Showing papers in "Wsq: Women's Studies Quarterly in 1953"
168 citations
TL;DR: The Arctic char was studied, in the summers of 1948, 1950 and 1951, about the mouth of the Sylvia Grinnell River, Frobisher Bay, Baffin Island, and otoliths are shown to be reliable age indicators and are used for age determination.
Abstract: The Arctic char (Salvelinus alpinus Linn.) was studied, in the summers of 1948, 1950 and 1951, about the mouth of the Sylvia Grinnell River, Frobisher Bay, Baffin Island.Otoliths are shown to be re...
103 citations
TL;DR: In pink salmon (Oncorhynchus gorbuscha) the survival during the freshwater phases of the life-cycle has been found to vary from about 1 to 24 per cent of available eggs.
Abstract: In pink salmon (Oncorhynchus gorbuscha) the survival during the freshwater phases of the life-cycle has been found to vary from about 1 to 24 per cent of available eggs. Natural survival during mar...
94 citations
TL;DR: To determine natural annual growth, lobsters of 15 to 25 cm.
Abstract: Carapace measurements of lobster larvae caught in the western part of Northumberland Strait showed that in this area the natural growth in length per moult is 34.4 per cent from stage 1 to stage 2, 31.8 per cent from stage 2 to 3, and 30.3 per cent from stage 3 to 4. The seasonal distribution of the first four larval stages was determined from plankton tows made continuously from mid-June to late September each year from 1948 to 1952. To determine natural annual growth, lobsters of 15 to 25 cm., total length, were sorted into five or six size groups and were distinctively marked by means of holes punched through the tail fan. These were liberated on six widely separated fishing grounds in the Maritime Provinces. Recoveries of these marked lobsters four to twelve months after release showed that in the southern Gulf of St. Lawrence, 15- to 20-cm. lobsters grew 8 to 9 mm. (13 to 15 per cent) in carapace length, 22 to 25 mm. (13 to 14 per cent) in total length and 80 to 95 grams (45 to 53 per cent) in weight...
81 citations
TL;DR: There was, for these animals, a seasonal change of the selected temperature which was distinct from the changes in selec...
Abstract: The selected temperature of two- to three-inch trout (Salvelinus fontinalis, Mitchill) was determined in a horizontal gradient a number of times during the months of November, December, January, Fe...
73 citations
TL;DR: During the summers of 1950 and 1951 the upper lethal temperature was measured for 14 species of freshwater fishes, representing five families, and the experiments were conducted in the Summerland Trout Hatchery.
Abstract: During the summers of 1950 and 1951 the upper lethal temperature was measured for 14 species of freshwater fishes, representing five families. The fish were captured from lakes in the southern Okan...
69 citations
TL;DR: Bullheads and three speckled trout kept in complete starvation and examined for the presence of bacteria in the intestine did not yield bacteria, and a Pseudomonad was obtained from the intestine of one bullhead.
Abstract: Sixteen bullheads (Ameiurus nebulosus) and three speckled trout (Salvelinus fontinalis) were kept in complete starvation for periods of time varying from one to two months and seven to ten days res...
58 citations
TL;DR: The seasonal cycle of phytoplankton pulses which occurs in many parts of North America is outlined and evidence that this cycle is caused chiefly by the seasonal change in water temperatures resulting from the change in solar radiation is presented.
Abstract: In reviewing the literature dealing with the influence of physical, chemical and biochemical factors on the development and decline of phytoplankton pulses, this paper first outlines the seasonal c...
54 citations
TL;DR: The bottom fauna of Great Slave Lake is typical oligotrophic, dominated by the amphipod Pontoporeia affinis and including several species of sphaeriids (Pisidium), oligochaete worms and chironomid larvae (mostly Spaniotoma), which resembles those of Lakes Athabaska, Reindeer, Winnipeg and Michigan.
