bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproduction in Sphyrion lumpi, a Copepod Parasitic on Redfish (Sebastes spp.)
Authors: Squires H. J.
Published: April 2011

Simultaneous development of ova in ovaries and of embryos in eggsacs of Sphyrion lumpi suggested that more than one spawning of this parasite was probable in nature. The functional morphology of the trunk also suggested that spawning and eggsac formation occurred during a short period when the ova were ready to be extruded. Six arbitrary stages of maturity of females were defined. Only 27% of the adult females were ovigerous. Thirteen males were found on 12 of the 263 females examined. Fecundity estimated from numbers of eggs in eggsacs was 6–30 thousand eggs at trunk sizes of 30–45 mm.
Procedure for Analysis of Schooling Behavior
Authors: Hunter John R.
Published: April 2011

A method for the analysis of schooling behavior applicable to field and laboratory studies is presented. Three indices were developed to measure the behavior of a school, from motion pictures. Two of the indices are measures of the distance among individuals in a school, and the other is a measure of the differences in orientation among the individuals. A value for each index was calculated for each motion-picture frame analyzed. A coordinate reader and digitizer used to analyze films permitted the operator to record automatically on IBM cards the X and Y coordinates for the positions of the head and tail of each fish in a frame. A computer program was written to calculate the three indices from the coordinates, to convert the measurements to actual distance, and to make statistical comparisons.Laboratory experiment on the influence of food deprivation on schooling behavior of juvenile jack mackerel, Trachurus symmetricus (Ayres) indicated: schools became compact immediately after feeding; the intervals among fish expanded during a deprivation period; and differences in orientation were related to the size of the individuals.
Changes in Levels of Hemoglobin, Oxygen, Carbon Dioxide, Pyruvate, and Lactate in Venous Blood of Rainbow Trout (Salmo gairdneri) During and Following Severe Muscular Activity
Authors: Black Edgar C. , Manning Glenville T. , Hayashi Koichiro
Published: April 2011

The effects of severe muscular exercise were studied in [Formula: see text]-year-old rainbow trout (Salmo gairdneri). Changes in the oxygen and carbon dioxide content of blood taken from the heart together with alterations in blood levels of pyruvate and lactate were followed in 14 separate conditions. Observations were also made on fish swimming steadily in a rotating annulus.
Characteristics of Scales from Pink Salmon (Oncorhynchus gorbuscha) Transplanted from the Glendale River in Central British Columbia to the North Harbour River in Newfoundland
Authors: Bilton H. T.
Published: April 2011

not available
Responses to Light of Young Atlantic Salmon (Salmo salar) and Brook Trout (Salvelinus fontinalis)
Authors: Gibson R. John , Keenleyside Miles H. A.
Published: April 2011

Responses of young Atlantic salmon (Salmo salar L.) and of brook trout (Salvelinus fontinalis (Mitchill)) to different levels of illumination and to overhanging and submerged cover were compared in the laboratory. At surface illuminations between 0.4 and 160 ft-c trout were either slightly photopositive or showed no preference for light or dark areas, while salmon were photopositive. At illuminations above 300 ft-c both species were photonegative when the light area had a smooth, unbroken substrate. Under these conditions starvation induced salmon into the light, but trout remained photonegative, although slightly less so than well-fed trout. With submerged cover (plants, broken flowerpots, etc.) in the light area, salmon were strongly photopositive, while trout were photonegative. Salmon were less photopositive, but still preferred the light area, with submerged cover in both dark and light areas, in most experiments trout maintained position at the edge of the shadow caused by overhead cover, looking out into the light area from the dark.The significance of these results to habitat segregation by the two species where they are sympatric in nature is discussed.
Blood Volumes of Three Salmonids
Authors: Smith Lynwood S.
Published: April 2011

