bluuebunny/crossref_metadata_2025 huggingface dataset:
Phosphatase Activity in Some Species of Marine Phytoplankters
Authors: Antia N. J. , Watt A.
Published: April 2011

Evidence has been obtained for acid phosphatase activity (on p-nitrophenyl phosphate as substrate) at pH 4.8 in cell-free extracts of Phaeodactylum tricornutum, Skeletonema costatum, Cyclotella nana, Monochrysis lutheri, Isochrysis galbana, and Dunaliella tertiolecta grown photo-autotrophically in pure culture. No alkaline phosphatase activity at pH 10.5 was observed.
Sarda lineolata (Girard), a Pacific Bonito, in the Strait of Georgia, British Columbia
Authors: Manzer J. I.
Published: April 2011

not available
Estimates of the Theoretical Biomass of Juvenile Winter Flounder, Pseudopleuronectes americanus (Walbaum) Required for a Fishery in Rhode Island
Authors: Saila Saul B. , Horton Donald B. , Berry Richard J.
Published: April 2011

A model of the life history of the winter flounder was constructed using empirical estimates of vital statistics. The initial stock weight of juveniles was determined by substituting trial initial stock weight values into equations which contained average values of growth and mortality coefficients until the observed value of the equilibrium yield was approximated. Model data indicated that the stock weight of juvenile winter flounder at an age of 5 months constituted a significant proportion of the equilibrium yield even with conservative estimates of model coefficients. Growth appeared to be sufficiently rapid during early life-history stages to provide for a large increase in biomass in spite of considerable natural mortality.
Records of Mollusca from the Northwest Atlantic Obtained by Canadian Fishery Research Vessels, 1946–61
Authors: Allen J. A.
Published: April 2011

In the course of investigations into the fish and shrimp resources of an area from the southern edge of the Grand Bank and the Gulf of St. Lawrence to Cape Dyer, Baffin Island, numbers of Mollusca were taken. Commercial trawls were used for the great majority of the hauls and because of mesh selection most of the Mollusca taken were specimens of the larger species. The majority of the 45 species collected are well known and the value of the present list lies in the records of distribution from an area where climatic conditions have severely restricted past sampling endeavour.
Limnological Features of Cedar Lake, Manitoba
Authors: Webb D. W.
Published: April 2011

Cedar Lake, largest lake in the Saskatchewan River system, was studied from June 14 until August 31, 1962. Twenty stations, located in the main basin of the lake, were examined during six sampling periods. These stations were located along five transects, at depths of 1.5, 3, 6, and 9 m. No thermal stratification occurred and the oxygen concentration never fell below 78% of air saturation. Total alkalinity and total dissolved solids averaged above 65 and 270 ppm, respectively.The average number of bottom organisms increased with depth, with the bulk of these being made up of spheariid clams, mayflies, chironomids, and gastropods. The number of genera also increased with depth. The standing crops determined for the six sampling periods ranged from 17.7 to 33.2 lb/acre (dry weight), with a mean value of 23.4 lb/acre. Correlations between the physical and chemical factors and the distribution of bottom fauna are examined and it is felt that the bottom type is the major factor affecting the distribution and abundance of bottom organisms in Cedar Lake. On the basis of the physical and chemical criteria, Cedar Lake may be classified as eutrophic.
Growth and Morphometry of Four British Columbia Populations of Pygmy Whitefish (Prosopium coulteri)
Authors: McCart P.
Published: April 2011

A comparison is made of the growth, morphometry, age at maturity, food, and depth distribution of pygmy whitefish (Prosopium coulteri) in four British Columbia lakes. In Tacheeda and Cluculz Lakes where the species is of the usual dwarfed variety, the fish exists sympatrically with two other whitefishes, the mountain whitefish (Prosopium williamsoni) and the lake whitefish (Coregonus clupeaformis). These slow-growing pygmy whitefish differ markedly in morphometry and depth distribution from the "giant" pygmy whitefish of McLeese and Maclure Lakes which live in the absence of other whitefishes. The possibility that differences in the populations might be due to interspecific competition is discussed.
A Record of the Hatchetfish, Polyipnus asteroides Schultz, from the Canadian Atlantic Region
Authors: Scott W. B.
Published: April 2011

not available
Description of the Postlarvae of the Sand Lance (Ammodytes) from the East Coast of North America
Authors: Richards Sarah W.
Published: April 2011

not available
A Survey of the Distribution of Intertidal Algae Along a Coast Transitional in Respect to Salinity and Tidal Factors
Authors: Widdowson Thomas B.
Published: April 2011

