bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of the Bertalanffy Growth Equation to Problems of Fisheries Management: A Review
Authors: Allen K. Radway
Published: April 2011

The development of large modern fisheries has led to the overexploitation, with resulting less than optimal production, of many of our fish stocks. A need to develop management techniques which would make it possible to hold stocks and exploitation rates more nearly at optimal levels has led to the development and extensive study of mathematical theory relating to fishing. An essential feature of this theory is the yield equation which relates the obtainable yield to such stock parameters as the number of recruits, rate of growth at various stages of life, natural mortality rate, and intensity of fishing. A widely used form of the yield equation is that developed by Beverton and Holt (U.K. Min. Agr. Fish. Food, Fish. Invest. 19: 1–533, 1957). In this equation the growth component is represented by the well-known Bertalanffy growth equation (Bertalanffy, Human Biol. 10: 181–213, 1938):[Formula: see text]It is not possible, however, to represent the growth of all fish satisfactorily by this equation, and where this is not possible, the Beverton and Holt yield equation also does not give satisfactory results. This situation calls for the need to develop a more generalized equation, using a more widely applicable form of the growth curve. As Bertalanffy (Helgolaender Wiss. Meeresuntersuch. 9: 5–37, 1964) has pointed out, the original equation assumes that catabolic processes are proportional to the weight of the animal, whereas anabolic processes are assumed to be proportional to the surface area or to the 2/3 power of the weight, but in practice at least the latter relationship frequently does not hold. The present paper examines the effect of different values of the exponent in the catabolic and anabolic components of the growth equation upon the shape of the growth curve and particularly upon the proportion of final size at which the point of inflection occurs. The modified yield equation embodying the generalized growth equation can be solved by means of tables of the incomplete beta-function by an extension of the method of Jones (Joint Meeting ICNAF/ICES/FAO, Lisbon, Doc. P21, 1957).
Physiological Tolerances and Behaviour Responses of Five Species of Haustoriidae (Amphipoda: Crustacea) to Five Environmental Factors
Authors: Sameoto D. D.
Published: April 2011

Five species of haustoriid amphipods from Cape Cod, Massachusetts, differed in their tolerances to high temperature, desiccation, low salinity, and low oxygen concentration and in preferences for different sediment sizes. Two intertidal species, Haustorius canadensis Bousfield and Neohaustorius biarticulatus Bousfield, survived longer in air at 100% relative humidity and were more resistant to high water temperature than three species that are basically subtidal, Acanthohaustorius millsi Bousfield, Parahaustorius longimerus Bousfield, and Protohaustorius deichmannae Bousfield. All five species preferred sediments of a particular size range, the intertidal species selecting coarser sediments than the subtidal species. The sediment preference shown by the intertidal species could be changed by altering the organic conditions of the sediment by either drying or igniting the sediment. Acanthohaustorius millsi was the species most tolerant to low oxygen concentration and H. canadensis had the lowest oxygen consumption rate of the five species.The ecological significance of these findings is discussed in relation to the distribution of the five species on Cape Cod.
Caloric and Carbon Equivalents of Zooplankton Biomass
Authors: Platt Trevor , Brawn Vivien M. , Irwin Brian
Published: April 2011

In a study throughout 1 year at a station in St. Margaret's Bay, N.S., the caloric content per unit dry weight of zooplankton showed a fivefold variation. Along with all the available information from the literature, the data indicated that the dependence of caloric content of zooplankton (y) on per cent organic matter (x) could be described by the equation y = −3370 + 136 x − 0.514 x2. The caloric content may be predicted from per cent ash (A) and per cent carbon (C) by the equation y = 1351 + 106 C − 21.2 A. The relative stability of the caloric or carbon standing stock of zooplankton per unit water volume, compared with numbers or dry weight, may be an indication of some kind of regulatory mechanism controlling energy flow.
Serum Transferrin Systems and the Hemoglobins of the Pacific Halibut (Hippoglossus stenolepis)
Authors: Tsuyuki H. , Roberts E. , Best E. A.
Published: April 2011

Based on starch-gel electrophoretic analyses of serum proteins of 1092 specimens of Pacific halibut sampled from the eastern Bering Sea and northeastern Pacific Ocean southward to southern British Columbia, three molecular species of transferrins were encountered. A fourth rare type was postulated to explain the observation of some phenotypes involving this transferrin. These transferrins, either singly or in combinations of two, accounted for the theoretically possible 10 phenotypes of which 8 were actually observed. Hereditary control by four codominant alleles (TfA, TfB, TfC, and TfD) is postulated to explain the heterogeneity of the transferrin patterns. The collections were arbitrarily divided into 10 geographic areas and gene frequency analyses were used to determine population structure. Phenotypic distribution was shown to be independent of age and sex. Of the 10 areas, only the collection from southeastern Alaska proved not to be homogeneous. Preliminary analysis of blood hemoglobins indicated that these proteins are not of value in population analyses.
The Zoarcid Lycodopsis pacifica in Outer Burrard Inlet, British Columbia
Authors: Levings C. D.
Published: April 2011

