CONFIDENTIAL
FISHERIES RESEARCH BOARD OF CANADA
ARCTIC UNIT
Montreal, Que.
Annual Report and Investigatorsi Summaries
April l e 1959 to March 31, 1960
H. D. Fisher, In Charge CONFIDENTIAL
FISHERIES RESEARCH BOARD OF CANADA ,
ARCTIC UNIT
Montreal ) Que.
Annual Report and Investigators Summaries
April 1, 1959 to March 31, 1960 FISHERIES & OCEANS CANADA PECHES ET OCEANS CANADA LIBRARY / BIBLIOTFIEQUE 200 KENT, STATION 7244 OTTAWA, ON KlA OES H. D. Fisher, In Charge REPORT FOR 1959-1960 OF THE ARCTIC UNIT, MONTREAL, QUE. by H. D. Fisher, Scientist in Charge
The Arctic Unit carries out the responsibilities of the Fisheries Research Board toward marine and freshwater biological resources of the Yukon, Mackenzie, Keewatin and Franklin Territories, with the exception of Great Slave Lake which is covered by the Biological Station at London. Marine mammal studies are extended to the Atlantic coast of Canada. Fisheries potential is limited in the arctic, but stocks in general have been under-utilized, and there is room for small-scale development of fishing projects. Such development has begun in recent years with the current period of accelerated development of the north, and it is continuing on a gradually increasing scale. Field studies in fisheries aim at completing our knowledge of fish stocks throughout the vast region covered, and at providing a biological basis for management of subsistence, commercial and sports fishing activity. Similarly, studies on marine mammals, which traditionally have served as the backbone of native economy in most arctic marine areas, aim at following the effects of current utilization on the stocks, and at indicating where, to what extent and by what means further utilization can be accomplished without damaging the stocks. On the Atlantic coast, harp seals (Phoça g_r_oenlandiga) continue to 9 be exploited heavily by Canadian and Norwegian ships, on the spring breeding areas in the Gulf of St. Lawrence and off the east coast of Labrador and Newfoundland. Biological studies and population estimates have been carried out since 1949. The pilot whale (Globicephala Ep_lagna) is exploited for animal food in Newfoundland. Availability of this whale to the present hunting facilities varies greatly from year to year. A study of pilot whale populations and their relation to their main food, squid, aims at explaining and possibly forecasting fluctuations in pilot whale abundance off Newfoundland, as well as following the effects of exploi- tation on the stock. Studies on the distribution and abundance of marine invertebrates, including bottom fauna as well as plankton, contribute to our understanding of distribution and production, or lack of production, of fishes and marine mammals in given areas. Recent studies have concentrated in the area of eastern Hudson Bay and James Bay, a target for general economic development in the near future. These have been supplemented by fairly detailed oceanographic sampling and sections, in the relative absence of such work in this region to date. The Arctic Unit's headquarters consist of a stone house, converted from a residence, at 505 Pine Ave. West, Montreal. The premises are owned by and leased from McGill University, wnose libraries, together wlth those of _3_ the nearby Arctic Institute of North America, are open to the staff. In addition to the benefits of close contact with the University and other arctic work centred there, direct scheduled passenger and freight flights to the arctic leave from nearby Dorval airport, while much marine transport to the arctic leaves from Montreal harbour. The Unit operates no permanent field stations, although the need for one or two is becoming evident. The 50-foot wooden diesel ketch Calanus, built in 1948 9 handles many of the Unit's needs for marine mobility in the eastern arctic. From a wintering berth at Moose Factory, Ontario, the 1959 program of the vessel took it to various points in James Bay and southeast Hudson Bay, particularly around the Belcher Islands. The ship was sailed to Churchill for wintering and its engines were removed for overhaul. Construction of a 38-foot shallow-draft experi- mental fishing vessel, M.V. galvelingâ, was completed in Vancouver in 1959. The vessel was delivered to Tuktoyaktuk, N.W.T. in August by marine barge via Bering Strait, and was run to Aklavik, in the Mackenzie Delta, for over- wintering. The vessel has sleeping quarters for up to three, and is equipped with echo sounder, radio-telephone, dragging and gill-netting gear. It will conduct exploratory fishing in the western arctic. Fisheries Investizeiong SquIbeastern Hudson Bay. A fisheries party was based in Robertson Bay, Belcher Islands, during the summer, concentrating on the principal freshwater system of the • islands, Kasegalik Lake and River, and on a typical small lake and river tributary to Kasegalik River. Arctic char (e_Alzglinms. alp nup) was found to be the dominant species of economic value. Lake herring (LelmichIhyg arted),) were not taken in the Kasegalik system but were found in smaller lakes. Cod (âemp_ oe,ac) were common in the brackish mouth of the main river. Capelin (Mallotus vlllosps). and sand launce (Ammedytes sp.) were common food fishes of the above and other species. The char at the mouth of the river fed mainly on fish, including themselves, rather than on amphipods as in most areas of the arctic. Populations of both sea-run and land-locked char are présent in the lakes during the summers. There is evidence that sea-run char do not go to sea every year after maturing. Intermittent years of anadromy, where growth is reduced during summers spent in a lake, may explain a considerable variation in size for a given age of sea-run arctic char. Growth is slow, 16 years being required to produce the average maximum-sized fish. The Eskimo population of the Belcher Islands is largely dependent on animal resources for food. Organized fishing in this area therefore should be confined to produc- tion for local use. A small sports fishery is also possible. Frobisher Bay, Baffin Island. The commercial fishery for arctic char operated for a second consecutive year at the mouth of the Sylvia Grinnell River, accounting for about 22,000 pounds of a total weight of 47,500 pounds removed by commercial, subsistence and sports fishing. This total is somewhat higher than desirable if the size of individual fish is to remain