish are stragglers or whether they are the product of the kokanees of the various lakes is not known. JF* The Department was unable to adopt the above recommendations because of lack of funds but it decided to make an introduction of eyed-eggs. Accordingly one million eyed-eggs from Rivers inlet were planted in streams tributary to First lake in the spring of 1933 by Mr. F.A. Tingley. Because of their interest in the introduction, the writers suggested to the Department the desirability of an attempt to determine if yearling sockeyo left First lake for the sea in the spring of 1934. Following a discussion of * the situation, Mr* W.F. Baxter was detailed to install a trap at the outlet of First lake but though operations were carried out from March 13 to May 26, no sockeye were token or observed. This autumn, 1936, the Department made arrangements for the Chief of the Nanaimo Indian Reserve to oporato a gill net in tho lower section of the Nanaimo river during July, August and September. Three male sockeye were taken, one of which was a five-year-old fish and thorefore not the product of the transfer. A vigorous patrol was carried out on the upper section of the river system but failed to disclose the presence of any sockeye. The only conclusion to be drawn at the present time is that the introduction has failed to produce a run of four-year-old fish. Thero is & vory scant possibility that the fish remained two years in the lake and may return as five-year-old individuals in 1937. The apparent failure of sockeye to return to the Nanaimo lakes cannot be explained and owing to the nature of the experimental introduction the place 2n the life-history where the "break" occurred cannot be determined. The possibilities are: (1) that tho eggs failed to hatch; (2) that the young fish were destroyed by trout, coho and coarse fish; (.3) that climatic conditions wore such that seaward migration was not brought about; (4) that the adult fish strayed to other streams. The fact that no migrants were observed at the outlet of First lake would seem to point to a failure in the fresh water portion of the life cycle* D.C.B* Duff No* 9

Fish Diseases.

Furunculosis* Due to lack of funds, together with the unsuitability of the University tanks for maintaining trout» it has not been possible to carry out Recommendations No. 1 and No. 2 contained in the Pathologist7s summary report tox 1935. However, the third recommendation - to investigate further the characteristics and pathogenicity of the variants of Bacilius salmonicida - has received soma attention* I ati now able to report that it is tho MGT" variant (probably corresponding ilo. tile 6 or smooth variant in othor bacterial species) Which is the pathogen. This strain id capable of producing the typical disease in goldfish* 2ho ,;C0M variant (probably corresponding to the R or rough torn of othor species) is ihcapabio of producing tho disease. Tho G typo variant (corresponding to the t "typos of Hadloy, belvos and KLimok for the Shiga dysentery bacillus and othor specios) is also non-pathogenic. Considerable serological work has been done :'.n ordor to determine the antigenic relationships of the. variants mentioned. Cliis work is still in progress J and was developed with review to investigating tho possibilities of producing some prophylactic product, in tho form of a vaccine or like preparation, from one of the variants. In my opinion there is a possibility of obtaining such a product, which night bo given in food to -»*ory young fry, and which might produce some degree of immunity to natural :.iifection. There is much controversy as to the efficacy of orally administered vaccines in tho human, but thorc are certainly enough claims of a positive result to warrant a trial of this method with fishes. Moreoverr antigcnically speaking, ny experiments have shown that:

CO variant ~ GT variant •> X where X represents extra cntigan prosent in CO but not in GT

Translating this into the classical terminology, for B* salmonieida R(avirulent) « S^iruiont) * X

That is, without reforonce to the possible presence of tho Vi antigen of Folix. This indicates that the avirulent strain possesses all tho antigens prosent in the virulent strain {plus othersf*- From this it may bo surmised that a vaccine preparation (either live or dead) made from tho avirulent strain should protect against invasion from the disease-producing strains* jjron the date of the last summary report, no evidence whatever of furunculosis has been obtained from tho Stanley Park hatchory.

Fin Rot. During September-October.. 19c^: this disease (etiology unknown) appeared in some of the tanks of the Stanley Park hatchory. Tho losses wore moderate, and wore confined tc tho stoolhcad trout. One tank especially (No. 4) was affected. Bacteriological cultures wore made from dorsal and caudal fin losions, but no results were obtained to suggest that tho disease was primarily bacterial in nature. It should be mentioned that those cultures woro completely negative for B. salmonicida. Due to the unknown nature of the disease no rational therapy could be rocommondod* Rcpoatcd salt baths seemed to relievo the condition slightly. D.C.B. Duff No* 9

Octomitiasis. In February, 1936, this disease was recognized among tho Kamloops and steelhoad trout at Stanley Park hatchery and was confirmed by microscopic examination. Although the causative agent of this disease is known, tho way in which tho protozoon carries over from year to year in the hatchery wator supply is quite unknown. It is obvious that in this knowledge lies tho key to control.

Recommendations:

Furunculosis* Generally speaking, a stage in the investigation of this disease in British Columbia has been reached when further useful results cannot bo hoped for without tho establishment of a more oxtensivo programme. Tho progress sc far may bo summarized as follows: (a) Tho prosonco of tho disease has boon established at various times in the Elk river, in tho hatchory at Smith falls9 in the hatchory at Stanley^ park, and in certain lakes and^ streams near Cranbrock. In the last locationJ the disease as such was not presont, but tho cutthroat trout were acting as carriers of tho specific bacillus. (b) Evidence indicates that the introduction of the disease to the Stanley Park hatchery was due to the transfer of infected eggs from Cranbrook to the hatchory. The origin of tho epizootics in the Elk river and at Smith falls is unknown. r(c) Grave doubt exists that the acriflavine treatment of trout oggs is an adequate moons of preventing the spread of infection through distribution of egGS. (d) Pending proper proof for or against acriflavine disinfection, the J importation of gone fish oggs from doubtful sources outside the Province^ and tho distribution within the Province cf eggs from aroas known to be infected, has been prohibited. (e) Extensive studios have been made on tho longevity of the causative bacillus in water. These have shown that under certain conditions tho survival time of tho organism is over 60 days, rather than for tho short periods of 3 to 5 days reported by tho investigator for tho Furunculosis Committee of Great Britain. (f) The dissociative abilities of B. salmonicidq have been demonstrated for the first time, and the possibility of developing an oral vaccine for prophylactic purposes has been indicated. The following problems, which must be solved before final and logical control measures can be adopted, are incapable of solution under present conditions of time and equipment: (1) Are steelhead and Eomlocps trout susceptible to furunculosis as a disease; if so, under what conditions? Are these fish capable of acting as healthy carriers, as has boon proved in tho case of cut throat trout? (B) Is acriflavine disinfection of eggs actually offactive in controlling the spread of the disease? (3J Can a prophylactic treatment be developed which may bo givon hatchery fry as soon as thoy are able to eat, and which will protect against subsequent or current exposure to the virulent bacillus? D.C.B. Duff No* 9

Experience has now shown that the answer to questions of this type can only be obtained by the use of a properly equipped experimental plant, under the year-round care of a practical fish culturist who is capable of absorbing^ and using special training in the principles of bacteriology and of infection, and who would carry out work undor tho direction of the Pathologist. Further more , each of tho above problems involves tho lone term holding of experimental stocks under special conditions; it would thus be necessary to allow for the continuous operation of the experimental plant for a period of at least 5 years.

Other Diseases. If hatchery culture of British Columbia trout is to bo continued, it would bo highly advisable to make a scientific attack on the diseases (other than furunculosis) which are often responsible for heavy losses. Tho chiof of those is Octomitiasis. Although the causative protozoon of this disease can bo recognized, little is known about its means of survival and transfer. Very heavy losses havo boon recorded from this disease. Other minor conditions include "fin rot", "popoyo", and fungus diseasos (all of which have been noted in British Columbia). These may or may not cause heavy loss depending on conditions. It is my opinion in respect of these diseases, as of furunculosis, that field work and laboratory observations have reached the limit of their usefulness. Further progress in control can only be attained by controlled experiments in infection, treatment and prophylaxis, and such conditions can only bo obtained in an adequate experimental plant. It is therefore recommended, if investigations with a view to controlling diseases of fish aro to bo continued, that provision be made for the equipment and personnel necessary to obtain conclusive results.

E. Kuitunen-Ekbaum No* 10

Fish Parasitology.

The following is a brief summary of the work carried out on fish parasitology during the last two years:

Acanthocephala (Thorny-headed Worms)* During June, July and August of 1934 a number of species of Acanthocephala were collected from both fresh-water and marine fishes in tho neighbourhood of tho Pacific Biological Station. Echinorhynchus gadi, the common representative of the Acanthocephala in the gadids and salmonids of both coasts of tho North Atlantic was found numerous in all five species of Oncorhynchus, The occurrence of this parasite is strictly seasonal in Oncorhynchus s though it occurs at all times in the numerous species of fish on the oast coast of Canada. For this reason it has hitherto been overlooked in the Pacific salmon by previous workers. The life history of E. gadi from Oncorhynchus has been studied in some detail. The amphipod, Cyphocaris challengeri, has been found to be the inter mediate carrier in which the parasite reaches the infective stage. This, liberated from the ingested amphipod in the stomach of the fish, soon establishes itself in tho lower part of the intestine to which it becomes attached by the hooks of the proboscis. E* Kuitunon-Ekbaum jjo# 10

Evidence has been obtained indicating that some othor species of Crustacea may also serve as the intermediary host for this parasite* Sovoral othor spocies of Acanthocephala have been found parasitic in #* shoro fishes in tho neighbourhood of tho Biological Station. One of thoseJ v which occurs in the flounders Platichthys stollatus and Lopidopsetta bilineata will shortly be described under tho name Echinorhynchus lagoniformis. Attempts are at present in progress to trace the lifo history of this parasite.

Nematode (Round Worms). Work on tho life history of the dracunculid nematode Philomotra americana, subcutaneous parasite in the flounders Platichthys stollatus and Lepidopsetta bilineata, is being continued this winter. Tho shore Copepoda, Ectinosoma molaniceps and Cyclopina gracilis, have boon found to be intermediate hosts of this parasite. Numerous attempts to infoct'othor shoro invertebrates with the first phase of tho parasite have failed* Many observations of other parasites of thoso flounders have been recorded for tho future work. At prosont attention is being concentrated on the different phases of tho development of 3?. americana in its succossive hosts. Much attontion has been given to the migration of the parasite in the tissues of the fish which is hoped may throw some light on tho parallol problem in related species. Tho most noted of those is the Guinea-worm of man. A description of Cystidicola walkeri, a new species co31ected from the swim-bladder of Oncorhynchus kisutch in 1934, was published in Zeitschr. Parasitenkunde, B*7.H.4, 1935, and a note on tho three species of the genus Cystidicola which occur in Canada, in tho Canadian Field Naturalist, vol. 501 no* 1, 1936* Further work on the development of £. walkeri is at present in progress.

C.R. Elsoy No. 11

Propagation of tho Japanese Oyster in Ladysmith Harbour from Stimulated Spawning*

In 1932, 1933 and 1935 stimulation of spawning was practised in Ladysmith harbour with tho result, in each instance, that larvao in tho early free- swimming stages bocamo plentiful in the plankton by mid-summor«> In 1932 many of thoso larvae survived and produced a set of definite economic value; in 1933 only a few larvae survived and only a light, widoly scattered set was produced; in 1935 all larvao died at a very early stage. In 1930, 1931 and 1934, on the othor hand, no stimulation of spawning was practised and no larvae, even in tho early stages of development, were taken in the plankton. From the above results it was concluded that stimulation of spawning early in the summer, though not necessarily productive of a rsotr, groatly increases tho possibility of its occurrence. In order to further tost tho feasibility of the practice and to obtain more information concerning the factors affecting larval development, experimentation was continued in 1936, Oysters wore stimulated each day in tho interval from July 18 to 22. At the ond of this period, from 1 to 2 million individuals, contained on approximately 3 acres of tidal bottom, had completely discharged their spawn* C.R* Elsey No* 11

No further stimulation was practised and no additional spawning occurred until August 1* Consequently an excellent opportunity was afforded of following the development of the larvao and assessing the intensity of the 'set* resulting therefrom* Each day from four to six hours after spawning, larvae in the earliest swimming stage (roughly 6/100 mm. in longth) became plentiful in tho plankton* Subsequent measurements at daily intervals.showod those larvae to be increasing regularly in longth. By August 3 from 15 to 20 por cent of the larvae in water samples had attained a longth of 29/100 mm* and developed the prominent eye-spots indicative of approaching setting. Spatting commenced on August 4 and was completed by August 12. Tho nowly-aitached spat averaged 3/10 mm. in length* The average daily water temperature from first Spawning, July 18 to first spatting, August 4, was 72.2° F* .Kaxinun and minimum temperatures wore respectively 74.7° F. and 69.8° F. Salinities of high tide water ranged from 24 to 28 parts per thousand. Shells suspended in wire bags from floats adjoining the oystor bods wore used to determine tho intensity of spatting• Two cubic foot of those shells (a volume equivalent to one standard seed case-from Japan) selected at random from the content of 10 bags, bore 20,153 spat (an average of 37*6 per shell). Tho count por case, of seed from Japan, usualljr ranges from 10 to 20 thousand. It is clearly demonstrated that for tho season in question, tho oysters by mid-July wore thoroughly ripe and only required a suitable spawning stimulus to induce thorn to produco healthy larvae» It is shown further that a relatively small quantity, of spawners can, in such a body of water as Ladysmith harbour, produce a sot heavy enough for all practical purposes, providing hydrographical conditions are suitable for larval development.

C.R. Elsey No* 12

Natural Spawning of tho Japanese Oyster in Ladysmith Harbour in 1936.

Under the influence of unusually high air temperatures in the period from July 28 to August 5, wator temperatures at high tide on five succossive days beginning August 1, exceeded 73° F. On each of thoso days natural spawning occurred of large tracts of oysters. Although no accurate estimate can be made of the number of oysters contributing spawn in this poriod, it may bo assumed with safoty that it exceeded by at least ten times9 the number artificially stimulated between July 18 and 22* From August 1 to September 5 larvae resulting from this natural spawning were present in the plankton. After August 12 their numbers diminished very rapidly. Setting commenced on August 22, showing that the minimum time required for larval development was 22 days* Daily water temperatures from the date of first spawning to the dato of commencement of setting averaged 70° F*, two degrees lowor than for the poriod from July 18 to August 4 in which a portion of the larvae from stimulated spawning completod tho free-swimming stages of development ♦ C.R; Elsey No* 12

Throughout the interval from August 22 to September 5j daily spatting occurred. At the end of the period a set averaging roughly 20 spat per shell had accumulated on wire bags suspended from floats located in the same ^" position as those used for the collection of spat from earlier stimulated spawning. Although the number of oysters spawning naturally was, by conservative estimate, ten times greater than the number stimulated to spawn at an earlier date the' resulting concentration of spat was only slightly more than half as great* It is evident, therefore, that the larvae resulting from natural spawning suffored a much higher rate of mortality than these produced as a result of stimulated spawning. It may be concluded either that conditions were iess. suitable for larval development following natural spawning or that the sexual products were detrimentally affected as a result of the delay in spawning. More complete analysis of hydrographical data and further experimentation on larval dovolopment under controlled conditions are required before a satisfactory explanation of the difforenco in results can be given.

C.Ri Elsoy No* 13

Devices for Spat Collection and Methods of Exposing Cultch.

Whole oyster shells, though universally used for cultch, are by no moans ideal for the purpose. In tho first place, because of their relative indestructibility in water, they tend to hold tho spat together in clusters with tho result that oysters of poor shape are produced. In the second place, thoy are too heavy in proportion to the 'settingr surface which they provide to be used economically for suspension from floats. In an attempt to overcome those disadvantages, shell was broken into small fragments and attached to a variety of retaining surfaces, so that it could be advantageously exposed for collection of spat. Burlap. Four hundred yards of light grade burlap, 9 inches wide, were run through boiling marine pitch or through roofing asphalt and sprinkled with coarse broken oyster shell which was immediately pressed in with iron rollers. The resulting product was cut into convenient lengths and suspended in a variety of ways from floats or laid out on shelled bottom. Cardboard Sheets. Four thousand sheets of light cardboard, 12 inches square, wore prepared in tho same manner as the burlap. The greater portion of these was threaded on wire in groups of twenty or more, using perforated oyster shells as separators, and suspended from floats. Some of the remainder were laid out on shelled bottom and others mixed with wholo shell in large wire bags for suspension from floats. Asphalted Roofing Folt. Strips of a standard light grade commercial product, 9 inches wide and 24 feet long, were treated with hot roofing asphalt and broken oyster sholl. Subsequently tho prepared strips were crimped into folds 12 inches wide and threaded on wire. Perforated oyster shells were used to separate tho folds. The completed units wore suspended from floats or laid out, on edge, on shelled bottom. C.R. Elsey No* 13

Roofing material prepared by tho manufacturer in the routine manner, except that coarse broken oyster shell was used as a surfacing material, was also employed* Cardboard Egg-case Fillers. Standard fillers dipped in hot marine pitch and hoatod with oyster sholl woro bound into bundles of 20 or more with chicken wire and suspended from floats;

Results. Sots comparing favourably in intensity with those obtained under like conditions with whole sholl wore collected on all of the prepared materials. Although in some instances the concentration of spat exceeded 1,000 to the square foot, individual sholl fragments rarely bore more than two or three spat* Two months after sotting when tho young oysters had attained an average longth of ono half an inch they wore readily separated by tearing or shredding tho retaining material, and could be spread out on hard bottom. The prepared collectors proved to be particularly well suited for suspension from floats. It was found that, for each unit of buoyancy approximately ten times greater sotting surface was attainable with tho card board squares, for instance, than with whole oyster shell in wire bags.

C.R. Elsoy No. 14

Tho Effect of Stimulated Spawning on the Conditioning of Japanese Oysters.

Japanese oysters which fail to discharge their spawn or discharge it late in the summer are usually in poor condition throughout most of tho winter with the result that the length of tho marketing season is seriously curtailed* With tho co-operation of the Crescent Oyster Company, the oysters on a large tract of tidal bottom on Boundary bay were stimulated to spawn between July 22 and 25 at an approximate cost of $20.00 in labour and equipment. The remaining oysters did not spawn until late in August. Consequently it was possible to determine the effect of early spawning on condition. It was found that tho oysters which wore forced to spawn in July were in excellent market condition by tho first of September, whereas those which rotained their spawn until late in August woro still thin and unsuitable for marketing in November. It is clearly demonstrated that stimulation of spawning with a view to improving the condition of oysters is economically feasible and that it should bo rogularly practised by all oystor growers on the Pacific coast.

tip* CiR* Elsoy No# 15

Decreased Mortality among Eastern Oystors Imported to Boundary Bay.