Aspects of the biology of Lycodopsis pacifica were investigated during December 1965–November 1966 in outer Burrard Inlet, British Columbia. Trawls were used as sampling devices.After approximately age III, males appeared to have a different growth pattern than females. Females apparently had higher mortality rates than males. Spawning occurred from late August to January. Most males were mature at a length of 170 mm, and most females at 160 mm. The complements of mature eggs were small (average approximately 30). The mature eggs are large, with an average diameter of 5.0 mm. There is some evidence that parental care is involved in reproductive behaviour. The species fed primarily on molluscs, annelids, and Crustacea in the bottom mud.
Final Observations on the Survival of Planted Lake Trout in South Bay, Lake Huron
Authors: Budd J. C. , Fry F. E. J. , Pearlstone P. S. M.
Published: April 2011

Yearling lake trout were planted in South Bay, Lake Huron, an area with a sea lamprey population, each year from 1949 to 1955 with the exception of 1950. Fish were recaptured in pound and gillnets. Those recaptured in pound nets were tagged and released. Data from recaptures of tagged fish have been used to calculate yearly population estimates that were used to determine the annual mortality of certain year-classes. The fish were also examined for lamprey wounds and scars and the results tabulated according to the age of the fish.Before age IV annual mortality of South Bay lake trout does not appear to differ significantly from annual mortalities observed in lake trout populations in the absence of sea lampreys. Thereafter, annual mortality rates rise sharply and the population disappears at the age of VI or VII. No spawning population was maintained.Prior to age III no lamprey marks were observed on recaptured lake trout. From ages III to V the percentages of fish bearing lamprey marks increased from 5.2 to 38.8. This trend may continue through age VI but too few data are present to be certain. Before age VI there appears to be a direct correlation between annual lamprey marking rates and annual natural mortality rates.
Chronic Toxicity of Copper to the Fathead Minnow (Pimephales promelas) in Soft Water
Authors: Mount Donald I. , Stephan Charles E.
Published: April 2011

The maximum acceptable toxicant concentration of copper for the fathead minnow (Pimephales promelas, Rafinesque) in water having an EDTA hardness of 30 mg/liter (as CaCO3) was found to be between 0.13 and 0.22 of the 96-hr TLm value, using survival, growth, and reproduction to evaluate effect. In an earlier study the application factor for copper in water with an EDTA hardness of 200 mg/liter (as CaCO3) was found to be between 0.03 and 0.08 for the same species. Suggestions are made that should increase the accuracy and precision of future determinations of application factors.
Effect of Tidal Barriers Upon the M2 Tide in the Bay of Fundy
Authors: Yuen Kenneth B.
Published: April 2011

A model was constructed for the M2 tide in the Bay of Fundy, in which the two-dimensional hydrodynamical equations with quadratic friction were integrated in time. After calibration tests, in which the normal tide was reproduced, calculations were carried out to determine any changes from the normal configuration caused by the presence of tidal barriers in the vicinity of Cape Enrage, Cape Sharpe, and Cape Chignecto.The effect in each instance was a reduction of amplitude and an advancement of the time of high water. The maximum amplitude reductions were as follows: single barrier at Cape Sharpe, 15%; single barrier at Cape Enrage, 13%; both barriers at Cape Sharpe and Cape Enrage, 19 and 20%; twin barrier at Cape Chignecto, 21–27%.
Influence of Temperature on Gaffkemia, a Bacterial Disease of the Lobster Homarus americanus
Authors: Stewart James E. , Cornick John W. , Zwicker B. M.
Published: April 2011

The mean time to death for lobsters (Homarus americanus) infected with Gaffkya homari and kept at constant temperatures was 2 days at 20 C, 12 days at 15 C, 28 days at 10 C, 65 days at 7 C, 84 days at 5 C, and 172 days at 3 C. The lobsters were unable to mobilize at any of these temperatures systemic defenses adequate to eliminate the pathogen. No deaths that could be attributed to infection with G. homari occurred during the 250-day trial at 1 C; the pathogen, however, was not eliminated at this temperature but remained in the lobsters at low levels with virulence unchanged and gave rise to a fatal infection when the temperature was increased. Further studies showed that infected lobsters were adversely affected by a relatively rapid increase of 10 degrees C but not by a 5-degree C increase; a relatively rapid decrease of 15 degrees C but not 10 degrees C was adverse. Infected lobsters at 15 C were most sensitive to a 5-degree C decrease around the 12th day of the infection.
Meristic Analyses of Atlantic Mackerel, Scomber scombrus, from the North American Coastal Populations
Authors: MacKay K. T. , Garside E. T.
Published: April 2011

Mean counts of vertebrae, of anal and soft dorsal fin rays, and of peduncular finlets were identical in samples of Atlantic mackerel, Scomber scombrus, from the northern and southern breeding populations in the northwest Atlantic Ocean. This information, together with growth rates and biochemical evidence from the literature, suggests that although the populations occupy separate spawning regions there is sufficient exchange of individuals at other seasons to maintain considerable genetic continuity.
Glycolytic and Nucleotide Changes in the Critical Freezing Zone, −0.8 to −5 C, in Prerigor Cod Muscle Frozen at Various Rates
Authors: Nowlan Sandra S. , Dyer W. J.
Published: April 2011