The dominant intertidal organisms studied in this survey were mostly brown, red, and green algae, together with a few species of marine flowering plants, barnacles, and molluscs. The flora of the northern shores of Juan de Fuca Strait show a transition between the flora of the open coast around Port Renfrew in the west, and that of the semi-sheltered coast near Victoria in the east.The differences between the flora of Port Renfrew and that of Victoria can be studied as boundaries; the eastern boundaries of species occurring at Port Renfrew but not at Victoria, and the western boundaries of species occurring at Victoria but not at Port Renfrew. Fourteen eastern (inner) boundaries of open coast organisms, and four western (outer) boundaries of sheltered coast forms were found to be concentrated in the vicinities of Port Renfrew, Victoria, and Sooke, half way between.Along Juan de Fuca Strait, Port Renfrew is the easternmost locality with a completely open coast environment, characterized by a salinity usually above 32‰. Sooke is the easternmost locality where water of 32‰ is found with some degree of frequency, probably as a result of upwelling associated with strong westerly winds. Victoria is the outermost locality where water of appreciably less than 30‰ may occur, because of heavy runoff from the Fraser River.The author studied the vertical distributions of organisms by measuring upper and lower limits at 34 stations along the coast, plotting the heights obtained, and calculating regression lines for the points plotted. These limits were of four types: A. very variable along the whole coast; B. more variable between Port Renfrew and Sooke than between Sooke and Victoria; C. slightly variable, with a slope down from Port Renfrew to Victoria; and D. slightly variable, with little or no slope.The slightly variable limits (C and D above) were used as a test of the theory that tidal factors can be used to explain, or at least describe, the vertical limits of intertidal organisms. The coast between Port Renfrew and Victoria shows a transition between a mixed semi-diurnal tide in the west and a diurnal tide in the east. Thus, the heights of the various tidal factors are usually different at Port Renfrew, Sooke, and Victoria, because of the different nature of the tides. The heights of most limits failed to correspond to the same tidal factor at these three places. The different patterns of variation and slope, found in the limits generally, indicate that it is unlikely that any other theory can provide a simple explanation of the height of most intertidal limits.
Supplementary Checks on the Scales of Pink Salmon (Oncorhynchus gorbuscha) and Chum Salmon (O. keta)
Authors: Bilton H. T. , Ricker W. E.
Published: April 2011

Among 159 central British Columbia pink salmon that had been marked by removal of two fins as fry and had been recovered in commercial fisheries after one winter in the sea, the scales of about one-third showed a supplementary or "false" check near the centre of the scale, in addition to the single clear-cut annulus. This evidence from fish of known age confirms the prevailing opinion that such extra checks do not represent annuli, hence that the fish bearing them are in their second year of life rather than their third. Unmarked pink salmon from the same area, and some from southern British Columbia, had a generally similar incidence of supplementary checks. In both marked and unmarked fish the supplementary checks varied in distinctness from faint to quite clear. In a sample of scales of 14 double-fin marked chum salmon which were known to be in their 4th year, all fish had the expected 3 annuli, and 12 fish had a supplementary check inside the first annulus.
The Relation of Size to Rate of Oxygen Consumption and Sustained Swimming Speed of Sockeye Salmon (Oncorhynchus nerka)
Authors: Brett J. R.
Published: April 2011

The relation of size (log weight, g) to metabolic rate (log O2-uptake, mg O2/hr) of sockeye salmon was found to have a continuous change in slope (0.78–0.97) with increasing activity at 15 C.The slope of the equation relating the 60-min sustained swimming speed (log speed, cm/sec) to length (cm) had a value of 0.50, demonstrating a rapid decrease in relative performance with increasing size.
New Size Record for Greysole (Glyptocephalus cynoglossus)
Authors: Powles P. M.
Published: April 2011

not available
Lecithinase Activity in the Muscle of Rainbow Trout (Salmo gairdnerii)
Authors: Bilinski E. , Jonas R. E. E.
Published: April 2011

A radioactive tracer procedure for determination of the various lecithin hydrolysing enzymes, at a low level of activity, is described. The procedure involves the use of phospholipids labeled with C14in the choline moiety as substrate and the measurement of radioactivity released in the various products of hydrolysis. The pathway of lecithin catabolism in trout muscle is via glycerylphosphorylcholine. Of the other possible routes of breakdown of lecithin, there was no indication for the activity of phospholipase C or D. Greater enzymic activity was present in the lateral line muscle than in the white muscle. The enzyme which is responsible for hydrolysis of lecithin to glycerylphosphorylcholine showed optimum activity in the vicinity of pH 7 did not require Ca++for activity and was partially inhibited by Hg++. A lysolecithinase, showing similar properties, but having a comparatively greater activity, was also present in trout muscle.
Influence of Temperature, Salinity, and Photoperiod on the Aggregations of Chum Salmon Fry (Oncorhynchus keta)
Authors: Shelbourn J. E.
Published: April 2011

Underyearling chum fry from hatchery stock were held in fresh water and salt water at two different temperatures and under two different photoperiods and acclimated to these conditions for 40 days before testing started. Aggregations were greater in salt water than in fresh water (p <.01). Fish acclimated to cold water schooled more strongly than those acclimated to warm water but this effect was not considered statistically significant. There were no differences in intensity of aggregation due to photoperiod (p >.05). The significance of these findings is discussed in relation to life history of the fry.
Glycogenolytic Enzymes of Cod (Gadus callarias) Muscle
Authors: Burt J. R.
Published: April 2011

Some properties of the enzymes amylase, phosphorylase, and phosphoglucomutase in homogenates of cod muscle have been investigated. Amylase is activated by a short period of autolysis and by chloride ions; hydrolyses cod muscle glycogen at about half the rate it hydrolyses mussel glycogen; has an optimum temperature of 52 C for up to 5 hr incubation; and has a wide range of activity with maxima around pH 5.1 and between pH. 7.0 and 7.5. Using phloridzin, an estimate of the relative importance of hydrolytic and phosphorolytic cleavage of polysaccharide in cod muscle homogenates has been made. Phosphorylase shows two activity maxima at pH 5.5 and 6.7. The properties of phosphoglucomutase, with the exception of its pH activity, in cod muscle are similar to those reported for this enzyme in other tissues. Cod muscle phosphoglucomutase has maximum activity between pH 8 and 9.
Distribution and Speciation of Iron in Natural Waters: Transition from River Water to a Marine Environment, British Columbia, Canada
Authors: Williams P. M. , Chan K. S.
Published: April 2011