Abstract: THE macroscopic bottom organisms of Great Slave Lake were sampled with more than 600 dredgings in the summers of 1944 to 1947. Additional ecological information was obtained from qualitative collec...
46 citations
TL;DR: The total annual mortality rate of 61 per cent represents the unexploited condition and a moderate mortality rate acting at all ages will easily account for thousands of eggs being produced for every whitefish that survives to maturity.
Abstract: Ages were determined of 6,571 whitefish for which sizes were recorded. A length-weight relationship, the percentage of both sexes mature at each age, the sex ratio, the proportion of mature females that spawn annually and the relationship between size of fish and number of eggs were determined from smaller samples.Growth rate is difficult to assess because of net selection, but it seems to be slower than in more southerly lakes. Growth appears to be limited to the period June to September inclusive.The total annual mortality rate of 61 per cent represents the unexploited condition—four years of commercial fishing with 51/2-inch mesh gill-nets produced no obvious change. A moderate mortality rate acting at all ages will easily account for thousands of eggs being produced for every whitefish that survives to maturity—it is unnecessary to assume a low percentage of eggs fertilized or excessive mortality among fertilized eggs or among young fish.A more intensive fishery would probably increase sustained yield.
39 citations
TL;DR: In this paper, the chemical composition of plankton, of sediment collected at the 11-meter level, and of surface bottom sediments are studied in Lake Lauzon, Montcalm County, P. Quebec, Canada.
Abstract: The rate and the thoroughness of the decomposition of plankton remains are important factors in the cycles of some nutrients in lakes. Experimental data on the mineralization of plankton in vitro are available, especially of marine organisms, but quantitative observations on this process in nature are not mentioned in the literature. This paper presents the results of such observations, made in Lake Lauzon, Montcalm County, P.Q., by means of a sediment collector described in an earlier paper. The chemical composition of plankton, of sediment collected at the 11-meter level, and of surface bottom sediments are studied. Most of the decomposition of the sinking detritus takes place in the epilimnion of the lake. Sediment collected at the 11-meter level, in weekly intervals, shows a remarkable resemblance in composition with the surface bottom sediments. Most of the nitrogen is liberated in the upper 11 meters of water. The liberation of phosphorus seems to be slower and the surface bottom sediments are actua...
TL;DR: The standing crop in 20 lakes shows an inverse relation to mean depth which is interpreted as indicating that, in most of these lakes, the trophic condition is greatly influenced by morphometry, and variations from this relation appear to be explained by the secondary effects of climate and edaphic situation.
Abstract: Plankton sampling has been a part of the program in a number of investigations of lakes in western Canada during the past 20 years. The techniques chosen for this work are discussed and criticized. The resulting data on average standing crop of net plankton are summarized and considered in relation to the kinds of lakes represented. The standing crop in 20 lakes shows an inverse relation to mean depth which is interpreted as indicating that, in most of these lakes, the trophic condition is greatly influenced by morphometry. Deviations from this relation appear to be explained by the secondary effects of climate and edaphic situation.The difference in quantity between the standing crops of net plankton in oligotrophic and eutrophic lakes is not large, and, of course, these lake types intergrade. This lack of sharp differentiation is further obscured by rapid and extensive seasonal fluctuation in amounts of plankton and by the difficulties inherent in present methods of sampling. These circumstances render ...
TL;DR: A large fraction of yearlings produced in the lake fail to migrate from it and live there into their second or third year of life, and are readily taken by trolling or netting in the tributary streams above.
Abstract: A few hundred to one or two thousand cohoes enter Cultus Lake each year, while the Sweltzer Creek population below it is several times as large. "Jack" (age II) fish usually predominate over older male cohoes at the lake. Spawning in the lake or in tributary streams above yields downstream migrations of some hundreds of fry and, a year later, up to a few thousand yearling smolts. These, on the average, amount to 0.13 per cent of eggs in spawners, or only 3 smolts per female. This does not suffice to maintain the coho run into the lake, which is, therefore, heavily recruited from creek-bred fish each year. There are also a very few age-II seaward migrants, which largely return from the sea the same year. Of yearling smolts marked in 1927, 8 per cent returned to the lake after one and a half year's absence.A large fraction, probably the majority, of yearlings produced in the lake fail to migrate from it and live there into their second or third year of life. They are readily taken by trolling or netting in ...