Glycolytic and nucleotide changes during freezing at different rates were investigated in prerigor muscle from unexercised cod. Significant changes occurred during freezing as samples 1 cm thick in the center of a 2.8-cm thick pack cooled through the critical temperature zone from −0.8 to −5 C, but little further change occurred after the temperature had fallen below −5 C. The amount of change depended on the thermal arrest time (TAT) (time from −0.8 to −5 C). During rapid freezing with a TAT of 0.22 hr, the most significant change was a 39% dephosphorylation of creatine phosphate; small amounts of glycogen and acid-labile phosphorus were lost. Freezing at an intermediate rate (TAT, 5.4 hr) resulted in a loss of one-half of the initial glycogen and almost all of the creatine phosphate; also about one-third of the initial ATP was converted to IMP. After slow freezing (TAT, 20 hr) only traces of glycogen and high energy phosphorus compounds remained in most samples.Dephosphorylation of creatine phosphate, and degradation of ATP to IMP occurred more rapidly in freezing muscle at −1 C than in unfrozen muscle at 0 C. The rates of glycolysis were similar, but when the temperature dropped below −1 C there was an apparent increase in glycolytic activity.
Muscle Protein Polymorphism of Sablefish from the Eastern Pacific Ocean
Authors: Tsuyuki H. , Roberts E.
Published: April 2011

Muscle proteins of 897 specimens of sablefish, collected during 1963–67 in the northeastern Pacific Ocean, ranging from Unalaska Island, Alaska, to Cape Blanco, Oregon, were analyzed by starch gel zone electrophoresis. Without exception, all specimens fitted into one of three phenotypic protein patterns resulting from two polymorphic proteins appearing singly or in pairs. Hereditary control by two codominant alleles, MuA and MuB, is postulated to explain the heterogeneity of the muscle protein patterns. Phenotypic distribution was shown to be independent of age and sex. The collection was arbitrarily divided into 10 areas, and the gene frequencies used as population parameters suggested homogeneity but did not provide positive evidence of heterogeneity in the sablefish inhabiting the waters of the eastern Pacific Ocean. The implications of these results are discussed in the light of previously reported racial and tagging studies.
Discussion of Calculation of Power Function with Special Reference to Respiratory Metabolism in Fish
Authors: Glass Norman R.
Published: April 2011

The rationale for employing a nonlinear iterative least-squares technique for fitting the well-known power function to oxygen consumption–body weight data is set forth. Twenty-six sets of routine or standard metabolism data from six authors were used to demonstrate the relative merits of two methods of calculating parameter values for the power function. The conclusion was reached that if accuracy in predicting oxygen consumption over a wide range of values of body weight is desired, an iterative curve fitting method may be superior to the much used technique of performing a linear regression on logarithmically transformed data.
Effect of EDTA Treatment on Spoilage Characteristics of Petrale Sole and Ocean Perch Fillets
Authors: Pelroy Gretchen A. , Seman Jr. John P.
Published: April 2011

Ethylenediaminetetraacetic acid (EDTA) used in 1% solution as a dip extended the 0.5-C shelf life of petrale sole and ocean perch fillets by repressing growth of Pseudomonas spoilage organisms and formation of trimethylamine. Of the three salts compared, Na2EDTA and Na4EDTA were the most effective, extending shelf life of ocean perch fillets by 7–10 days, whereas Na2CaEDTA gave a 4-day extension over the control fillets. Vacuum packaging enhanced the effectiveness of EDTA as a preservative.
Nutrition and Chemical Composition of the Rhabdocoel TurbellarianSyndesmis franciscana, with Notes on the Taxonomy ofS.antillarum
Authors: Mettrick D. F. , Jennings J. B.
Published: April 2011

Histological, histochemical, biochemical, and ultrastructural studies show that digestion in Syndesmis franciscana (Lehman, 1946), a rhabdocoel entocommensal in the coelom and intestine of the sea-urchin Strongylocentrotus purpuratus from California, is both extra- and intracellular, involving an endopeptidase, exopeptidases, phosphatases, and a lipase. The gastrodermal cells are loaded with lipid globules, so that this substance forms over 25% of dry weight. Glycogen accounts for a further 19% dry weight. Over 85% of the glycogen is in the soluble lyo-form, as in adult endoparasitic helminths. Both the form and total amount of glycogen present suggest that the pattern of carbohydrate metabolism is more akin to the parasitic than the free-living platyhelminths.Syndesmis antillarum Stunkard and Corliss, 1951, a syndesmid from the Caribbean, is shown to differ both morphologically and physiologically from S. franciscana. The present synonymy of these two species is considered unjustified and incorrect.
Trawl-Board Sediment Sampler
Authors: Butler T. H. , Sheldon R. W.
Published: April 2011

The design and operation of an underway sediment sampler are described, with particular reference to exploratory shrimp fishing. The sampler is fitted onto the shoe of a trawl otter board and automatically collects a bottom sediment sample at the beginning of a trawl tow.
Rapid Cold-Branding of Salmon and Trout with Liquid Nitrogen
Authors: Mighell James L.
Published: April 2011

Liquid nitrogen (at −196 C) was successfully used as a coolant in a simple, inexpensive, and rapid method of marking salmon and trout with a metal branding tool. The marks, applied to as many as 650 fish per hour per marker, were consistently clear and readily identifiable for at least 14 months after application. No mortalities could be attributed to the branding technique among 4000 yearling coho salmon held for 2 months after marking.
Modification of the M2 Tide due to Barriers in the Bay of Fundy
Authors: Greenberg David A.
Published: April 2011

The one-dimensional channel equations with linear bottom friction are integrated numerically to determine the modification of the M2 tide for several cases of barriers in the bay. The barriers are treated as "complete barriers" in the sense that no flow is permitted through them.
Histological and Electron Microscopical Observations on Copper Poisoning in the Winter Flounder (Pseudopleuronectes americanus)
Authors: Baker Jeremy T. P.
Published: April 2011