Tho rate of mortality among Eastern oysters imported from Connecticut 0^ to Boundary bay, in tho seasons 1930 to 1933 inclusive, has varied from 40 to 50 per cent in the poriod between planting and harvesting. In the face of such a high rate of mortality there is no profit in the undertaking. Investigation into the source of supply revealed the fact that the oysters designed for shipment to the Pacific coast wore dredged from deep wator. It was recommended that since plantings in Boundary bay are made on high ground exposed for long periods at low tido, oystors be obtained from similar ground on tho Atlantic coast; In the seasons 1934 and 1935* oystors were obtained by tho Crescent Oyster Company from high ground and planted out in Boundary bay on the ground previously used for oysters from deep water; It was found from counts of dead oystors on experimental plots and from comparisons of tho numbers of oysters planted with the numbors harvested that tho rate of mortality in each of tho two seasons was slightly loss than 10 por cent* As a result of this striking decrease in rate of mortality, a good profit was made from tho sale of the oystors. Continued observations will be made to determine definitely whether tho results are influonced by unknown factors. In tho meantime, in viow of the fact that oysters from high ground are equal in quality to thoso from doop water, it is recommended that only tho former type be imported. R*E* Foerster No. 16

The Downstream Migration of Young Sockeye Salmon from Cultus Lake. 1936. During the spring of 1936 (Iferoh. 15 to.iftine 6) a total of 502,983 seaward-migrating sockeye were counted passing out of Cultus lake. Of those, 501,563 were yearlings and 1,420 were two-year-'oldsi The yearlings resulted from the planting of o1 $596*000 eyed eggs in the gravel beds of streams about Cultus lake in the string of 1935 and represent approximately 4*93 per cent of total eggs available in the spawning run, 6*7 per cent of eggs available for stripping and 9;0 per cent of total eggs planted* Account must be taken, however, of the fact that some weeks after the plantings were made a period of drought so reduced or cut off entirely the flow of water in two of tho streams planted that the great majority of the eggs placed therein were lost* in tho two creeks affected a total of 2,560,000 eggs had been planted* The.remaining plantings, comprising 3,030^000 eggs, were thus chiefly responsible for the young sockeye yearling** counted and, on such a basis, the percentage survival to the yearling stago amounts to 16*6 por cent. Comparison of the above results with thos'e of preceding tests of eyed egg planting may be made as follows:

Year 19*38 1933 1934

Survival to the seaward Based on Based on migrant stage as a bercent&ge original successful of: planting planting

Total eggs 0.95 3.6 4*9 9*0 Eggs available for stripping 1.44 4.7 6.7. 12.4 Eggs planted 1.64 5.5 9*0 16*6

For the 1934 test tho percentage survival is notably higher than previous experiments, particularly if due regard is had to the unavoidable effect of drought* The factor seemingly chiefly responsible for the increased returns appears to be the campaign of predatory fish destruction undertaken in the spring of 1935 and actively pursued thereafter. Confirmation of such explanation is being awaited.

R.E* Foerster No. 17

The Marking of Soaward-oigrating Young Sockeye in 1936.

During the spring of 1936 all of tho sockeye migrants released from the counting pens at Cultus lake, 497^600 woro marked by the removal of both pelvic fins in order that the percentage return from the sea might be determined. Previous experiments (now in press) havo established that the recoveries of marked adults represented from 3.5 to 4.1 por cent of the marked migrants* A differential mortality among marked fish of approximately 62 per cent was indicated, thus disclosing that tho probable return from the soa under normal circumstances would approximate 10 per cent. R.E* Foerster No. 17

Confirmation of these findings is anticipated in the second series of tests now under way in which 255,000 migrants were marked in the spring of 1935 by removal of the two pelvic and the adipose fins and 497^600, as here ^ reported, in 1936. The chief returns are expected in 1937 and 1938 at which times campaigns of recovery of marked adults will be made in the fishing areas and at Cultus lake*

R*E* Foorster No* 18

The Destruction of Fish Predatory upon Young Sockeye Salmon in Cultus Lake*

To ascertain what portion of tho 95 por cont loss among young sockeye during their year's residence in Cultus lake is caused by predatory fishes and to what extent a reduction in tho populations of predatory species may reduce this high mortality, a program of predatory fish destruction was initiated during the summer of 1955. Three methods of capture were utilized, gill netting, seining and bait line setting but the latter, practised only during the winter of 1935-36 when netting was rendered inadvisable by reason of the presence of spawning sockeye in the lake, was the least efficient and was stopped* Seining was resorted to principally during the summer months when the young coarse fish populated inshore waters. Gill netting was conducted throughout the season, as far as practicable, but, as intimated above, was not carriod on during the winter of 1935 (October 16 to February 26). Tho catches to October 31, 1936, of each specios in the three types of gear are as follows:

Date Squawfish Char Trout Sucker Sculpin Coho Sockeyo

Gill Nets - jjSay 28/35-0ct* 15/35 2,502 230 224 976 42 43 81 Feb. 27/36-0ct. 31/36 5,301 222 549 1,001 228 208 579 Bait Lines -> Oct. 16/35-Feb. 26/36 125 1 4 6 69

Total Large Fish Captured 7,928 453 777 1,983 339 251 660

Squawfish Trout Suckers Sculpins Coho Dace Sticklebacks Seines - Summer of 1935 3,957 2 25 389 13,935 3^144 Summer of 1936 8,667 136 336 2,066 748 21,912 12,?81

12,624 138 361 2,455 748 35,847 15,925

As indicated by Dr. Ricker in his reports on stomach analyses of predatory species, the squawfish, char, trout, coho and possibly sculpins are tho species of particular importance limiting tho survival of young sockeye* R.E. Foorstor No* 18

As intimated in other summary reports, thorc is evidence not only that the destruction of predatory fish, as tabulated above, has materially reduced tho lake population of squawfish, char and trout but also that there has occurred an appreciable increase in the percentage survival of young sockeye in the lake at the present time* valuable experience is being gained in the netting and seining operations and special attention is being given to tho possibility of developing a practice which may be adaptable to other bodies of water in British Columbia,

R.E. Foorster No* 19

Assessing the Results of Predatory Fish Destruction in Cultus Lake.

Attention has been directed in a preceding report to the probablo very beneficial effects of reduction of predatory fish populations upon the survivors of tho eyed egg planting of 1934-35. The percentage survival to the seaward migrant stage was notably increased. To assess the value of the work still further, natural spawning of sockeye was permitted in the fall of 1955. At that time 10,032 adult females were released to spawn in the lake, providing, on the basis of an average egg content per female of 45067 eggs, a presumed deposition of 40.800,000 eggs* The product of this natural spawning will be counted in the usual way in the spring of 1937 and the increase over previous years9 natural propagation tests determined. To make the assessment more accurate and to establish more definitely the decrease in fry and fingerling mortality in the lake resulting from tho predatory fish destruction it is proposed to conduct sockeye fry distribution in Cultus lake in tho spring of 1937. Through tho generosity and close co operation of the Department of Fisheries which is conducting the hatchery operations, artificial propagation is at present under way at Cultus lake and no spawning salmon arc being allowed into the lake. Next spring the fry obtained from tho ogg collection will be distributed in the lake. In this way^ knowing the extent of the fry distribution, the survival in the lake itself can readily be determined and any increase in percentage survival can be more definitely attributed to the destruction of predatory fish.

R*E* Foerster and W.E. Ricker No. 20

Indicated Trends in Predatory Fish Populations in Cultus Lake as a Result of the Destruction of Predatory Fishes.

In an effort to determine the effect of the fishing effort during 1935 and 1936 upon the populations of predatory species fished, preliminary tests jfP^ have been run and the data obtained from the catches analyzed* These may bo briefly summarized as follows: R.E* Foerster and W.E* Ricker No. 2C

A. Comparison of Catches of a Gang of Ton Nots, 1934-1936. In 1936 a gang of nots of ton difforont meshes, arranged in the same way as a similar gang in 1934, was set on the some datos and in the same 0^ situations as in the latter year, on nine occasions between July 19 and October 30. Although the efficiency may not have boon oxactly tho same in the two seasons it is believed to have been approximately so as tho gang received the same treatment in the two seasons, and was in generally about the same condition. Tho catches woro as follows:

Year Char Squawfish Trout Suckor Coho

1934 25 31 6 22 5 1936 3 11 3 2 0

In no case is the 1934 catch less than that for 1936 and in three cases - char, squawfish and suckor - it is significantly greater, in the statistical sense. A somewhat wider comparison can be obtained by using an additional number of sets in both years which were not oxactly identical as to place or time. Thoso bring the total sots to 17 for 1934 and 15 for 1936. The catches per set were as follows:

Year Char Squawfish Trout Sucker Coho

1934 3.6 2.1 0.5 2.2 0*6 1936 0.5 0.8 0.3 0.3 0.0

This additional information alters the ratios given above for identical sets but slightly and the conclusions concerning the latter arc generally confirmed*

B* Analyses of Length Frequencies. To determine the effect of the fishing effort upon the length frequency groupings of predatory fish captured 9 tho data of samples measured have boon analyzed. For char and trout tho samples obtained for oach mosh from 2" to 4§,w are too «rwyn and the ranges in size too great to provide ready indexes of tho trends of these populations. For some meshes there occur significant decreases in length from 1935 to 1936, in others tho differences arc favourable but not significant while in tho remainder no real differences appear. For squawfish, however, tho data are quite informative and, as shown in the accompanying tabulation, quite significant. The longth frequencies of . samples captured in the month of June in 1935 and 1936 have been analyzed as follows:

June- 1935 June, 1936 Mesh of net Decrease in inches Number of Length Number of Length in Individuals in mm. individuals in eo* length

284 298.6 ^1.1 309 295.7 +/9.81 2*9 173 287*4 ^1.24 504 274.5 +.0.60 12.9 i 237 272.0 + 1.15 293 247.8 ±0*83 24.2 R*E. Foerster and W.E. Ricker No. 20 Significant decreases in mean length occur in all cases and Indicate that^ due to the fishing effort, the population of squawfish is being appreciably reduced. For the other species the data are not as significant but arc nevertheless indicative of a similar trend*

R.E* Foorster and W.E* Ricker No* 21

Tho Estimation of tho Squawfish Population of Cultus Lake by Means of Tagging. luring the month of Juno, 1935, a total of 451 squawfish, captured in Cultus lako by gill nets, were tagged by means of a metal tag on the left oporculum and released. This was done in c.n attempt to use the Petorsen-Dahl method of enumerating the lakeTs total squawfish population whereby the tagged fish would mix with tho general lake population and from subsequent recapture of tagged and untagged individuals a calculation of the total number could bo made. Tho fish seemed much disturbed by the tagging operations as several wore found floating dead on the lake after a fow days, others swam or drifted to tho outlet stream and wore stopped at the screen fence there at a time when practically no untagged squawfish wore so taken, and almost all of the specimens recaptured, even theso taken a year later, had failed to incrcaso in longth after tagging. Tho comparison of place of tagging with place of recovery showed that tho squawfish unvud freely about tho lako, usually along shore in summer. Several had travelled more than a mile overnight. On the first day of tagging, Juno 6th, 41 squawfish were tagged and a total of 9 recaptures were made* One of those- latter was obtained within a fow days of tagging and thus rejected, leaving a recovery of 8 individuals from 40 tagged or 20 per cent rocovc;.ry0 From June 7th to 21st, tho remaining 410 were tagged by different operators and with a different technique and tho recaptures totalled 31, of which 20 wore rejected. The recovery from tho larger and more extended tagging was thus 13. out of 390 or 2.8 per cent. As between these two percentages of recovery it is necessary to assume that the larger is the more representative of the actual efficiency of the nets in the lake and that the seco?)d is tho result of a much higher mortality, greater loss of tags, etc. Such accidents could scarcely have been totally absent from the first group and consequently the 20 por cont recovered is a minimum percentage of the fish which wore removed by gill nets from the lako subsequent to July 1, 1935, The total number of squawfish of medium size netted since July 1, 1935, is approximately 6,800 and on the basis of a 20 por cent fishing effort tho maximum population of tho lake in June, 1955^ may bo calculated as 34,000. This is, however, oven more a maximum population than 2C por cent is a minimum percentage recovery for it makes no allowance for (1) natural mortality among tho fish which were tagged or (2) an influx into the "catchable" group of squawfish which wore in Juno, 1935, toe small to bo caught in the gill nets. Both of thoso factors, of which no nunorical estimate can yet bo mado^ tend to make tho calculated population of 34,000 squawfish too high, R*E* Foerster and W.E. Ricker No. 21

Although the tagging program has not provided any exact information as to the number of squawfish in Cultus lake it has at least shown that the number is not unreasonably great in relation to the number being removed by netting. Efforts to reduce the population by netting, even at the present rate, have encouraging prospects of success. A further tagging program is at present under way to obtain further data relative to tho oxtont of tho present squaw fish population. Tho season of tho year and the condition of the fish should render the results more definite.

R.E* Foorster and W.E. Ricker No. 22

"Residual" Sockeyo Salmon Populations in Cultus Lake»

Studios of tho seaward-migrating sockeye from Cultus lake have shown that tho usual age at migration is one year. Not infrequently an appreciable proportion of a year^-class fails to migrate at tho end of the first year and proceeds to sea the following spring as two-year-old. Very rarely a three- year-old migrant is taken. There exist, however, in Cultus lake populations resulting from the spawning of sea—run sockeyo which novor go to sea and which completo their development in tho lake. Those wo tern "residual" populations. Thoy have the following characteristics: (1) Great variation in numbers in different years. After a very largo yearling migration there occurs a comparatively large residual population but tho converse is not always true. (2) Predominantly male. The largest proportion of females observed was one in sixteen, in 1936. (3) Commonly maturo at three years. Some individuals have been recovered in their fourth year and in 1932 a large number of mature two-yoar males were found* (4) Differ markedly from tho truo kokanec or land-locked sockeye, of which there is a small population in the lake, in their abnormal sex ratio, in size and colour at maturity, in time of spawning and in susceptibility to tho parasite Salmincola. The presence of a residual lake population of sockeye is of serious interest from tho standpoint of conservation. Tho direct effect lies in the fact that each member of this population was, in its first year, a potential seaward migrant; its failure to migrate constitutes a potential loss to the fishery* The indirect effects may, however, bo of greater importance for up to the time of their maturity tho ford of thoso largo sockeye is essentially tho some as tho fingorlings in thoir first year. Consuming relatively larger quantities of plankton, otc», they compote directly with the younger sockeye for food and in somo seasons may seriously handicap the fingorlings in rate of growth and in survival* Two studios dealing with tho Iifo history of young sockeye in Cultus lake are now being completed by the senior author, namely, factors influencing tho seaward migration of sockoye, and the effect of size of population upon the growth rate of young sockeyo. J.L. Hart No. 23

Sexual Dimorphism in Meristic Characters of Capelin

An exploratory investigation of vertebra number in capelin indicated sexual dimorphism in vertebra number. This has either not been thoroughly analysed or has been found not to be the case in other fishes and was accordingly made the object of further study with additional material. Altogether vertebra counts were made on 442 male capelin and 167 females using a binocular microscope and alizarin stain. The grand averages for samples taken over four years were males 65.65 vertebrae, females 65.13 vertobrae. Consideration of the standard errors indicate that the chances are less than 1 in 10,000,000 that the two averages could bo obtained by sampling similar populations. In view of tho extent to which vertebra counts are used in racial studies of fisheries work, it is recommended that the results be recorded in the literature as a suggestion to othor investigators.

J.L. Hart No* 24

The Pilchard Fishery in 1936.

The 1936 pilchard fishing season was notable in several ways. The catch made off the coast of Vancouver island-was very materially smaller than usual, the deficiency being sufficient to lead to operating losses for somo of the operators. On tho other hand, a considerable body of fish penetrated beyond the west end of Vancouver island with the result that a small but successful reduction operation was carried on at Namu. Many small fish wore mixed with the commercial schools; these constituted a major nuisance to the fishermen as thoy gillod in tho nets making then difficult to lift. The biological causes of these phenomena wore investigateu by sampling tho commercial catch for longth and sox during the season. For the first time since tho sampling of tho pilchard catch for longth was begun, the length frequency distribution shows two definite groups of fish^ the appropriate curve having well-marked modes with centres at approximately 193 mm. and 245 mm. for males and 195 mm* and 250 mn. for females and minima at 213 mm* for males and 218 for females. Fish of tho size included in tho smaller group in longth are an entirely new element in the British Columbia pilchard fishery and consequently no forecasts in regard to their future in tho pilchard stock can be made* Evidently it is a different year class or group of year classes but it cannot be stated whether its phenomenal appearance is duo to tho presence in the pilchard stock of this group in unusual abundance, whether its high representation is only relative being due to reduction in tho numbers of larger, older pilchards, or whether in association with tho general northward movement of the pilchard population small southern fish such as those taken in the California summer fishery entered the area fished by Canadian seiners* Inspection of the mode for larger fish indicates Its position as being somewhat lower than during the previous year. This change may be due to differences of technique associated, with a change of investigator, dying out of the oldor and J.L* Hart No* 24 larger fish in the population, or the influx of a new population in addition to that represented by the distinct group of small fish* As analysis is not yet completed, no explanation is offered at present* Continuation of sampling for length during the next two years should contribute to the explanation of both modes in whole or at least in part. The average vertebra numbers of fish in the two groups have been determined separately. They have been found to be 50.75(5) for tho group of small fish and 50.60 for the larger fish. This confirms the suggestion made in annual reports that marked year class variation exists between pilchards in vertebra number. The point is of considerable importance as reliable authors hafre based conclusions in regard to Pacific pilchard populations on average vertebra numbers combined without reference to year of investigation* It would appear that year class variation in vertebra number is greater than the differences between localities north of the United States-Mexico boundary* Indices of availability of pilchards have been prepared from records supplied by the fishing companies and are shown compared with the indices for previous years in tho following tabulation:

1934 1935 1956

Average season's catch per boot (tons) 2120 2170 1520 Average catch per boat por day (tons) 25.3 27c-0 l-3->6

Thoro is no reasonable doubt but that the decline in availability indicated by these figures is significant* It is believed that the decline is not tho result of unfavourable weather conditions and it is accordingly the result of either a sharply reduced abundance of fish or of a change in their summer feeding grounds which in turn is probably related to oceanographic conditionsr Tho latter appears to bo the most plausible explanation. In spite of tho insufficiencies of tho longth-sampling method of studying the pilchard population it has provided valuable information in regard to the entrance into and passage through the fishery of dominating groupso It is recommended accordingly that such sampling be continued, augmented hj vertebra counts as during the past year. The fundamental causes of changes in availa bility of pilchards can never be understood until the oceanography of the north east Pacific is elucidated. It is recommended, therefore, that the oceanography of the area off Vancouver island be investigated, keeping in view that for the purposes of the pilchard work the investigation shall bo designed to give comparative data from year to year.