TL;DR: The results of 385 previously published hydrographic stations in the Bay of Fundy are summarized, and the average distribution of salinity at various depths is derived from these data.
Abstract: The results of 385 previously published hydrographic stations in the Bay of Fundy are summarized, and the average distribution of salinity at various depths is derived from these data.The total qua...
TL;DR: A survey in November 1951 indicates the presence of alternate bands of cold and warm water in the slope water and suggests that these are the direct result of instability in the northern edge of the Gulf Stream.
Abstract: The slope water off the Scotian Shelf forms a well-defined band between the coastal waters and the Gulf Stream. Its boundaries fluctuate widely with no apparent systematics, sometimes transgressing upon the Shelf.A survey in November 1951 indicates the presence of alternate bands of cold and warm water in the slope water and suggests that these are the direct result of instability in the northern edge of the Gulf Stream. Observed velocities support such a hypothesis. Temperature-salinity relationships indicate that the slope water is formed of waters from the surface layers of the Gulf Stream, surface coastal waters, Labrador waters and deep Atlantic waters which have upwelled under the Gulf Stream.
TL;DR: Grand monthly means of daily observations of surface sea-water temperature and salinity from twelve light stations along the British Columbia coast during the 13 years 1935 to 1948 have been analysed.
Abstract: Grand monthly means of daily observations of surface sea-water temperature and salinity from twelve light stations along the British Columbia coast during the 13 years 1935 to 1948 have been analys...
TL;DR: Under natural conditions no significant difference existed in the respective catches of the spring salmon underyearlings moving downstream on either side of the canal, but a significant difference was obtained when a narrow beam of light was directed into the water at a downstream angle in front of one net.
Abstract: Experiments to deflect young spring salmon during their night-time migration by means of a beam of light and/or a "wall" of bubbles were conducted in a canal near Courtenay, B.C. By use of hoop nets it was discovered that under natural conditions no significant difference existed in the respective catches of the spring salmon underyearlings moving downstream on either side of the canal. A significant difference was obtained, however, when a narrow beam of light was directed into the water at a downstream angle in front of one net. A reduction to about one-third the expected catch resulted with either continuous or flashing light. The "wall" of bubbles, in a similar position, did not reduce the catch.Cut-throat trout fry and hatchery-reared Kamloops trout fingerlings were not deflected under these conditions.
TL;DR: Infestation experiments carried out in 1947 and 1948 showed that the harbour seal was a definitive host of a larval nematode found in the flesh of the Atlantic cod, smelt, Canadian plaice and eelpout, and adult worms recovered from experimentally infested seals were identified as Porrocaecum decipiens.
Abstract: Infestation experiments carried out in 1947 and 1948 showed that the harbour seal (Phoca vitulina) was a definitive host of a larval nematode found in the flesh of the Atlantic cod (Gadus callarias), smelt (Osmerus mordax), Canadian plaice (Hippoglossoides platessoides) and eelpout (Macrozoarces americanus). Adult worms recovered from experimentally infested seals were identified as Porrocaecum decipiens. Some larval Porrocaecum in the four species of fishes studied were P. decipiens.The worms lost their larval characteristics by moulting between the third and sixth day following introduction into the seal. Sexual maturation proceeded rapidly after the eleventh day and some males and females matured before the twentieth day. Maturation was accompanied by a distinct increase in size.
TL;DR: The quantitative sampling of plankton by pumps, water samplers, tow nets, plankton traps and the Clarke-Bumpus sampler is discussed and a new instrument, the Toronto Sampler, developed at the Ontario Fisheries Research Laboratory, is described and its performance is assessed.