at that desired by the commercial market. Experimental fishing conducted at the mouth of the Jordan River, some ten miles from the mouth of the Sylvia Grinnell, indicated a very low return of char per unit of effort and pointed to the insufficiency of this area as a commercial fishing site. DArien Grounds. Little to nothing has been known concerning the distribution and abundance of fishes in the barren grounds of Mackenzie and Keewatin Territories. During the summer, a fish survey was made of 20 lakes in the region east of a line between laMartre and Dismal Lakes, to the west coast of Hudson Bay. Four parties, of two and three men, each occupied five different lakes for periods of about 14 days. They conducted extensive fishing operations and were moved from location to location by an Otter aircraft. Special arrangements were made with the Royal Ontario Museum and the Institute of Fisheries at the University of British Columbia for the participation of their ichthyologists. The freshwater taxonomic collections brought out were deposited with these institutions. In addition to detailed informa- tion on the fishes, a variety of associated biological data and material were collected for other organizations and specialists. Whitefish (Corqunms. sp.) and lake trout (Sal4relinus namayoush) were the dominant species at all locations, followed by round whitefish (Prosopium nyliplzmpum), pike (Esox lucime), cisco (LeuciclIthys sp.) grayling (Thvmallus signifer) and burbot (Lea I,ota). Distribution of arctic char generally was limited to those waters draining directly into the sea though a few specimens were taken in Contwoyto and Kathawachaga lakes. Inconnu (Stenodus lgunlichthys) was completely absent from the lakes of the barren grounds. Pike were missing from the Back and Burnside River systems and north of these to the arctic coast. The lakes examined contained for the most part standing crops of large, old fish. A comparison of growth rates in the different water systems was made. White- fish from Vaillant Lake eg., (66°12 1 N, 11)+029 1W), which drains into Coronation Gulf via Tree River, require 30 per cent more time to grow to a maximum size than do those in Great Slave Lake, indicating lower productivity per area of water. Those from laMartre Lake, between Great Bear and Great Slave, on the other hand have a higher growth rate than do those of Great Slave Lake. Arctic char on the west coast of Hudson Bay show a higher growth rate than char from elsewhere on the barrens or from Frobisher Bay where production has been estimated at about four pounds per acre. Generally speaking, the highest fish production per given area of water in the region covered lay between Great Bear and Great Slave Lakes. Intermediate production is indicated across the northern sector (about latitude 670 M), less in the Dubawnt-Angikuni region and lowest in the southern sector (Clinton Colden, Whitefish, Wholdaia). Hazen Lakg421111gsmere Island. It was not possible during the Hazen Lake field work in 1958 to determine whether char ran to sea, via Ruggles River. Analysis of data in 1959 on the char collected however has shown the presence of both land-locked and sea-run populations in the lake. The sea- run char show the same large variability in size per given age as do those in other regions studied. Growth in Hazen Lake is approximately 30 per cent slower than in the Sylvia Grinnell system, Frobisher Bay. nojJales Island. Specimens of arctic char were obtained from an outside expedition to this area. Growth of these fish was shown to be almost identical with the growth of char from the Sylvia Grinnell system in Frobisher Bay.
Marine Mammal Investigations Walrus Population Studies. An aerial survey of walrus was carried out by Canso aircraft over the hauling- out sites at Coats and Bencas Islands, northern Hudson Bay. A slightly larger count than that obtained from vessel surveys in 1955 and 1956 indicates that the population in this area is maintaining itself. Age analysis of samples received from Grise Fjord (Ellesmere Island) and Igloolik in northern Foxe Basin shows a peak between 10 and 14 Yea'rs, few immature males, and a significant number of males over 20 years of age. The . latter fact suggests that this stock is not being heavily utilized. • The total annual kill of walrus in the eastern arctic is about 1,000, or 1,400 if we include Greenland. About 30 per cent must be added to represent the numbers lost . by sinking. Farbour Sea]Jopulation Studie . . In 1950 the bounty on harbour seals (Du= mitalm), which had been in effect fo/;, many years, was increase from $5 ,to $10 for seals other than pups of the year, in a attempt to reduce the population by taking more breeding adults. The kill ce older seals increased sharply for two years, then declined until by 1954 it reached a low level (about 250) which has been relatively constant to the present. Only half as many pups are taken now as in 1950. Age analysis of the 1959 catch shows a scarcity of older seals after maturity (4-6 years) 9 indicating a heavily exploited population. The total population appears to have declined by half since 19500 By contrast, age analysis of the bounty kill from Labrador and Newfoundland, which has been in effect for only -9- five years, indicates a population containing more older seals (up to 30+ years), and a low level of exploitation. Age and Growth of Grey Seals from Miramichi Bay. Age analysis of canine teeth from grey seals in this area of New Brunswick indicates a much faster growth rate for males than for females after the first year. The average maximum length for males is 94 inches, for females 81.5 inches. The natural longevity is in the high 30's. The age composition suggests a stable population» Food and Feedtm_d_Pilot Whalaa. Studies on the quantities of food in pilot whale stomachs orNewfoundland indicate that an average-sized pilot whale (length 13 feet) requires 20 to 30 pounds to fill its stomach. The greatest food intake was 6 0 pounds from the stomach of a 14-foot whale. Collections over a period of time indicate eight hours as the time taken for complete digestion. Total daily average consumption, when squid are abundant, is esti- mated to average 90 pounds per animal, almost all squid. The yearly consumption per animal, based on a main daily rate of 60 pounds per whale, is 21,900 pounds of squid and fish, probably mostly squid.