J.L. Hart No* 25

Application and Recovery of Pilchard Tags.

Two of the unknown factors in regard to the pilchard's life history which are of the greatest interest to problems of exploitation are7 (1) the extent of migration and (2) the relative intensity of the fishery. Both of these J.L. Hart Wo. 25

factors are capable of elucidation by a suitably controlled tagging programme, Consequently, the work on the development of suitable tagging methods begun last year was continued, some 2700 tags were applied, and recovery equipment /^ was installed in six of the seven plants which were operating. Following the indications of last year's work, a rigid pound was constructed for use in the tagging. Trial showed that this pound could not be towed by the "Ron-a-vic" fast enough, to keep up with tho pilchard fleet and consequently give roasonable assurance of over getting fish to tag* Accordingly, a larger boat was chartered for a short poriod and tho pound was carried on dock whilo following the fishermen. This procedure proved to bo moderately successful but tho pound as constructed had a number of oxtorior angles which made tho fishermen unwilling to allow it alongside their not3. Accordingly, the method of the previous year, i.e., tagging from the soine boat's skiff, was usod again. Recovery was accomplished by means of blectro-magnets placed in tho moal lines of the reduction plants between tho driers and tho grinders in such a position that all of tho dried but ungrounh meal passed over them. Tests showed that from 40 to 100 per cent of tho nickel-platod iron tags going into tho plant remained fixed to the magnets and were recovered» Seventeen recoveries havo been made to date., Two of theso were from the 900 tags applied in 1935, tho remaining 15 from tags applied in 1936. They represent approximately ^ of 1 per cent and -§• of 1 per cent of tags applied. However, it is not possible at the present time to deduce from that that the fishery takes between § or J per cent of tho pilchard population each season* The majority of tho returns havo been made within a few days of tho date of application of tho tags which suggests either that tho body of pilchards is moving rapidly or that mortality as a result of tagging is excessively high* It soems possible that parts of tho pilchard population are intensively fichs3 for a few days and then move on to be replaced on the fishing grounds by other schools, snail movements both to eastward and westward are shown by tho rotums of tags within a wook of tagging date. Tho two tags which were applied jn 1935 and were recovered in 1936 wore applied 20-25 miles south-wost of Nootka* One was recovered inside Ououkinish inlot to the westward and the other 9 miles off Gowland rocks to the eastward. Closo contact is being maintained with investigators in California and Cteegon* Both have installed recovery apparatus and tho Californion scientists are tagging also* So far, no tags from ono major area have boon recovered in another. The recovery method has proved to be reasonably satisfactory. It has the disadvantages of not allowing actual examination of tho rocovcred fish as the tag is recovered in tho meal, and that, as tho tag may occasionally be hold up in tho machinery, thoro is some doubt about tho time and place of rocovorye However, remedial measures involve both high initial cost and rather largo operating expenses, so they aro not recommended at the prosent time. Much improvement could be made in tho technique of tagging. A woll constructed rigid pound free from external angles and a boat capable of carrying it on deck aro urgently needed for tho efficient continuation of tho work. J.L. Hart and A.L. Tester No. 26

The Insertion and Recovery of Herring Tags.

Racial studies have demonstrated the existence of essentially discrete runs of herring about the coasts of Vancouver island. In order to supply direct proof of the existence of such local populations and provide informa tion on the intensity with which they are exploited by the fishery a programme of tagging and recovery was introduced on the south-east coast of Vancouver island. In tagging, fish were dipped into a small floating pound from the Commercial purse seines as soon as possible after a set was made. The tags which were three-quarters of an inch long made of nickel-plated iron wore inserted in tho abdominal cavity of tho fish through a small incision in the body wall, T/c tagged fish wore then released to mix with othor schools. The distribution of tags is summarized in tho following tabulation:

Place of release of Date of release No. of fish 1936 tags Remarks

Swanson channel Oct. 6-20 4,790 Tagging on 6 different days. Sooke Oct. 15 "1,500 Fish taken from salmon trap. Porlier pass Nov. 8 300 Fish tagged direct from seine* Porlier pass Nov. 12 1,200 Porlier pass Nov. 18 500 Porlier pass Nov. 19 300

An induction dotoctor for recovering tho magnetic metal tags was installed at a saltory on north Galiano island. This equipment consists essentially of two coils which are kept in balance by radio apparatus and a trap door operated by compressed air and controlled by an electrical relay system. One of the coils, together with the trap door, is installed in an inclined chute between the elevator and horizontal conveyoT system of the saltery* When a tagged fish passes through the coil, an electrical disturbance is created which results in the opening of the trap door and the capture of about 100 fish, one of which contains the tag. These are again passed through tho apparatus in small numbers and the tagged fish is isolated. The machine was operating efficiently during the last three weeks of fishing (Nov. 8 - 28). During this period 43 tags wore recovered from catches made in Trincomali channel near Porlier pass. Two of these were inserted at Sooke on Oct. 15 and the remaining 41 were inserted from Nov. 8 to 19 on the fishing grounds where they wore recaptured. Of great interest is the recovery of the Sooke tags for it shows that some at least of the fish caught in Trincomali channel migrated to that locality through the strait of Juan de Fuca* Tho lack of recovery of tags inserted in the general vicinity of Swanson channel indicates that the tagged fish and the schools which they joined were not present in Trincomali channel while fishing in that locality was in progress. The order in \7hich the recovery of the tags was made suggests that the herring school is not a staple unit. J.L. Hart and A.L. Tester No. 26

Knowing tho number of recoveries at one plant, tho quantity of fish passed through that plant, tho efficiency of tho recovery apparatus and tho total tonnage taken by all plants, it is possible to calculate the probable number of tagged herring captured by tho fishery* Neglecting tho Sooko returns and adjusting tho rosults to take into consideration tags lost while balancing the apparatus and isolating the tagged fish, it is estimated that 55 tags were present in tho 1880 tons of fish which were tested. Although the catch records aro incomplete the total quantity of fish captured by all plants during the three-week period of rocovery is estimated at a minimum of 6000 tons* Therefore, the minimum probable number of tags taken by the fishery may be calculated at i75, or 7.6 per cent of the 2300 tags which were inserted on the Trincomali channel fishing grounds. Considering the returns from the tagging of Nov. 8 only, similar calculations show a probable minimum recovery of 53 tags from 300 inserted, or 17.7 per cent. As these tags were subject to recovery during the whole three weeks, within the limits of sampling the results indicate that at least 17.7 por cont of the fish on tho fishing grounds were captured by the purse seines. This estimate must be regarded as a minimum for the mortality caused by tagging has not been taken into consideration* As tagging proceeds and additional recoveries are made in future years it should be possible to obtain a reasonably accurate estimate of the mortality caused by the fishery for each population* This information will be of prime importance in determining tho optimum quantity of fish to be taken for the most efficient exploitation of the fishery,, The important results which havo been obtained by the use of this equipment over only part of a season justify the recommendation that another similar unit be installed on the west coast in order to permit the investigation of problems related to tho herring fishery there. Field experience leads to the recommendation that better boats and pounds of more refined design be employed in this work in the future.

J.L. Hart and A.L. Tostor No* 27

Condition in Herring.

The chemical composition of herring is important in determining the most advantageous commercial use. This is especially true of oil content* The aim of this investigation has been to establish the relationship between oil content- as determined by standard chemical analyses and condition factor as calculated by the usual formula K »^j. Where Wis the weight, L the length, and x is found by trial for the race and species of fish under examination* The investigation has demonstrated several interesting relationships. Highly significant negative correlations were found between the oil content of samples and the number of days after July 1. A significant positive correlation r « 0.560 (P (0*01) was found between the oil content and the condition factor. Although such a relationship is to be expected, attempts to demonstrate its. existence by at least one other herring investigator have failed to show it. The failure was probably due to faulty technique. The JP^ reciprocal relationship found between oil and water content has been referred J.L, Hart and A.L, Tester No. 27

to in former reports. It is recommended that the investigation be repeated with further refinements in the technique of sampling and preparation of specimens*

J*L* Hart and A.L. Tester No* 28

The Efficiency of Various Types of Tags*

The recovery of herring tags by means of both the induction detector and the electro-magnet depends on their mass and form, those of greatest mass and of a certain form being most readily locovered. This investigation was designed to determine the comparative lethal effects of using tags of varying sizes and shapes. At the same time experiments were carried out to determine the relative efficiency of inserting tags in the abdominal cavity and in the dorsal muscles. Tags varying in weight from 0.23 to 2.27 grams were employed and shapes ranged from slender tags 1 inch long io 3/16-*ihch spheres. Fish tagged by the various methods were placed, in different pens arranged in a Roman square and records of tho mortality made every few days during the course of the experiment. The experiment was not wholly successful on account of the high mortality which existed under the experimental conditions among fish tagged by all methods and even among the controls. However, certain comparative results are available. Tags placed in the dorsal muscles had a slight tendency to be lost more frequently than those inserted in the abdominal cavity. The two heaviest types of tags C5/16-inch sphere, 2.02 grams; 1-inch taper pins, 2.27 grams) produced appreciably higher mortality than other tags used* Below 2 grams there was no regular relationship between mortality and tag weight. These facts will bo taken into consideration in the selection of tags for future use. The Importance of having under observation adequate quantitative controls on all tagging experiments on which estimates of fishing intensity are to be based is obvious. It is recommended that every effort be made to secure such controls during future tagging operations.

|pN C. McC. Ifottloy No. 29

Tho Spawning .Run at Paul Crook An attbmpt was made again this year to obtain a count of tho number of spawning fish entering Paul crook, (toing to tho fact that an unusually-largo amount of wator was stored in Paul lako over tho winter, tho initial water lovol was oxtremely high and tho sudden thr.r/ in tho spring addod a largo amount of wator directly to tho run-off. As a consequence tho lako backod up and flooded tho trap-site. Tho fonco and tho trap woro built up but tho wator rose high onough for tho fish to pass around tho onds of tho fonco. About 900 fish woro counted bofore tho water bocamc too high, scale samplos woro taken and a largo number were weighed, Somo data woro obtained during tho early part of tho run concerning tho effect of environmental factors on migration* Throo gill not sots demonstrated tho effect of tho wind on tho movements of tho fish in tho lake. Last year, when tho wator was so lor: in tho crook, hatchery oporations woro curtailed by tho limited movement of tho fish upstroam and tho failure of tho traps to operate satisfactorily. Nor: traps wore construetod last yoar at the ond of tho season and with tho high wator conditions a record ogg collec tion was mado this yoar. Over 2,000 fish woro handled at the hatchory traps and 1*4 million oggs woro colloctcd. The total spawning run into tho crook was probably about 2500 fish i 500,

C. McC. Mbttloy No. 30

Tho Fishing Drain at Paul Lake

A rocord of tho number of fish caugtit by pooplc using tho boats at Echo Lodgo waskopt again this year by Mr. J. Arthur Scott. Mr. T. Mans en also kindly offered to obtain data on the number of fish caught by people using the cottagers* boats and data for 91 days from Ifey 1 to August 16 were obtained. In arriving at tbe total number of fish caught as reported in former years tho quota taken by tho cottagers was ostimatod by adding on a cortain percentage for oach month. Tho data obtained by Mr* Ivhnson show tint tho cottagers havo takon a greater proportion of fish in tho summer months then was ostimatod and tho data formorly roportod are thoroforo bolow tho truo value. From the data in hand for this yoar 7086 fisn ^Q10 roportod at Echo lodgo and the cottagors woro estimated to havo taken about 2550. This placos tho total catch at approximately 10,000 fish. Tho cottagors* quota is roughly 40 por cent of tho Lodgo-boat quota and, if tho data for former years aro ad justed to this slightly highor value, tho total catch for tho past 5 yoars may be stated as follows:

1932 1933 1934 1935 1936

3,000 6,000 8,000 12,000 10,000

Tho avorago catch por boat por day for the 6 months of tho fishing season was as follous:

Miy Juno July August Sop tombor October 8.3 7*4 5.7 6.2 13.7 13*3 C, JfcG. Mottloy No. 30

Tho weighted avorago catch for tho whole season por boat por day was 8*9. This valuo is somewhat lowor than tir.t roportod for last yoar, but it is probably noaror tho optimum catch for Paul lako. According to tho roports of the anglors tho fish woro in pooror condition in tho fall of 1935 than thoy had boon for somo timo. Hoavy fishing in Lfcy of this yoar, when ovor 2800 fish woro cau^it, sorvod to thin out the stock. Tho fish taken lator in tho yoar woro roportod to bo in much bottor condition and the average sizo was said to bo groator* Tho hoaviost fish caught during tho 1936 soason was 6 pounds. Tho fishing offort as measured by tho numbor of Lodgo boats usod was 794 boat-days. This valuo has remained fairly steady since 1933. It was 838 boat- days in 1935 but tho docroaso for this yoar was mainly duo to stormy, unsottlod weather in tho month of Juno. Tho state of tho woathor is probably ono of tho most important factors in dotormining tho intensity of tho fishing, providod thoro is a satisfactory abundance of fish. From tho data obtainod it would appear that tho total yiold of fish could bo reduced to about 8,000 fish por yoar without lowering tho fishing effort, which moans that tho economic valno of tho fishery would not bo offoetod. At tho same timo such a reduction in numbors would rosult in an incroaso in tho avorago sizo with a concomitant in crease in tho value of tho fish to tho sportsman. It is rocommondod that tho annual planting of fish bo reduced from 200,000 fry to 175,000 fry beginning with noxt yoarfs operations.

C. WbC. Ifottley No. 31

The Loss of Weight at Spawning Time by Rainbow lErout.

It is well-known that the "various species o..: salmon and trout feed only intermittently just prior to spawning and may cease feeding altogether during the spawning activities. The final elaboration of the sexual products and the energy required for tho spawning migration and subsequent spawning activities must therefore draw largeljr upon the stored body materials. Tho significance of this has been overlooked in tho chemical analyses of salmon and tho roportod difforoncos in tho oil-centont of tho so-called races of sockeyo salmon of tho Fraser rivor may moroly reflect tho fact that tho samples woro taken from fish at different stagos in soxual dovelopmont and at a difforont stago in thoir migration rnd not nocossarily indicate an horoditary physical diiforonco botwoon tho runs of tho uppor and lower Frasor. in opportunity for studying tho loss of woight in a singlo population of spawning rainbow trout was afforded at Paul crook in tho spring of 1935. About 1300 of the upstroam migrants woro taggod and woighod and about 600 taken at random woro again woighed as they roturnod to tho lako after spawning. Sinco tho tags usod woro sorially numborod an oxact record of tho loss of weight by oach fish could bo determined. It was found that the avorago woight of tho malo gonads amountod to about 5 por cont of tho total body woight whorcas tho fomalo gonads mado up about 19 por cont of tho total body woi^it. Tho matorial loss duo to the shedding of tho soxual products was estimated at 2 por cont of tho body woight in tho caso of tho malos and about 16 por cont in tho case of tho females* Tho avor ago loss of woight by tho malos amountod to about 16 por cont of tho body woight C. McC. MDttloy No* 31 boforo spawning whoroas tho average total loss of weight by the females was .about 25 per cent. From thoso data it was calculatod that tho unaccountod for loss amountod to about 14 por cent in tho malos and 9 por cont in tho fomalos. Tho unaccountod for quota is probably roprosontod by tho natorial usod up in tho production of onorgy and to a cortain extent that required for tissuo .repair. Thoro is somo ovidonco from studios on othor anirr.ls to show that tho skolotal structuros con tinue to grow at tho oxponso of other tissuos during starvation* This may bo pertly involved in tho hotorogony in many of tho body parts of tho maturo trout as suggostod in a rocont Progress Report. Thoro is ovidonco to show a direct corrolr.tion botwoon tho amount of woight lost and tho longth of tino spent in tho crock, although tho relationship is complicated somewhat by tho fact that at tho ond of tho run, owing to tho riso of tomporaturo abovo tho optimum, there is incomplete spawning. Tho woight of tho unshod oggs would therefore tend to niniriizd iho onorgy loss in tho av orago valuos* Tho small fish, particularly tho small malos, oat oggs at spawn ing timo and tho proportionate loss of wei^it is thoroforo much less in this class* Thoro is considerablo variation in tho loss by difforont individuals* Somo of tho malos lost as much as 30 por cont of thoir woight and somo of tho fomalos ovor 40 por cent* It is obvious that spawning i;i trout places a groat drain on tho body re serves. M>st of the fish tagged in 1931 and recaPfeg|&ain subsequent years made practically no gain in weight. For instance, a.?remale going downstream in May, 1931, weighed 3.2 pounds; it was again weighed when going upstream in 1935, four years later, when it was 3.7 pounds. There is a common belief among the anglers that rainbow trout continue to grow indefinitely after spawning but this is apparently not tho case. Once the trout roach maturity and spawn a considerable amount of food is required to mako up for tho material lost, to renew tho roproductivo products and to supply tho onorgy for tho noxt spawning migration. TJnloss tho food supply is vory rich thoro is only a slight gain in woight from yoar to yoar aftor tho fish bocomo maturo adults. In tho majority of cases tho sizo ultimatoly attained by rainbow trout appoars to dopond on tho rato of growth in tho first fow yor.rs of life boforo maturity is roachod and this in turn is dependent on tho food supply*