Effects of high, medium, and low levels of copper on the morphology of winter flounder were investigated using routine histological techniques and electron microscope analyses.High and medium levels of copper resulted in fatty metamorphosis in the liver, necrosis in the kidney, destruction of the hemopoetic tissue, and gross changes in gill architecture. Seven other structures and organs were examined for copper-induced morphological changes but none were found.Light microscope studies showed that low levels of copper caused an extracted appearance in gill lamellae; the epithelial layer appeared vacuolated; the basi-lamellar region was reduced in thickness. Lamellar mucus cells were few compared with control specimens and chloride cells appeared in their stead.Electron microscope study of gill lamella from fish exposed to low levels of copper confirmed vacuolation in the epithelial layer. Also found were myelinlike figures, various membrane-bound vesicles, and apical homogeneous layers of reduced thickness. Increased amounts of particulate matter adhering to the external surface of the epithelial cells were apparent. Chloride cells were found instead of mucus cells.
Oxygen Consumption of Tilapia nilotica in Relation to Swimming Speed and Salinity
Authors: Farmer G. J. , Beamish F. W. H.
Published: April 2011

Oxygen consumption of Tilapia nilotica (L.) at 25 C was measured for various swimming speeds at salinities of 0, 7.5, 11.6, 22.5, and 30‰.Oxygen consumption for a given swimming speed and salinity increased linearly with weight when expressed on a double logarithmic grid. Slopes of regression lines relating oxygen consumption and weight were less than unity, ranging from 0.5117 to 0.9887.Generally, oxygen consumption at 0, 7.5, and 22.5‰ was approximately equal; values at 11.6‰ were lowest and those at 30‰ highest. Presumably, energy required for osmoregulation was least in the absence of an osmotic gradient (11.6‰) and greatest when the osmotic gradient was highest (30‰). Assuming energy required for osmoregulation was zero at the isosmotic salinity (11.6‰), it was estimated that approximately 29% of the total oxygen consumption was required for osmoregulation at 30‰ and 19% at 0, 7.5, and 22.5‰.Plasma osmotic concentration was used as an index of capacity for osmotic regulation. Concentrations for unexercised fish remained about the same at 0, 15, and 30‰. At no salinity were plasma osmotic concentrations for exercised and unexercised fish statistically different at P < 0.05. However, there was a trend for concentrations for exercised fish to decrease from the unexercised level at 0‰ and to increase from the unexercised level at 30‰. Only at 15‰ were concentrations similar for exercised and unexercised fish. Of the salinities tested, fish were able to osmoregulate most efficiently at 15‰, the salinity closest to the isosmotic salinity.
Hematological Study of Two Buffalofishes, Ictiobus cyprinellus and I. bubalus (Catostomidae)
Authors: Chlebeck Anne , Phillips Gary L.
Published: April 2011

A hematological study was made based on 10 specimens each of the buffalofishes Ictiobus cyprinellus and I. bubalus (Catostomidae). Average results of analyses of selected blood characteristics of I. cyprinellus and I. bubalus, respectively, were: hemoglobin content, 7.8 and 8.5 g/100 ml; erythrocyte count, 1.08 and 1.28 millions/mm2; hematocrit, 34.6 and 32.9%; mean corpuscular hemoglobin, 67 and 64 μμg; and leucocyte count, 23916 and 29004 cells/mm3. Types of leucocytes noted were lymphocytes, neutrophils, "secretory granulocytes," eosinophils, and thrombocytes. No basophils were found. The secretory granulocyte is apparently derived from the neutrophil series. The status of the secretory granulocyte in buffalofishes is discussed with reference to pertinent literature.
Some Salinity-Induced Changes in Growth, Pigments, and Cyclohexanetetrol Content of Monochrysis lutheri
Authors: Craigie J. S.
Published: April 2011

Growth rates of Monochrysis lutheri Droop increased with light intensity in seawater medium (SWM), whereas cells grown at either low NaCl (0.013 M) or high NaCl (1.02 M) showed reduced growth at higher light intensities with an optimal intensity near 0 05 g cal/cm2 per min.Chlorophyll and total carotenoids usually declined with increasing light intensity except in cells maintained on a high salt regime, when the carotenoid content remained high at all light intensities.The concentration of intracellular cyclohexanetetrol in SWM cells was approximately 0.3 M and was dependent upon the osmotic properties of the medium. Added NaCl, mannitol, sucrose, but not glycerol, caused accumulation of the cyclitol, whereas dilution of the medium caused its expulsion from the cells. Addition of 0.5 moles/liter of NaCl to SWM cells caused an 80–90% increase in cyclitol concentration within 4 hr; dilution of the medium reduced the cyclitol to the new steady state level within 10 min.
A Formulation of the von Bertalanffy Growth Curve when the Growth Rate is Roughly Constant
Authors: Knight William
Published: April 2011

The author contends that the parameters of any growth curve should be a direct description of the graphical appearance of the data. For growth that is even approximately linear this is not true of the von Bertalanffy curve in its usual form (von Bertalanffy, Human Biol. 10: 181–213, 1938). On the above grounds, an alternate form of the von Bertalanffy curve for use in such instances is proposed.
Marine Bacteria and Other Heterotrophs as Food for Zooplankton in the Strait of Georgia during the Winter
Authors: Seki H. , Kennedy Owen D.
Published: April 2011

