bluuebunny/crossref_metadata_2025 huggingface dataset:
Amines in Fish Muscle. V. Trimethylamine Oxide Estimation
Authors: Dyer W. J. , Dyek F. E. , Snow J. M.
Published: April 2011

The Lintzel method of trimethylamine oxide determination was found to give low results when less than 2 to 5 mg. oxide nitrogen was present. By suitable modification this could be reduced to 2 mg. above which a constant 96 per cent recovery was obtained. However, many fish extracts contain only 0.5 to 2 mg. nitrogen in the aliquot which can be used for the reduction.A modified Norris and Benoit procedure, which is much simpler to use, was developed. This gave about 96 per cent recovery down to about 0.4 mg. nitrogen. Extraction of the fish muscle with either trichloracetic acid or formaldehyde was satisfactory.
Skeena River Sockeye Escapement and Distribution
Authors: Brett J. R.
Published: April 2011

Population estimates made from observations on the number of sockeye salmon in the various spawning streams of the Skeena River, B.C., during the period 1944–48 are presented. The methods used include a fence count at Babine Lake, the most important spawing area, supplemented by stream counting in the other areas and sample tagging at Lakelse. Estimates made at Babine by the latter methods were compared with the fence counts; the stream count estimates were about one-third of the actual number present, whereas estimates from tagging were about twice the actual.A brief description of the spawning streams of the Skeena is accompanied by a map showing their location. Best estimates of 1946–47 escapements to major spawning areas are: Babine, 480,000; Morice, 70,000; Bear, 42,000; Lakelse, 29,000. These comprise 92 per cent of the total for the river system. The area of the spawning beds used by sockeye in the system is about 100 acres, or of the order of 1.5 square yards per spawning pair. The division of the whole run is approximately 45 per cent to the commercial fishery, 6 per cent to the Indian fishery, and 49 per cent escapement.
Further Ostracoda of the Vancouver Island Region
Authors: Smith Verna Z.
Published: April 2011

New distribution is given for Conchoecia elegans G. O. Sars and C. spinirostris C. Claus. Ten new species are described: Philomedes carcharodonta, Pontocypris clemensi, Cythere alveolivalva, C. uncifalcata, Hemicythere bicarina, Cythereis serridentata, Loxoconcha dentarticula, L. tenuiungula, Paradoxostoma fraseri, P. striungulum. Cythereis obesa Lucas is placed in Hemicythere.
A Comparative Study of Anadromous and Freshwater Populations of Brook Trout (Salvelinus fontinalis (Mitchill))
Authors: Wilder D. G.
Published: April 2011

Anadromous and freshwater populations of Salvelinus fontinalis have been compared to determine the taxonomic relationship of the sea trout and brook trout. Sea trout and freshwater trout differ seasonally in coloration and flesh colour but these differences appear to be environmental in origin rather than hereditary. Freshwater trout reared to hatching at 5.5 °C. had larger head parts, deeper and wider bodies, longer fins, more pectoral rays, dorsal rays, and branchiostegals but fewer scale rows and anal rays than those of common parentage reared at 0.9 °C. Sea trout and freshwater trout from the same river differ less in body form than trout of common parentage reared at different temperatures and less than four populations of freshwater trout. Differential development of the secondary sexual characteristics accounts for most of the differences in body form between sea and freshwater trout. Sea trout and freshwater trout from different rivers reared under the same conditions differed less in body form than any of the other populations compared. Sea and freshwater trout did not differ significantly in any of the meristic structures counted. Seasonal differences in weight-length relationship related to spawning and feeding habits were observed. Sea trout grow rapidly during the year in which they first migrate to the sea but subsequent growth is not appreciably faster than freshwater trout from the same river. Exposure of freshwater trout to sea water indicates that some could survive typical sea trout migrations. No evidence was obtained to indicate hereditary differences in migratory behaviour. Evidence available indicates that sea and freshwater trout of Moser River, Nova Scotia, constitute one taxonomic unit.
The Biology of the Surface Zone Zooplankton of a Boreo-Arctic Atlantic Ocean Area
Authors: Kielhorn William V.
Published: April 2011