0* McC. Mottloy No. 32

Inoroasing tho Nutritivo Capacity of Paul Ir.ko

During tho investigation of tho trout-producing capacity of Paul Ir.ko it has boon found that thoro has boci a groat drain on tho population of Qcmmarus living bolow tho Chara zone. This has had an important offoct on tho growth rato of tho fish sinco tho larger trout retire to tho doopor wator during tho summor'and are practically depondont on this food typo for a part of thoir growth. Tho not rosult of tho intensive stocking program carriod on for tho past six years has boon a doplotion of tho food supply in tho doop wator with a consoquont chock in growth during tho sunmor. The avorago weight of tho fish has boon roducod in that tho ::r.xinun sizo attainod by tho largor fish has drop- pod from 10 pounds in 1932 to about 5 pounds in 1936. It has also boon found that tho shoro-zono, which Dr. Bawscn estimated in 1931 as producing 90 pounds No. 32 C. McC. Ifettloy of organisms per acre; has not been contributing directly to the production of trout. It would seem that the situation mi git be easily remedied by the intro duction of a suitable forage animal. After a good deal of consideration it was thought undesirable to introduce a minnow as a forager* There were two main considerations in arriving at this conclusion: in the first place tho minnow would compete directly with tho young trout for food, principally for organisms such as Cladocora and chiro- nomids, and would not mako tho main shoro fauna, chiofly tho amphipod Hyalolla, available to tho trout; in tho second placo, information has como to hand that minnows, such as tho lako shiner, food on froo-swimming irout fry and this would directly intorforo with tho systom of planting in Paul lako. In spito of tho objections raised against tho introduction of tho lako shiner this may soon bo an accompli shod fact* Tho hoadwators of tho Paul crook drainago aroa lio in closo proximity to tho Louis crook drainago, a tributary of tho North Thompson rivor, which is populated with tho various spocios of fish native to -Bio in tori or of B.C. It is but a few minutos walk from Silont lako on tho Louis crook sido to Bridgo lako on tho Paul crook side* Tho formor con tains a largo population of tho lako shinor, Hichardsonius baltoatus, and on ovor-zoalous fish culturist, homo-stoading in tho district, transforrod those fish across. Tho shinors havo flourished in tho new lake and aro now spreading down tho systom and havo boon roportod in Pinantan lako, two milos abovo Paul lako. It would soorn to bo higily undosirablo to havo thoso fish ontor Paul lake, partly because of tho oxporimontal work going on, but chiofly bocauso of tho value of tho Paul lako sport fishory to tho country. Tho possibility of an influx could probably bo mot by tho construction this spring of a revolving fish scroon on Paul crock; at loast somo action is urgently recommanded. In ordor to increase the nutritive capacity of the shoro-zono tho cray-fish was decided upon as the most dosirablo form. Being bottom foodors and having •a tondoncy to livo in shallow water togothor with tho fact that thoy form an approciablo itom in tho food of trout whoro tho two have boon found in tho samo body of wator tho crayfish soonod tho only typo that would fit tho roquirorients* Consequently 400 Potamobius trowbridgi (leniusculus?) were obtained from Shawni gan lake on Vancouver island" and transferred to Paul lake. The transfer it self was interesting because the attempt was made on July 30, one of the hot test days of summer. The animals were packod in four rectangular boxes, 12 x 18 inches and 10 inches deop, in damp moss with ice on the top* They were about 20 hours in transit and not a single loss was reported. In ordor to increase tho food supply of tho doop water a preliminary study is now being mado of tho possibility of transferring tho deop wator crustacean, Lysis rolicta, of tho Groat lakes to Paul lako. Owing to tho pos- siblo dangor of introducing an undosirablo parasito it may bo nocossary to introduco individuals in an oarly stago of development. Tho culturo of ifesis is now boing attomptod on an oxporimontal scalo at tho Univorsity of Toronto by Jfr* C.C. Carl. It has boon noticed in aquarium culturos that Gammarus limnaeus has a tondoncy to swim off tho bottom to a greater oxtont than othor spocios and it sooms possiblo that it cannot withstand the attacks of tho trout without tho prosonco of sholtoring plants. This is probably tho roason why tho spocios flourishes when associatod with Chora, a plant that persists all tho yoar round; in unsholtorod areas, such as tho doop wator zono, it may thus bo soon exterminated by tho trout. Othor spocios of amphipods, such as tho doop C. MsC. Mottloy No. 32 wator form, Pontoporoir., might bo introduced to advantago in Paul lako. Pon- tonoroia can bo obtainod in lako Viashingtca near Seattle and specimens for preliminary studies could bo easily obtainod. It is rocommondod that this bo undortakon noxt year.

C. McC. Mbttloy No. 33

The Introduction of the Byown Trout on Vancouver Island The final plantings of brown trout as originally planned in 1931 were ©ompleted this year by the distribution of 48,000 yearlings in the Little Qualicum river. This brings the preliminary stages of the experiment to a close. The introduction into the Little Qualicum has been made by the fol lowing plantings: 1932, 8,500; 1933-34, 74,868; 1934-35, 114,696; 1935-36, 48,793. The majority of the fish were reared to tho yearling stage before being planted but in 1934 a number were also planted as fingorlings* The comploto figures for the plantings in tho Cowichan rivor havo boon roportod in tho annual report of tho Dopartmcnt of Fisheries. Tho numbor planted in tho various years is as follows: 1932, 126,000 advancod fry; 1932-33, 30,589 yearlings; 1933-34, 22,880 yearlings; 1934-35, 28,720 yoarlings. In tho first two yoars of tho introduction many of tho fish liboratod woro marked by tho removal of tho adipose fin in ordor to facilitate tho rocognition of tho fish by the anglers* Ivhny of those fish have boon caught and a numbor reported, although no attempt has boon mado to obtain full in formation by tho payment of rewards. To date tho introduction has boon more successful on tho Cowichan river but tho Littlo Qualicum operations woro a yoar bohind because'tho first planting was oxtromoly small* Tho brown trout havo boon roportod from Cowichan lako rnd several specimens woro caught this yoar noar its head. Ono fish was roportod as woighing four pounds. last yoar a few fortilo brown trout eggs woro recovered from natural spawning in Oliver crook noar tho hatchory. The oggs woro hatchod in tho hatchory© Spawn ing takos place in lato Octobor and November at tho usual soason for this spocios. Sovoral specimens woighing up to a pound and a half havo boon caught noar tido-wator on tho Littlo Qualicum. Mr. Higgs, in charge of tho Qualicum ponds, mado a spocial investigation of tho succoss of tho introduction in somo of tho tributarios in which tho fish had boon plantod. Ho roports taking sovoral brown trout by fishing but tho fish aro small not reaching a sizo grcator than 9 inches. Thoy aro associated with tho nativo cutthroats in tho streams and avorago about tho samo sizo. A fow markod trout woro capturod at tho samo timo. Apparently the brown trout tends to stay in tho locality in which it is plantod, although tlio information obtainod on tho Cowichan shows that thoy may movo upstroam on roaching maturity,, A fow roports havo boon mado of tho food of tho brown trout and in most cases it has consistod of small fish, chiofly sticklebacks and tho fry of salmonoids. Thoy aro probably no more piscivorous than tho nativo cutthroat but thoir tondoncy to remain in tho tributarios givos thorn groator access to tho salmonoid fry. It will bo difficult to ostimato just what offoct tho introduction will liavd on tho runs of salmon and nativo trout* With regard to tho desirability of the brown trout as a gamo fish tho majority of tho anglors roport that it is slightly inforior to tho nativo cutthroat. It has providod somo angling in tho Cowichan rivor during tho "off" summer season but tho fish aro not abundant enough yot to mako this an impor- C. IfcC. Mottley No. 33

tant attraction. Ihe real test will come when the second generation of trout produced under local natural conditions becomes available* jp^. C. McC. MDttley No. 34

Contributions to Fish Cultural Practice During the period of supervision of the introduction of the brawn trout into the Little Qualicum river it has been the policy of the writer to make some experiment oach year that would contributo to the gonoral practico of fish culturo without interfering unnecessarily with tho routine work. In 1933-34 an oxporimont in keeping accurato records of losses was undertaken. In 1934-35 experiments in grading, sampling and night feeding wore carried out. In 1935-36 further studies of grading and sampling methods woro mado. It was found that a singlo grading in tho late summor could bo made with effoctivo results. Tho brown trout woro carriod in 3 ponds until August 10, 1935, whon grading was started, and 8,000 of tho small fish woro takon out end placod in a soparato pond. When tho fish woro counted out in March, 1936, tho numbers prosont tallied within a fow fish of those supposod to bo thoro and it was concludod that no cannibalism had occurred. Tunison and McCay recommend that, in ordor to obtain satisfactory rosults, fish in ponds should bo fod an amount of food oqual to a cortain porcontago of thoir body woight oach day* For small fish thoy rocommond tji amount oqual to 10 por cont of tho body woight por day raid tho porcontago is progressively loworod as tho fish incroaso in size. In ordor to carry this out accurately it is nocossary to know how many fish a pond contains and what tho total woight is and in ordor to arrivo at on ostimato of tho total woight it is nocossary to obtain an adoquato sample of tho fish from oach pond. It is obviously imprac- ticablo to woigh all of the fish in production units and sampling is therefore tho only altomativo. Asido from tho difficulty of obtaining a truly unbiassod or random sample, tho main problom is to determine how big a sample should be taken in order to provide a sufficiently accurate idea of the total amount of fish in the pond. A good opportunity for studying this question was afforded when the brown trout were being hand-counted out in Ifach. A total of 48,878 fish averaging about 3 inches in length was dipped out of the ponds in samples weighing approximately 3 pounds on tho average and counted. This afforded 214 samples for tho study of sampling errors in calculating tho woight of the fish* It was concluded that a great deal of care must bo exercised, in taking these samples in order to calculato tho total woight of fish that a pond con tains* A sample amounting to about ono-sovonth of the total numbor of fish in tho pond would soem to bo adoquato to provido an ostimto of tho total woight of the fish so that tho amount of food to bo fod can bo calculated within 10 por cent of the propor amount. Aa experienced fish culturist, howovor, could probably bo ablo to dotcrmine tho amount of food roquirod within limits al most as fino as this by noting carofully how much tho fish will oat without leaving any wasto. C. McC. Mottlcy No* 35

Assistance to tho Provincial Gamo Department in Fish Culturo

Sinco tho Provincial Game Department began its fish cultural operations in 1932 scientific advico has been gLvon on various mattors portaining to its work. In July of this yoar tho officor-in-chargo was forced to rotirofcn account of ill-hoalth and, in tho absonco of a trainod man, tho writer undortook tho super vision of tho activitios in an advisory capacity and was appointod consultant in fish culturo. This arrangomont was to bo a temporary ono with a two-fold purposo: first to placo tho fish cultural program on a more sciontific basis by incorporating into practico a numbor of tho rocont dovolopmonts in this fiold and second to train a subordinato to tako ovor tho dotails of suporvision by tho end of tho fiscal yoar. At the tiiio of tho appointment in July tho Department had on hand a large number of stoolhoad and Khmloops trout in 3 main establishments, Stanley Park, Veitch crook rnd Qjualicun Boach. It now has in thoso throo units 100,000 stool hoad fingerlings, averaging about 4 inchos in longth, and 233,000 Khmloops trout averaging about 2 1/2 inchos in longth. In addition 3,350 steolhoads, 5 inches long, and 165,000 Kamloops trout fry have alroady boon liberated* The hold-ovor of 333,000 fish roproscnts a 40 por cent increase ovor last yoarfs oporations. In addition to tho above sovoral thousand advancod Kamloops trout fry havo boon liberated by tho Rovolstoko Rod and Gun Club from tho Biological Board*s ponds at Tp.ft by moans of oporations subsidized by tho Gamo Dopartnont. Sovoral thousand Khmloops trout aro also boiiig roarod in natural ponds at Kblowna and Princoton by moans of Gamo Department grants. Finally tho operation of tho Cranbrook hatchery was portljr subsidizod by a grant. In exchange for tho stoolhoad eggs received from tho Cowichan hatchery tho Gamo Dopartmont also undortook the roaring of 23,000 spring salmon for a mark ing program at Campbell rivor. This work will be doalt with moro fully in an other report. Considerable difficulty was experienced this year with the water supplies at the main establishments and the losses were slightly higher than the writer considers to be normal, namely 20 to 30 per cent. The losses in the Kamloops trout to date amount to about 35 per cent; those for the steelheads are slightly less* At Qualicum a swamp at the head of the creek that supplies the hatchery was drained and the increased acidity was possibly responsible for the losses. At Veitch creek there was an acute water shortage in July and the fry were crowded in the troughs; tho situation was relieved somewhat by planting the Kam - loops as soon as they could bo moved. At Stanley Park tho usual arrangement of supply was upset by the dry season and tho demand for wator by tho city of Vancouvor. A new supply lino was cut in from tho Capilano watershed but it was too late to aid at tho most critical poriod. ALthough tho supply of water avail able was sufficient for tho hatchery it could not bo furnished steadily to tho reservoir which roachod a vory low lovol and as tho surface water was drawn in the tomporaturo rose to 68°F. Tho high tomporaturos occurrod just at tho timo the Kamloops fry woro beginning to food and woro considerably abovo tho optimum* The rosorvoir could only bo filled during slack periods with the rosult that every once in a while tho tomporaturo would suddonly drop to that of tho city mains, about 6003T* During-tho poriod of fluctuating tomporaturos high losses occurrod. Tho sudden drop in tomporaturo at tho timo of tho filling of tho re servoir resulted in incroasod lossos among tho stoolhoads. Satisfactory arrange ments with rogord to tho water supplies both at Veitch crook and Stanley Park "J> '\JvV-. Vl C. EbC. fettley 'V^VV J^Vjj'4 N°# ^ were made by the middle of August and the losses have bafen nearer normal expec tations since that time. The writer has pointed out on a number of occasions that the eggs destined for pond cultural operations should bo of prima quality but in spite of this Jp\ for a numbor of yoars noorauality Kamloops trout oggs^vobomsjgggjjpd for tho Gamo Departments plants. iMsyoar was no oxcoption. Tho majority of tho oggs came from Eonask_lakcu^as in past yoars, and in addition tho Gamo Department undertook to salvage tho'eggs from a collection of fish that woro loft ovor aftor tho stripping operations at Beaver lake. Tho ond of tho spawning run of trout is ofton characterized by out-of-condition, poorly mondod kolts and, moreover, Ithoso fish had boon hold for sovoral days; as a consoquonco a vory poor batch |of oggs was obtainod. It should be romoriborcd, howovoiS that undor tho partic ular circumstances tho operations woro somewhat in tho nature of salvage end, although tho subsoquont lossos may havo boon fairly heavy, tho survival may bo considered as a clear gain. in important phase of tho consulting work has boon tho changing of tho feed ing tochniquo and tho diet of tho fish. With a via:; to obtaining a moro balanced diet and lowor costs sovoral experiments aro now in progress at Stanley Park* Somo of tho findings havo alroady boon incorporated into standard practice* The diot of powdorod skim nil?: and frosh boof liver, in oqual proportions, as usod in imorican hatcheries for tho fry was adopted. Tho standard diot now in uso for older fish at Stanley Park is as follows: frosh boof livor, 15 por cont; powdorod skim milk, 35 por cont; frozon fish roo and livors from 12io Eraser rivor commorcial salmon fishery, 50 por cent. A mineral mixture, consisting of oqual parts of common salt, bono noal and procipitatod chalk rsid 2*5 grans of potassium iodido por kilogram of tho mixturo, is addod to tho ration in tho proportion of 3 por cont of its total woight. This diot costs about 7 cents por pound and its uso has meant a considerable reduction in tho food costs. At Stanley Park tho food costs have boon reduced 30 to 40 por cont from thoso of previous yoars. At tho othor plants tho ration has consistod of oqual parts of beef livor rnd powdorod skin milk which has also roducod tho costs. The oxporinonts now undor way aro intended to dotormino tho officioncy of boof livor substitutes and it is oxpoctcd that a considorablo sav ing will bo cffoetod along that lino. Owing to tho lack of cold storage facil ities at Voitch drook raid Qualicun Boach tho frozon roo and livors aro not suit able. It may bo possible, how ovor, to got the fish cannorios to undortako tho canning of this product in gallon tins at a low cost. If tho canned product is satisfactory it would mrko an important uso for matorial that has hitherto been wasted. In feeding the ration when the fish are small it is necessary to scatter the food in small particles that slowly sink to the bottom. A certain amount of wastage is unavoidable in the early stages but the fish soon learn to pick up the pieces. The main difficulty with the small fish is to get the particles fine enough. It was found that the ground up or pulped eggs produced a thin, watery fluid rich in the yolk material which, if scattered in the trough on the tips' of tho fingers, provided a source of food readily taken by small or weak fish. The fish roe is in genoral not a satisfactory food for tho young fish because of the largo amount of ogg-sholls that como through tho grindor wholo. Thoso aro prono to plug the scroons in tho trough and cause a good doal of troublo. As tho fish got larger tho food may bo placed in lumps on the bottom 6r on trays suspended in tho wator. Tho powdorod milk acts as a bindor holding tho matorial 0. IfcC. Mbttloy , No. 35 togothor but at tho samox timo softening tho surface as it dissolves and allowing tho fish to bito off piocos of it. It also scorns to impart a flavour to iho matorial which was formerly lacking in boof liver aftor it bocamo wator-soakod. TbD ingredients must bo thoroughly mixed in ordor to obtain tho best results. It was found advisablo to grind the livor and fish roo soparatoly then incorporate tho powdered milk and stir than together rnd finally pass the crudo mixturo through tho grindor again for final mixing. This gives a fairly smooth pasto of tho proper consistency. In tho caso of tho boof-livor-powdorcd-milk ration a certain amount of wator has to bo included in ordor to got tho proper combin ation; tho fish roo when addod, howovor, supplies enough moisturo rnd would otherwise bo wasted without tho binding properties of the milk. Tho diots no., in uso soom to havo incroasod tho rato of growth with a groator efficiency of conversion* Full dotr.ils will be available at a later dato. In ordor to incroaso tho efficiency of tho ponds at Stanloy Park tho stool- hoads woro graded in Septomb or and all tho fish over 3 inches wore placod in separate ponds* Somo of those now moasuro 6 inches. Standard grading methods will probabljr be incorporated in next year's program. Instead of thinning the fish out into spare ponds, which must necessarily remain idle until required, it will be possible to start with a greater number of fish, thin out the ponds by grading out the large fish in September and planting them. Experiments in grading the Kamloops at a much smaller size aro also undor way at Qualicum Beach ponds. Continuing in its policy of assisting in the survey of lakes before stocking, the Game Department made possible a study of Prospoct and Taotis lakes noar Victoria* Mr. G.C. Carl has submitted reports on thoso lakes. A roport on a survey of Jonos lako by the writer was publishod in tho roport of tho Gamo Com mission for 1935* Tho Game Department also fostorcd the improvement of tho Goldstrearn by tho building of low dams to provido pools for coho salmon fingor lings at tho critical stage of low wator in August. Tho Victoria Fish and Game Association and tho Scnnich Inlot Anglors turned out and gavo voluntary labour for this project. Tho Dominion Department of Fishcrios has plantod coho oggs in tho Goldstroam for a number of years but it soons evident to tho writer that tho limiting factor to tho production of cohos in this stream is not a lack of oggs but tho docroaso in tho range of wator during tho critical summer period* This was pointod out last yoar in connection with tho survoy of tho Serpentine and Nicomokl rivers. Ov/ing to tho great valuo of the coho as a sporting fish and to its importance in tho bluo-back fishery it would soon to bo a dosirablo thing to adopt a comprehensive program looking toward management of tho produc tion of this particular spocios. Tho Gamo Deportment has medo it possible for tho writer to comply with the numorous requests by Fish and Grxio organizations for locturcs on conservation - 16 such addresses havo boon given sinco August 1st. C. McC. Mbttloy / ^/^ No* 36 Tho, Planting of Marked Spring Salmon in Campboll Rivor /