Microbiological investigation was carried out in the waters of the Strait of Georgia during the winter to study the occurrence of heterotrophic microorganisms in relation to other particulate organic materials, including plankton and detritus. High microbial activity was measured in the euphotic zone, where marine bacteria and allied microorganisms were chiefly found on the particulate matter having diameter less than 25 μ. Their standing crop was estimated by different methods to be between 40 and 3000 mg C/m2 and some of this was consumed by the zooplankton, which were found to have concentrated the bacteria by a factor of around 105. Only the highest levels of microbial production were estimated to be sufficient for the growth of zooplankton and generally the bacterial activity was only sufficient to support a subsistence level of life for marine copepods in the Strait of Georgia.
Predation and the Evolution of a Stickleback (Gasterosteus)
Authors: McPhail J. D.
Published: April 2011

In western North America there are populations of Gasterosteus in which the male nuptial colour is a deep black rather than the normal bright red. Such black populations are usually allopatric to red populations, but in some areas the two forms occur in adjacent sympatry.The difference in male nuptial colour and a number of other morphological and physiological traits reflect genetic differences between black and red populations. Male nuptial colour functions as a partial isolating mechanism. Mate selection experiments indicate that females from red populations rarely accept a black male when they have a choice between a red or black male. Females from allopatric black populations also show a preference for red males, but females from black populations immediately upstream from a hybrid zone appear to mate randomly. The significant difference in mate preference between allopatric and sympatric populations of black females is evidence for the reinforcement of male colour as an isolating mechanism. The selective mechanism reinforcing colour as an isolating mechanism is hybrid inferiority due to genetic incompatibility and aberrant behaviour in hybrid males.A hypothesis is presented that persistent differential predation by an endemic predator (Novumbra) on the young concentrated near the male nest site was the selective force responsible for the evolution of the black genotype. Experiments demonstrate that Novumbra is differentially attracted to red males when given a choice between red and black males, and that the young of black sticklebacks possess an innate behavioural response to Novumbra that makes them significantly less vulnerable to predation by Novumbra.
The Black Hagfish, Eptatretus deani, from British Columbia
Authors: Bourne Neil , McAllister D. E.
Published: April 2011

The first two specimens of the black hagfish, Eptatretus deani (Evermann and Goldsborough), taken in British Columbia waters are reported and described.
Sexual Dimorphism in the Cyclopterid Fish Eumicrotremus orbis
Authors: Arita George S.
Published: April 2011

Eumicrotremus orbis exhibits marked sexual differences in the size and number of the taxonomically important dermal tubercles and in coloration. The tubercles in females are larger and more numerous than those in the males. Mature females are pale green whereas males are dull orange to reddish-brown. Eggs taken from ripe females collected during January and February 1967 averaged 2.0 mm in diameter. Each female carried an average of 202 eggs. The presence of recently hatched juveniles suggests that E. orbis spawns in February.
Transferrin Variants in Pacific Hake (Merluccius productus)
Authors: Utter Fred M.
Published: April 2011

Four transferrin bands were detected by starch-gel electrophoresis in serum and vitreous fluids of Pacific hake from Puget Sound, Washington, and off the mouth of the Columbia River. The patterns of the variants and their frequencies in samples from the two areas indicated that each band reflects one allele at a single locus. Frequencies of the alleles differed significantly between areas.
Synonyrny of the Polychaete Scoloplos acutus with S. arrniger
Authors: Curtis Mark A.
Published: April 2011

Some species of Scoloplos including S. acutus, have been described as differing from Seotroplos armiger by the absence of distinctive hooks (crotchets) in the thoracic neuropodia and by the absence of subpodial papillae in the region adjacent to the junction of thoracic and abdominal setigers. Although these species have previously been synonymized with S. armiger, little objective evidence has been put forth to support the synonymies and the species persist in the literature. Data presented here demonstrate that the presence of hooks and subpodial papillae is related to growth and so their absence cannot be considered a good criterion for the discrimination of separate species.
Toxicity of Yellow Phosphorus to Herring (Clupea harengus), Atlantic Salmon (Salmo salar), Lobster (Homarus americanus), and Beach Flea (Gammarus oceanicus)
Authors: Zitko V. , Aiken D. E. , Tibbo S. N. , Besch K. W. T. , Anderson J. M.
Published: April 2011

Yellow phosphorus is extremely toxic to aquatic life. In herring, salmon, and lobster, the toxic effect of phosphorus is irreversible and probably cumulative. For herring LT50 (hours) = 300/C0.87, where C = μg/liter of phosphorus. No clear indications of an incipient lethal level were found, an LT50 being obtained even at a concentration of 2.5 μg/liter. Incipient lethal levels of yellow phosphorus for lobster, salmon, and beach flea are 40 μg/liter, 18 μg/liter, and 3–4 mg/liter, respectively. Poisoned fish turn red and show signs of extensive hemolysis. Blood of lobster congeals, and after death the thorax may be filled with thick gel and the heart grossly distended. For lobster, LT50 (hours) = 300–0.17x, where x = product of phosphorus concentration and exposure time (μg days/liter). The oxidation of dispersions of yellow phosphorus in water is kinetically a first-order reaction with half-life of 2–7.5 hr. The adsorption of yellow phosphorus on a solid support such as bottom mud substantially decreases the rate of oxidation.
A Method of Selecting Trout Hybrids (Salvelinus fontinalis × S. namaycush) for Ability to Retain Swimbladder Gas
Authors: Tait J. S.
Published: April 2011