Biological Oceanography During the .summer operating season of the M.V. Calanus in southeastern Hudson Bay and James Bay, 72 stations were occupied, two of them several times. At these, 359 water temperatures and 6 5 bathythermograph drops -10- were recorded and >375 salinity, 376 oxygen, 120 phosphate, . 67 nitrate, 236 micro-plankton, 233 net plankton, 54 bénthos and 56 chlorophyll collections were made Eighty-four carbon-14 and 35 animal respiration experiments were done. Six hydrographie sections and a 'nuMber of sounding runs were made. Primary Production at the Belcher Islands. Chlorophyll, light- and dark-bottle oxygen and carbon-14 techniques were used for primary production estimates from two stations. The period of maximum production at the Belchers, though varying in different locations and years and dependent in large part upon time of, ice clearing, probably occurs generally between mid June and early July. Values are higher than those from more northern arctic locations, and slightly lower than those for full annual cycles in boreal coastal waters. HydroKraphic Observations in James Bay and Hudspu lam. Ice cleared from James Bay south of the Twin Islands
• about mid June in 1959. It remained heavy in the northern part until early July, and did not finally clear until well on in August. Almost 50 per cent of James Bay is less than 25 metres deep. Surface waters warmed quickly in the southern part, reaching more than 10°C by July 1. Minus temperatures, except on the surface where ice was present, occurred only at deeper stations. Oxygen fell gradually between June 21 and July 7 in the southern part. Consistently - 11- low phosphates in the southern part indicated a low produc- tive potential. A well-defined bottom ridge was found between the northeast Belcher Islands and Quebec. It separates the intermediate water into two distinct basins, with different characteristics. A brief visit to Richmond Gulf (August 9-11) indicated relatively warm surface water (17°C) and bottom water (a little less than 0°C at 120 m) in this region, compared to 6.5° at the surface and -1.2° at the bottom (130 m) immediately outside. A special report on the oceanographic data obtained in Hudson Bay and James Bay is being prepared. James Bay Zooplanktou. The standing crop of 2 zooplankton in James Bay is small (average 3.20 g/m )$ much lower than that of Hudson Bay. Daytime hauls of plankton indicate that the larger predominantly carnivorous forms (amphipods, medusae, large chaetognaths) are more numerous in the deeper, colder water, while the smaller, mainly herbivorous forms (copepods, cirripeds, larvaceans), which make up the greater proportion of the biomass, are more numerous in the upper layers where phytoplankton populations are found. Hudson Bay_ZoonMnktorl. The standing crop of zooplankton in Hudson Bay (average 8)45 g/m 2 ) was more than twice that found in James Bay. Highest values (32.05 g/m2 ) occurred north of the Belchers, and lowest 2 (2.48 g/m )among the Belchers and between them and Quebec. -12-
Foe BaUn_3oop1qnkIon, 1955z5b.. Analysis of collections made by the vessels Caianus and Lesadm. from Foxe Basin was completed. ..The average standing crop for ' all of this area was estimated at 2.58 g/m2 ,,less than James Bay. ZzlnlquktonUrom Ice IsUnd T-3. A collection made by T-3 personnel between July 10 and September 11, 1958, revealed a dominance of copepod nauplii. The most abundant species was CâUngs Imerbopeus. During the course cf the season the quantity declined significantly. The quantity was small and the species remarkably few. Phytoplanktop Studtu. Phytoplankton was sampled to supplement pigment and radioactive carbon data in the study of primary production. A definite succession of spring diatoms associated with ice (Pennatae) and summer diatoms (Centriceae), similar to that found in Foxe Basin in previous work, was revealed. It is evident that such successions will be found all over the arctic and subarctic. The higher temperatures (up to 10°C) and longer solar illumination than e.g., in Foxe Basin, in the Belchers was found to favour the development of some flagellated groups absent or rare in Foxe Basin. The number of Atlantic species is greater. Some species were found which had only been recorded in distant Pacific and warm seas. The sig- nificance of their presence in Hudson Bay is not clear. The value of studying living forms immediately on collection, -13- rather than after preservation which ruins many athecate forms, was demonstrated in that the number of .atheCate dineflagellates seen was almost as high as that reported for the Pacific Ocean, although only a few species have been recorded from previous preserved Hudson Bay Collections. STAFF AND ORGANIZATION (April 1, 1959 to March 31, 1960)
During this period 40 people have been on the Unitts staff: 7 scientific, 4 administrative, 9 technical, 20 seasonal and term. The total full-time staff as at March 31, 1960, numbered 15: 7 scientific, 3 administrative and 5 technical, with 1 technical position vacant.
List of Staff
Scientifiq H. D. Fisher, M.A., Ph.D. Principal Scientist, in charge J. G. Hunter, M.A. Senior Scientist E. H. Grainger, M.Sc., Ph.D. Associate Scientist A. W. Mansfield, M.A., Ph.D. Associate Scientist D. E. Sergeant, M.A., Ph.D. Associate Scientist A. S. Bursa, M.Sc. Assistant Scientist I. A. McLaren, M.Sc. Assistant Scientist (Educational leave to May 31, 1959 and from September 25, 1959) Administrative and Technical Lois G. McMullon Clerk 4 Jennifer S. Macdonald Stenographer 2 (to May 5, 1959) Gertrude I. McNulty Stenograther 1 Emmy K. A. Dreyer Stenographer 1 (from Oct. 19, 1959, term) I. G. Gidney Technician 1 (from Aug. 6, 1959) P. June Thompson, B.Sc. Technician 1 (to Oct. 30, 1959) T. E. Wilson, B.Sc. Technician 1 (to Aug. 7, 1959) Bert A. Arestad Assistant Technician 3 (to Sept. 15, 1959) Barbara M. Barry, 13.5e. Assistant Technician 3 (full- time from April 1, 1959) M, A. R. Day Assistant Technician 3 (from Dec. 16, 1959) Carroll M. Hutchinson, B.A. Assistant Technician 3 (from September 16, 1959) R. S. Szavay Assistant Technician 3 (to July 15, 1959) Baerbel A. vonNida Assistant Technician 1 2