For a numbor of yoars tho Dcpartnont of Fisheries has transferred spring salmon from tho Cowichan aroa to Campboll rivor. I-. ord^r to obtain somo idoa of the officacy of such transfors it was decidod to pla^it morkod fingorlings this yoar* Tho ponds at Qualicun Boach boing availably during tho oarly summor tho Provincial Gamo Dopartnont undortook the roaring pf thoso fish. Accordingly, 27,000 fry woro placod in tho ponds on JUay 30 fron which 23,000 fingorlings averaging 3 l/2 inchos in longth woro produced by t:ib first wook in August. Tho fish woro marked by tho romoval of tho adiposo aid loft vontrol fins* Aftor tho narking operations Mr. Higgs, who was in charge, drew to tho writer's atten tion tho fact thoro was a considorablo numbor of deformities with rospect to tho vontrol fins. Sinco ho did not roalizo that information on tho froquoncy of occurronco of such abnormalities was of basic importance in tho interpretation of roturns from marking oporations ho did not keop a. tally of tho numbor of thorn. This observation is extremely interesting in view of tho fact that tho sovoral investigators using tho rxrking tochniquo hovp novor statod tho incidonco of ab normalities in tho fish handlod. / Tho spring salmon fingerlings wore transferred to Campboll rivor on August 6 end 7 by morns of tho Grxio Dopartnoirt's tank truck* On arrival with tho second load on August 7 tho local residents rcpor/uod that thoro had boon a heavy loss in tho previous day's planting several ho/rs after tho fish had boon placod in tho wator. Tho writer stayed on tho ground therefore on August 7 and obsorvod tho roaction of tho fish. Both plantings wore r.do in tho forenoon abovo tido-wator near tho highway bridge* Tho planting was carried out in tho usual way by noons of a hoso from tho tank truck. Most of tho fish passed dam tho rivor congrogating in pools for a hundred yards or more bolow tho planting sito. A considorablo nunbor, howovor, remained in tho fast wator fighting tho current. In about an hour aftor tho planting thoso fish began to go into violont novonaits swimming in all diroction and ovon junping out on tho bank. Somo woro hold in tho hand in quiet pools and they gradually rocovorod and, for tho timo during which they woro obsorvod, appoared to bo normal, though list loss. It was cstimatod by going over tho wholo ground by beat lato in tho aftornoon tlr.t tho loss after planting amountod to about 25 por cent of tho fish* It seemed that only those fish that remained in the fast current were affected. There are very few studies on the respiration of salmonoid fishes but the writer is inclined to believe that the cause of the loss was due to the dis turbance of the respiratory balance as a result of the transfer* Tho points contributing to this conclusion aro biiefly: For several days prior to the planting, swamp water of high acidity was drained into the creek where the Qnalicum. ponds aro situated; this would condition tho fish to acid wator and draw on their alkaline reserve. The temperature of tho wator at tho roaring ponds was fairly low, 54°F., whoroas tho tomporaturo of Campboll rivor was high, 66°F* in tho morning at tho tine of plcnting but roso to 70°F. in tho afternoon. It took two hours to mako tho joumoy fron Qualicun to Campboll rivor and tho temperature was allowed to riso so that tho tank tomporaturo and tho rivor tomporaturo would bo noro noarly oqual. Tho difforonco was about 2°F. at tho timo of planting. This riso in tomporaturo from 54 at tho ponds to 66 in tho rivor would increase the metabolic rato and tho production of C. HcO. Ivbttloy No. 36 COi. Tho riso in rivor tomporaturo during tho day and tho tondoncy for tho fish to fight tho current would also havo a tondoncy to incrcaso tho production of 002* Tho not rosult would bo that the fish woro producing carbon dioxido at a fastor rato than it could be eliminr.tod. This conclusion is based on the study of tho fragmentary data availablo on tho subject. It is a fiold whoro inves tigation -is urgontly noodod in viow of tho large number of transfors of fish that aro being ix.de from one typo of wator to another. J*A. Itaito and W*A. Clemens No* 37

Investigation of the .American Merganser

Over the period of the past five years a study has been carried out of the life history, particularly the feeding habits and food, of the .American Msrganser, Mergus merganser americanus, and the relation of this duck to the fisheries of British Columbia. It has involved field observations and the detailed analyses of food in the digestive tracts of 363 mergansers and 700 fishes. Yi/hile tho problem of tho relation of tho .American Merganser to tho fisheries of British Columbia is a rather complex ono, tho authors feol that it has boon carriod to a point whoro cortain statements may be mado. It is concluded on x " mHiT fiTf"'"1- Y^riTi 'I '•,i_1TTirrJ~" tho basis of this investigation that tho .American Morgansor in British Columbia '&OG&>ME&t''WfrQtsoly affect tho production of trout and ""salmon "to an appr6'ciaBIb" ''dogreo'because its numbers aro not excessive and its food consists to a vory largo dogroo of ccarso and predatory fishes* That tho authors aro opposod to moasures of control is not to bo assumed from tho forogoing; on tho contrary %^Mvi&j^tmn^,^D^TiJ that circumstances may at timos ariso which warrant a reduc tion in the numbers of thoso birds in cortain localitios* Tho conditions in dicating tho ncod for action would bo tho presonco of unusual numbers during ' tho poriod of March to September on trout or salmon streams togothor with ovi- donce that tho birds woro feeding extensively on Salmonidae* Roports of such occurroncos should bo tho subjoct of a biological investigation with action on tho basis of tho rosults. T/ilhen spocial measures of control aro necessars^, thoy should bo regarded as a corroctivo for a temporary abnormal condition and not as a pormanont policy. In such special habitats as roaring ponds or whoro fish cultural activities aro \ eoncontratod, thoro always will bo a need for continued control* A gonoral re duction of .American Morgansors on tho assumption that at somo timo or in somo place thoy may cr.usc lossos.of trout or salmon is considerod an unsound and un warranted proceduro. A.L. Pritchard No« 38

Report on the Third Investigation to Tost the Sfficienc;/; of Artificial Propa- •gation in Establishing a 3ur. in the "Off" Year in ivloCliaton Creek, ivfesset Ij\let» B.C.

Iii the investigators* summary reports for the year 1935 a brief outline was presented of the beginning of the third experiment designed to check the effic iency of artificial propagation in building a run in LijClinton crock, I&.ssot inlot, in tho ovon-numborod yoars when no pink salmon appoar. From 3-ptombor 2 to Soptomber 10, 1935, oggs woro taken from female pink salmon in tho Tloll rivor on the oast coast of Graham island, fcrtilizod and wator-hardonod. Thoj^ woro im mediately transferred by car a distance of fourtoon miles to Port Clements and thonco by boat a distance of seventeen railos to tho oyoing station on IvbClinton crook* Immediately upon arrival e.ccurato measurement was made by moans of an ordinary druggist's graduate. 3ach day a count was carried out of a moasurod amount and from tho numbor per ounco calculated therefrom and the numbor of ouncos the total in tho shipment.was roachod. To sum of tho numbers in all tho shipments was taken as tho total in tho hatchory, First removal of dead oggs was completed within twenty-four hours oftor arrival. Thereafter no further picking was attempted until tho oyos of tho lar vao were definitely showing (t.rc first wook in October). Sron that timo forward dead oggs and fry wore removed as they appeared. Tho first jfry hatched on Novombor 1 and all wore hatched on December 7. During January, February, March, and April aftor tho fry woro froo-swimming some wore takon from tho troughs and planted in tho main crock to roliovo tho con gestion in tho hatchorjr. Finally approximately one hundred thousand woro held end fod in ordor to procure increased siso which would facilitato tho marking oxporimont. All woro roloascd by 1'r.y 9, 1936. The following is a brief summary of the experiment:

Number of eggs received at hatchery 757,837 Fry planted - unmarked 397,674 - marked 108,200 505,874 Fry - taken for samples 145 loss in eggs and fry all stages (33$) 251,818

757,837 7577837

The loss of thirty-three per cent recorded above appears large. It should perhaps be pointed out that the numbers taken out at first picking eighteen hours after arrival amounted to 115,281. In addition 22,266 wore used for es timating tho numbor por ounco. Tho loss was also heavy from the oyod-egg stage to hatching. This might bo attributed in part to poor fertilization resulting from such things as tho presence of groon or wook oggs, but in tho main it appears to bo duo to tho shaking and handling incidont to tho rough road journey from Tloll to Port Clomonts. Tho fry, numboring approximately fivo hundred thousand, should appoar in tho fishery as adult pink salmon in tho autumn of 1937. At that timo it will bo highly desirable if definite information is to bo obtained, to chock through out tho fishing areas for tho occurronco of markod fish, tho survivors of tho ono hundrod and eight thousand from which tho adipose end right vontrol fins woro removed. It is spocially urged that tho fonco on tho Tlcll rivor bo again put in ple.co and operated to chock tho run to that area. If at the samo timo the run at McClinton crock is examined, tho prosonco of returns either in the "parent" A.L* Pritchard No« 38

or "adoptod" stroam will be ascortainod.

A.L. Pritchard No. 39

The Natural Run of Pink Salmon (Oncorhynchus gorbuscha) in tfcClinton Crook, Massot Inlet, During 1936 ♦

Tho following report contains a brief summoiy of tho data collected dur ing tho current yoar on tho natural run of spawning pink salmon adults arriving at McClinton crook, i&ssot inlot. A table is included in which the counts for tho natural propagation experiment extending from 1930 to 1936 aro roviowod. Tho run in tho autumn of 1936 was somewhat similar to thoso of 1930, 1932 and 1934 but tho fluctuations in numbers migrating daily difforod to somo ex tent largely due to variations in tho time and amount of rainfall with which tho numbers of migrants reaching the fonco again appeared to bo correlated. Once again it was observed that when tho wator was very high, tho pinks could not stem the current but were forced to tho back-oddics whore thoy waited until tho rivor dropped to a moro favourable level. Tho first pink salmon arrived on July 29 and a fow appoarod thoroaftor until August 11. Between August 11 and August 15 thoro was a definite increase duo to incroaso in rainfall. Srom tho latter date until August 26 tho nimibors woro again small* Tho main run occurrod between August 26 ejid October 5* Random samplos neasurod throughout tho run do not give any definite in dication of a progressive incroaso in sizo as tho migration continues* Thoy domonstrato once again, ho7*ovor, as in tho othor yoars tha.t tho malos wore sig nificantly larger on tho avorago than tho females. Tho numbor of oggs por fo- malo as dotorminod from actual counts made on 91 individuals, was 1899 4 12, a total significantly groator than that of any othor yoar. At prosont it doos not appoar that this incroaso can bo ontiroljr duo to incroaso in sizo of tho females but no definite conclusions can bo drawn until tho final correlations aro closely examined. In general tho malos predominated at tho first of the run. On tho occasion of one or two of tho largor froshots tho females suporcodod thorn slightly but after Soptombor 19 tho fcmolos woro in pornanont dordnanco in numbers until the end of the run on October 5* The final disposition of the sexes on the spawning grounds was 46*3 per cent males and 53*7 per cent females. No. .39 A.L. Pritchard The following is a summary of the counts in the propagation experiment to date:

19 3 0 1932 1934 1936 No. of males ™, 955 8,003 77,467 24,221 No. of females 3SJSL. hS3L 22i*£ |MfL Total numbor 66,151 15,600 155,183 52,311 Av. no. ctfegp per ^ ^^ ^ ^^ ^ ^^ ^ , 12 Presumed eg ^ 50,950,000 1^,360,000 139,000,000 53,345,000 No. fry migrants 5,384,000 2,250,000 12,608,000 per cent hatch 10.6 16,7 9.1 s During the year 1936 tho boundaries off tho mouth of LfcClinton creek woro moved in to allow tho fishermen to take a larger porcontago of tho fish. To obtain a figure comparable to that for othor yoars, it is nocossary to add tho commercial catch aftor tho tine when tho move was nado to tho figure abovo. Although all tho certified figures aro not yot to hand, tho catch amounts to approximately 110,000 raising tho return to approximately 160,000. • It is intcrosting to note that in tho event of a largo run with a largo egg deposition tho porcontago return in fry and adults on tho basis of tho ogg deposition is relatively lower. Thus oftor tho run of 1930 the return in fry migrants was 10.6$ and in adults .03$. After the larger run of 1934, those percentages were 9*1 and .12 respectively. On the other hand as a result of the small run of 1932 there occurred in fry migrants 16.7$ and in spawning adults 1.16$. It is indicated that the low efficiency which results on the spawning beds after a large egg deposition is carried through the life cycle to a greater or less extent. It would appear that there is an optimum number which could be found for tho creek at which the efficiency in incubation and the lator parts of tho life history would bo relatively highest.

A.L. Pritchard No# 40

The Recovery of Marked Pink Salmon in 1936. During tho course of tho fry migration from McClinton creek in tho spring of 1935, 85,634 young pink salmon woro marked by tho romoval of tho adiposo and both vontral fins, roloc.sod and allowed to go to sea with the unmarked por tion of tho run which amountod to 12,500,000. According to the indications givon by previous marking oxperimonts thoso fish should mature in the autumn of their socond yoar and thus appoar in tho fishery during tho summer and autumn of 1936. For that reason during tho season just passod tho canneries in nor thern British Columbia woro circularized with posters acquainting them with tho rfact that the roturns wero oxpoctod and offering a roward of twenty-five cents for information as to tho location of capturo of tho markod individuals. A.L*. -r ^PritchardJJ. X. J NO* 40 m all 42 fish lacking various fins were taken at IfoCliuton creek. Of these 29 did not have either adipose or ventrals and were thus ^^ttT the result of the marking in 1935. Six still possessed almost all the adipose but no ventrals. These have been included as part of the return from the 1935 marking since it is likely that the part of the adipose remaining was the result of a faulty marking manipulation which is exceedingly difficult when carried out on fry one and one-half inches in length. Of the remaining seven, five lacked the adipose fin only and two the right ventral. These must be attributed to natural deformity since it is found in some cases that one fin may be missing in nature. Tho total return to IfcClinton from the marking was thus- 35 or .04 per cent. One fish only was picked up at a cannery but it was found on examination that the two ventral fins which wero missing had never been present sinco tho pelvic bonos woro not dovolopod. It is interesting to compare tho ratio of roturn for markod fish with that for unmarkod for tho sovoral years at McGlinton crook*

MARKED UNMARKED

Cyclo No.- 5ry No. Return- Por cont No. Fry No. Return- Por cent migrants ing Adults Migrants ing Adults

1931-32 185,000 95 .05 5,200,000 15,600 .30 1933-34 108,000 2,950 2.70 2,120,000 152,233 7.2 1935-36 85,634 35 .04 12,520,000 160,000 1.3

In ovory cyclo the proportionate roturn of marked fish to McClinton croek is smaller than that of unmarkod. T?-is discrepancy may bo due to either a heavier mortality in tho markod fry or an influx of links from other streams coupled with a wandoring of I&Clinton individuals. At tho prosont time without a dotailod analysis of all tho data it would bo unwiso to state which condition would seem most probable. It is disappointing that only ono roturn was received from tho cennorios, but this condition moroly stresses the fact that if returns aro to bo obtainod in any numbers, it will bo nocossary to establish collectors in cortain cannorios to make examination of all tho fish. Such a programme would bo much moro costly but moro productivo of information. It is unreasonable to oxpoct tho operators to examine all the fish thoroughly throughout the rush of the canning season.

A.I*. Pritchard No. 41

Bfeasurement of the E^gs of the Pink Salmon (Oncorhynchus gorbuscha) Taken from the Tlell River, ^ueen Chariotte Islands, British Columbia.