A method was developed for selecting hybrid trout for deep-swimming ability, for use in a breeding program to combine in one strain the early-maturing character of brook trout (Salvelinus fontinalis) with the deep-swimming ability of lake trout (S. namaycush). The method involves testing hybrids in pressure tanks and selecting individuals that, like lake trout, retain most of their swimbladder gas during the test period. For a sample of F2 hybrids the range of pressures at which the fish floated when anaesthetized was almost entirely between the medians for samples of the two parent species. Successive tests of marked individuals showed good repeatability of flotation measurements. The method is concluded to be reliable for large-scale selection of fish with ability to retain swimbladder gas.
Levels of Stable Zn and 65Zn in Crassostrea virginica from North Carolina
Authors: Wolfe Douglas A.
Published: April 2011

The concentration of zinc in oysters was highly variable — samples from relatively unpolluted estuaries of North Carolina contained, on the average, 85–245 ppm zinc, based on wet weight. Internal tissues, like adductor muscle and pericardial sac, had zinc levels less than half those of external tissues but zinc was nonetheless distributed uniformly throughout the animal tissues. During 1964–66, North Carolina oysters contained 2–20 pCi 65Zn from fallout per 100 g wet weight. Specific activity of 65Zn in these oysters during 1965–66 was in the range 90–300 pCi/g Zn, and was declining with an apparent half-life of 276 days.
Zinc Enzymes inCrassostrea virginica
Authors: Wolfe Douglas A.
Published: April 2011

Nearly all the zinc in oysters is bound, either to soluble high-molecular weight proteins or to structural cellular components such as cell membranes. Oyster alkaline phosphatase is a zinc metalloenzyme, as indicated by in vitro inhibition studies with various metal-binding agents. Dialysis of soluble tissue extracts at pH 7–9 removes up to 96% of the total zinc without effect on alkaline phosphatase. If alkaline phosphatase is considered representative of the metabolic functions of zinc in oysters, most of the zinc accumulated by oysters must be superfluous to the animal's requirements.
Effects of the Insecticide Sevin on Various Stages of the Dungeness Crab, Cancer magister
Authors: Buchanan David V. , Millemann Raymond E. , Stewart Nelson E.
Published: April 2011

Of the life-history stages of the Dungeness crab, Cancer magister, the early larvae are more sensitive to Sevin than are juveniles and adults. A concentration of 1.0 mg/liter did not affect egg hatching but prevented molting of all prezoeae to zoeae. The concentration that killed 50% of the first stage zoeae during a 96-hr exposure (96-hr EC50 for death) was estimated to be 0.01 mg/liter. Few zoeae were killed in 24 hr by 82.0 mg/liter, but the 24-hr EC50 for death within 15 days after the exposure was estimated to be 0.015 mg/liter. The 24-hr EC50 for cessation of swimming, which was not always permanent, was 0.0065 mg/liter. Survival of zoeae after 25 days exposure to concentrations of 0.0001, 0.00032, 0.001, 0.0032, and 0.01 mg/liter were 83, 60, 69, 21, and 0%, respectively, and control survival was 79%. Molting was delayed at a concentration as low as 0.0001 mg/liter.Young juvenile crabs are more sensitive to Sevin than are older juveniles or adults. The 24-hr EC50's for death or irreversible paralysis were estimated to be 0.076 and 0.35 to 0.62 mg/liter for second and ninth stage juveniles, respectively. The behavior, growth, and survival of juvenile crabs were not affected when the animals were exposed to 0.032 mg/liter of Sevin for 24 hr and then held in clean sea water for 44 days. The 24-hr and 96-hr EC50's for death or irreversible paralysis were 0.49 and 0.26 mg/liter, respectively, for adult crabs. After eating cockle clams that had just been exposed for 24 hr to 1.0, 3.2, and 10.0 mg/liter of Sevin, 22, 77, and 100% of adult crabs, respectively, were irreversibly paralyzed within 6 hr. The significance of these findings in field application of Sevin to control oyster pests and predators is discussed.
Deoxyribonucleic Acid Polymerase of Trout Liver Nuclei
Authors: Tarr H. L. A. , Gardner Linda
Published: April 2011

The DNA polymerase of intact trout liver nuclei behaved similarly to that present in mammalian tissues in its mandatory requirement for four deoxynucleoside triphosphates, Mg2+, and DNA primer. It was inhibited by DNase and pyrophosphate in comparatively low concentrations and by RNase and Actinomycin D in comparatively high concentrations. Soluble DNA polymerase was extracted from buffered suspensions of the nuclei by centrifugation at 100,000 g. It possessed properties very similar to those exhibited by the enzyme in intact nuclei. The polymerase activity of intact nuclei was increased by freezing and thawing, and the soluble enzyme was unstable at 30 C and lost most of its activity in 1 day at 0 C. The specific activity of the enzyme was 10–29 picomoles of deoxynucleoside triphosphate incorporated into DNA by 1 mg of protein in 1 hr at 25 C.
The Species Problem within Gasterosteus aculeatus on the Pacific Coast of North America
Authors: Hagen D. W. , McPhail J. D.
Published: April 2011