Total and "HCl reactive" iron has been determined for particulate and soluble forms in freshwater and seawater samples along a profile extending from Hope, British Columbia, 100 miles up the Fraser River, to a station in the Northeast Pacific Ocean, 60 miles west of Cape Flattery, Washington. Complementary data were taken on salinity, dissolved oxygen, pH, and temperature. Observations covered periods of high and low river runoff from June 1962 to June 1963.Total particulate iron concentrations in the Fraser River were highest during the maximum runoff period in summer, while total soluble iron concentrations did not significantly increase at this time. Admixture of saline water with fresh water at the river mouth caused the expected abrupt decrease in particulate iron below the upper 2 m.Both the total particulate and total soluble iron concentrations in seawater samples decreased from the Strait of Georgia seaward through Juan de Fuca Strait out into the Pacific Ocean. In summer, the total soluble iron was higher than in winter while the total particulate iron was lower. The seasonal fluctuations of the sum of the total particulate and total soluble iron were not significant.The high amounts of the soluble forms of iron and the concurrent low particulate iron concentrations in summer may be partially explained by the assimilation of particulate iron during periods of high phytoplankton productivity, mainly by diatoms, with release of soluble forms during lysis of these organisms.The mean annual total iron discharged by the Fraser River was 1.90 × 105 kg/day, the bulk of which was immediately laid down in the river delta.There was no evident correlation of the iron distribution with that of pH, oxygen, or density, excepting in the region immediately adjacent to the mouth of the Fraser River.
Maturation and Fecundity of Brook Trout from Infertile Streams
Authors: Wydoski Richard S. , Cooper Edwin L.
Published: April 2011

The reproductive rate of brook trout populations from infertile Pennsylvania streams was determined. The standing crops for eight streams varied between 14 and 41 lb/acre. Trout in age-groups 0 through III were found to grow slowly with very few individuals reaching a total length of 6 inches.The seasonal development of ova was determined by measuring all ova larger than 0.2 mm from selected females. The maturing ova of most females of age-groups II and III increased in diameter from 0.9 mm in February to 1.0 mm in June, 1.75 mm in July, 2.5 mm in August, 3.0 mm in September, and 4.0 mm in October. Maturing females could be distinguished from immature females by late August or early September on the basis of ova diameters. The mean diameter of ripe ova from 67 females was 4.05 mm with a range between 3.37 and 5.01 mm for individual trout ranging from 4.6 to 8.6 inches total length.The relationship between the number of mature ova and the total length of the female for one population was described by a curvilinear regression (log Y = −0.5361 + 3.23 log X, where Y = number of eggs, and X = the total length of the fish) for brook trout between 3.6 inches (18 eggs) and 7.7 inches (213 eggs). Variation in this relationship existed among streams.Ova production was estimated as 9050 ova per acre for one population and 13,620 ova per acre for another. Age-group-I females contributed approximately 9% of this production; age-group-II females, 54%; and age-group-III females, 37%. An ecological life table was constructed for two populations comparing rates of survival, age-specific fecundity rates, and reproductive rates.
Depensatory Process Based on the Concept of Hunger
Authors: Junge Charles O.
Published: April 2011

In a recent paper by Larkin et al. (1964) reproduction curves are considered for life history stanzas, and a depensatory process related in form to the compensatory process of Ricker (1954) is presented. In the following development the necessity of defining such functions as two parameter systems is presented. A theoretical production curve based on the concept of hunger is derived. It is also shown that under conditions of extreme predation this curve approximates Larkin's depensatory production curve. The curve is applied to data for Adams River sockeye salmon.
New Methods for Reducing the Toxicity of Kraft Mill Bleachery Wastes to Young Salmon
Authors: Betts J. L. , Wilson G. G.
Published: April 2011

Kraft pulp mill bleachery effluents and those from the unbleached screening operation were tested, separately and in combination in the proportions as they would exist in the main effluent of a particular mill, for toxicity to young Atlantic salmon, Salmo salar.The bleachery component from the chlorination stage, tested under neutral pH conditions, was considerably more toxic than the other components.Major reductions in the toxicity of the chlorination stage component were accomplished by treating it with small quantities of sulphur dioxide. Lesser but still appreciable toxicity reductions were observed in the whole effluent when the chlorination component was thus treated before combination with the other components.The toxicities of laboratory-produced filtrates from certain modified first-stage (chlorination) bleaching procedures were also evaluated. Notably, much less toxic filtrates resulted when substantial mixtures of chlorine dioxide and chlorine were substituted for the normal chlorine dosage in the first bleaching stage.A number of other treatments, methods, and their relative effectiveness are discussed.
Vitamins B in Dulse (Rhodymenia palmata)
Authors: Kanazawa Akio , Saito Akira , Idler D. R.
Published: April 2011

not available
Micro Starch Gel Electrophoresis
Authors: Tsuyuki H. , Roberts E. , Kerr R. H. , Ronald A. P.
Published: April 2011

not available
Resistance to Zinc Sulphate of Zebrafish (Brachydanio rerio) Embryos After Removal or Rupture of the Outer Egg Membrane
Authors: Skidmore J. F.
Published: April 2011