As stated in a summary report for 1933 it is the usual practice in ordin ary hatchery procedure when the determination of the number of eggs in a ship ment, in a hatchery, etc., is desired, to make several counts of the number contained in a quart measure and from the average thus obtained and the number of measures to calculate the final figure. Various errors may be encountered A.L. Px-it chard No. 41 in this method, e.g.- tho difficulty of kooping tho amount of wator in oach quart tho same, tho troublo oxporioncod in lovolling tho oggs to a given mark, tho impossibility of having tho samo obsorvor mako all tho roadings, otc.-. Nevertheless in somo ca.sos whore it was considorod that such mistakes had boon jJP\ moro or loss successfully eliminated, it was discovorod that whon tho avorago number of oggs por quart calculated whon the oggs woro taken, was usod to com- puto tho number in a shipmont, at tho oyod-ogg stago, tho rosult was highor than the actual count. This indicatod an increase in sizo of tho oggs during incubation. In an effort to got moro accurato information on this subjoct moasuromonts of tho dinmotors of Tloll rivor Pink salmon oggs woro mr.do oach wook at I&Clinton crook hatchory in a specially constructed brass trough scribod carefully in centimetres and inchos. Tho samo obsorvor mado tho observations in 1933 and 1935 undor conditions as nearly similar as possiblo. Tho following is a summary of tho avoragos obtainod from tho moasuromont of twonty sots of ton oggs from a givon lot oach wook from tho timo whon thoy wore takon into tho hatchory until just boforo thoy hatched:

19 3 3 1 9 3 5 Dato Avorago Dato Avorago Sept. .685 4 .0018 Sept. 13 .724 4 .0017 » 12 .683 4 .0015 ?» 20 .725 ? .0017 " 19 .680 4 .0009 »i 28 .713 4 .0018 " 26 .678 J ,0024 Oct. 4 .703 i .0025 Oct. 3 .676 4 .0012 it 11 .696 4 .0014 " 10 .682 4 .0017 ii 18 .702 4 .0018 " 17 .685 4 .0018 !S 25 .698 4 .0018 Nov. 1 .697 J .0018 ii 8 .699 £ .0016 »i 15 .700 4 .0020

Refined statistical treatment of tho data lis tod abovo has shown that in both years tho difforonco between tho groatost and loast avorago is significant. In other words, tho sizo of the oggs as indicatod by thoir diamotors decreased in 1933 until tho wook of October 3 and in 1935 until tho week of October 11. In 1933 thoro is also a significant incroaso from tho wook of October 3 until tho final measurement on October 17. In 1935 this difforoncc botwoon tho loast avorago and tho final ono is indicatod but the difforonco is just outsido tho limit of statistical significance. In both yoars the dato at which minimum dioxiotor sizo occurrod corresponded with the timo whon tho oyos of tho ombryos could first bo cloarly soon in the oggs. Wo may thus stato that thoro was a dofinito docroaso from fertilization to eyeing and in ono yoar a significant incroaso from tho lattor stago until hatching. In 1935 although tho incroaso is indicatod, tho difference is not statistically significant. It is interesting to noto that in ovory caso tho eggs takon in 1935 from fish which our studios would indicato woro tho progeny of thoso from which tho oggs woro takon in 1933, aro significantly largor. Tho boaring of such rosults on practical hatchory work is ovidont. If such a condition oxists goncrally tho ostimato of tho numbor of oggs por quart A.L. Pritchard No. 41 made at the time when the eggs were taken, would be too small if applied at the "eyed" stage. In addition it is proven that the size of eggs from fish of a given stream may vary significantly from cycle to cycle.

A.L. Pritchard No. 42 Bacts Concerning the Life History of the Coho Salmon (Oncorhynchus kisutch) in the Commercial Catches in British Columbia as Determined from their Scales.

The scales for the present study were collected during the course of comprehensive tagging programmes which were carried out on the Coho salmon from tho year 1927 to the year 1931 inclusive off the coast of British Columbia from Langara island in the north to tho strait of Goorgia in the south. In all 6,721 samples have beon examined. Of thoso 409 or 6.1 por cont woro impossible of interpretation due to tho fact that tho scales which woro mounted woro slightly damaged. An analysis of tho ago composition of tho remaining 6,312 is submitted horowith.

Timo spent in ta?o Migrate to JTrosh Salt Numbor Por cont see. as wator wator of total

21 fry 1 to 2 mo. 2 yr. (approx.) 7 .11 22 yoarlings 1 yr. 1 yr. (approx.) 7 .11 31 fry 1 to 2 mo. 3 yr. (approx.) 11 .18 32 yoarlings 1 yr. 2 yr. (approx.) 6,179 97.89 33 . 2~yoar-olds 2 yr. 1 yr. (approx.) 2 .03 41 fry 1 to 2 mo. 4 yr. (approx.) 4 .06 42 yearlings 1 yr. 3 yr. (approx.) 46 .73 43 •• 2-yoar-olds 2 yr. 2 yr. (approx.) 54 .86 Oldor types 2 .03 6,312 100.00

It is thus demonstrated that almost all (97.89$) of tho cohos takon in tho commercial catches in British Columbia fall into tho 32 ago group, i.e. remain in frosh wator for ono yoar, migrate to soa as yoarlings in tho spring of tho second yoar, and appear in tho fishory in tho sumnior and e.utumn of tho third. It is to bo oxpoctod that individuals would occur which havo tho samo frosh- wator rosidenco and spend only part of ono yoar in salt wator (2g). Tho aston ishing fact is that only sovon of this t«>po out of tho total of 6,312 (.11$) havo como to light. For tho first time thoro is rocordod tho discovery of cohos which havo remained one yoar in fresh wator and almost throe in tho ocoan (42). Tho rosults of tho analysis also show that 22 out of tho 6,312 salmon examined loft frosh wator as fry and spont the remainder of thoir lifo in tho soa. Of theso sovon had spont almost two yoars in salt wator (2-^), olovon had A.L. Pritchard ' * No* 4S remained for almost three (3X), and four had lingered into their fourth (4i). The latter once again confirm the assumption that this species may reach an age of more than three years. Srom the results of marking and examining scales from a number of young |P^N coho salmon at Cultus lake, B.C. under the direction of Dr. B.E. Poester, it has been conclusively demonstrated that the type exists which spends two yoars in fresh wator and part of ono yoar in tho sea (33). Our collection of scales havo brought to light individuals having a two year frosh-wator rosidonco fol lowed by two years in salt wator (43). Two scalos havo boon examined which soom to indicate that in extremely rare casos coho salmon may attain an ago oven groator than four years. With out furthor ovidonco, howovor, it would bo unwiso to draw any dofinito con clusions on this mattor.

A.L. Pritchard No. 43

Factors Ihfluoncing tho Upstream Spawning Migration of tho Pink Salmon, Oncorhynchus gorbuscha (Walbaum).

A3 part of tho comprehensive programme to obtain information on the effic iency of natural propagation for the Pink salmon, the upstream migrating adults are carefully examined and counted at a fence installed for the purpose in McClinton creek, l&sset inlet, B.C. At the same time records of daily rainfall, the water height in the creek and temperature are recorded. An analysis of the data for the autumn of 1932 and 1934 has produced tho following correlation coefficients:

Coefficients of Correlation between DAILY COUNTS OF IvIEGRANTS and 1932 Aug* 25 - Oct. 2 Maximum daily wator height .72 i .052 Daily rainfall .85 i .030 1934 Aug. 18 - Oct. 11 I&ximum daily wator height .25 | .085 Daily rainfall .49 i .069 Aug. 18 - Oct. 3 Jfeximum daily water height .51 + .073 Daily rainfall •74 i .044

In every case with the exception of the water height for the full period of the run in 1934 ( .25 i .085) the coefficients aro positive and significant being more than six times thoir own probable error. In 1934 aftor October 3 tho supply of fish off tho mouth of the crook was exhausted and thus ovon though tho water did riso, migrants did not appoar in any numbGrs. We may thus conclude that tho numbor of adult pink salmon migrating daily from tho soa to tho spawning areas in McClinton crook is positively and significantly cor related with tho maximum daily water height in tho crook and tho daily rainfall. This correlation is evident ovon though extreme froshot conditions may reduce ffp1^ or arrest migration. In this short stoop coastal stream1a positivo significant correlation A.L. Pritchard $0. 43 exists between the maxlnum daily water height in the creek and the daily rainfall. Records of temperature included readings taken daily at approximately 9.00 A*Hi and 6.00 P.M. Prom this data no definite effect of changes in temper ature in producing a run can be demonstrated. No final conclusion, however, shouBd be reached in this connection until moro comprehonsivo data are examined.

A.L. Pritchard No. 44

Course of Instruction for jfeshoraion - Nanaimo - February 1936.

A series of lectures was dolivcrod by the staff of tho Pacific Biological Station and othors to fishermen who woro chiofly trollors bolonging to tho B.C. Trollorsf Association, in Nanaimo from February 10 to Fobruary 13, 1936. Dr. D.C.B. Duff roviowod briofiy the olomonts of bacteriology, tho rolation of thoso forms to spoilago, and tho known romodics for this condition which in- cludod improvements in stowage methods* Dr. J.L. Bart prosontod tho availablo knowlodgo concerning tho lifo kistories of tho pilchard and herring and tho fisheries which had boon established for tho two forms concisely tracing tho complicated interrelationship botwoon thorn and othor commercial fish, a connec tion which seriously complicatos any unprojudicod attempt to work out a rational inclusive measure of conservation. Mr. J.P* Tmlly discussed in detail the food valuos of tho various spocios of salmon, Following this ho oxplainod tho studios of tho contont of soa watGr, tho determination of tidos and currents, otc, sug gesting tho probablo rolr.tionship of such studios to the solution of fishory probloms. Dr. C.H. Slsoy introduced tho question of marino wood borors by touch ing briofiy upon thoir lifo histories, tho poriod of infestation and tho offic iary of tho various provontativos which had boon tostod. Mr. G.V. Wilby by moans of lantern slides and brief verbal iiotos covorcd many of tho coinmorcial and non-commercial fishos of tho coast. Filling in botwoon tho locturos men tioned above, tho writor touchod upon cortain facts of olemontary biology, tho anatomy and functions of various organs and organ systoms of fish. Tho discus sion of salmon included spawning bohaviour, the habits of tho young, marking of tho young, efficiency of tho various methods of propagation, and tho bohaviour of tho adults as discovored from tho tagging programmes. The international as pect of all salmon problems was stressed. That effective international co operation could bo onlistcd for tho successful solution of such problems was domonstratod through tho roviow of tho organization and tho work of tho inter national Fishorios Commission on tho halibut. Tho informal talk on tho rolation of predators to thoir proy as ono of the difficult questions facing tho consor- vationist, brought about a difforont view and now understanding of this con troversial situation. The following is a timetable for the course:

Feb. 10. - A.M. Dr. A.L, Pritchard Introduction and Elementary Biology - P.IvI. Dr. D.C.B. Duff Elementary Bacteriology - Evening w "' w » " Bacteria and their Relation to Fish Spoilage Feb. 11. - A.M. Dr. D.C.B. Duff Methods of Combatting Fish Spoilage from Bacteria - P.M. Mr. J.P. Tully Nutritive Value of Salmon A.L. Pritchard No- 44 Feb. 11 - P.Hi Dr. A.L. Pritchard External Features of Fish - Evening Mr. J.P. Tully Ocean Conditions Feb. 12 - A.M. Dr. A.L. Pritchard Orgar. . Systems of Fish - Anatomy and Physiology - P.M. Er* J.L. Hart Pilchards and Herrings - Life Histories and investigation - Evening Dr. C.R. Elsey Wood Borers - Life Histories and Peeven- tive Measures Feb* 13 - A.M. Dr. A.L. Pritchard Halibut Investigations Phases of Conservation - P.M. " " " Life Histories of Salmon Salmon Investigations - Evening Mr. G.V. Vfilby Fishes off the British Columbia Coast At least two indices of appreciation and interest were in evidence, the first the fact that the attendance remained at slightly over twenty for the four days without any sign of coercion, and tho second tho requost immediately after the course was finishod, that another bo considorod for tho autumn at tho timo when tho annual mooting of tho organization was being hold. It is rocommondod that such courses should bo continued in viow of thoir groat mutual boncfit. Thoy bring about closo co-operation with tho fishormon and thoir organizations, thus producing in tho fishormon tho nocossary sympathy and undorstending to allow thorn to givo to tho scientist much of tho detailed information which has boon obtainod as tho rosult of long oxporionco and which is invaluablo in tho solution of fishery problems.

A.L. Pritchard No. 45

Course of Instruction for Fishorrxn - Nanaimo - Novombor 1956

As a rosult of tho interest ovidoncod by the mombors who attondod tho courso of instruction givon in February 1936, tho B.C. Trollors* Association roquostod vory strongly that another of a similar typo bo hold in Nanaimo from Novombor 23 to November 26 inclusive which poriod would fall iixiodiatoly aftor thoir annual mooting when all members should be assembled in that city. Tho courso was chiofly concomod with two subjects, viz,- fish spoilage and handling, and navigation. Dr. N.LS. Carter, tho diroctor of tho Pacific Fishor- ios Experimental Station, prosontod a simplifiod yot comprehensive account of tho causos of spoilago in fish and somo ronodios and preventatives thorofor. Tho lattor subject brought up tho discussion of tho principlos of refrigeration, rofrigeration media, stowago of fish in vessels and insulation. TMs locturor also cloarly outlinod many of tho othor phases of tho work boing carriod for ward at tho Pacific Fisheries Experimental Station. Cr.ptain J.A. Phillipson of tho Harbor Office, Victoria, B.C., Introduced tho subject of navigation stressing particularly thoso phases which concomod those fishormon, viz.- tho intorprotation and demonstration of tho Rules of tho Boad, tho uso of tho com pass and its adjustment, tho application, of compass corrections in laying out courses, tho reading and use of charts, and tho taking of bearings. Mr. J.P. A.L. Pritchard No. 45 Tully troatod with the subject of ocoan curronts pointing out tlic different typos and their offoct. D-. U.A. Ciorxns, tho Director of tho Pacific Biological Station, indicatod tho general air.; of tho work at his station showing the boar- ing of tho research alroady done and that in progress on tho fulf ilmont of tho objoctivos.

Tho following is a tine tabic for tho poriod of tho courso:

Nov. 23 - A.M. Dr. A.L. Pritchard - Introduction - gonoral - P.ii Dr. N.K. Carter - Causos of spoilage in fish - Evening Dr. N.1.1. Crrtor - Vtork of Pacific Fishorios Sbcporinon- tal Station Nov. 24 - A.H. Dr. N.M. Carter - Stowage of fish - P.M. Mr. J.P. Tally - Ocoon curronts - Evening Dr. W..1. Cloneas - Vbrk of Pacific Biological Station Nov. 25 - A. IU Dr. H.M. Carter - Refrigeration media — P. AI. Capt. J.A. Phillipsen Navigation - Evening Capt. J.A. Phillipsen Navigation Nov. 26 - A. 14 Capt. J.A. Phillipsen Navigation - P.M. Capt. J.A. Phillipsen Navigation - Evening Capt. J.A. Phillipsen Navigation

The attendance gradually rose from eleven in the first lecture to as high as twenty-eight at one of the evening discussions. Tho usual number attending was from sixteen to eighteen. Tho fooling was gonoral that information of groat benefit to tho fishermen had boon obtainod and that furthor courses woro groat- ly to bo dosirod. W.E. Ricker No* 46 Iimnological Investigations on Cultus lako, in Relation to tho Survival of Sockoyo Salmon-. During 1936 somi-monthly tomporaturo sorios and plankton hauls havo boon con tinued at a. central representative lake station. Following tho cold woathor in February and oarly Xhrch, tho lako was cooled to tho lowost tomporaturo on rocord. During fino woathor immodiatoly following, stratification was ostablishod and tho lower part of tho lako bocamo isolatod whilo its tomporaturo was still as low as 4.1°C.? with the rosult that it ro- mainod about a degroo colder than usual throughout tho summer and autumn. Tho cold of oarly spring and rapid warning thereafter providod a valuablo opportunity to add to existing observations on tho rolation of sockeye migration to temper ature. Tho plankton collections havo not boon enumerated as yet, but aro oxpoctod to provide useful information as to whether tho prosonco of dead salmon car casses in Cultus lako is of importance in affecting the abundanco of animal plankton, which is tho food of tho young sockoyoc

W.E. Ricker No» 47

I. The Food of Char (Salvelinus spectabilis) in Cultus lake.

2b the information on food of char obtained in 1932-34 can now be added the results of examination of 461 stomachc of fish taken during 1935 and 1936, of which total 173 contained food organisms. Very few char were caught from October 1935 to Iferch 1936 inclusive, and they were invariably empty of food. As before, the char were shown to be piscivorous almost exclusively, and the list of fish eaten includes almost all snail to modium-sized fish ^mjhe lako: sockeye and c^htf"$a,!mDnf~ (Ccttus aspor, £« alouticus), and stickleback. Of tho throe commonost spocios, the sticklebacks woro takon tf^tBgrET"*^ sparingly in late summer and autumn; the ALeutian sculpins were found from May to Soptembor, boing most frequent in July and August, and apparent^ moro frequent in 1935 than in 1936; tho sockeye woro found throughout the whole poriod (ftiay to October), probably moro common in 1936 than 1935. Of tho loss common spocios, tho daco occur in nearly every month, as do also tho largor sculpin. Trout, coho, squawfish and suckers each occur only in ono or two stomachs. During somo of tho summor months it was possiblo to compare tho foods of different longth groups of char. Thus in 1935 largo char (moro than 500 mm* long) consumed a much groator proportion of largo fish (principally Cottus aspor and sockoyo ovor two yoars old) than did those of medium sizo0 In 1936 a con siderable numbor of small char (loss than 300 mm* long) woro examined and thoso confined themselves ovon moro strictly than modiun-sizod onos to tho smaller fish, principally sockoyo in thoir first year of lifo„ As tho small char con tained a greater volumo' of fingorling sockoyo por stomr.ch, and thoro woro among thorn fower empty stomachs, it soons cloar that thoy e.ro at that e.go moro dos- tructivo to potontial migrants than whon largor© W.E. Rickor No. 48 XI* *" g°°d °f GuUh™* «""* ^™ ^arkii) m cm.,,, t.w.

found tojMB-STioSSt ZfS£' T? 422 oontained f°°a. 0» trout were

in thoConsideringsnrinp" oftrU^oTSi^o^o!l9Sfi thmr ««•»«. *„ ,, - 99 STlongffir^nliXUIl»' ursx, wnon firstrstVtakon midgos;fish n ?mK T„r^Sdo<„ up *^Xof^i*-^!1??-** lr i00a at xlus !?*timo' l£re°1*o roaaindornU*°r ofbeing^

S^° ^ S^V ^ ^f^tion of sockoyo in April mado the bo fish moro readily c^sod+h^2«l.hL ^chr^ctorizodwas .Tt^n ?* ^^ ™^ extraordinary^ t3" C™P^abundenco ofofsticklebacks^wingod ants in stLkSv?'stickleback) soom Tinsignificant.tho.*onSUilpti°n% oarlyo* ottoJunoinsectsthoy hadandgreatlyfish (sockoyo,declineddace,howl ever, andfrom mid-Juno onward to October, fish were tho only items of any iL +£^ ^ th0 *pout s f00d- 0f ^oso, ^kcyo invaria.bly bulked largost, and woreworo s«L?o£r>stickleback, 7°dace,n0V°rsquawfisn^ thcnand 4/5sculpinof th°{Cottust0trJ"aspor),f00d- **in order°thorof-P^iosdo oreasing importanco. For the corresponding months in 1935, the food picture is much the same. ^^Srt^hadnothing by the endr1^**7of June. beQ1Regardingpped0Blinan1;the summerin **&>and^ autumndeclinedfishtoconsumption,practically nottlSLronly wore 2*they S°Ckey6exceododWerein bulknot bytakettthenoar1^sticklebacks,s0 ^oquentlybut thoasavoragoin 1936,volumofor or stomach content was loss in cvory monthc «, ,^Ut,Sina^0r than th° ab0vc (200~299 **•) took relatively more insocts in lZZ.+S?\ ^7 aJoaJmost nothing but midgo pupao in Ifarch, changing to land insocts in April and toy. M interesting item of thoir food in Juno and early July was tho largo numbor of vory snail fry of tho sculpin (Cottus espor) - averaging sovoral hundred per stomach, Sockoyo woro thoir pSSTiOfooa in summer and autumn, but in Soptonbor there was a period whon land insocts woro again of importanco. m* ^^J***** thm 40° ^ *ls0 difforod somewhat from thoso of modium sizo. Thoy ato fowor insocts and moro fish. Of tho fish takon, thoro was a greater ™?Z J? °f ^°tG.°f 1PXg°r SizC ^-^sh, 1-rgo sculpins (Cottus aspor), and of tho small but spiny sticklebacks, which tho smaller trouFaiio^Ftoavoid.