Zooplankton samples were taken from the surface zone waters of the central Labrador Sea at International Ocean Station "B" (56° − 30′N., 51° − 00′W.) at weekly intervals throughout one calendar year for the purpose of determining the composition of the zooplankton, the seasonal progression, fluctuations and pertinent physical factors. An attempt was made to correlate the physical and biological factors.Ships of the United States Coast Guard and the Royal Canadian Navy were used as collecting units, and these were provided with nets, samplers and other equipment with which to carry out the shipboard phase of the investigation. Mid-day, 20 minute oblique hauls from 150-0 metres were made with the Clarke-Bumpus plankton sampler using No. 2 and No. 12 mesh silk nets, along with bathythermograph and Secchi disc lowerings. Later in the day, but at least one hour after dark, an open half-metre net 20 minute surface tow was made for additional qualitative data. Bioluminescence records also were obtained at this time.All available physical and biological data pertaining to the area under investigation were examined to provide a basis for comparison.Synopses of the species found in the material are presented individually, including their seasonal occurrence, probable breeding seasons, numerical and economic importance, and values as indicator forms. In all, 61 species in seven phyla, 10 classes and 17 orders are represented.The zooplankton population of the surface zone in the central Labrador Sea is characterized by relatively few species, but at the same time by large numbers of individuals. The plankton consists mainly of Calanus finmarchicus, Thysanoessa longicaudata, Oithona atlantica, Scolecithricella minor, Oikopleura labradoriensis and Eukrohnia hamata. The remainder of the species assume comparatively minor importance in the economy of the region.The main augmentation season was found to occur generally in late summer, although mid-winter breeding was noted for a few animals. The zooplankton of this region was found to be distinctive, being consistently oceanic, but neither true arctic nor true boreal. Definite biological evidence was obtained that indicated the influx of boreal-subtropical surface waters into the area in winter.Extinction coefficients determined from white Secchi disc readings are graphed, as are comparisons between black and white disc readings. It was concluded that the great variations of transparency were caused by fluctuations in the amount and kinds of phytoplankton and detritus in the water, and that the zooplankton density had little effect on water clarity.No direct correlation was noted between the occurrence of bioluminescence and individuin species or planktonic groups, but it was found that the greatest bioluminescence was observed al the summer and fall.
Temperature Tolerance in Young Pacific Salmon, Genus Oncorhynchus
Authors: Brett J. R.
Published: April 2011

Lethal limits of high and low temperatures were determined for the young of five species of Pacific salmon, the spring (Oncorhynchus tshawytscha), the pink (O. gorbuscha), the sockeye (O. nerka), the chum (O. keta) and the coho (O. kisutch).For acclimation temperatures ranging from 5° to 24 °C. significant differences between species in their resistance to high temperatures was obtained. The spring and coho were most resistant. The pink and chum salmon were least resistant, and the sockeye was distinguishable from the latter two by greater resistance for prolonged exposure to high temperatures. No species could tolerate temperatures exceeding 25.1 °C. when exposed for one week.A fanning-out of the opercula was shown to be directly correlated with the onset of death from a low temperature. By use of this criterion mixed lethal effects at low temperatures were demonstrated and found to be influenced by the size of the fish and by the salinity of the water. None of the species could withstand temperatures lower than 4 °C. when acclimated to 20 °C. and above. When taken from holding troughs as low as 5 °C., coho and sockeye could not tolerate long exposure (four days) to 0 °C.In a vertical gradient little difference in preferred temperature was observed, either between species or for different acclimation temperatures. The 12° to 14 °C. stratum was the region of greatest concentration.Specific differences in temperature responses are in keeping with taxonomic and ecological distinctions.
The Morphometry of the Coregonine Fishes of Great Bear Lake, N.W.T.
Authors: Kennedy W. A.
Published: April 2011

Morphometric measurements and counts were made on representative samples of 78 lake whiteflsh Coregonus clupeaformis, 77 ciscoes Leucichthys artedi and 8 round whitefish Prosopium cylindraceum from Great Bear Lake, N.W.T. The amount of variability found within this homogeneous population of whitefish casts doubt on the validity of some of the species of whitefish which have been described from this region. The same can be said of the ciscoes.
Micronereis nanaimoensis sp. n.: with some Notes on its Life-History
Authors: Berkeley E. , Berkeley C.
Published: April 2011

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 Claparède 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.
The Mineralization of Plankton
Authors: Kleerekoper Herman
Published: April 2011

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 actually enriched with this element. Silica is enriched at both the 11-meter level and the bottom of the lake, mainly through the settling of diatom frustules. Hydrolysis of organic matter in the upper 11-meter column of the lake decreases in the course of the summer. Mineralization seems to be practically halted in the oxygen-poor hypolimnion.
Preparation and Viscosity of Chitosans
Authors: Lusena C. V. , Rose R. C.
Published: April 2011

not available
Growth Hormone from Salmon Pituitary Glands
Authors: Jampolsky A. , Hoar W. S.
Published: April 2011

Injections of an alkaline extract of the anterior lobe of beef pituitary produced a prolonged acceleration of growth in rats and a temporary increase in weight of goldfish. A comparable extract of salmon pituitaries (Oncorhynchus tshawytscha) had no effect on growth of rats but produced a slight temporary increase in growth of goldfish. Negative effects of salmon extracts on rats are considered significant, but all effects on goldfish are questioned since the extracts were not free of toxicity.
Odour Perception and Orientation in Fishes
Authors: Hasler Arthur D.
Published: April 2011

not available
The General Oceanography of the Strait of Belle Isle
Authors: Huntsman A. G. , Bailey W. B. , Hachey H. B.
Published: April 2011