Fifteen- and 25-hr-old zebrafish (Brachydanio rerio Hamilton-Buchanan) embryos with the outer egg membrane ruptured survived longer in a solution of zinc sulphate (20 ppm Zn) than embryos of the same ages with the membrane intact. Forty-two-hour embryos with the membrane completely removed survived in four concentrations of zinc sulphate (2.5, 5, 10, and 20 ppm Zn) at least as long as 42-hr embryos with the membrane entire. The high resistance of zebrafish embryos to zinc was therefore not owing to protection by the membrane. On the contrary the presence of the membrane lowered resistance.This result was probably owing to the formation of opaque material enclosed by the outer egg membrane of zinc-poisoned, unruptured eggs. The action of this material in reducing survival is unknown.
Deck Sampling of Research Vessel Catches
Authors: May A. W. , Hodder V. M.
Published: April 2011

not available
A Portable Press for Making Impressions of Salmon Scales
Authors: Jenkinson D. W. , Sutherland K.
Published: April 2011

not available
First Record of Pyrgopsis lemur (Cephalopoda; Cranchiidae) from the Northwest Atlantic
Authors: Mercer M. C.
Published: April 2011

not available
Feeding, Growth, Respiration, and Carbon Utilization of a Euphausiid Crustacean
Authors: Lasker Reuben
Published: April 2011

In the euphausiid shrimp Euphausia pacifica, a member of the oceanic plankton, growth was as rapid as 0.048 mm/day in juveniles in the laboratory, more than twice as fast as that observed for oceanic populations (0.02 mm/day) by other workers. Periods between molting, which occurs throughout the life span, varied between 3 and 8 days depending on the temperature but not on the amount of food eaten. Respiration accounted for the major portion of the assimilation of carbon (62–87%) and molting, growth, and reproduction accounted for the remainder. In mature animals, 9% of the assimilated carbon was released as the organic portion of the eggs. Rapidly growing animals incorporated as much as 30% of the assimilated carbon, but calculations for an oceanic population gave 9% as the incorporation of organic carbon into tissue (excluding eggs and molts) over the life span of the animal. Assimilation of ingested carbon (digestion) appeared to be high, usually over 80%, as judged from tracer experiments. In the laboratory, crustacean nauplii seemed to be a preferred food over unicellular algae but both were eaten when available; one alga was rejected. Nauplii must be smaller than 0.8 mm for many to be ingested by adult E. pacifica. Molting, which mainly occurred at night, depressed feeding. The filtering rates for the animal on unicellular algae are sufficient for growth and metabolism if the carbon available to the animal in the sea is equivalent to that contributed by both detritus and phytoplankton standing crop in the area of the northeastern Pacific Ocean where E. pacifica is found. It is suggested that adult E. pacifica must capture between 100 and 200 nauplii per day as 1-year-olds and 200–300 per day as 2-year-olds to satisfy all of its carbon requirements. The mean density of small crustaceans in nature is probably too low for this animal to fulfill its needs. However, concentrations may be high enough in local aggregations.
Microorganisms Isolated from the Hemolymph of the Lobster (Homarus americanus)
Authors: Cornick John W. , Stewart James E.
Published: April 2011

not available
Lepomis megalotis, the Longear Sunfish, in Western Ontario
Authors: Gruchy C. G. , Scott W. B.
Published: April 2011

not available
Northern Range Extensions for Three Species of Rockfish (Sebastodes flavidus, S. paucispinis, and S. pinniger) in the North Pacific Ocean
Authors: Westrheim S. J.
Published: April 2011

not available
Some Methods for Estimating Exploited Populations
Authors: Allen K. Radway
Published: April 2011

Three methods of estimating population and one of estimating recruitment are described which are suitable for use where data are available on annual age composition, the numbers caught, and the effort expended in taking a known part of the catch.The recruitment rate is estimated, as the proportion of new recruits in the recruited population, from age composition data year by year without regard to the sizes of the parent populations, and from the approximate fishing mortality rate.The "q" population method estimates q, the coefficient of catchability, by comparing the rate of disappearance of a fixed group of year-classes with the rate of accumulation of fishing effort, using the rate of disappearance with age in a similar, unexploited population to eliminate the effects of natural mortality. The annual populations are then estimated from q and the catch per unit effort.The natural mortality and reproduction method is basically a modification of the DeLury method with an allowance for natural reproduction and recruitment. It obtains a series of estimates of the base year population by considering each of the periods beginning in this year and ending in each successive subsequent year, the final estimate being the mean of this series.The expected catch method takes as unknowns the initial population and the value of q, estimates the expected catches in each year, and compares them with the actual catches. It determines the values of the initial population and q which minimize the sum of the squares of the differences.Examples are worked out in full for all methods.
Erroneous Thiobarbituric Acid Values in Fish Tissues Caused by Their Normal Content of Free Iron
Authors: Castell C. H. , Boyce G. A.
Published: April 2011