Abstract: A discussion of the composition and distribution of plankton organisms forms a basis for the presentation of a critical review of methods of plankton collection. The quantitative sampling of plankton by pumps, water samplers, tow nets, plankton traps and the Clarke-Bumpus sampler is discussed. Data of a comparative nature dealing with some of the more usual methods are presented. A new instrument, the Toronto Sampler, developed at the Ontario Fisheries Research Laboratory, is described and its performance is assessed.
TL;DR: The color of 184 humpback whales (Megaptera nodosa) was studied at the Coal Harbour whaling station on Vancouver Island during the summers of 1949, 1950 and 1951.
Abstract: The colour of 184 humpback whales (Megaptera nodosa), was studied at the Coal Harbour whaling station on Vancouver Island during the summers of 1949, 1950 and 1951. The colour of the throat region, the flippers and the flukes were classified separately, according to the amount of white present in each of these three regions. Humpback whales from the coast of British Columbia differ from those taken at South Georgia, South Africa, New Zealand and Madagascar in being darker in colour. Males are lighter in colour than females, on the average. No definite change in colour occurs with increase in length.
TL;DR: It is shown how variations in feeding habits, reproductive patterns, and other aspects of population behaviour have required modifications of the basic theory in order to make it applicable to particular species.
Abstract: Classical theories of population growth and inter-species relations are briefly reviewed. It is shown how variations in feeding habits, reproductive patterns, and other aspects of population behavi...
TL;DR: Two species of lampreys and three fishes were found in theLake Cowichan, plus a number of Salmonidae whose occurrence is described elsewhere, in 1940 at least.
Abstract: Cowichan Lake is 34 kilometres long, up to 4 kilometres wide and up to 150 metres deep, with an area of 62 square kilometres. Its average depth is 51 metres. Its shores are of precipitous rock for over half their length, the remainder being boulders or gravel, with a very little marsh.Summer surface temperatures are usually close to 20 °C., while the winter minimum in 1938 was 5.0°. Oxygen is generally abundant in the lake, the lowest value observed being 3.4 cc. per litre, just before the fall overturn (November 24, 1939). The reaction of the water is alkaline (pH 7.0–7.8), and its bicarbonate content was 18–22 mg. per litre (as CaCO3).Lists are presented of organisms collected in the lake. The plankton is reasonably rich in variety but was poor in quantity, in 1940 at least. Bottom organisms also are not abundant. Two species of lampreys and three fishes were found in the lake, plus a number of Salmonidae whose occurrence is described elsewhere.
TL;DR: Development, beginning in 1876, of heavy fishing for "sardines", the yearling herring available in and near Passamaquoddy Bay between New Brunswick and Maine, was followed by decrease in numbers of older fish, and the very local and very fat "Quoddy River" herring disappeared promptly.
Abstract: Development, beginning in 1876, of heavy fishing for "sardines", the yearling herring available in and near Passamaquoddy Bay between New Brunswick and Maine, was followed by decrease in numbers of older fish. The very local and very fat "Quoddy River" herring disappeared promptly. The immense accumulated stock of large spawning herring lasted ten years or more after recruitment was thus greatly reduced. This stock was being coincidently shifted from the Quoddy region, apparently owing to reduced rainfall.The normal seasonal shifting of these fish is between the outer side of Grand Manan Island in summer and near the mainland in winter. In midsummer of 1877, their numbers at Grand Manan began to diminish and for four years remained very low. They were as abundant as ever in winter near the mainland, but farther from shore and more numerous eastward. They appeared inside the Reversing Falls of the Saint John River, whose outflow goes to Grand Manan, in all four years of their scarcity at Grand Manan. Large...
TL;DR: By a modification of the DeLury method an estimate is made of the stock of lemon sole on the fishing grounds in Hecate Strait, British Columbia based on the trend in catch of tagged fish per unit of effort in relation to accumulated catch of tagging fish.