seasonal ae Terni M. J. Dunbar, M.A., Ph.D. Associate Sdientist (May 1-Sept. 15, 1959) . W. F. Black, Ph.D. Assistant Scientist • (June 11 -Sept.. 14, 1959) G. Power, Ph.D.. ASsistant'Scientist, (June 15-Sept. 14, 1959) E. J. Crossman, Ph.D. Field Consultant. ..(June 15-July 18, 1959) C. C. Lindsey, Ph:D. • Field Consultant . (Jlily 12-August 20, 1959) J. D. Maehail, M.Sc. Field Consultant (July 26-Sept. 7, 1959) W. B. Scott, Ply.D. Field Consultant • (June 15-July 18 1 1959) . J. R. Bray Student Assistant (June 1-Sept. 18, 1959) P. J.>Ellickson Student Assistant (une 1-Sept. 14, 1959) S. S. Ferguson Student Assistant . (May 19-Sept. 8, 1959) P. H. JohanSen . Student Assistant (June 1-Sépt. 16, 1959) • J.1). McEachern Student Assistant " (June 1-Sept. 8, 1959) . A. E. Peden • Student Assistant (June 1-Sept..14,1959) D. Y. E. Perey, B.Sc. Student Assistant (June 8-Sept. 16, 1959) . G. G. Shaw Student Assistant (May 15-Sept.. 14, 1959) G. M. ,Telford . Student Assistant (June . 1-Sept. 1)-i- , 1959) T. K. Tom1inson ' Student Assistant . (June 1-Sept. 14, 1959) J.y. Berry Assistant Technician 2 (May 13-Oct. 19, 1959) J. Ann Holland Assistant Technician 3 . (from Nov. 9,1959, part-time) Sylvia M. Sutton, B. 8'0' Assistant Technidian 3 . (from Jan. 25 1 1960, part-time) Organization
juGliar ge Principal Scientist H. D. Fisher, Ph.D. A. Scientific and Investigational Staff Fisheries Senior Scientist J. G. Hunter, M.A. Assistant Scientist, seasonal W. F. Black, Ph.D. Assistant Scientist, seasonal G. Power, Ph.D. Field Consultant, seasonal E. J. Crossman, Ph.D. Field Consultant, seasonal C. C. Lindsey, Ph.D. Field Consultant, seasonal J. D. MacPhail, M.Sc. Field Consultant, seasonal W. B. Scott, Ph.D. Student Assistant, seasonal J. R. Bray Student Assistant, seasonal P. J. Ellickson Student Assistant, seasonal P. H. Johansen StUdent Assistant, seasonal J. D. McEachern Student Assistant, seasonal A. E. Peden Student Assistant, seasonal D. Y. E. Perey Student Assistant, seasonal G. G. Shaw Student Assistant, seasonal G. M. Telford Student Assistant, seasonal T. K. Tomlinson Marine Mammals Associate Scientist D. E. Sergeant, Ph.D. Associate Scientist A. W. Mansfield, Ph.D. Assistant Scientist I. A. McLaren, M.Sc. (Educational leave) Biological Oceanography Associate Scientist E. H. Grainger, Ph.D. Assistant Scientist A. S. Bursa, M.Sc. Associate Scientist, term M. J. Dunbar, Ph.D. Student Assistant, seasonal S. S. Ferguson B. Administration and Maintenance Staff Clerk 4 Lois G. McMullon Stenographer 2 Jennifer S. Macdonald (to May 5, 1959) Stenographer 1 Gertrude I. McNulty Stenographer 1 Emmy K. A. Dreyer (from Oct. 19, 1959, term) 2 C. Technical Services Technician 1 I. G. Gidney ("Salvelinus") (from Aug. 6, 1959) Technician 1 P. June Thompson, B.Sc. (General lab.) (to Oct. .30, 1959) Technician 1 T. E. Wilson, B.Sc. ("Calanus") (to Aug. 7, 1959) Assistant Technician 3. Bert A. Arnestad (Plankton, drafting) (to Sept. 15, 1959) Assistant Technician 3 Barbara M. Barry, B.Sc. (Library) (full-time.from Apr. 1, 1959) Assistant Technician 3 M. A. R. Day (General lab.) . (from Dec. 16, 1959) Assistant Technician 3 Carroll M. Hutchinson, B.A. (Plankton) (from Sept. 16, 1959) Assistant Technician 3 R. S. Szavay (General lab.) .(to July 15, 1959) Assistant Technician 1 Baerbel A. vonNida (Fish scales, otaliths) Assistant Technician 2, term J. W. Berry ("Calanus") • Assistant Technician 3, term J. Ann Holland , (Fisheries) Assistant Technician 3 term 1Sylvia M. Suttan,B.S. (Fish.scales) PUBLICATIONS (January 1 to December 31, 1959)
Anon. Arctic Unit of the Fisheries Research Board of Canada. The Polar Record, 9(63): 570-573. Bursa, A. S. The genus Prorocentrum Ehrenberg. Morpho- dynamics, protoplasmatic structures, and taxonomy. Can. J. Botany, 37, pp. 1-31. Ellis, D. V. The Benthos on Soft Sea-Bottom in Arctic North America. Nature, 184(4688): 79, 1959. Grainger, E. H. The Annual Oceanographic Cycle at Igloolik in the Canadian Arctic. I. The Zooplankton and Physical and Chemical Observations. HC alanusIt Series No. 20. J. Fish. Res. Bd. Canada, 16(4): 453-501. Grainger, E. H. and J. G. Hunter. Station List of the 1955-58 Field Investigations of the Arctic Unit of the Fisheries Research Board of Canada. "Calanus" Series No. 19. J. Fish. Res. Bd. Canada, 16(4): 403-420. Hunter, J. G. Survival and Production of Pink and Chum Salmon in a Coastal Stream. J. Fish. Res. Bd. Canada, 16(6): 835-886. MacPherson, A. H. and I. A. McLaren. Notes on the Birds of Southern Foxe Peninsula, Baffin Island, Northwest Territories. The Canadian Field- Naturalist, 73(2): 63-81, (April-June 1959). Mansfield, A. W. The Walrus in the Canadian Arctic. Arctic Unit Circular No. 2. Sergeant, D. E. Studies on the Sustainable Catch of Harp Seals in the Western North Atlantic. Arctic Unit Circular No. 4. Age Determination in Odontocete Whales from Dentinal Growth Layers. Norwegian Whaling Gazette, 6: 273-288, 1959. Evolution of Life Cycles in the Delphinidae (Cetacea). Preprints International Oceanographic Congress, 31 August-12 September, 1959. Section: Populagons of the Sea (Physiology and Behaviour of Marine Organisms): 184-1850 Sergeant, D. E. and D. H. Pimlott. Age Determination in Moose from Sectioned Incisor Teeth. J. Wildlife Manag. 23(3): 315-321. MANUSCRIPT REPORTS
Dunbar, M. J. Field data for 1949-1954. "Physical Oceanographic results of the Calanus expeditions in Ungava Bay, Frobisher Bay, Cumberland Sound, Hudson Strait and Northern Hudson Bay, 19+9- 1955". Journal of the Fisherïes Research Board of Canada, 15(2): 155-201. Fish. fies. Bd. Canada MS Rep. Series (Oceanographic and Limnological) No. 56, 1959.
MANUSCRIPTS SUBMITTED FOR PUBLICATION
Bursa, A. S. Ectoplasm as a morphogenetic factor of membrane structure in dinoflagellates: completed observations on Wolommal[iiâ limnetica. Svenska Botanisk Tidskrift. Mansfield, A. W. Walrus. Arctic' Unit Circular No. 3. In Press. Mansfield, A. W. and IL D. Fisher. Age Determination in the Harbour Seal, Phoca vitulina L. Nature. McLaren, I. A. Methods of estimating numbers and availability of ringed seals in the eastern Canadian Arctic. Polar Record. Population dynamics and the exploitation of seals in the eastern Canadian Arctic. Ecological Symposia, British Ecological Society.