Erroneously high TBA values were obtained from liver, dark muscle, and certain other organs taken from seven species of sea fish. This error was eliminated by carrying out a portion of the test under anaerobic conditions or, more simply, by adding a mixture of EDTA and propyl gallate to the tissues immediately before the test is carried out. The error in the TBA values from the white muscle of lean fish and from whole cod fillets was found to be extremely small.By adding measured amounts of iron to white muscle immediately before testing it was found that from 1 to 20 ppm Fe++was sufficient to cause extensive errors in the TBA values. Schoenmakers and Tarladgis have recently reported that up to 5000 ppm Fe+++can be added to methyl linolenate and several vegetable oils without changing the TBA values. It is suggested that this apparent contradiction is the result of the differences in the substrates used. Marine oils contain more highly unsaturated fatty acids and the tissues contain other biologically active compounds capable of reacting with the oxidizing lipids.
Feeding and Growth of Redfish (Genus Sebastes) in Captivity
Authors: Kohler A. C.
Published: April 2011

not available
Efficiencies of the Net Plankton and the Centrifuged Seston Methods in Highly Eutrophic Lakes
Authors: Kerekes Joseph
Published: April 2011

not available
New Speed Calibration Curves for the Braincon Type 316 Histogram Current Meter
Authors: Carrothers P. J. G.
Published: April 2011

not available
Meristic Numbers of Yellow Perch in Saline Lakes in Manitoba
Authors: Driver E. A. , Garside E. T.
Published: April 2011

not available
Northern Range Extension Record for the Pygmy Rockfish (Sebastodes wilsoni)
Authors: Harling W. R.
Published: April 2011

not available
Redescription of a North Pacific Prickleback, Alectridium auranticum
Authors: Peden Alex E.
Published: April 2011

Alectridium auranticum Gilbert and Burke, which was previously known from a single specimen and synonymized with Alectrias alectrolophus (Pallas), is redescribed. Many new specimens indicate that the species is readily distinguishable from the other members of the stichaeid subfamily Alectriinae by a single median interorbital head pore and the scales on the body not extending in front of the 13th anal fin ray. It is found in the lower intertidal and subtidal waters between the Commander Islands, USSR, and Kodiak, Alaska.
Preservation of Fresh Whitefish with Gamma Radiation
Authors: Ostovar K. , Slusar M. , Vaisey M.
Published: April 2011

This paper is an outline of a recent study which shows that the storage life of fresh whitefish (Coregonus clupeaformis) is extended considerably by the low levels of gamma radiation. On the basis of bacteriological and sensory evaluations, a dose of 150,000 rads proved to be the most effective treatment; the samples exposed to this level of radiation were judged acceptable up to 29 days of storage in ice. Fish treated with 75,000 rads were acceptable up to 22 days whereas those treated with 300,000 rads, though bacteriologically acceptable, received lower sensory scores throughout the experiment.Bacteriological studies showed that unirradiated fresh samples were dominated by Gram-negative microorganisms belonging to the genera Pseudomonas, Achromobacter, and Flavobacterium. Samples treated with 150,000 rads showed survival of Gram-positive microorganisms belonging to the genera Corynebacterium and Micrococcus which were replaced by Gram-negative microorganisms after 29 days of storage.
Effects of Feeding on the Thyroid, Kidney, and Pancreas in Sexually Ripening Adult Sockeye Salmon (Oncorhyncus nerka)
Authors: McBride J. R.
Published: April 2011

In unfed adult sockeye salmon, Oncorhynchus nerka, histological examination showed extensive degenerative changes in the thyroid, pancreas, and kidney during gonad development. The more pronounced changes were generally noted in starved fish spawned in the wild. Feeding either prevented (thyroid) or distinctly reduced (pancreas, kidney) these changes in the sexually ripe fish. In fed spent sockeye the thyroid showed little change, the kidney exhibited further deterioration although not as marked as in the corresponding unfed fish, but the pancreas showed marked degenerative changes comparable with those exhibited in the unfed.
Relationship of Temperature to Total Annual Growth in Adult Smallmouth Bass
Authors: Coble Daniel W.
Published: April 2011

Total yearly growth of smallmouth bass, Micropterus dolomieui Lacépède, of ages 3–5 in South Bay, Lake Huron, and in several other widely scattered populations was related to mean surface water temperature for the period July through September, more growth being associated with warmer waters. No such relationship was demonstrated for bass of the same ages in Lake Opeongo, Ontario, nor for older bass in Lake Opeongo and South Bay. The difference in the manifestation of a growth–temperature relationship appears to be real, rather than a result of differences in data or treatments of them, and indicates, therefore, that other factors may influence total annual growth as much as, or more than, temperature.
Factors Affecting the Response of Trout to an Electric Field in Fresh and Salt Water
Authors: Flux John E. C.
Published: April 2011

The "minimum response" level of Salmo trutta to an alternating current field increased with angle to the field, temperature, resistivity, and fatigue, with a wide range of individual variation. The drop in potential across the length of a fish ("body-voltage") varies directly with length and is not a constant for the species in either fresh or salt water. Embryo trout show a fully developed response 2 weeks after hatching.
Atlantic wolffish (Anarhichas lupus L.) eggs off southern Nova Scotia
Authors: Powles P. M.
Published: April 2011

not available
The Sodium, Potassium, and Water Content of the Flesh of Sockeye Salmon (Oncorhynchus nerka) in Relation to Sexual Development and Starvation
Authors: Tomlinson N. , McBride J. R. , Geiger S. E.
Published: April 2011

The influence of feeding on the changes that occur in the skeletal muscle content of sodium, potassium, and water in sockeye salmon (Oncorhynchus nerka) during sexual development and spawning has been investigated. Feeding has little, if any, effect on the changes. Thus it appears that the period of starvation these fish undergo during their spawning migration under natural conditions is not the major cause of the degeneration of their skeletal muscle, but rather that these changes are associated in some manner with the development of the gonads, presumably through the mediation of hormones.
A Generalized Computer Program For the Ricker Model of Equilibrium Yield Per Recruitment
Authors: Paulik G. J. , Bayliff William H.
Published: April 2011