Two kinds of Gasterosteus aculeatus, leiurus and trachurus, are considered species in several streams and lakes in British Columbia. The two sticklebacks may act as species over a much wider range, but at present there is insufficient evidence for firm conclusions. The data of Miller and Hubbs (Copeia 1969: 52–69, 1969) given as evidence for introgression between leiurus and trachurus on the Pacific coast cannot be taken as well established. Should conclusive data for introgression be forthcoming, it would then seem that the two sticklebacks act as species in places and as subspecies in others. At least along the Pacific coast the pattern of variation found within Gasterosteus is exceedingly complex and cannot be accounted for wholly upon any simple explanation in terms of hybridization between leiurus and trachurus. There is evidence that much of the interpopulation variation is a result of adaptation and natural selection — not introgression. It will in fact require much more investigation before we can proclaim the causes of the variation we see so strikingly in Gasterosteus.
First Specimens of the Stonecat,Noturus flavus, from the Hudson Bay Drainage
Authors: Stewart K. W. , Lindsey C. C.
Published: April 2011

Nine specimens of stonecat were taken in the Red River 16 km south of Winnipeg, Man. This is the only known collection of the species from the Hudson Bay drainage. Ecological factors seem to be the main influence confining the species to its present restricted northern locality.
The Manefish, Caristius groenlandicus Jensen (Percomorphi: Caristiidae), in Atlantic Waters off Canada
Authors: Scott W. B. , Kohler A. C. , Zurbrigg R. E.
Published: April 2011

Morphometric and meristic data for the first recorded captures of Caristius groenlandicus in Canadian Atlantic waters in 1966 (1) and 1968 (7) are described and compared with previously published records.
Estimates of Seston Crops by Filtration with Glass Fiber Discs
Authors: Reed Dale F. , Reed Edward B.
Published: April 2011

Glass fiber filters were compared with centrifugation as a means of concentrating seston from a small fluctuating reservoir. Fifteen sets of samples drawn over a 2-month period showed that the filters removed about twice as much seston, by dry weight, as did the centrifuge.
Integrating Radiometer: A Self-Contained Device for Measurement of Submarine Light Energy in Absolute Units
Authors: Platt T. , Larsen E. , Vine R.
Published: April 2011

The design, construction, and use of a self-contained submarine radiometer is described. The instrument measures the time-integral of the downwelling irradiance at a given depth in absolute units. The measurement error at 20 m in turbid coastal water is less than 5%. The instrument is useful in primary production and heat budget studies, and could rind many applications in terrestrial ecology.
Marine Borer Activity in Test Boards Operated in the Newfoundland Area during 1967–68
Authors: Evans John W.
Published: April 2011

Marine wood borer activity is reported on the basis of an examination of 26 test panels that were submerged for approximately 1 year (from May 1967 to June 1968) at selected locations in the Newfoundland area. Limnoria lignorum (Rathke) was present consistently at each location, whereas Teredo navalis Linnaeus and Psiloteredo megotara (Hanley) were relatively uncommon.
Graphical Estimation of Rates of Mortality and Growth
Authors: Green Roger H.
Published: April 2011

A method is presented by which the individual growth rate and the population mortality rate can be estimated graphically in certain populations, given only knowledge of maximum individual size and of average size at two times of the year. The four graphs that are given may be used in several different ways, depending on the information available.
Benthic Fauna Colonization of a New Reservoir with Particular Reference to the Chironomidae
Authors: Paterson C. G. , Fernando C. H.
Published: April 2011

At the time of first filling of Laurel Creek Reservoir in the spring of 1967 the benthic fauna consisted of submerged terrestrial organisms and obligate and facultative rheophilic species. Two months after initial filling substantial populations of colonizing limnophilic species developed in the habitat whereas the terrestrial and obligate rheophilic components were lost. By the 4th month the fauna was dominated by euryoxybiontic limnophiles and by facultative species. In the period immediately prior to reservoir drainage in the autumn of 1967 the population densities of the euryoxybiontic chironomids declined whereas polyoxybiontic species continued to increase in abundance. These changes in the dominance hierarchy of the chironomid fauna were associated with the partial loss of the rich deposits of organic debris by siltation and decomposition. Survival of winter drainage of the reservoir by many limnophilic species produced an appreciably different pattern of colonization when the reservoir refilled in 1968. During the second summer of the reservoir's existence most euryoxybiontic chironomids further declined in abundance and were replaced by polyoxybiontic forms as the dominant species. The facultative species originally derived from the creek fauna are adapted to a wide range of environmental conditions and the modifications of the reservoir habitat with time had little effect on their abundance.
Laboratory and Field Tests of Modified Sphyrion Tags on Lobsters (Homarus americanus)
Authors: Scarratt D. J.
Published: April 2011

Mortalities of lobsters held in the laboratory and tagged with sphyrion tags inserted dorsally between the carapace and abdomen (subcarapace tag) and between the second and third abdominal segments (abdomen tag) did not differ significantly. Premoult tag loss was negligible. The subcarapace tag was retained significantly better through moulting.Returns of subcarapace-tagged and abdomen-tagged lobsters released on the fishing grounds in June, 11 weeks before the August 10 opening of the fishing season, were lower than returns of carapace-tagged lobsters released in early August. More subcarapace-tagged than abdomen-tagged lobsters were returned, and a higher proportion had moulted. Growth was comparable to that reported in the literature. Few lobsters were recaptured during the following fishing season, 14–16 months after liberation, and none subsequently. Returns from lobsters less than 63.5 mm carapace length (sublegal) when tagged were extremely low. Poor survival may be related in part to time of release. Some injury to internal organs may occur with both tags. The subcarapace tag is clearly superior but may be of limited value in the field for lobsters below 63.5 mm carapace length.
Distribution of Triaenophorus crassus Parasites in Whitefish Flesh and its Significance to Automatic Detection of the Parasites with Ultrasound
Authors: Freese M.
Published: April 2011