MANUSCRIPTS SUBMITTED FOR PUBLICATION Previously Reported
McLaren, I. A. On the Origin of the Caspian and Baikal Seals and the Paleoclimatological Implication. Amer. J. Science. INDEX TO SUMMARY REPORTS
APPENDIX Number Page Great Whale River 1 2
Belcher Islands 2 3 Frobisher Bay 3 7 Jordan River Char Fishery 4 10
Survey of Fish in Barren Ground Lakes 5 11 Hazen Lake 6 18 Prince of Wales Island 7 21 Walrus Population Studies 8 23
Harbour Seal Population Studies 9 27 Age and Growth of Grey Seals from Miramichi Bay 10 30 Squid and Pilot Whale Catches 11 31 Food and Feeding of Pilot Whales 12 35 Primary Production at the Belcher Islands 13 39 Hydrographie Observations in James Bay and Hudson Bay 14 41 James Bay Zooplankton 15 44 Hudson Bay Zooplankton 16 47 Rowley Island Zooplankton e 1957 17 48 Foxe Basin Zooplankton e 1955-56 18 50 Zooplankton from Ice Island T-3 19 51 Phytoplankton Studies 20 52 Fisheries Investigations
The fisheries studies in the Arctic for 1959 included surveys on the fish of: 1. Great Whale River 2. Belcher Islands 3. Frobisher Bay (a) Sylvia Grinnell system (h) Jordan River system 4. Barren Grounds east of Great Slave-Great Bear Lake 5. Hazen Lake 6. Prince of Wales Island Emphasis was placed upon char studies at the first three mentioned locations while all species were considered in the lakes of the Barren Grounds. Six field parties consisting of personnel from eight Canadian universities carried out the field studies. Personnel assistance from the Institute of Fisheries at the University of British Columbia and the Royal Ontario Museum in Toronto was greatly appreciated. Fish specimen collections have been deposited with the above two museums while special collections other than fish have and are being sent to other interested institutions and individuals. Otoliths have been read and ages assigned to Arctic char caught in 1958 at Hazen Lake on Ellesmere Island and from Young Lake and Browne Bay on Prince of Wales Island. -2-
No. - 1 Great Whale River The trip into the Belcher Islands was delayed at Great Whale River for ,a short time while landing con- ditions.= Kasegalik Lake improved. Advantage was taken of this delay to examine the. fish in the mouth of the Great Whale River. Gill net catches produced five species Of fish, identified as arctic char (Palmellnuz alminge), northern pike (Luz luaus.), lake herring (Imuich/jama sp.), northern sucker (Qâtes_teMIU catostomu) and sculpins (Cottidae). The fish stocks in this river are utilized by the local natives to some extent but it was gathered that fishing effort may vary considerably from year to year depending upon the catches of seal and occasional white whales. Éxamination of native nets near the mouth of the river indicated their effort was concentrated on. the lake herring since only small-mesh nets were in evidence... Age and growth analysis are yet tobe made upon the fish from ' Great Whale River but age and growth rates - determined upon char and lake herring from other Arctic locations show a. faster rate of growth and earlier maturity for lake herring than for char.. Arctic,char exposed to the small-meshed nets are likewise caught but at a size much below their potential size limit so that the productive capacity of this species is usually reduced to some fraction of.its -3- real potential. Some larger char always escape the small- meshed nets but the productive capacity of the species as a whole is much reduced. Total annual production from such fisheries is usually greater when optimum size-mesh nets are used to concentrate on the lake herring population.
J. G. Hunter and D. Y. E. Perey
No. 2 Belchgr Islands Kasegalik Lake is thé làrgest lake on the Belcher Islands and is separated from the sea for the greater part of its circumference by a harrow one-quarter-to three-mile- wide land border. Many smaller lakes are present on the Belcher Islands, some adjacent and tributary. to the Kasegalik system, others draining to the sea separately. Kasegalik Lake and River and a tributary system Kapasilik Lake were the main area of study. All species of fish taken on the Belcher Islands are of a euryhaline character indicating repopulation has been by way of the sea. Arctic char (Salvelinus alpinus) was the dominant species by weight while the little nine- spined stickleback (Enuitimn Dungiumq) probably exceeded the char in numbers. Lake herring (Leucichthm artedl,) were reported present in many of the small lakes of the Belchers and were taken only in such lakes during the survey. Only one specimen of brook trout (Salvelinus fonttnels) was ' caught. Cod (0adu °Rae) and sculpins (Mywçocephalus ouadrturnls) were frequently caught in the mouth of the river where brackish water prevailed, while capelin (Melotus vi,11qsas.) and sand launce (Ammodvtes sp.) were found in stomach contents of other species caught in the same area. The feeding of char, based upon stomach examina- tions, differed from most areas previously investigated in that very few amphipods were being eaten. Food consisted principally of fish, cannibalism being common. Sticklebacks were frequently found to be consumed in large numbers. It was observed that the smaller Arctic char consumed relatively greater weights of food than did the larger char and:that less food was consumed by char of all sizes at the end than at the beginning of the summer. Populations of both "land locked" and anadromous Arctic char are present in the lakes of the Belcher Islands during the summer: The presence of the two stocks is evident from size, age and growth analysis, as well as from individual mature specimens.of small size. The smallest mature female caught measured 9.0 cm and weighed 7.9 g. In a small stream and lake system (Kapasilik Lake) tributary to the mouth of the Kasegalik River a mixed popula- tion of "land-locked" and sea-run Arctic char was examined. The Kapasilik outlet stream was so small that large char are unable to navigate it except during the high spring runoff and the high spring and neap tides. Many of the large sea-run" type char found in the lake were preparing to spawn but over 50% showed no indication of maturing in the present year. In this system large char, though not preparing to spawn in the present year are "land locked" by physical barriers for definite periods of time. Other lakes in other regions where no physical barriers exist show a portion of the "sea-run" population to be present in the lake during the summer, which indicates that char do not go to sea every year after initiation of the migratory habit. Size for any given age, beyond a length of 40 cm, shows considerable variation between individual Arctic char. This variation in size for a given age can readily be explained by intermittent years of anadromy where growth may be considerably reduced during summers of lake tenure. The growth rate for Arctic char of Kasegalik Lake (Figure 1) shows that 16 years are required to produce the average maximum sized fish. The slow growth rate evidenced indicates relatively low production. A population of harbour seals resident in the lake possibly play a role in limiting the numbers of char through predation of the larger individuals. The Eskimos of the Belcher Islands are largely dependent upon the animal resources of the islands for food. The low production of fish in this area precludes organized fishing where the product may be destined for other areas. Latitude for increased catch by local Eskimos and a small 2
, 9.■
C . Clà -J Figure 1. Growth of arctic char in 'Kasegalik- Lake - Belcher Ulands.
g e in Years sports fishery are possible without affecting production levels or return per unit of effort seriously. Lake herring contribute to the food supply but are minôr in importance in comparison with the Arctic char.
J. G. Hunter and D. Y. E. Perey
No. 3 Fyobisher Bay (1)29.MUUrflLIZh2.u. The commercial fishery for Arctic char in Frobisher Bay continued its operation for the second consecutive year. The total catch of char was taken in a two-week period. Statistics of the catch are shown in Table I. (2)Sports Fisherz. Delayed ice conditions hampered the sports fishery this year so that ostensibly it did not commence until July 10. Fraquent wet and cold days dissuaded all but the ardent fishermen while at the same time fewer sports fishermen, according to the number of licences sold, were present in Frobisher Bay. The total hours spent sport fishing were reduced by 35% while the total sports catch, assessed at 1,476 fish, was a reduction of 49% over the preceding year. In lieu of a more accurate average weight of these line-caught char the average weight of five pounds has been employed to provide the estimate of 7,380 pounds for the total sport fishery catch. (3) Eskimo Fishery. The Eskimo fishery is very difficult
Table I. Daily catch of Arctic char and units of effort used in 1959 Frobisher Bay commercial fishery.