W.E. Ricker ~ ,n No* 49 &o Eood of tho larger Coho Salmon (Oncorhynchus kisutch) and Sockoyo Salmon (0. norka) in Cultus Ir.ko. " * ^ Coho woro takon in tho nots along with tho trout, boing much moro common in spring than at othor timos. Of 244 stomachs oxaminod, moro than throo- quarters woro taken in Ifech and April, 1936. Tho groat majority of specimens W.E. Rickor No. 49 at that time woro boginning thoir third yoar of lifo, and woro 250-350 mm. long. Iator in tho yoar specimons in thoir second yoar woro moro froqucnt. In general tho food of tho coho throughout tho yoar was similar to that of trout of tho samo sizo. In lifcrch midgo pupao bulked much groator than all othor foods. In April thoy woro still common, but nixod with moro land insects, a littlo plankton (Daphnia), and a considorablo volumo of sockoyo salmon. Tho single Jfey specimens had caton wingod ants, which woro. also common in trout at that tine. Iron Juno to October fish wore tho principal food of both ago groups, among which only sockoyo woro rocognizodo A small number of sockoyo salmon, in thoir second and third yoars of lifo, woro token during tho spring and summer of 1955 and 19360 Polagic plankton or ganisms, ospocially Daphnia, woro tho principal food of both ago-groups. Two of tho largor ones had oaton soveral fingorling sockcyo0 M--ny maturing spocimons woro token in autumn, at which timo thoy containod very littlo - a small amount of plankton or a fow midgo pupao at mosto

W.E. Rickor No. 50

IV. The Eood of the Squawfish (Ptychocheilus oregonensis) in Cultus lake.

Erom June, 1935 to October, 1936, a lar.se number of squawfish were avail able for stomach analysis; about 3000 have besn actually examined, and of these 800 contained food organisms in the stcmach0 In general, pronounced seasonal and annual fluctuations in kinds and quantity of food consumed characterise the diet of this species. During the summer of 1935, plankton wao the most characteristic food of medium-sized squawfish (200-299 mm.}; it increased from 9% of the total in June to 60$ in August and September. Next in importance wore sticklebacks, which bulked as high as 57$ in July: land insects woro dominant in^WiPirst half of Juno; sculpins, daco, sDekoyo and snails mako up tho remainder. With tho be ginning ' df'OctcbSrY^planl^o^ almost disappears, ait tho various fish and invor- tobratos romain, with sticklobacks still commonest; to thoso is added a now itom: fishj^ggs, presumably of achar, as tho salmon woro not yot in tho lako. AT-tor October 15 thoro woro no^moro nottod fi'sh^a~va:ilaT^ alysos woro of fish caught on baitod hooks3 At this timo too, a largo numbor of salmon ontorod tho lako, spawned and diod. Of tho squawfish token in Novombor and December, about half woro from tho salmon rc&ds; it is not surprising there for© to find salmon offal tho most important food of the spocimons examined; a few had taken considerable numbers of salmon oggs, and forage fish woro still pursued by somo. In January, February and oarly Ivhrch tho fow squawfish taken woro almost all ompty of food. In lato ifcrch and oarly April fish and a fow sne.ils woro takon; all tho usual forago spocios woro woll roprosontod, but thoy woro oxcoodod in bulk by tho littlo lamproy, Lampotra a^TOsii. In tho sovon days from April 24 to 30, at which timo tho seaward migration of sockoyo was at its hoi^ht, thoso salmon constituted almost tho whole of tho squawfish stomach contents. With tho turn of tho month howovor came an abrupt change: sockoyo woro only foobly roprosontod in oarly Ifey, and tho bulk of tho food was of torrostrial in- W.E. Ricker No. 50

sects, largely winged ants. Throughout the balance of lay insects were impor tant, with an increasing proportion of aquatic forms, largely caddis larvae; in June they became less so, and plankton first appeared, l&antime the propor tion of forage fish increased to become the principal summer food including sticklebacks, dace, sculpins. One sucker was found and sockeye were rarely taken during, summer. It is noteworthy that plankton was apparently not nearly as important in 1936 as in 1935. With September tho proportion of fish in the diot changed to include ovor 50$ sockoyo, and in October this increased to 90$; in striking contrast to tho preceding year, when sockeyo did not oxcood 2$ in either of thoso months. Tho food of squawfish larger than 300 mm., in so far as spocimons woro avail able ovor this poriod, rosomblos that of tho modium-sizod fish in most ways. Tho proportion of invertebrates was however usually loss; plankton particularly was much loss common. Tho food of small squawfish - loss than 200 mm. long,- has not yot boon ox- aminod in dotr.il, but appoors to contain moro plankton, moro insocts, and fowor fish than thoso of largor sizo.

W.E. Rickor No. 51

V* Tho Food of Rocky Mountain Whitofish (Prosopiun williamsoni), Columbia Chub (Mylochoilus caurinus), suckor (Catostomus macrochoilus) and sculpin (Cottus aspor) in Cultus lako.

Twenty-three stomachs of rocky mountain whitefish were examined in 1935 and 1936, the majority of them being empty. Six specimens taken at various seasons had eaten caddis jaryae for the most part, some small snails, and in one case colonies of the^bT^^^een alga Nostoc. No confirmation was obtained of an ear lier observation that whitefish will at times take very small sockeye fingorlings. Thirteen stomachs of chub were obtained in the same period. The stomach and intestine of six of them contained sn&ils as the only recognizable food. Mary suckors of medium to largo sff^Twore availablo at various poriods of 1935 and 1936, and a good numbor of stomachs woro oxeminod. So large a propor tion of those provod to bo empty the.t it bocamo nocossary to adopt the less satis factory mothod of using intestinal contents as an indication of tho food of tho spocios. Specimens taken during winter had oaton bottom organisms of tho lako (caddis larvao, mayfly nymphs, snails and Hyalolla), with somo plant remains and plankton organisms. In February Bryozoa bocamo moro common than any of tho othor forms. During Ishrch and April plankton bocamo rolativoly moro important, it being tho principal food in tho lattor month. Summor rocords aro too scanty to bo of much intorost but one spocinon taken in Juno had oekton oggs of tho dace (Richardsonius baltoatus) • It should bo noted the.t a considorablo numbor of stomachs woro examined at the tino of tho omorgonco of sockoyo fry from tho rodds, (April) and a few at tho timo of spawning (Novombor and Docombor) but neither oggs nor fry woro found in tho stomachs. Sculpin woro takon sparingly in gill-nets in Soptombor, 1935, moro abundantly on sot linos or in cago traps from Octobor to Eobruary, and in gill-nets thoro- aftor. Tho not-caught fish woro usually of lergc sizo (approaching or oxcood- ing 200 mm.), whilo thoso from tho linos end traps avoragod about 130 mm. This W.2* Rickor No# 51

sizo difforonco is at loast partly responsible for tho prodominanco of fish (sticklobacks, daco, or even smallor £. aspor) in tho Soptonbor spocimons, and of invortobrato organisms (caddis larvao, mayfly nymphs) in thoso takon during tho .winter. Of 58 spocimons token from tho redds whoro socle eye woro spawning in lato Novombor and Docombor, 1935, two contained a vory fow salmon oggs. Sovor al had consumod flosh from tho carcasses of tho doad salmon, but tho majority woro onpty. Unfortunately no adoquato collection could bo mado at tho timo of omorgonco of tho fry, in April. Of tho occasional spocimons taken in tho nots from M?rch to Soptombor, 1936, tho smallor ato bottom insocts and snails princi pally whilo tho largor subsisted on fish and, in two ca.sos, a. small lamproy.

W.E. Rickor No. 52

VII. Tho Consumption of Sockoyo by Cultus lako Predators, in Rolation to tho Ave.ilablo Supply.

In comparing the stomach contents of predators in 1935 and 1936, the most outstanding difference is the great increase in consumption of fingerling sock eye in the later year. The increase is most marked in the case of trout, when the average number per stomach increased by from 4 to 18 times in various months from June to October. In the case of squawfish, June shows no increase but the September and October increase is just as great as for the trout. The char like wise show an increased consumption in every month, but the average number is not more than twice as great as in the corresponding 1935 period; the data are however so scanty that no satisfactory comparison is possible. Tho data concerning sockeyo population in Cultus lako in 1935 and 1936 show that whereas in the former yoar, tho fry hatched from 3,000.000 plantod eyed eggs presumably formed tho supply, in tho next year, a natural deposition of 40,000,000 oggs constituted tho basis of tho 1936 fry and fingorling group. In othor words, tho presumed sockoyo population in tho lake in 1936 was roughly from ton to thirteen times as large as in the previous yoar0 Hence there would be available to tho predators a much larger number of sockoyos por individual, particularly sinco tho predator population was boing systematically roducod by netting. Studios mado in oorlior years soor.od to show that consumption of sockoyo by predators and tho spring seaward migration of sockoyo wero approximately proportional. Tho migration in 1935 amountod to roughly 495,000 sockoyo, and if, as the comparison of stomach contents of 1935 and 1936 reveals, tho consumption of sockeyo by predators in 1936 was ton timos that of 1935, tho migration from tho 1936 sockoye population should approxime.to 5,000,000 individuals. There are, of courso, cortain conditional factors operating which must be considered, but tho count of migrants in tho spring of 1937 will indicato how tenable tho above assumptions provo to bo. If 5,000,000 migrants occur, thoy will roprosont a survival of approximately 12.5 por cont, a notable increase ovor provious returns from natural spawning. A.L* Tester No. 53 toie Sampling of the Commercial Catch of Herring, The purpose of sampling the commercial catch is firstly to determine and, if possible, to prognosticate, the annual changes taking place in length, age and abundance; and secondly to determine the extent of intermingling and migra tion of herring. As a general survey of these problems has already been made, sampling during the season 1935-36 was confined to the south-oast and west coasts of Vancouver island to determine mora exhaustively what fluctuations in longth and age are taking place and to determine tho homogeneity, limits, and stability of specific populations. A curtailed fishing season and tho authorTs absonco from tho Station rondorod difficult tho task of srxiplingo Tho colloction which was made includes throo samples (527 fish) from Saltspring island and sovon samples (773 fish) from Barkloy sound0 Tho standard length of the Saltspring island herring avoragod 196*2 mm»,- tho largest valuo obtainod ovor a period, of sovon yoarsf, Tho avorago longth for Barkloy sound was considerably less,- 162.5 mm., This value is similar to those obtainod in previous years for the samo locality0 The porcontago ago compositions in tho two rogions arc as follcws i

In year of ago

Locality " II III IV V VI VII VIII IX Saltspring is. 1,3 39.9 31„5 20,5 1*3 4,2 1*0 0.3 Barkloy sd. 206 66.0 16.7 13,,.I 1*3 001 0*1 Tho exceptionally large percentage of fish (37o3) over age IV accounts for the large averega length of the Saltspring island fish0 The percentage of V?s is the largest encountered in seven years* This yoar class (1931) has been considerab ly above average strength sinco it entered tho fishery as IIIrs in 1933-34. An other rich yoar class, that of 1929. is rclativaly woll-roprosontod as VII's in 1935-36. Tho results suggest that tho number of older fish in tho catches is tending to incroaso as a result of tho £ocroasod fishing activity during the past throe or four yoars. The exceptional].:: largo percentage of Ill's in tho Barkloy sound samplos indicatos that a yoar class (that of 1933) considerably above avorago strength entered tho fishory in forco during tho pest soason. Racial studios on the populations havo included a consideration of vortcbral count, sex ratio and rate of growth,. As has usually booh tho case in past yoars, tho total vortobral counts of tho samo yoar classes at Saltspring island and in Barkloy sound woro not significantly different. However, the abdominal count was significantly lower in the ferror locality (23*006 as compared with 23,262)0 Tho porcontago of tho soxos was also considerably different in tho two local ities, malos forming 5909 por cont at Saltspring island and 47.2 por cent in Barkloy sound. On tho avorago the ir.tc of growth of tho oast coast fish was slower than that of tho wost coast fish, Ail cf tho above rosults confirm thoso of previous years and provo that tho herring of tho two localities form, essen tially distinct populations* Sufficient data aro not available as yet for a detailed study of tho racial characters of oach population* It is rocommondod that sampling bo continued in future years in ordor to holp solvo tho probloms of dominating yorv:* classes and migration, as thoso e;ro of considorablo importance both to mombars of the industry and to tho adminis trators of tho fishery. A.L. Tester No. 54

The Spawning of Herring in British Columbia from 1929 to 1936>

Each year since 1929, fishery inspectors in the various districts have forwarded reports on the spawning of herring. Considerable information has boen Jp^ extracted from those concerning tho location of tho spawning grounds, tho time and duration of tha spawning poriod, tho intensity of spawning and the mortality of the oggs. Spawning takes place in practically all areas throughout the coastal wators of tho province and almost invariably tho eggs are deposited on vegetation in or just bolow tho intortidal zone* Grounds aro locatod on tho outor oxposod coast, in protoctod channels and bays, and at tho hoads of long inlots. In thoso divorso habitats tho oggs dovolop undor a variety of physical and chemical conditions. Thoro is groat variation in tho area of particular grounds, somo extending for but a fow yards and others covering sovoral miles of shorolino. 5rom observations mado over the 8-yoar poriod it would soom that tho tomporaturo of tho wator is not a primary factor in determining tho location of tho spawning grounds. In most localities intensive spawning takes place during the month of March, although spawnings in February and April are common, and spawnings in January and.Jfoy have been reported occasionally. The on^ authentic record of summer spawning is for l&sset inlet in July. Although there is but a slight tendency for spawning to take place later towards the north in British Columbia, never theless there is a trend in this direction when times of spawning along the whole coast of North America are taken into consideration. Still more marked is the tendency for tho spawning poriod to become of shorter duration from south to north. This observation which has not boen previously recorded is a possible explanation of the moro marked appearance of tho phonomonon of dominating year classes in northorn wators. In cortain districts within tho provinco thoro appears to bo scoo regularity in tho occurronco of spawning herring on particular grounds. Com.para.tivo ostimatos of tho intensity of hoa.vinoss of spawning havo boon mado for oach area. Tho intensities vary considorably in tho samo locality from yoar to yoar and anong tho various localities in tho samo yoar. A positivo cor relation (r r 0.6l) botwoon tho intonsity of spawning and tho relative abundanco of tho rosultant yoar brood has boon obtainod and this is on tho borderline of statistical sigiificanco (P - 0.06). If tho correlation can bo dofinitoly os- tablishod in futuro yoars, it will show that in iho British Columbia herring, tho success of a yoar class doponds to a. largor oxtont on tho numbor of oggs which hatch and to a lossor oxtont on tho mortality during tho larval poriod than in most other herring racos. If this bo so, tho mortality of tho oggs on tho. spawning grounds becomes of groat importance. improbably storas constitute one of the greatest sources of mortality on the spawning grounds. In 1935 on both the east and west coasts of Vancouver island large quantities -of eggs were pounded by waves and driftwood and were washed ashore from exposed beds. At least a large percentage and possibly all of these eggs die. Estimates of the loss on particular grounds ranged up to 80 per cent of the total number of eggs deposited, In certain localities the feeding of water fowl of various species results in a high mortality, apart from the action of storms in placing the oggs within their roach. At Kyuquot sound, A.L. Tostor No. 54 from 5 to 100 por cont of the oggs on individual grounds havo boon consumed by gulls, ducks and scotors. In othor locolitios whoro those birds aro loss numer ous tho mortality is smallor. Thoso sourcos of mortality will probably havo to bo takon into consideration in attomp ting to assay tho annual productivity of tho spawning grounds in oach districto As tho abovo obsorvations havo an important bearing on tho problom of fluc tuations in abundance it is recommended that the collection of spawning reports be continued in future years. To aid in analysis and insure the inclusion of all necessary details, it is suggested that a blank form with appropriate head ings be prepared and distributed to tho inspectors to be filled in each yoar.

A.L. Tester jjo* 55

Catch Statitics of the Herring ffishery for 1955-56.