Hydrographic data for late August, 1923, show for the Strait (a) progressive inward movement on the north side of Arctic or sub-Arctic water, (b) progressive outward movement on the south side of Gulf water and (c) a dominant outward flow with evidence of a previous dominant inward flow. Time differences suggest tidal causes for the marked temperature and salinity changes. Current measurements for a double tidal period indicate residual trends of nine and eight miles per day in opposite directions on the north and south sides of the Strait. Inside, the Esquiman Channel shows two contra-clockwise eddies north and south of the Mekattina Bank. In addition, hydrographic data show a strong northeasterly movement along the Newfoundland shore and a weaker southwesterly one along the opposite Quebec shore.Planktonic animals indicate the water movements, Mertensia, Acartia spiniremis, Themisto, Pseudalibrotus and Oikopleura vanhöffeni surviving to various degrees in the water from the Labrador Current that reaches the centre of the Gulf along the north shore of the Strait and Channel. Other forms characterize the warm shallow water along the Newfoundland shore inside the Strait and show its movement outward to the east coast of Newfoundland. The Greenland seal fishery of winter reflects the inward movement from the Labrador Current. Cod and herring fisheries invade this cool water of the north shore only locally in summer with access of warmer water from the south shore. Lobsters and cunners are very abundant in, but particularly confined to, the warm shallow water mentioned above.
Some Aspects of Olfactory Perception in Migrating Adult Coho and Spring Salmon
Authors: Brett J. R. , MacKinnon D.
Published: April 2011

A series of tests were conducted to investigate the sense of smell in migrating coho (Oncorhynchus kisutch) and spring salmon (O. tshawytscha). By pouring dilute solutions of each of 54 substances into the path of the salmon moving up a fish ladder at Stamp Falls, B.C., positive responses were noted by recording changes in the rate of migration. Representative samples of alcohols, aldehydes, ketones, esters, organic acids and oils, as well as shark repellent and a pulp-mill effluent caused no significant change in the migration. However, dilute water rinses of mammalian skins had distinct repellent action. An acute olfactory sense enabling adult Pacific salmon to detect predators from a downstream position was considered to have survival value. The use of mammalian predator skins to repel salmon from destructive river locations is suggested.
Three Kinds of Whale-Lice (Cyamidae: Amphipoda) from the Pacific Coast of Canada, including a New Species
Authors: Margolis L.
Published: April 2011

Three species of "whale-lice" (Cyamidae: Amphipoda) are recorded from whales caught in Canadian Pacific seas: Cyamus scammoni Dall, 1872, from Rhachianectes glaucus; Cyamus catodontis n. sp., from Physeter catodon; and Paracyamus boopis (Lütken, 1870), from Megaptera nodosa. Cyamus catodontis is described and illustrated.
Temperature-Salinity Relations and Mixing on the Scotian Shelf
Authors: McLellan H. J.
Published: April 2011

Miller's method of studying mixing processes is extended to the examination of the characteristics of waters on the Scotian Shelf against a five-pointed grid. The use of the modified T-S theorems and the less rigorous definition of water types make T-S analyses rewarding in this area. Some light is shed upon the mixing processes and movement pattern on the Scotian Shelf.
New Stoneflies (Plecoptera) from Western North America
Authors: Jewett Jr. Stanley G.
Published: April 2011

Descriptions are presented of the new species Capnia cygna, C. petila, C. porrecta, C. sexluberculata and Isoperla rainiera. For seven already-named species, previously unknown male or female adults or nymphs are described.
The Trophic Status of Port John Lake, British Columbia
Authors: Robertson J. G.
Published: April 2011

Port John Lake is situated on King Island on the central British Columbia coast. Area is about 0.35 square miles (910,000 sq. m.). The drainage basin is 3.6 square miles (9.3 sq. km.) with an igneous foundation supporting a coniferous forest. Annual precipitation is 116 inches (295.5 cm.). An oligotrophic lake, it has a volume development of 1.53 and a mean depth of 82.2 feet (25.1 m.). The thermal stratification is second order, temperate, of the Whipple classification. The summer heat income is approximately 11,000 gram-calories per sq. cm. The ratio of O2 in the hypolimnion to O2 in the epilimnion is 6.58. Total dissolved solids are 39 ppm. at the lake surface.Large amounts of organic matter are washed into the lake imposing a potential stress on its oligotrophy. However, dredge and net collections, which are dominated by chironomids and cladocerans, respectively, contained very few organisms. Plankton was most abundant in the surface water.Low production of organisms is partly the result of the heavy rainfall which dilutes the trophic stratum above the hypolimnion, and the small amount of sunlight reaching the lake.
Tidal Currents in Juan de Fuca Strait
Authors: Herlinveaux R. H.
Published: April 2011

Three series of direct current observations taken in Juan de Fuca Strait in 1952 have been analysed. A linear relationship between the difference in sea level on the ocean coast and the Strait of Georgia and tidal currents has been shown. This relation holds from the surface to the lower depths. The current velocities in a cross-section can be predicted at any time. These sections show that the ocean water tends to intrude along the bottom on the flood, expanding upward and favouring the southern shore. The ebbing water is first noticed in the middle of the strait, then it expands down and across favouring the northern shore. The ebb current is stronger at the surface, and the flood current stronger near the bottom. Surface current predictions are shown to be comparable to the U.S. Coast and Geodetic Survey tidal predictions. From this it is reasonable to believe that the predicted tidal currents at the lower depths should also be valid.
The Oxygen Supply to Salmon Eggs in Spawning Beds
Authors: Wickett W. Percy
Published: April 2011