The Ricker method for predicting the yield per recruitment from a stock of fish under various conditions is superior to that of Beverton and Holt (1957) under most conditions because it permits greater flexibility of the input of growth and mortality data. Such useful devices as the isopleth diagram and the eumetric fishing curve, usually associated with the Beverton and Holt method, can be used also with the Ricker method. A computer program for the Ricker method is described, and its use is demonstrated with an example.
Estimation of Marine-Borer Attack on Wooden Surfaces
Authors: Walden C. C. , Allen I. V. F. , Trussell P. C.
Published: April 2011

Bankia setacea prefer to attack upper horizontal wooden surfaces, whereas Limnoria spp. prefer the lower surfaces. Attack by B. setacea is heaviest at the mudline and decreases almost linearly with decreasing depth. Limnorial attack is heaviest in the intertidal zone, then is relatively constant with increasing depth. Statistical studies showed non-normal distribution of populations, with limited replicability, particularly for low Bankia counts. The desirable period of immersion is greater than 2 weeks, but in most commercial monitoring situations is limited to 1 month. Attack data on immersion specimens are compared with those on floating logs. On the basis of the results, procedures have been designed for monitoring attack in the commercial evaluation of impregnants, as well as for estimating population densities.
Returns of Hatchery-Reared Lake Trout in Southern Lake Superior, 1955–62
Authors: Pycha Richard L. , King George R.
Published: April 2011

Experimental plantings of fin-clipped lake trout (Salvelinus namaycush) of various ages have been made in southern Lake Superior since 1952. The catch of planted lake trout by the commercial fishery was used to measure the success of stocking. Estimates of total returns were based on samples of 8.2 to 21.2% of the Wisconsin catches in 1955–62 and 36.4 to 46.8% of the Michigan catches in 1959–62. Marked lake trout were assigned to various plantings according to the fin mark, length of fish, readings of age from scales, and locations of capture.Estimated returns from Wisconsin plantings of 9-month-old lake trout varied from 2.1 to 6.4%. Wisconsin releases of 16-month-old fish yielded returns of 5.7 to 37.3%. Returns from plantings in Michigan were 0.3% for 9-month-old fish and 1.5 to 3.8% for 16-month-old fish. The ratios of the returns from plantings of 16-month-old fish to those of 9-month-old fish were 3.9:1 for Wisconsin releases and 6.7:1 for Michigan releases. Lake trout planted in Wisconsin generally survived better than those released in Michigan. Returns from fish planted at ages of 17 to 40 months in Michigan in 1958–59 were far greater than those from 16-month-old fish released in Michigan, but were not as high as from the most successful plantings of 16-month-old fish in Wisconsin. Lake trout released in 1960 from shore and from boats survived equally well.Average size of lake trout at release was more closely related to survival than any other factor. All except 1 of 10 highly successful releases were of fish larger than 22 per lb, and all 6 poor releases were of fish smaller than 34 per lb. Fish that ran 22 to 33 per lb survived only moderately well. A size of 17 to 20 fish per lb appears to be close to optimum.Abundance of native lake trout, American smelt (Osmerus mordax), and sea lampreys (Petromyzon marinus) all appeared to be unrelated to stocking success. The only apparent method of rapidly improving the success of stocking is to rear all lake trout to an average size of 17 to 20 per lb.
Lethal Endrin Concentration in the Blood of Gizzard Shad
Authors: Brungs W. A. , Mount D. I.
Published: April 2011

not available
Seasonal Changes in Fatty Acid Composition of Cod Liver, Flesh, Roe, and Milt Lipids
Authors: Jangaard P. M. , Ackman R. G. , Sipos J. C.
Published: April 2011

The fatty acid compositions of lipids from an isolated population of inshore cod (Gadus morhua L.) caught near Terence Bay, Nova Scotia, were determined each month on pooled samples of representative fish. Cod liver oil was studied over a period of 17 months, cod flesh for 12 months with the fatty acid compositions of milt, roe, flesh, and liver lipids being determined from some large, individual fish.The fatty acids of flesh lipids were independent of sex and showed very little, if any, seasonal changes except a slight variation in the long-chain monounsaturated acid 20:1 (max 2.8% vs. avg 1.6% and 1.1%). This was especially evident in large fish where the maximum (3.7%) coincided with the period of best "condition," August to November. There was also a significant difference between large and medium size fish in that in very large fish the content of 22:6 was much lower (26% vs. 33%). Liver oils in female fish contained increasing amounts of 20:1 (4.5 to 14.9%) and 22:1 (1.8 to 12.3%) fatty acids with increased fat content of the liver, maxima occurring in late summer and fall. In the male fish this seasonal trend was not as obvious. No other acids showed any definite seasonal variation. In the fatty acids of roe and milt lipid no definite relationship could be established between ripening and fatty acid composition. The fatty acids of the milt were similar to the roe except for a higher percentage of 18:1 and lower percentage of 16:1. The unsaponifiable matter was higher in milt than in roe lipids.These results indicate that due to the large variations that can occur in the fatty acid content of lipids from individual fish, a single analysis could give a fatty acid composition quite different from the average of a large number of determinations.
A Shrimp Pot for Experimental Fishing
Authors: McBride Roland , Barr Louis
Published: April 2011

not available
Prespawning Adult Salmon Mortality Associated with a Fungus of the Genus Dermocystidium
Authors: Pauley Gilbert B.
Published: April 2011