The primary object of collecting daily catch statistics is to obtain a measure of tho availability and abundance of herring which is compa.ra.blo from yoar to yoar* Tho unit adopted is tho avorago catch per soino por day of active fishing* Tho total rocordod catch on tho scuth-oast coast of Vancouvor island by five doublo soinos amountod to 13,865 tons* Practically all of tho fish woro takon from Swanson and Satellite channels* Tho records indicate that harring woro oithor most abundant or most readily captured during tho fourth week of fishing (Oct. 21-26). As shown by tho following figures tho.avorago daily catch por soino was higher during tho past season than in oithor of tho two previous years: 1933-34—67.2 tons; 1934-35—75„8 tens; 1935-36—89*4 tons. These re cords indicato e. gradual incroaso in tho abundance of horring in tho Saltspring island fishery. This, incroaso is probably rolatod to tho rocont trend in ago composition noted olsowhoro. On tho west coast of Vancouver island tho catches were as follows: Berkley sound—over 12,000 tons; Nootka sound—3,093 tons; Kyuquot sound--9,764 tons. The reward per unit of effort (singLe seines) amounted to 39o0 tons in Barkley sound, 134*5 tons in Nootka sound and 11796 tons in Kyuquot sound. Although the figures for Barkley sound are based on but a portion of the total catch, they indicate that herring were much less abundant in this locality during the fishing season than in both Nootka and Kyuquot sounds to the north* They were also relatively less abundant in Barkl? sound in 1935-36 than in 1933-34 and 1934-35 when averages of 46.5 and 60.4 tons wore obtained. Othor sources of information indicato that the fish wore abundant at tho close of the fishing season but below avorago abundonco at spawiiing time during the past year* It is only through tho continuous collection of these daily catch statistics in future years that reliable inforinatioiT. can be obtained on what fluctuations- in .availability and abundance are taking place at the various herring fishing grounds. J.P. Tully No. 56

Ocean Current Survey

An investigation is being made of the ocean currents off the Pacific Coast of Canada with their tidal, seasonal and annual variations, so that their effect on the fisheries may be determined by. correlation with the current Biological inves tigations. The results are being presented in a complete chart system. From the oceanographic investigations that have been carried on at this station during the past four years, it can be stated that there are three major current factors in waters within a hundred miles of tho coast* First tho land drainage which is greater in the summer than the winter, and constitutes a seasonal factor in the variations in the coastwise current system. Secondly, there is a northerly flowing coastwise current which is rogardod as a resultant of tho prevailing wostorly trade winds, and as consisting largoly of upwelling deep wator. It is characterized by rolativoly constant low tompor aturos ( 7° to 11°C.) tho yoar round at tho surfc.co of tho soa. Thirdly, to soaward of this thorc is a surface current, which is noticeably warmer in tho summer (17° to 19°0) than tho coast waters, and is variable with tho prevailing winds. The difference in salinity botwoen the surface wators of tho latter two curront systems is not groat but tho rato of incroaso of salinity botweon ton metres dopth and tho bottom is much greater in tho coast wator than in tho open ocoan. It may bo prosumod from tho observations that if tho influonco of land drainago woro romovod, tho surface coast wators would bo a]most identical in physical character with tho open sea wators from depths groatcr than two hundrod motros* The range of direct influence of the seasonal land drainage on coast waters is greater in calm weather than in rough. In calm weather it tends to set up a gradient -current flowing northwards, whereas in rough weather it becomes mixed with the upwelling dense water, and tends to bring this latter more nearly to the density of the surface water in the open ocean0 In order to satisfactorily chart the ocean currents in ihis region it is necessary to make dynamic measurements for a sufficient distance offshore to reach the relatively stable wators of tho open ocean* Tho sections should bo spaced sufficiently close to observe at least tho major variations in the direction of flow, /and tho effects of tho throo major factors on tho systeme Tho obser vations should bo ropoatod as often as nocossary to measure tho effects of tho groat tiaal rango on tho gradient curronts, and to detormino the tidal seasonal and annual cycles of velocity, tomporaturo a.nd salinity. During the calender year 1936 there have been four expeditions in HoMeC.S. Armentiers for the purpose of Dynamic Observations, the first extending from February 14 to 28, the second from June 8 to 16, the third from July 25 to August* 8 and the fourth from September 2 to 18* The statistics of these ex peditions are as follows;

Expedition 1 2 3 4 Total Days on board 14 7 13 16 50 Hours observing 48 42 55 24 169 Sections observed 8 3 5 1 17 MLles of section 1115 Number of stations 36 18 36 10 100 J.P. Tally No. 56

Surface charts 4 2 2 1 9 Total charts 12 8 20 .Analyses 50 40 70 14 174 Days to develop data 207 Total time required (l&n days) 381

The first expedition was undertaken to determine the effects of the enormous tide range on the dynamic calculations. It consisted of two parallel sections on the flood and two on the ebb of each of the neap and spring tides. On the second expedition two sections were observed at right angles to the coast, by proceeding 105 miles seaward from Cape Beale and returning landward along the same line. This procedure was repeated on tho third expedition, departing from Nootka* Three other sections wero observed on this expedition,, Tho first by proceeding 108 milos to soaward from Kyuquot sound at right angles to tho coast, tho socond by procooding south-oastward from tho ond of this lino parallel to the coast and about 100 milos offshoro, and tho third by procooding landward into Juan do Fuca strait. On tho fourth expedition a soction was obsorvod between tho outranco to Johnston strait and Capo St. J*mos0 Sufficient data havo been collected to indicato tho curronts off tho entrance to Juan do Fuca strait in tho wintor, oarly summer and midsummer, as well as an outline of the curront systom off tho West Coast of Vancouver island and to wards tho Qjueon Chcrlotto islands, with tho offocts of tho tidal range and phaso, and the offoct of tho prevailing winds. Charts havo boon prepared from those data to show tho surface currents, as well as the currents at 25, 50 and 100 motro dopths which includo tho zono of navigation.and the fishing levols for herring and pilchard, sn1mon...and..halibut.. Td.q offocts of the various tidal phasos and winds aro also shown on soparato shoots* Tho complote work includes 25 charts, 12 showing the.gradient curronts off tho ontranco to Juan do Fuca strait in dotail, eight showing the gonoral current system along the coast-and five showing the effects of the prevailing winds and the tidal amplitude and phase0 Two charts have been published in the last issue of Progress Roports showing the gradient currents on the flood of each of the neap and the spring tides off the entrance to Juan de Fuca strait. Thoso two charts have been presented, as they show the groat differonco botwoon tho direction of tho current on tho spring and Noap Tides. Tho phaso of tho tides affects tho velocity, but has relatively littlo offoct on tho path of tho current but as shown, tho difforonco in amplitudo botwoon tho noap and spring tidos can altor tho wholo charactor of tho flow. Tho results of tho yoars survey will bo presented for publication in tho near future and it is rocommondod thoy together with tho charts bo issued as a bulletin so that tho rosults may bo made available to tho departments of Fisher ies, National Dofonso and Marino as well as to fishormon and rosoarchors, all of whom aro vitally intorostod in tho curronts of tho coast. J.P. Tally No. 57

Observations of the Submarine Msteorological Cycles

It is logical, in view of the suspected cyclic nature of the variations in the physical characteristics that cause the currents in the sea, to observe these cycles as cheaply and as comprehensively as possible. The salinity and temperature of the coast waters can be observed at a number of suitably placed station^^the cycles that occur in the coastwise currents due to upwelling and land drainage can bo ostimated. It is known that the surface conditions of the soa aro largely affoctod by or affect tho atmospheric woathor, and correl ations havo boon established botwoon surface wator tomporaturos and air tom poraturos. This can bo carried a stop furthor and a rolation shown botwoon regional procipitation and surfaco salinity, which in turn may bo usod as a measure of land drainago. Tho effect of this lend drainago may then bo ostim ated by a continuous record of tho wind direction and velocity which sorves as a koy to tho mochanical mixing of tho surfaco layers of tho sea. In this way tho marine and atmospheric meteorological observations sorvo to define the poaks of tho cycles, thoir limits, and periods of chango. A dynamic survey is tedious and costly, but from consideration of the cycles defined in the continuous observations, the dynamic measurements can be reduced to a minimum and made to apply to the whole season instead of being applicable only to the time of observation. This system of correlation of current measurement to periodicity of sub marine and atmospheric meteorological conditions also permits the current charts of one year to be applied with reasonable assurance to another year when the much cheaper continuous observations indicate similarity of physical con ditions. Daily observations of seawator temperaturo, salinity, and the atmospheric temperature, precipitation, and wind force and direction has been carried on continuously at strategic points along the Pacific Coast of Canada since the inception of this program in 1934. From time to time additional points of observation have been created till at the present time there are eleven stations on the Pacific Coast engaged in these observations. They aro listed as follows:

Station Observer Started Atmospheric Data

William Head Capt. J. Hanson 1921 Victoria Amphitrite Lt. C. Fletcher August, 1934 Ucluelet Nootka Lt. T. Fish Soptombor, 1934 Estevan Eains Is. Lt. C. Carver January, 1935 Kyuquot Capo St. Jamos P$ Dohorty January, 1935 Capo St. Jamos langara August, 1936 langara Groon Is. J. Moron January, 1935 Princo Rupert Pino Is. October, 1936 Bull Harbour Capo Midgo October, 1936 Capo Iazo Entrance Is. April, 1936 Nanaimo Poplar Is. January, 1927 Wostminstor J.P. Tally " No» 57

All thoso stations oxcopt the last ono arc observing soa wator at various localities along tho ocoan coast, in tho Hocato straits and Strait of Georgia. Poplar island is usod as a control point for tho observation of tho volumo and tomporaturo of tho-Frasor rivor flow. jpv Thoso data aro boing graphed as described in Progress Roport No. 26, and at prosont aro boing filod. Howovor it is nocossary that thoy should bo mado avail- ablo for tho use of fishorios rcscorchors. Tho mass of date, is too groat to bo includod in any single publisation and it is urgod that thb matorial bo brought up to dato in bullotin form for fivo stations. Only tho graphs of tho data nood be publishod. A sample of tho most suitable form of prosontation has boon prepared for tho annual mooting of tho Biological Board. Horoe.ftor it is urgod that an Annual Bullotin, similar to that publishod by tho Motoorological Buroau bo prosontod, thus making tho data, availablo to all thoso intorostod. Tho cuts can bo prosor- vod for any rosoarchor who wishes to illustrato a particular motoorological cyclic phonomonon in his work.

J.P. Tully No* 58

A Procoduro for Increasing tho Accuracy of Surfaco Current Charts

From somo of tho data collectod on tho 1934 Ocoanographic Expeditions in C.G.S. Ufa. J. Stewart, it has boon shown that if tho surfaco density of tho wator is obsorvod at frequent intervals botwoon tho stations occupiod in a dynamic survey of tho ocean curronts, tho surfaco curronts can bo shown in much groator detail than was normally possible. It is shown that tho winds tond to sot up surfaco curronts in tho ocoan, and thoso in turn cause variations in tho donsity according to tho laws of fluid mechanics. If those donsitics aro obsorvod, thoy can bo usod as a moa.s- uro of tho puroly surfaco curronts in a vory simple mannor. Each surfaco density observed botwoon tho regular dynamic station is treated as a subsidiary dynamic station with a base at ton motros dopth end tho gradient curronts calculatod to this dopth in tho usual mannor. Tho gradient curront at ton motros dopth is dotorminod from tho data at tho regular stations and may bo referred to any e.byssal dopth. Sinco tho cur ront at ton motros dopth is romovod from tho diroct influoncc of tho wind it is moro stable in direction and volocity than tho surfaco curront. Thoroforo tho interpolation of tho curront at the ton motro lovol botwoon rogule.r stations is moro accurato' than that at tho surfaco. Tho surfa.co currents calculatod at tho subsidiary stations is thon super imposed on tho curronts found at ton motros dopth and tho rosultant surfaco velocities chartod. Such a chart givos tho dota.il of surfaco movomont on a groatly onlargod scalo and to tho limit of tho dogroo of accuracy of tho deter mination of tho currents at ton motros dopth. J.P. Tully No. 59

A Graphical Method for Calculating the Corrections on Deep Sea Reversing Thermometers

The tedious operation of calculating the. corrections on deep sea reversing thermometers may be considerably shortened by the uso of a nomograph that has been constructed. There aro two thermoiuotors in one of thoso instruments ono, a reversing thermometer which records tho tomporaturos at tho momont of rovorsal and an auxiliary which is a standard chomical thormomotor on which may bo obsorvod tho tomporaturo of tho thormomotor caso at tho timo of reading. Duo to the fact that tho thormomotor is seldom road at tho exact tomporaturo of rovorsal thoro is a correction to apply to tho reversing thormonctor for this doviation, which is oxprossod by tho formula

C u (T - V0)(T - t)K - whoro C is tho correction to bo applied to tho tomporaturo (T) obsorvod on tho rovorsing thormomotor, for tho tomporaturo (t) obsorvod on tho auxiliary thor momotor and K is a constant. Tho nomograph accomplishes this computation ac curately with a minimum of effort. It is of valuo as unskilled obsorvors can be safely trustod with this othor- wiso todious arithmetical computation. This saves tho timo of skillod scion- . tists which may bo hotter appliod to sciontific mattors than routino arithmetic.

J.P. Tully No. 60 A Graphical Lfothod for tho Calculation of "D" in d*t = ff0 - D (Khudson) The density (6"0) of a sample of sea water at 0°C, and standard atmospheric pressure may be determined from the chlorinity per kilogram (CI °/°°) by refer ence to Khudsens i^drographical Tables (1901) in the form (d - 1) 1000 ((5"0). This value may be corrected for the temperature in situ by adding the quantity D in the expression where 0^ is the density of tho soa wator at norimb pressure and temperature in siiu ((dt - 1) 1000). The valuo of D is given in the hydrographical tables at intervals of one dogroo of temperature and integral valuos of 6Q but arithmetical interpolation for fractional valuos is todious since tho change is not linoar. Sovcral modifications of tho tabic have boon dovisod notably by ifctthows (1932). Howovor those tablos all rcquiro somo arithmetical facility, and in tho hands of inoxporioncod workers orrars aro vory probable, particularly in routino work such as dynamic calculation. A nomograph has boon constructed and has boon proven to bo accurate to tho third decimal placo, (fifth sigiificant firjuro). Sinco dynamic calculations only roquiro tho fourth significant fi@iro, this nomograph is satisfactory, and the probability of orror inhoront in reading table ontrios and performing todious interpolation calculation has boon roducod to a minimum. This graph has not boon prosontod for publication as tho reproduction of the graph with sufficient accuracy for uso roquiros an engraving. Howovor its uso has savod a lot of timo and mr.do it possiblo for unskillod assistants to mako this parabolic interpolation roquirod in dynamical calculations. J.P. Tully No* 61

Service Analyses A numbor of analyses and minor investigations aro made every yoar as service to othor investigators and to answer industrial queries. Somo of tho most important of these aro listed as follows. Eighteen samples of lako plankton collected by Dr. D.S. ft-wson, from British Columbia lakes woro analyzed for dry weight and protein nitrogen con tent. Kitrogon analyses woro mado on toclmical forme.lin to dotormino its suita.. bility as a prosorvativo for plankton which is to bo analyzed for nitrogen. Tho two samples tostcd gavo no indication of nitrogen. Complete chemical analyses woro mr.do of Okonagon lako we.tor and tfe.tch lako water. Tho first for Drc-. R-.wson and the latter for the Dopartmont of Fisheries. Tho Station laboratory is not properly equipped for frosh water analyses and in consequence such analyses aro rr.thor timo consuming and oxpon- sive. .Analyses wore mr.do of waste oyster liquor, from Deop Bay Gannory, for proteins, as on indication of tho food valuo of tho wasto material. This was found to contain 3.7 parts por thousand of protein. Analyses of Crystal lako wator and mineral being deposited along tho lako shores wcro mado for tho Dopartnont cf Fisheries, Analyses woro carriod out of tho waste from a cherry cannory on tho shoro of Okanogan lake as a possible; sourco of pollution. This service was for the Dopartmont of Fishorios. No. 62 G.V. Wilby 3ho Fishos Colloctod bv tho "Vfa. J. Stewart" Expedition on tho Host Coast of Vancouver Island in 1934. Tho fishos collected by E.G. Hart in Ifay, June and July, 1934, were examined in the fall of 1935 and early in 1936. This work has been completed. Fishes were taken at 23 shore stations and 21 trawling stations. From the shore stations 357 specimens were taken and from the trawling stations 262, a total of 619 specimens.

Results: 1. Of the 66 species represented in tho total collections 38 woro from shore collections and 31 woro trawled at depths ranging from 3 to 70 fathoms. Only 3 species were found to bo in both shallow and doop wator. 2. Tnenty-throo families of fishos aro roprcsontod, 14 soinod and 14 trawlod with only 5 familios duplicated. 3. .Approximately 70$ of tho trawlod fishos woro of odiblo spocios. 4. Tho following four spocios, hithorto unrocordod from British Columbia wators wore takon: Sobe.stodos zacontrus, Ce.lycilopidotus spinosus, Liparis florao and Scytaline. cordalo.

G.V. wilby No* 63 Tho Lifo History of tho Lin?; Cod, Ophiodon olon^.tus Giraxd. In 1924 a study of tho lifo history of tho ling cod, Ophiodon olongatus, was stortod and carried on at such timos sinco as material for study could bo obtainod, and whon opportunities for obsorving tho fishos could bo had. Owing to tho dopths at which most of tho activities of tho ling cod aro carried on and tho rocky naturo of its habitat, obtaining matorial for this study has boen very difficult. Since spawning takes place at somo distance bolow tho lowest tides and in the winter months such observations as have been made are, of necessity, not as complete as mi^it be expected. Tfatil such time as adequate equipment can be devised for obtaining the young from the time of hatching until they have reached tho age of somo throe months there is nothing known of tho habits and habitat of thoso fish during tho months of Iferch, April and May. Until a dofinito tagging program can bo attempted the rato of growth cannot bo satisfactorily dotorminod as at tho prosont stago of tho study ago-dotormination from scalo readings has boon proven to bo impos sible, or at loast inconsistent.

Results;

A bullotin is now in tho hands of tho Editor doaling with tho history of tho ling cod, methods of tho fishery, catch statistics, oconomic valuo, otc. undor tho following hoadings: Methods of Ce.pturo; Fishing Season; Handling G.V. Wilby * Wo- 63 of tho Catch; otc. Tho lifo history has boon doalt with undor: Spawning; Egg Counts; Protection of Eggs; Incubation Poriod; Larval Stages; Maturity; Miximum Sizo; Food, otc. A summary of tho uses and by-products is includod* Undor "Consoration" recommondations havo boon mado rogr.rd.ing tho nocossity of protoc^^^ho mf^'tt^urmrt"'SD* incubation poriod as thoy aro rosponsiblo for tho success of a hatching of oggs, thoir e.bsonco rosulting in tho total loss of from somo 60,000 to half a million young fish in oach ogg-clustor.

jjP*t y^~