By using standpipes set 12 inches into the stream bottom the oxygen content and apparent velocity of the gravel water in the controlled-flow section of Nile Creek were observed. Values of dissolved oxygen content and velocity that just supply the full oxygen demand of salmon eggs were defined. The high mortalities of chum salmon eggs in the pre-eyed stage, that have been found in certain areas, may be explained on the basis that oxygen demands of 0.00013 to 0.0003 mg./egg/hr. at temperatures of 0.1° to 8.2 °C. were not being met, owing to very low oxygen content or very low apparent velocity of the water in the gravel. Values as low as 0.2 p.p.m. and 2 mm./hr. were recorded. A portable gravel-water sampler is described, which can be used (1) to obtain samples of subsurface water for the determination of dissolved oxygen; and (2) to calculate apparent velocity of gravel water from rate of dilution of an added dye.
Studies of the Trematode Stephanostomum baccatum (Nicoll, 1907): I. The Distribution of the Metacercaria in Eastern Canadian Flounders
Authors: Wolfgang R. W.
Published: April 2011

Stephanostomum baccatum, an acanthocolpid trematode, encysts during its larval stage in eastern Canadian flounders, the most consistently and heavily infected species being the winter flounder, Pseudopleuronectes americanus (Walbaum). The infection is heaviest in Passamaquoddy Bay. Hosts are usually more heavily infected in inshore than in offshore waters. Infections are light in the Bras d'Or Lakes and the northern Gulf of St. Lawrence. Larger fish have heavier infections than smaller fish. S. baccatum infects both European and North American flounders; two of its hosts occur on both sides of the Atlantic: the witch, Glyptocephalus cynoglossus (L.), and the American plaice (European long rough dab), Hippoglossoides platessoides (Fabric.).
Cestode and Nematode Infection of Sockeye Smolts from Babine Lake, British Columbia
Authors: Dombroski E.
Published: April 2011

Of the 1-year-old sockeye (Oncorhynchus nerka (Walbaum)) smolts migrating from Babine Lake in 1952 and 1953, in each year about 35% were infected with the cestode Eubothrium salvelini (Schrank, 1790) and 20% by the nematode Philonema oncorhynchi Kuitunen-Ekbaum, 1933. Six to 7% of the smolts harboured both parasites. Fish infected by cestodes only or cestodes and nematodes were significantly smaller than uninfected fish or those with nematodes only. This indicates that the cestode infection retards growth. Nematode-infected smolts were significantly larger than the uninfected individuals in 1952 but not so in 1953.
The Smallmouth Bass Fishery of South Bay, Lake Huron
Authors: Fraser J. M.
Published: April 2011

The smallmouth bass (Micropterus dolomieui) population of South Bay, Lake Huron and the sport fishery imposed on it have been studied by means of marking and creel census carried out during the years 1947 to 1952 inclusive. Population estimates of legal-sized bass (over 10 inches–fork length), based on the recovery of marked fish, show a decrease from 5,900 fish in 1947 to 2,900 in 1949 with an increase again to 5,700 in 1952. The number of bass caught per 100 rod-hours in these years was 89, 51 and 87, respectively. The recovery of the population from its low in 1949 was due solely to the 1947 year-class which dominated the fishery in 1950, 1951 and 1952, contributing 34%, 71% and 67%, respectively, of the anglers' catch in these years. Analysis of scale samples of the anglers' catch shows considerable variation in year-class strength. In contrast to the 3,500 fish contributed to the anglers' creel by the 1947 year-class, the 1945 year-class contributed only 400 fish.South Bay bass enter the sport fishery in small numbers at age III and 70% of the anglers' catch consisted of age-III to age-V fish. Sixty per cent of the legal-sized population of bass present in South Bay in one year are taken by anglers in the succeeding 4–5 years at the present exploitation.A large percentage of the bass population is located in the Inner Basin of South Bay where they are dispersed in varying concentrations along the shoreline. During the five-year study 3,331 bass were tagged and, although the loss of tags was high, 692 were recaptured by trap nets in the same season they were released. Eighty-five per cent of these were taken within two miles of their release point. Of 60 bass recaptured a year after tagging, 43 (72%) were taken within two miles of their release point. Only five per cent of all recorded recaptures were caught over five miles from their release point. Larger bass tended to range farther than small bass.
A Method for Removing the Effect of Recruitment on Petersen-type Population Estimates
Authors: Parker Richard A.
Published: April 2011

A regression analysis, which is based on time changes in the ratio of the number of marked fish in the daily catch to the total daily catch, was used to estimate initial population size. This method eliminates overestimation caused by recruitment.
A Statistical Examination of Anisakis Larvae (Nematoda) in Herring (Clupea pallasi) of the British Columbia Coast
Authors: Bishop Yvonne M. M. , Margolis Leo
Published: April 2011

The presence of larval Anisakis in British Columbia herring was examined during the winter fisheries of 1950–51 and 1951–52. In the commercial catches in the Strait of Georgia the incidence was found to be between 80 and 90%. In Hecate Strait, on the west coast of Vancouver Island and in the mainland coastal area of Queen Charlotte Sound it was between 90 and 100%. The intensity of infection varied greatly in different fishing areas (i.e. in different herring populations). Generally, the maximum level of infection occurred in the Queen Charlotte Sound coastal regions, and decreased both north and south of this area. Fish on the west coast of Vancouver Island were more heavily infected than those on the east coast (Strait of Georgia). The level of infection increased with age, I-year fish (i.e. fish in their first year of life) being uninfected. The intensity of infection remained constant throughout the winter for any particular age and area and was the same for both sexes. In most areas the level of infection was a little lower in 1951–52 than in 1950–51.
Blood Levels of Hemoglobin and Lactic Acid in some Freshwater Fishes Following Exercise
Authors: Black Edgar C.
Published: April 2011