Abstract: By a modification of the DeLury method an estimate is made of the stock of lemon sole (Parophrys vetulus) on the fishing grounds in Hecate Strait, British Columbia. The method is based on (1) the trend in catch of tagged fish per unit of effort in relation to accumulated catch of tagged fish, and (2) the trend in catch of untagged fish per unit of effort in relation to accumulated catch of untagged fish. At the start of the experiment 4.72 million pounds are estimated to have been present, while during the experiment 3.74 million pounds entered the area of fishing, 3.26 million pounds emigrated from it, and 2.54 million pounds were caught.A Petersen-type estimate based on the ratio of tagged to untagged fish was 4.70 million pounds present at the start of the experiment—practically identical with the one derived from catch-effort information. Total population for the year (1950) is estimated as 9.8–12.2 million pounds, including catch and possible emigration prior to the experiment, the stock on the fishi...
TL;DR: Chum and coho salmon fry respond positively to changes in water flow by swimming against the current as discussed by the authors, and the magnitude of the response varies with the intensity of the current.
Abstract: Chum and coho salmon fry respond positively to changes in water flow by swimming against the current. The magnitude of the response varies with the intensity of the current. Currents eliciting opti...
TL;DR: Larval development up to the three-segmented stage is illustrated, and supports the inclusion of Micronereis in Nereidae.
Abstract: Micronereis nanaimoensis sp. n. is described from the region of Nanaimo, British Columbia. The definition of Micronereis is slightly emended to include the species. It differs from its only congener, M. variegata Claparede of Europe, in being much larger, in possessing palps, in having more varied setae and different specialized crotchets in the males, and in colour. Swarming, pairing and egg-laying occur from late March to the end of May. The eggs are moulded by the female into masses covered by jelly, which are deposited on leaves of Zostera, Ulva, or other seaweeds, near low-tide mark, and are accompanied by her in the jelly until the larvae become free-swimming. In the laboratory, larvae left the egg-mass after 10–16 days, in cold water. Larval development up to the three-segmented stage is illustrated, and supports the inclusion of Micronereis in Nereidae.
TL;DR: Oceanographic study of six inlets along the Labrador coast shows that their water comes primarily from the cold Labrador current, with some freshening and warming of the upper layers of all inlets and in the coastal waters.
Abstract: Oceanographic study of six inlets along the Labrador coast shows that their water comes primarily from the cold Labrador current. Below 50 meters, temperatures are characteristically below zero, and salinities usually between 32 and 33‰. The principal exception is Lake Melville, which, although below zero, is very slightly warmer and freshened to 26–29‰. In summer there is some freshening and warming of the upper layers of all inlets and in the coastal waters; this being detectable down to about 40 meters, or exceptionally to 100 meters. None of the inlets contained stagnant bottom water, although all but one were much deeper inside than at the "threshold". Comparison of 1926 and 1949 observations in similar adjacent inlets gives no indication of warming of the bottom waters over that period.
TL;DR: A comparison of the actions of a commercial leather bate, hog intestinal mucosa, papain, pancreatin, trypsin and the caecal enzyme of red fish on casein led to the conclusion that the pyloric caeca of redfish would furnish a suitable material from which to prepare a leather bates.
Abstract: The proteolytic activity of an enzyme preparation from the pyloric caeca of redfish (Sebastes marinus) was studied and measured colorimetrically by the biuret reaction. The optimum temperature of this preparation was found to be 51–52 °C. A statistical study of the data showed the optimum pH to be 8.75, or slightly higher than the optimum pH of trypsin. A comparison of the actions of a commercial leather bate, hog intestinal mucosa, papain, pancreatin, trypsin and the caecal enzyme of redfish on casein led to the conclusion that the pyloric caeca of redfish would furnish a suitable material from which to prepare a leather bate.