Weight Dat.Q. EDAL_PS ginh (Round) Daitl_e_efgrI Ju1y 16 . ' 74 441 . 3 . 17 . 478 ' 2,825 . lo 18 454 3,277 lo ' 20 120 844 3 21 340. 2,084 10 22 372 2,186 13 23 45o 2 , 602 13 24 241 1,502 • 7 25 242 1,530 . 7 26 164 931 . 6 27 . ' 345 2,122 lo . .28 . 28 216 ' ' 3 29 . 199 1,053 ' 7
Total 3,507 . 21,613 102 Average weight of fish = 6.16 pounds Catch/Unit of effort* = 34.4 Arctic.char
* Unit of effort = One 4i in mesh 50 yard nylon gill net l fiShing for one tidal cycle (12 hours) • -9-
to assess in that fishing methods were diversified and fishing locations were scattered. The estimate of total catch, based upon interrogation of the natives themselves and supplemented with observations by two observers, is 3,300 char. These fish are probably smaller than those taken in the commercial fishery since smaller mesh nets were frequently used. Anglinge spearing and jigging account for about 25% of the catch. No accurate figure of weight for the total catch is possible but in view of the gear used the average weight of fish caught by the Eskimo fishery is likely to be less than that of the commercial fishery. If an average weight of 5.0 pounds is assumed an approxi- mation of the total catch is 16,500 pounds. This is 25% higher than the Eskimo catch of the previous year. (4)Experimental Fisherylujevia_Grinnell Lake. Fishing was conducted in Sylvia Grinnell Lake in the latter part of August and early September. The catch included both nsea-runn and "land locked" populations. A total of 1,050 pounds of• fish were removed from Sylvia Grinnell Lake with the "land locked" forms accounting for roughly 15% by weight. (5)Experimeniâi_Elshery_inFrobialer_My. A small catch of fish was made in the mouth of the Sylvia Grinnell River in order to provide samples and specimens. This fishery took a total of 191 fish weighing about 1,000 pounds° (6)Summary of Caches from Sylvia Grinnell System. The total weight of Arctic char removed from the Sylvia Grinnell -10-
system is the sum of the weights of all the fisheries which resulted in a total catch of 47,500 pounds. Con- tributing to the stock of fish being exploited, apart from annual recruitment and growth, is a portion of the accumu- lated reserve stock from years when the fishing was less intense. The 1959 total catch is near maximum production for the area if considered on the basis of maximum suàtained • yield. Continued high exploitation is not recommended if •the present fishing economy of the three operating fisheries is to be maintained.
J. G. Hùnter and J. R. Bray
No. 4
•JexAâaLlamg_nhu_Eigherv • The commercial fishery run by the Department of Northern Affairs had hoped to make use of the Arctic char stocks of the Jordan River, a small àtream adjacent to, and • running inland parallel to-the Sylvia Grinnell River. . Experimental fishing was conducted in the waters offshore from this stream during early August. Samples for age analysis were taken to compare growth rates of char in this system with those of the Sylvia Grinnell. This analysis has not been made though it is not expected that any signifi- cant difference will exist in growth rates of the two stocks.
. . The Jordan River is a small stream (flow less -than 20 cubic feet per second) which drains into Frobisher Bay - 1 1--
over an extensive tidal flat. The mouth of the river is approximately 10 unprotected sea miles away from the Frobisher Bay settlement. The small size of the Jordan River precludes a large population of fish. Its drainage over an extensive tidal flat makes netting extremely arduous while the long open stretch of water that must be navigated at short time intervals to insure a high quality catch all contribute to the insufficiency of the area as a potential commercial fishing area.
During a five-day fishing period, 220 char were caught resulting in the low return of only seven fish per unit of effort.
J. G. Hunter and J. R. Bray
No. 5
rvey_of Fish In Barren Ground Lakes The distribution and abundance of the different species of fish in the mainland section of the Northwest Territories have been largely Unknown quantities until quite recently. During the summer of 1959 the Arctic Unit started on the task of collecting information by conducting a survey on 20 lakes (Table 11) throughout the region east of a line from Lake la Martre to Dismal Lake. The survey party was made up of four three-man teams equipped for camping and conducting fairly extensive -12-
Table II. Lakes of .Northwest Territories covered by risherieS: survey in 1959.
Lajce â4r th Latitude .West Lqngitule La Martre 63° 10 1 . 117° 43' Beaverlodge 0 381 64 118° 08' Redrock 650 29 1 114° 24' Dismal 1 67° 13 116° 32' Vaillant 12' 66° 114° '29' Kathawachaga 66° 15' • 111° 08 1 Clinton Colden 63° 50i ° 38' 107. Whitefish 620 36 1 1060 43 1 Who ldaia 0 45 1 60 0 30' 104 Ellice 65° 1+3' • 106 0 00 1 Beechy 12' 650 106° 28' Macdougall 650 59' 98° 34 1 Beverly 64° 35' 100° 38' Dubawnt 620 43' 102° 31 1 Angikuni 62° 17' 99° 36' Hyde 600 451 950 211 Maguse 610 24 1 940 241 Meliadine 63° 02 1 920 231 . Maze 0 23' 62 930 251 Armit 640 06 1 910 321 -13- fishing operations. Each team occupied five different lakes for periods of about 14 days during the course of the summer. Parties were efficiently moved from location to location by one of Wardairts Otter aircraft. Fishing gear consisted of a variety of nets including nylon gill nets, monofilament gill nets, beach seines, hand seines, rotenone and rod-and-line. The nylon gill nets were the basic and main equipment used for cap- turing fish. Each team was supplied with two gangs of nets of mesh sizes 1-1, 2*, 3-b e 4i and 5i inches, totalling 500 yards of net per team. The catching efficiency' of these nets was probably reduced in comparison with standard commercial nets since heavier twine sizes were used. However, the resulting nets were stronger and, by lasting throughout the season, maintained the same efficiency from lake to lake. Various samples and measurements were taken