During the summers of 1953 and 1954 the effects of forced activity on two blood constituents were investigated in seven species of fresh-water fishes, representing six families. The fish were hatchery-raised or captured from lakes in the southern Okanagan Valley, and the experiments were carried out in the Summerland Trout Hatchery, Summerland, B.C. Following forced exercise for 15 minutes in water at 11.5 °C. the hemoglobin level increased significantly in only one species and the lactic acid increased significantly in all species. There appears to be a correlation between the average value of lactic acid following exercise and the activity of the fish, and also with the position of the species with respect to summer water temperature.
Age, Maturity, Spawning and Food of Burbot, Lota lota, in Lake Winnipeg
Authors: Hewson L. C.
Published: April 2011

Burbot are common in Lake Winnipeg; 886 were taken as a sample. Trap-net and otter-trawl catches are more representative of the population than gill-net catches. A significant difference in length-weight relationship exists between two localities. Ages were determined from otoliths. Heavier exploitation in the northern part of the lake probably accelerated the growth rate. Age-6 burbot there weighed 3.4 pounds compared with 2.6 pounds in the southern part. Spawning begins about January 31 and lasts 3 weeks. The smaller burbot feed mainly on insect larvae, the larger burbot on fish and crayfish.
The Net Plankton of Great Slave Lake
Authors: Rawson D. S.
Published: April 2011

The net plankton of Great Slave Lake was studied extensively in the years 1944 to 1947 and sampling continued at a central station through 1954. Some 490 samples were taken using large nets and traps with No. 20 silk. Taxonomic, gravimetric and numerical analyses are reported and comparisons made between the larger, open lake and the deep, cold, east arm.Among 160 species of algae, two diatoms, Melosira islandica and Asterionella formosa were dominant. Green and blue-green algae were scanty but Dinobryon was numerous, especially in the cold, east arm. Among 26 rotifers Keratella cochlearis and Kellicottia longispina were dominant and four other species common. Cladocera were scarce but the copepods made up about 85% of the plankton volume. Diaptomus spp., Cyclops spp., Limnocalanus macrurus, Epischura lacustris and Senecella calanoides were the main species.The average dry weight of the standing crop of net plankton in the open water was 21.8 kg./ha. The crop was heavier in years of warm water than in those of colder water. Occasional high turbidity was associated with decreased plankton. In Christie and McLeod Bays of the east arm, where the waters are deeper, colder and lower in mineral content, the average dry weight of plankton was 14.3 and 9.0 kg./ha. These amounts are typical of the plankton in large, very oligotrophic lakes.An early season maximum of diatoms and copepods was followed by a rapid decline in late July. The smaller, late-summer maximum included large numbers of rotifers. More than half of the plankton was in the upper 25 metres with decreasing amounts down to 100 metres. A thin plankton, mainly of copepods, extends down to 600 metres.The dominant species of plankters in the open water of Great Slave Lake appear to be almost identical with those of Lake Winnipeg, Lake Nipigon and the Great Lakes. All have a diatom-copepod type of plankton with a constant group of rotifers and Dinobryon in moderate numbers. Green and blue-green algae are scanty except in the shallower and warmer lakes, Winnipeg and Erie.
Storage of Frozen Plaice Fillets
Authors: Dyer W. J. , Morton Margaret L.
Published: April 2011

Taste panel assessments of taste, texture, and grade, and estimations of soluble actomyosin and of fat spoilage on plaice fillets after frozen storage at + 10°F. (−12 °C.) are reported. The plaice became unpalatable at 6 to 7 months as compared with 2 to 3 months for cod and about 8 months for Atlantic halibut at +10°F. Ascorbic acid was not effective in preventing lipid deterioration. A relationship between protein denaturation and the lipid content of the fish and its deterioration is suggested.
Effects of Temperature, Salinity and Oxygen on the Survival of the American Lobster
Authors: McLeese D. W.
Published: April 2011

Thermal acclimation for lobsters transferred from 14.5 °C. to 23.0 °C. is complete in 22 days. Substantial acclimation to low salinity and to low oxygen occurs within one week. Lethal levels of these three factors are not altered by differences in size within the range 16–34 cm., by difference in the areas where lobsters were caught, or by starvation for up to 57 days. Moulting lobsters are less resistant to high temperature, low salinity and low oxygen conditions than hard-shelled lobsters.Upper lethal temperature levels and lower lethal salinity and oxygen levels were investigated for hard-shelled lobsters acclimated to each of the 27 combinations of three levels of temperature (5, 15 and 25 °C.), salinity (20, 25 and 30‰), and oxygen (2.9, 4.3 and 6.4 mg./l.). The upper lethal temperature is raised by an increase in thermal acclimation, and is lowered by a decrease in the salinity and oxygen acclimation levels. The lower lethal salinity is raised by an increase in the level of thermal acclimation and a decrease in the level of oxygen acclimation. It is lowered by acclimation to reduced salinity. The effect of salinity acclimation is not always the same, but depends on the temperature acclimation. The lower lethal oxygen is raised by either an increase in the temperature acclimation level of a decrease in the salinity acclimation.The lower lethal temperature is 1.8 °C. for 17° acclimated lobsters, and 5.0° for 27.5° acclimated lobsters.Ultimate and maximum or minimum lethal levels of temperature, salinity and oxygen—the highest and lowest lethal levels that can be attained by acclimation—were interpolated from the results. These measures were used to integrate the lethal levels of the three factors into a single three-dimensional graph which describes the boundary of lethal conditions for lobsters exposed to the three factors operating together (Fig. 7).
Storage of Frozen Rosefish Fillets
Authors: Dyer W. J. , Morton Margaret L. , Fraser Doris I. , Bligh E. G.
Published: April 2011