The three-dimensional distribution of Triaenophorus infection in the whitefish (Coregonus clupeaformis) body and the ultrasonic echos received from the parasite cysts are studied in relation to the problem of detecting the parasites with ultrasound. It is shown that ultrasonic scanning of only 15% of the total surface area of a whitefish is required to illuminate (on the average) 70% of the total number of cysts in the body. As a result the search effort required for effective ultrasonic parasite detection can be greatly reduced. A considerably larger ratio of infection (3:2) for the right and left sides of the body is observed than has been previously reported. It is also shown that in the epaxial muscles a parasite is much more likely to be encysted near the surface than deep inside the flesh. Measurements of the ultrasonic cyst-echo durations yielded a distribution with two peaks of different amplitudes indicating a preponderance of spindle-shaped cysts as is actually observed. A negligible percentage of the echos in the distribution are less than 2 μsec in duration; the median width is 6.4 μsec. An outline is given of how these findings can be used to reduce the error rate in an automatic detection system. The paper concludes with a brief discussion of the effects of the transducer aperture on the latter distribution.
Diel Vertical Movements and Feeding of Underyearling Sockeye Salmon and the Limnetic Zooplankton in Babine Lake, British Columbia
Authors: Narver David W.
Published: April 2011

The use of a high frequency echo sounder and a midwater trawl in Babine Lake, British Columbia, in 1967 revealed a precise diel vertical movement of underyearling sockeye salmon. From early July to September, from about 1.5 hr after sunrise to 1.5 hr before sunset, the young sockeye were in two distinct layers at about 20 and 35 m, each layer about 6 m thick. About 1.5 hr before sunset the two layers began to ascend. About 0.5 hr after sunset all fish were within 3 m of the surface, and during darkness they were dispersed throughout the top 5–15 m with most fish being below the thermocline. Soon after the first light of dawn the fish usually tended to move toward the lake surface and then descended rapidly to the daytime depths.By early October the pattern had changed markedly. During daylight the fish were still found in roughly two layers at about 24 and 40 m. However, the evening ascent did not commence until about 0.5 hr before sunset, the ascent was much slower, and the fish did not come to the surface but were dispersed between 9 and 27 m. This change in behaviour was temporally associated with a cooling of the epilimnion and a decrease in intensity of feeding.Although the zooplankton of Babine Lake is composed of eight major species, only Bosmina coregoni and the calanoid copepod Heterocope septentrionalis displayed pronounced diel vertical movements. The former inhabited the surface waters during the day and were found in maximum abundance at 12–21 m at night. The latter was found at 21–30 m during the day and the surface waters at night. The major part of the zooplankton standing stock was found above 9 m.Young sockeye fed most intensively in the evening as they approached the surface and again at dawn just as they commenced the descent. At those times the most common food item was Daphnia longispina, followed by B. coregoni and H. septentrionalis. These three species were strongly selected by young sockeye, since they were numerically much less abundant than other limnetic zooplankton species. In August, terrestrial insects were occasionally of major importance. At midday the upper layer of sockeye (about 20 m) was feeding on H. septentrionalis whereas the lower layer (about 35 m) was not feeding or was feeding at a low intensity.The double layer of young sockeye during daylight occurred at least in the North Arm of Babine Lake and may be related to feeding. In July and August the fish in the upper layer had less food in the pyloric section of the stomach from 0900 to 1300 hr than did fish in the lower layer, whereas the volumes of food were similar in the two layers by late afternoon. Fish in the upper layer had much more fresh H. septentrionalis in the cardiac section from 1200 to 1800 hr than did fish in the lower layer. The ecological significance of the diel vertical movement is discussed briefly.
Enhancement by Glycerol of Phototrophic Growth of Marine Planktonic Algae and its Significance to the Ecology of Glycerol Pollution
Authors: Cheng Joseph Y. , Antia Naval J.
Published: April 2011

The effects of low (0.05 M) and high (0.5–1.0 M) concentrations of glycerol on the growth of 18 species of marine phytoplankters belonging to 7 algal classes were studied. The algae were grown in axenic culture in sea water enriched with nitrate, orthophosphate, silicate, trace-metal ions, vitamin B12, thiamine, biotin, and buffered at pH 7.6–7.8. Apart from a chrysomonad (Prymnesium parvum) and a cryptomonad (Chroomonas salina), none of the species showed any significant growth on glycerol in the absence of light. However, in the presence of light, glycerol enhanced the growth of 16 species, in particular members of the Chrysophyceae and Cryptophyceae, one diatom (Phaeodactylum tricornutum), one rhodophyte (Porphyridium cruentum), and one chlorophyte (Nannochloris oculata). A high concentration of glycerol was required for inducing or asserting growth enhancement of certain species, but was equally effective as the low concentration or was inhibitory to other species. The enhancement effect was observed in the growth rate and in the peak population density, which in many instances was several times that from nonglycerinated cultures and suggested photoheterotrophic growth. Some species showed obvious cytological and metabolic changes from growth on glycerol. The ecological implications of glycerol pollution of sea water are discussed.
A Submersion–Emersion Sensor, for Intertidal Biological Studies
Authors: Druehl Louis D. , Green John M.
Published: April 2011

An instrument for use in intertidal biological studies that determines, at any instant, whether a given intertidal site is under or above water is described. The instrument measures microsubmersions and microemersions caused by surf.