from the fish for outlining the biology and production of the different species encountered. Specimen collections for taxonomie studies have been deposited in the Royal Ontario Museum and the fisileries museum at the University of British Columbia. Generally most of the lakes examined were relatively shallow with depths averaging about 50 feet. A few deeper lakes were observed to have depths exceeding 125 feet. Temperature profiles showed summer warming of the lakes with stratification occurring in most of them. None of the lakes examined could be called polar lakes in view of their relatively warm summer surface temperatures. The species of fish found throughout the entire area remained much the same. Some warmer water forms which have penetrated as far north as Great Slave Lake and parts of the Mackenzie River were absent in the lakes of the Barren Grounds. Range limitations for some of the larger food fishes were observed. Inconnu (Stenodus leucichthys), in Great Slave Lake and the. though relatively plentiful Mackenzie River, were completely absent from the lakes of the Barren Grounds. Broad whitefish (CoreRonus asus), so common in the lower reaches of the Mackenzie and Coppermine Rivers, were generally restricted to coastal regions in the western sector of the area. Common whitefish (PL. cluDeaformis) White suckers (Catostomus were found almost everywhere. commersonl.) were confined to the southern sector of the Territories. Arc.tic char (Salvelinus alpinus) were generally restricted to coastal watersheds, though a few specimens were taken as far South as Contwoyto and Kathawachaga Lakes. A substantial Eskimo fishery exists for Arctic char at the mouth of the Coppermine River but in three lakes of this system examined, none were found. In view of the reports of catches made in the river well inland it may be that the char confines itself to the river proper and does not utilize -15-
the tributary lakes and headwaters. Pike (Es gz lugim) showed an erratic distribution being present in some lakes and absent from others in the same drainage system. Pike were completely missing from the Back-Burnside River systems and the area North of these rivers to the coast. Other major species such as lake trout (Salvelinus namaycus0, grayling (Thymallus ziEnifer), round whitefish (Prosopium Dylindracemm), lake herring (Leucichthvs sp.) and burbot (Lote, ,lota) were present in almost all areas. ' The lakes examined contained either untouched or only slightly utilized stocks of fish, which suggested that fish of great age and large size would be found. This was indeed the case, since numerous lake trout over 30 pounds in weight were caught and ages of the larger fish of all the species examined were relatively great. Data on age and length, combined to give growth rates, provide a comparative index of production from lake to lake. In Tables III and IV increase of size with age for whitefish (2,.. nlugaformis) and Arctic char in some lakes of the Barren Grounds is shown. The high ages of these fish are readily apparent. The sizes of the fish at various ages show a slow rate of growth which in turn reflects a low rate of production in these waters. The present state of analysis does not merit
- 16 -
Table III. Increase of Average Length. With Age of Common Whitefish (emmlonua clupeaformia) in Lakes.of Northwest Territoriea.
Fork Length (in cm) Aga Great Slave Tqa Martu Vai1lant Ellice Beverly Pyde 1 2 10.2 13.2 Z. 26.7 14.6 17.3 16.8 5 24.5 16.6 23.6 17.0 26.9 6 18.4 26.8 18.1 26.1 7 19.8 32.1 22.0 29.0 8 . 35.6 41.7 21.6 . 36.3 30.0 28.0 9 44.1 ' 24.4 39.6 10 41.9 45.4 30.9 42.5, 37.6 - 11 50.7 31 ..3 45.6 , 37.4 43.8 12 45.7 52.0 32.4 48.3 38:3 44.2 13 . 53.4 35.2 51.4 38.9 45.0 14 50.8 53.8 38.4 54.3 40.9 45.2 15 54.4 42.7 56.2 ' 43.0. 45.8 .16 53.3 55.1 47.0 58.3 43.3 46.3 , . 56.1 49.2 . 59.8 43.8 46.8 d 56.5 50.3 60.3 44.9 48.0 19 59.2 50.0 61.3 45.8 48.6 20 57.1 50.8 60.7 46.4 49.9 21 58.1 52.0 61.1 47.9 51.0 22 51.3 59.2 . 47.8 49.8 51.8 60.2 49.8 51- 3+ . -53.6 , 49.4 25 ' 50.5 50.8 26 51.0 . 27 53.1 (1) .- ' (2) Total No. samples 1,174 453 5 422: 621
• (1) figures taken from Rawson, D. S. North West Canadian Fisheries Surveys in 1944-45, Bulletin Fisheries Research Board of Canada, No. 72, 1947. (2) length at intermediate ages determined from back calculation. The extremely small sample limits usefulness of these figures.
-17-
Table IV. Increase of Average Length With Age of Arctic Char (Oalveltgm alpinus) in Lakes of the Northwest Territories. Fork Length (in cm) Sylvia Grinnell Coppermine Age (Frobisher Bay) (Riser/ Kplhawachaga 114cdougall Maze Maggsp 1 2 7.6 Z 8.9 5 10.9 10.0 6 14.6 17.7 7 17.5 41.5 52.3 8 24.9 45.9 54.8 9 27.8 50.7 64.7 6 0 . 0 lo 34.7 59.7 42,0 41.4 60 .2 62.8 11 38.8 61.2 42.5 73.7 65.6 12 43.7 64.o 41.9 51.5 56.2 67.7 13 48.6 69.9 46.6 70.6 67.4 14 53.3 72.3 48.0 55.8 66.7 73.3 15 56.5 71.4 51.0 63.2 72.8 77.5 16 59.5 76. 0 )+6.6 59.5 66.4 73.3 17 63.3 81.4 53.9 74.6 18 65.9 70.4 80.2 19 65.2 71.7 20 68.6 73.0 83.7 21 66.4 51.2 71.7 22 66.4 65.8 23 67.5 24 65. 0 75.9 25 68.0 26 68.2 27 67.0 28 69.0 29 68.0 30 65.0 ) ) ) 33 66.0
Total sample 2,671 402 18 39 44 270 calculation of the comparative productiyitles of the lakes . in weight of fish per unit of lake surface but an approxi- mation can be made from . comparison of growth rates of the same species in different systems. The whitefish in . Valliant, Lake require 30% more time to grow to the same . average maximum size as the whitefish in Great Slave Lake, indicating a lower comparative productivity. On the other hand whitefish from Lake la Martre have a higher grOwth rate and show a greater productive potential than do those Of Great Slave Lake. Similarly Arctic char taken from the west coast of Hudson Bay show an increased growth rate and therefore greater productive potential than char from elsewhere in the Barren Grounds or from Frobisher Bay where. production has béen. evaluated at about- four pounds per acre.