Taste panel assessments of taste, texture, and grade of cooked samples, examination prior to cooking, and analyses of soluble actomyosin and of fat spoilage on frozen rosefish (Sebastes marinus) fillets, with and without treatment with ascorbic acid, stored at −10°F. (−23 °C.) and +10°F. (−12 °C.), are reported.Rosefish fillets stored at +10°F. remained in good condition for 17 to 22 weeks, but became unpalatable in 7 months; stored at −10°F. these conditions applied after 30 weeks and 80 weeks.Ascorbic acid prevented fading of the red pigment and delayed discoloration, but had no effect on the taste panel assessment. Almost no loss in actomyosin extractability occurred at −10°F. up to 85 weeks.
Growth, Mortality and Movements of a Sanctuary Population of Maskinonge (Esox masquinongy Mitchill)
Authors: Crossman E. J.
Published: April 2011

A Schumacher population estimate based on 995 maskinonge taken by trap nets, between the months of May and October in the years 1951–1953, set the number of maskinonge in Nogies Creek at between 769 and 1,122 in July 1953. The mean standard length of these fish was 53.0 cm. The rate of growth (26.3 cm. S.L. in the first year) compared favourably with that for maskinonge in other waters. Fish of age-groups II, III and IV predominated. The small number of fish over four years of age was apparently due to a 70% annual mortality rate at least after the third year of life and perhaps before age III.Recaptures of tagged maskinonge demonstrated that there was little movement of maskinonge in summer, and what movement there was, was mainly upstream. In the fall there was far more movement of fish, and this was mainly in a downstream direction.The area supports a fairly large population of maskinonge but the high mortality after three years of age limits its value for raising maskinonge to legal size. The potential for rearing fish to three years of age is such that it may be very advantageous to move hatchery fish here for one or two years before liberation.
Fecundity of Wild Speckled Trout (Salvelinus fontinalis) in Quebec Lakes
Authors: Vladykov Vadim D.
Published: April 2011

For the present macroscopic study over 1,000 female speckled trout from the Laurentide Park in Quebec have been examined. Of this number, 747 specimens received special attention. In ovaries of adult trout 3 types of eggs were found: recruitment stock (Class a), maturing eggs (Class b) and atretic eggs (Class c). In the process of maturation, the number of eggs of Class b progressively decreases due to atresia, but their diameter becomes greater. Comparisons of fecundity between different trout populations should be made only when eggs are nearly mature. The diameter of ripe eggs just previous to spawning, preserved in formalin, varied from 3.8 to 4.8 mm. There is a direct relation between the number of ripe eggs and the size of the fish: the extreme numbers of eggs were 90 and 4,800 eggs, and the extremes of fork lengths of females were 6 and 22 inches. The fecundity is greater among fish from lakes richer in food. A simplified method of determining the number of eggs in ovaries was devised. The maturity of females was determined by a 7-digit system. The colour of flesh was classified by a 6-digit system.
On the Variation in Bottom Fauna and Fish Yield in Relation to Trophic Level and Lake Dimensions
Authors: Hayes F. R.
Published: April 2011

The relation of area to depth was studied for 500 lakes. Up to 0.3 km.2 the mean depth is constant at 3 to 4 m. This is probably an artifact due to omission of shallow lakes from study. From 0.3 to 300 km.2 the relation of depth to area is linear on a log—log plot. In the largest lakes the depths increase less proportionally.Of the three ways to study fish productivity in lakes, one, the estimate of standing crops, is usually attempted at mean depths around 1 m. Another, angling returns, centers on lakes of 3.5 m., while commercial reports come from lakes of 6.5 m. average depth, and extend to the deepest lakes.Fish records can be conveniently divided into three trophic levels, short food chain, e.g. carp, intermediate, e.g. bluegills and long, e.g. trout, bass. Records are interconvertible by use of factors. By factoring, a productivity index is calculated for some 150 lakes.The productivity index is found to be inversely proportional to mean depth on a log—log plot. Thus by correction of the PI it is possible to derive a theoretical value, called the quality index, for a standard lake 5 m. deep.The QI is intended to screen the effect of depth out of the PI and so disclose the inherent capacity of the lake. The QI values vary around unity. Lakes of mean depth under 2.5 m. are factored as of that depth, it being assumed that primary productivity due to photosynthesis goes on all the way to the bottom.A study of bottom fauna in 250 lakes in several regions gave no indication of a relation between depth and productivity.
An Investigation of the Electrical "Spike" Potentials Produced by the Sea Lamprey (Petromyzon marinus) in the Water Surrounding the Head Region. II.
Authors: Kleerekoper H. , Sibakin Kira
Published: April 2011