A serious outbreak of mortalities occurred among adult salmon held in the Priest Rapids Dam spawning channel in November 1965. Gross examination revealed small, white cysts on and in the gill filaments of otherwise normal-appearing fish. Approximately 25% of the 5000 mature adult salmon in the channel died prior to spawning from this disease caused by a fungus identified as the genus Dermocystidium. This is the first record of an epidemic among fish of North America associated with Dermocystidium. The primary cause of death appeared to be anoxia due to subacute inflammation and granulation of the gill tissue. A description of the histopathology associated with these parasites is given. Chondrococcus columnaris, a pathogen of warm-water fishes, was present as a secondary invader on the gill filaments of several salmon and an unknown fungal or yeast-like organism was present in the testes of the male fish examined.
Marking Pacific Salmon with Tetracycline Antibiotics
Authors: Weber Douglas , Ridgway George J.
Published: April 2011

Diets containing tetracycline antibiotics were fed to hatchery populations of Pacific salmon. Subsequent examination of bone samples from these populations indicates that the tetracyclines are deposited permanently in the skeletal structure, are readily detectable after a period of rapid growth, and do not affect growth or survival. The most satisfactory and consistent marks were obtained by feeding 250 mg of tetracycline antibiotic per kilogram of body weight per day for 4 consecutive days.
Effect of a Partial Loss of Scales and Mucous on Carbohydrate Metabolism in Rainbow Trout (Salmo gairdneri)
Authors: Black Edgar C. , Tredwell S. J.
Published: April 2011

This study was undertaken to determine what part partial scaling and partial desliming might play in the survival of trout. Carbohydrate metabolism in these trout was studied and in addition, hemoglobin levels and red cell volumes were studied to serve as indicators of osmotic shifts of water.Increases in lactate were minimal and occurred during the first few hours of holding after the removal of [Formula: see text] to [Formula: see text] of the scales. There were slight changes in hemoglobin levels and red cell volumes which appeared to coincide with activity as reflected by lactate levels. There was a three- to fourfold increase in the blood glucose level of partially scaled fish. Liver glycogen levels dropped to [Formula: see text] of the air-dipped control value for fish that had been [Formula: see text] scaled and held in holding baskets for a period of 140 hr. Only one mortality occurred in all the experiments.The following conclusions were reached. Partial loss of scales or mucous does not result in the death of rainbow trout (Salmo gairdneri). Partial scaling or desliming of the fish was accompanied by a significant increase in blood glucose (p < 0.05).
Pyloric Caeca and Gill Raker Development in Lake Trout, Salvelinus namaycush, in Algonquin Park, Ontario
Authors: Martin N. V. , Sandercock F. K.
Published: April 2011

Counts of pyloric caeca and gill rakers were made on lake trout (Salvelinus namaycush) in three Algonquin Park lakes where the trout were dependent on plankton for food in varying degrees. In 798 trout from the three lakes, pyloric caeca counts ranged from 105 to 210 and varied with the size of trout. There was no association between numbers of caeca and type of food eaten.Gill raker counts were made on 930 lake trout. Numbers of rakers are not related to size or sex of lake trout in the sample. Gill raker counts ranged from 17 to 26 in the combined populations. An association exists between the numbers of gill rakers, their length, and the amount of plankton eaten by the lake trout. Accessory gill rakers on the medial surface of the gill arch are described. The number and development of these rakers were associated with the amount of plankton eaten by the lake trout.
Contributions of Year-Classes of Blue Pike to the Commercial Fishery of Lake Erie, 1943–59
Authors: Parsons John W.
Published: April 2011

The blue pike (Stizostedion vitreum glaucum) contributed about 12.7 million lb annually to the commercial production of fish in Lake Erie in 1915–59. Production averaged about 27% of the total for all species; in some years it exceeded 50%. The catch fluctuated greatly and was featured by a series of seven "highs" and "lows" during the 45-year period. The landings ranged between 2 million and 26 million lb; periods of peak production were 5 to 9 years apart. A sharp decline in the catch started in 1957. The take of 79,000 lb in 1959 was the lowest on record to that time.Age and size compositions of the catch were determined from samples of blue pike taken from commercial landings in the fall, 1943–59. Peaks in production in that period were attributed to a few strong year-classes separated by several weak year-classes. Of the 20 year-classes represented in the samples, those of 1944 and 1949 were by far the strongest; together they contributed 42% (by weight) of the fall blue pike production in 1943–59. The strength of the 1939 and 1940 year-classes was moderate and the 1954 year-class was the last one of any importance. The other 15 year-classes were weak.The 1957–59 decline in production was accompanied by a marked increase in rate of growth. Blue pike in age-group III weighed nearly eight times more and were 7.7 inches longer in 1959 than in 1951. Landings after 1958 consisted of only a few large fish. The collapse of the fishery forced blue pike fishermen either to fish for less valuable species or to discontinue operation.
The Gempylid Nealotus tripes New to the Canadian Atlantic
Authors: Beckett J. S. , Barrett B. E.
Published: April 2011

not available
Freshwater Fish Oils: Yields and Composition of Oils from Reduction of Sheepshead, Tullibee, Maria, and Alewife
Authors: Ackman R. G. , Eaton C. A. , Bligh E. G. , Lantz A. W.
Published: April 2011