J. G. Hunter
No. 6 Jiazen Lake In the summer of 1958, Mr. I. A. McLaren conducted biological studies in Hazen Lake on Northern Ellesmere Island. His studies included extensive examination and collection of samples from the single-species fish populations present in the lake. All told 537 Arctic char (Salvelinus alpinus) were taken for subsequent age and growth analysis. -19-
The Ruggles River drains from the east end of Hazen Lake to the sea and has only minor falls and rapids which do not form major obstacles to migrating fish. It is not definitely known but it may be reasonable to suppose that ice conditions in the area may, in some years, block or increase the difficulties of summer migrations. At any rate Hazen Lake, from age and growth analysis, show two populations of Arctic char to be present and that the"sea- rudpopulation shows a large variability in length for ages after the fish have changed from the lacustrine to migratory habit. This large variability might be expected since the anadromous forms do not necessarily migrate every year. The poorer feeding conditions of the lake habitat can readily account for observed differences in size of equal- aged fish. The growth of the two populations of Arctic char in Hazen Lake are compared in Figure 2 with the growth of It sea-run" char from the Sylvia Grinnell River in Frobisher Bay. The above figure readily shows the difference in growth rate between the three populations of Arctic charo Approximately a 30% longer period of time is required to produce the same size of "sea-run" fish in the two systems.
J. G. Hunter. 70-0 Sylvia Grinnell (Sea Run)•
60-0
Hazen Lake
( Sea Run 50-0
40-0
Hazen La ke -C 30.0 Cr) ( Land Locked ) cu
20-0 Figure 2. Growth of *land-locked" and anadromous, arctic char from Hazen Lake and Sylvia Grinnell River. 10-0
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 .34 g j I 11 ,I i i i s t t I I
Age in Years -21-
No. 7
Prtra Of Weeq_Illdad In the summer of 1958 Mr. T. H. Manning and Mr. and Mrs. A. Macpherson, while conducting a study on Prince of Wales Island, took, incidental to their main • work, length measurements and otolith samples from the Arctic char which had been caught for food purposes. A total of 115 specimens were caught in Young Lake and River and the southern end of Browne Bay of Northern Prince of Wales Island. ,The otoliths from these fish have been read for age and are.shown with their lengtn in the form of a growth curve in Figure 3. The sample of fish taken is small and selected for a certain size range, since only enough suitably- sized fish were caught to supply food needs. The samples takenl however, indicate the growth of these fish to be almost identical with the growth of char from the Sylvia Grinnell River in Frobisher Bay.
J. G. Hunter - 70-0
6 00
50- 0
400
I- 300 cl) _J 200 Figure 3. Growth of arctic char from Prince of Wales Island.
100
4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34
Age in Y ears -2 3-
Marine Mammal Investigations No. 8 Walrus Pumlation Studies From 11-13 August an aerial survey of white whales and walrus was carried out from Churchill using a Canso of TransAir Ltd. • After surveying the. major river mouths known to be frequented by white whales in the area north to Rankin Inlet, the aircraft flew across to the hauling-out sites of walrus at Coats Island. Low cloud prevented a complete check of all the sites at Bencas and Coats Islands but 650 walrus were counted. More extensive frontal cloud lay across Seahorse Point, Southampton Island, and no further observations could be carried out on that day (12 August). On 13 August the aircraft left Coral Harbour and flew north to White Island e Frozen Strait, Vansittart Island and the Sturges Islands. Most of the area was covered with heavy pack ice and no walrus were seen. The aircraft returned to Seahorse Point on southeastern Southamp- ton Island, but the previous day's frontal cloud still lay heavily over the area and no observations were possible. Coats and Bencas Islands were rechecked on the return journey to Churchill, and this time approximately 750 walrus were seen. Though the walrus counts were incomplete, the numbers seen about Coats and Bencas Islands were slightly -24- larger than those recorded in 1955 and 1956 from small boat surveys. The population in this area therefore appears to be maintaining itself. (B)S amples of jaws were received from Grise Fjord and Igloolik and the teeth were sectioned for age analysis. The age frequency distribution of the Igloolik sample (all male) is shown in Figure 4 and is similar to the combined 1956 to 1958 sample shown in the 1958 Annual Report. Once again, there is a peak between 10 and 14 years, with few immature males present, and also a signifi- cant number of older males over 20 years. The latter fact would suggest that this stock is not being heavily utilized. (C) The total annual kill of walrus in the eastern Canadian Arctic and west Greenland is shown in Figure 5. The data for Canada were mostly obtained from the annual game reports of the Royal Canadian Mounted Police and letters from post managers of the Hudson's Bay Company; information from Greenland was supplied by Dr. Poul Hansen, director of Grenlands Fiskeriundersdgelser. The records are from 1948 onwards, the range in years being indicated in the figure. The annual total kill for the eastern arctic, averaged over these years is about 1,000, or 1,400, if we include Greenland. To this must be added another 30% to represent the approximate numbers lost by sinking. This loss is high, but does not compare with the losses incurred in the Bering Sea which are estimated 1959
5 -a 4 3 es 2 o d I I 1 2 3 4 5 6 7 8 9 10 H 12 13 14 15 16 17 18 19 20 20+ 25+ 30+ Age in years
Figure 4. Age composition of walrus kill, Igloolik, N.W.T., 1959. -26-
4e-5e
49-84
52-5,8,9
25 - NUMber of walrus token
For each encircling ring Increase number by 100
Arrow points to hunting
locality
Figure 5. Distribution of annual walrus kill in Canada and west Greenland. -27- as equal to the number of walrus taken.
A. W. Mansfield
No. 9 Harbour Seal Population_Dtudies (A) Maritime Provinces. The bounty system has been in effect for many years and by 1949 was rewarding hunters with $5 per seal taken. In 1950 the bounty on seals other than pups of the year was increased to $10 in an attempt to reduce the population by taking more breeding adults. The success of this measure is indicated in Figure 6, which shows the total catches of pups and older seals from 1950 onwards. In 1951 and 1952, the catch of older seals increased sharply, but by 1954 the annual take had dropped down to a level of 250, which has been maintained with minor variations until the present day. The effect on the number of pups taken has been marked, and in 1959 only half as many were taken as in 1950, which suggests that the total catch may now have levelled off. Since there is no reason for believing that there has been any change in hunting intensity, or in the habits of the pups themselves, it is probably safe to conclude that the total population has also declined by half.
An age analysis of the larger part of the 1959 catch is shown in Figure 7a. The comparative lack of older -.28 –
1200 111111 —Pups 1100 —Older Seals 1000
900
800
700
600
500
400
• 300
200
100
51 52 53 54 55 56 57 58 59 YEAR %Older Seals 16 24 30 26 26 25 28 30 35 26
Figure 6. Bounty kill of harbour seal pups and older 'seals from 1950 onwards. -2 9-
Mar itime Provinces
470 N.) Figure 7a. Age composition of harbour seal bounty kill in Maritime Provinces, 1959.
20 1.1.0■11,
10.1
0