The rhythmically recurring spike potentials emitted by Petromyzon marinus are synchronous with the external respiratory movements but are not emitted through the branchial pores. Only total electrical shielding of the probranchial body eliminates these potentials from the water surrounding the animal. The principal area of emission is located in the eye region immediately cephalad of the first pair of branchial pores, in the area overlying the junction of the probranchial muscle and the hypobranchial branch of the parietalis. Probing of the skin with electrodes shows potentials of 1 millivolt on the surface of this area. These potentials are more than tenfold those recorded on any other part of the skin. It is assumed that the spike potentials described previously are emitted from the area defined above.
Mortalities Among Developing Trout and Salmon Ova Following Shock by Direct-Current Electrical Fishing Gear
Authors: Godfrey Harold
Published: April 2011

Two units of direct-current fishing gear, providing terminal potentials of 550 and 150 volts, were used to give shocks of different severities to trout and salmon ova in various stages of development. The purpose of the tests was to establish precautionary measures to prevent damaging eggs when using similar apparatus, in waters of similar conductivity, in the vicinity of natural redds containing live eggs. High terminal voltage caused heavy losses among pre-eyed eggs, considerably fewer losses among eyed eggs, and no losses to eggs that were near hatching. There were no losses among eyed or pre-eyed eggs with low terminal voltage. Eggs that had been buried in the gravel of a stream apparently received some protection from electric shock. Salmon alevins were killed by prolonged severe shock, but not by a similar shock of shorter duration. The alevins showed greatly increased activity and swam about sporadically when in the electric field, but did not exhibit galvanotropic responses of a directional character.
Morphometric Comparison of Three Races of Kokanee (Oncorhynchus nerka) Within a Large British Columbia Lake
Authors: Vernon E. H.
Published: April 2011

Samples of kokanee (land-locked sockeye salmon) drawn from the spawning runs to seven streams tributary to Kootenay Lake, British Columbia, were compared statistically for morphological variation between streams, between lake areas and between years. Kokanee within three major lake areas displayed great similarity in age, size, vertebral count, scale characters and development of secondary sex characters. Samples from a representative stream of each area differed in age at maturity, size, growth rate in the first year, vertebral count, scale row count, gill raker count, head length of males, growth form of caudal peduncle, eye diameter, development of secondary sex characters, ova per unit total weight, and commencement of spawning period. Variation between years in size and vertebral count did not obscure or alter the stability of differences between races over a period of four years. Kokanee straying to spawn in areas not of their natal origin were identified by age, size, vertebral count, scale character, and scale row count, and totalled less than three per cent of 1,131 examined. Progeny of parents from the three races were propagated in a uniform environment from fertilization to six months after hatching. Parental differences in number of vertebrae were transmitted to offspring. Segregation during reproduction, due to strong homing tendencies, is considered the principal isolating mechanism leading to some genotypic divergence and considerable phenotypic variability.
Yellow Discoloration and Deterioration in Frozen Lobster Meat
Authors: Bligh E. G. , Dyer W. J. , Horne D. C.
Published: April 2011

The yellow discoloration which occasionally develops in some Atlantic frozen lobster-meat packs on storage was found to be due to oxidation of the red astacene to a yellow pigment. The discoloration, and the accompanying off-odours and off-flavours, can be minimized by the use of hermetically sealed or vacuum-sealed cans, low storage temperatures, and antioxidants.
Alterations in the Blood Level of Lactic Acid in Certain Salmonoid Fishes Following Muscular Activity.: II. Lake Trout,Salvelinus namaycush
Authors: Black Edgar C.
Published: April 2011

During the summer of 1954, 1½-year-old, hatchery-raised lake trout, Salvelinus namaycush, were subjected to 15 minutes of severe muscular exercise at the trout hatchery at Summerland, B.C. Following exercise, fish were allowed to recover for various intervals up to 24 hours. Blood samples were taken and analyzed. The hemoglobin levels did not change significantly, the blood glucose increased significantly during the second hour of recovery. Except for dips at the 6th and 12th hours, this high level of glucose persisted to the end of 24 hours. The blood level of lactic acid increased sevenfold immediately following exercise and continued to increase during the first two hours of recovery. The lactic acid level declined rapidly between the 2nd and 6th hour. The initial low unexercised level was reached by the end of 24 hours. The hemoglobin and lactic acid changes were very similar to those noted for Kamloops trout, Salmo gairdneri.
Possible Effects of Water Diversions on Fish Distribution in British Columbia
Authors: Lindsey C. C.
Published: April 2011