Oils were produced from four species of freshwater fish (sheepshead, Aplodinotus grunniens; tullibee, Coregonus artedii; maria, Lota lota; alewife, Alosa pseudoharengus) in a commercial reduction plant. The oil iodine values were, respectively, 123, 143, 158, and 165. Fatty acids were determined by gas–liquid chromatography. All four oils showed higher levels of C16 and C18 fatty acids than corresponding marine oils, but only sheepshead and tullibee had distinctly low levels of C22 acids. The four freshwater oils differed from most marine oils in having higher proportions of linoleic, linolenic, and arachidonic acids. In most respects fatty acid compositions of freshwater fish oils were not dissimilar from marine oils.
The Cranial Osteology of the Gadidae
Authors: Mujib Khwaja Abdul
Published: April 2011

The cranial skeletons of four gadid fishes, Gadus morhua (subfamily Gadinae), Urophysis chuss (Lotinae), Lota lota (Lotinae), and Merluccius bilinearis (Merluccinae), are described in detail.The Merluccinae probably gave rise, on one hand, to the subfamily Lotinae and, on the other, to the subfamily Gadinae; both of these subfamilies became further specialized. All three subfamilies differ from each other in their cranial osteology, as well as in other characters.
Freeze-drying of Atlantic Cod Steaks
Authors: Legendre R. , Wood A. L.
Published: April 2011

A preliminary study was made of the freeze-drying of steaks 6–18 mm thick, at sample temperatures from 38 to 98 C and under total dryer pressures from 20 to 2000 μ, from pre- and postrigor, quick- and slow-frozen cod. The drying time varied directly with the thickness, inversely with the temperature of the sample, was not affected by total pressure within the dryer with the thinner samples, but appeared to vary inversely with pressure for those 12 mm thick. Total drying time was the same for 16-mm thick samples from pre- or postrigor, quick- or slow-frozen fish, but varied with 6-mm thick steaks.Evaluation of quality varied inversely with both thickness and temperature but was not affected by dryer pressure. Only the postrigor, slow-frozen samples were consistently below the quality level of consumer acceptance.
Fecundity of Atlantic Cod
Authors: May A. W.
Published: April 2011

Fecundity of Atlantic cod from the Newfoundland and Labrador area was investigated in relation to fish length, weight, and age. Variations in fecundity were best explained in terms of size, either length or weight. The fecundity–length relationship was adequately described by the simple allometry formula; fecundity–weight by an arithmetic straight line. Differences in fecundity from north to south are described and discussed in relation to descriptions from other areas. Substantial differences in fecundity of western and eastern Atlantic cod are noted.
Use of Standardized Colour Surfaces in the Grading of Canned Salmon for Colour
Authors: Bolton R. S. , Mann J. H. , Gushue W.
Published: April 2011

not available
Preparation of Light-Salted Fish by Brining
Authors: Legendre R.
Published: April 2011

Kench and pickle salting are being used for the preparation of both light- and heavy-salted cod (Gadus morhua). Because of the potential advantages of brine salting, especially mechanical adaptability, experiments were conducted to determine the practical merits of this process in the preparation of light-salted codfish of the Gaspé-cure type. In a batch operation using an equal weight of fish and brine, good results were obtained using 25% by weight salt solution and 5 hr of salting. With continuous circulation of brine of constant strength at 18 C, optimum conditions were achieved for salting using an 18% brine solution and an 8-hr exposure period. With a brine temperature of 10 C, at a brine concentration of 22%, a curing period of 12 hr was required. In each case the salted product must be "water horsed" for about 24 hr before drying.The water content of the product obtained by brining was higher than that of conventionally prepared fish, but the drying rate was also higher resulting in an overall drying time that was nearly the same. With efficient drying, it was possible to obtain a product which resembled the regular Gaspé-cure in appearance and in chemical characteristics.
Catecholamine and Carbohydrate Concentrations in Rainbow Trout (Salmo gairdneri) in Relation to Physical Disturbance
Authors: Nakano T. , Tomlinson N.
Published: April 2011

In rainbow trout (Salmo gairdneri) blood plasma concentrations of adrenaline (AD) and noradrenaline (NAD), and liver and heart concentrations of AD increased in response to severe physical disturbance. Skeletal muscle and anterior kidney concentrations of AD and NAD did not change detectably. Maximum plasma concentrations observed during disturbance of the fish were 0.20–0.36 μg AD and 0.05–0.09 μg NAD/ml. These plasma concentrations decreased relatively rapidly during recovery of the fish.Plasma glucose concentrations increased in response to disturbance, the magnitude and duration of the hyperglycemia being greater in those fish with initially high liver glycogen reserves. Liver glycogen concentrations in those fish with initially high (ca. 7%) concentrations apparently decreased in response to disturbance and increased during recovery of the fish, but no change was detected in liver glycogen concentrations in fish in which they were initially low (ca. 2.5%). Heart and skeletal muscle glycogen concentrations decreased in response to disturbance and increased during recovery.In skeletal muscle, the concentration of adenosine 3′,5′-phosphate and the proportion of phosphorylase in the a form increased in response to disturbance of the fish and decreased thereafter.
Effect of Aliasing on Studies of Long-Term Oceanic Variability off Canada's Coasts
Authors: Mann C. R. , Needler G. T.
Published: April 2011

not available
Transatlantic Migrations of Young Bluefin Tuna
Authors: Mather III Frank J. , Bartlett Martin R. , Beckett James S.
Published: April 2011

not available
Plasticity of Gillraker Number and Length in Oncorhynchus nerka
Authors: McCart P. , Andersen B.
Published: April 2011

not available