The known distributions of freshwater fishes in drainages of the British Columbia mainland are summarized, including those of five species not previously recorded from the province. The continental divide forms a break in fish distribution; 35 of the 57 species on the Pacific slope in B.C. do not occur in the Mackenzie or Yukon River drainages of the province, and 11 of the 33 species in the latter area occur nowhere on the Pacific slope. Some proposed water diversions for hydroelectric development would cross the continental divide, and are likely to produce striking changes in fish distribution. A proposed Liard-Stikine diversion would probably introduce several species, including trout, into the upper Liard River, and several other species, including northern pike (Esox lucius) into the Stikine River. A proposed Peace-Fraser diversion would introduce into the Fraser River arctic grayling, and possibly several other species including northern pike. Other proposed diversions are discussed, and their probable affects on fish distribution are listed. Any diversion introducing pike into waters supporting Pacific salmon (Oncorhynchus) is liable to be economically harmful, as pike are voracious fish-eaters. Pike are also vectors of Triaenophorus tape-worm, which has been found in Alaska to encyst in the flesh of Pacific salmon in a watershed inhabited by pike.
Oceanographic Features of the Canadian Archipelago
Authors: Bailey W. B.
Published: April 2011

Oceanographic data collected during the first cruise of H.M.C.S. Labrador to the Canadian Arctic in August and September 1954 permit comparisons of the vertical temperature and salinity structures in Baffin Bay, the Canadian Archipelago and the Arctic Ocean. From a comparison of the temperature–salinity characteristics of the waters in the Arctic Ocean (Beaufort Sea) with those in Baffin Bay, it is found that: (a) the surface waters of the Arctic Ocean are much less saline than those in Baffin Bay, but minimum temperatures are the same (−1.8 °C), (b) the waters of the upper 200 m. in Baffin Bay are denser than those found at corresponding depths in the Arctic Ocean, (c) below 200 m., Arctic waters are the denser, and below 500 m. they are denser than any waters found in Baffin Bay, and (d) waters found at 250 m. in the Beaufort Sea, at 500 m. in Smith Sound, and at 1250 m. in central Baffin Bay, have identical temperature and salinity characteristics (−0.3 °C., 34.4‰).In addition the data permitted limited investigations into the effect of drifting ice floes on the vertical temperature structure of the water, the origin of the "north water", long-term variations in the oceanographic conditions in Baffin Bay, and dynamic calculations of currents and volume transports of the waters through the channels leading into Baffin Bay.
The Effect of Certain Antibiotics on the Production of Trimethylamine and Hydrogen Sulphide by Bacterial Enzymes
Authors: Castell C. H. , Greenough Maxine F.
Published: April 2011

By the use of the washed cell technique it has been shown that the antibiotics chlortetracycline, oxytetracycline, polycycline and nisin in concentrations from 1 to 50 p.p.m. do not retard the bacterial reduction of trimethylamine oxide to trimethylamine. It has also been shown that chlortetracycline and oxytetracycline do not inhibit the reduction of cysteine to hydrogen sulphide by bacterial enzymes.
The Redfish (Sebastes marinus L.) in the Western Gulf of St. Lawrence
Authors: Steele D. H.
Published: April 2011

Size at maturity and meristic characters of redfish from the Gulf of St. Lawrence are intermediate between those of the Gulf of Maine and the more northern European areas. Redfish are abundant in the Laurentian Channel in the region southeast of Seven Islands, but scarce west of this. The narrow size range (33 to 41 cm.) of the large, mature redfish taken in the Gulf of St. Lawrence is due to a southerly drift of larvae away from the spawning area, to an accumulation of old, mature fish, and to a differential distribution by sizes. The last is considered to be of primary importance. The availability of redfish on the bottom shows seasonal variations and catches were largest in the autumn. Redfish feed off the bottom and the dominant food for the sampled areas was the bathypelagic euphausiid Meganyctiphanes norvegica. Smaller catches of redfish at night in bottom trawls are attributed to vertical movements.
A New Technique for Studying Non-tidal Drift with Results of Experiments off Gay Head, Mass., and in the Bay of Fundy
Authors: Bumpus Dean F. , Chase Joseph , Day C. Godfrey , Frantz Jr. David H. , Ketchum David D. , Walden Robert G.
Published: April 2011

A transponding drift buoy has been developed to aid in the study of the horizontal motions of surface waters. Experiments to study the non-tidal drift off Martha's Vineyard, Mass., in June 1956, off Yarmouth, N.S., in October and November 1956, in Grand Manan Channel in October 1956, and off Saint John, N.B., in December 1956, are described and discussed.
The Effect of the Prevailing Winds on the Inshore Water Masses of the Hecate Strait Region, B.C.
Authors: Barber F. G.
Published: April 2011

Observations show that during the winter period of strong southeast winds, light surface waters accumulate along the coast, displacing the deeper waters offshore. During the summer period of weak southeast winds the accumulated surface waters move offshore allowing the return of the deep waters.The winter accumulation is accompanied by a northwestward-flowing coastal current which appears to be continuous from California to the Gulf of Alaska. During the summer this current is small or absent.It is noted that this seasonal change of water masses accounts for a major part of the observed sea level oscillation.It is suggested that the winter displacement of deep waters and their return affect the movement of bottom fish of the region.
Circulation on the Scotian Shelf as Indicated by Drift Bottles
Authors: Trites R. W. , Banks R. E.
Published: April 2011

The surface circulation on the Scotian Shelf has been investigated by means of 827 drift bottles released by the Naval Research Establishment in August, 1954. The study suggests a cyclonic circulation centred in the vicinity of Sable Island Bank but with the eastern part incompletely determined by the results. Calculated speed of drift varies from 0.11 to 0.15 knot.