Two species of salmon (Oncorhynchus kisutch, O. nerka) and steelhead and rainbow trout (Salmo gairdneri) were injected with Evans blue dye. Typical excretion slopes and a minimum mixing time of 60 min were determined by sampling blood through a dorsal aorta cannula for up to 5 hr after injection. Extrapolation of the excretion slope to zero time provided an estimate of the dye dilution which, with hematocrit measurements, gave blood volume estimates ranging from 5.4 ± 0.8 to 6.9 ± 1.8 ml/100 g.A new method of using Evans blue was tested in which dye was injected into one fish and its plasma reinjected into other fish. Blood volume estimates for O. kisutch were 4.5 ± 1.5 by this method as compared with 6.2 ± 2.0 ml/100 g for Evans blue used in the usual manner in the same individuals.Blood volumes estimated from plasma samples taken 20, 25, and 30 min after injection while the fish were maintained out of water were 35% less than after the same fish were returned to water and a second estimate made from additional samples taken 1, 2, and 3 hr after the original dye injection.
Design of Small Holding Tank for Fish
Authors: Alderdice D. F. , Brett J. R. , Sutherland D. B.
Published: April 2011

not available
Developmental Rate and Vertebral Number in Salmonids
Authors: Garside E. T.
Published: April 2011

Eggs of the brook trout and the rainbow trout were incubated at various constant levels of temperature and dissolved oxygen to test the hypothesis that vertebral number in fish is controlled, within limits, by the developmental rate. The mean vertebral number in both species decreased with increased rate of development which was caused by higher temperature and conversely the mean vertebral number in both species increased with decreased rate of development. The number of vertebrae is shown to be inversely related to the rate of development, expressed as the reciprocal of the number of days in the period of numerical determination of vertebrae in each species. The slopes of the regressions are −0.45 and −1.15 for brook trout and rainbow trout, respectively, and are perhaps, characteristic of the species. Variations in the usual type of trend of vertebral number with different developmental conditions, as reported by some investigators, are discussed and a possible explanation for some of these variations is proposed.
Comparative Electropherograms of Representatives of the Families Petromyzontidae, Esocidae, Centrarchidae, and Percidae
Authors: Uthe J. F. , Roberts E. , Clarke L. W. , Tsuyuki H.
Published: April 2011

The starch gel electropherogram of muscle myogens and blood hemoglobins of representatives from the families Petromyzontidae, Esocidae, Centrarchidae, and Percidae were found to be within the limits of species specificity with some exceptions. Evidence of polymorphism was found in the muscle myogen of Stizostedion vitreum of the family Percidae. Only one type of homozygous pattern, designated A, was found in specimens from Great Slave lake, while both the homozygotes A and B as well as the heterozygote AB were found in samples from Lake St. Clair. Further genetically interpretable polymorphisms were also found in the minor protein zones. These natural chemical markers are discussed from the standpoint of their usefulness in subpopulation analyses. The presence of protein zones of common electrophoretic mobilities in three species of the family Petromyzontidae indicated marked resemblances of the muscle myogens at the family level. Total plasma proteins of P. marinus showed vast changes during their parasitic and nonparasitic stages of development. The muscle myogens of some members of the family Centrarchidae also showed strong familial relationships. In hybrids of this group biosynthetic systems for muscle myogens and plasma proteins of both parents were present.
Bathymetric Distribution of Sea Stars (Asteroidea) off the Northern Oregon Coast
Authors: Alton Miles S.
Published: April 2011

During U.S. Bureau of Commercial Fisheries' Atomic Energy Commission trawling investigations in waters adjacent to the mouth of the Columbia River, a total of 54 species and one subspecies of sea stars was collected from bottom depths of 50–1050 fath. The sea stars in the area of study can be divided into four faunal assemblages by benthic zones: (1) an outer sublittoral fauna (50–108 fath) consisting of several shallow-water species, some of which have their apparent maximum depth of occurrence in this zone. The number of species and the availability of sea stars per hour of trawling is much lower in this zone compared to the other benthic zones in the study area; (2) an upper bathyal fauna (122–258 fath) consisting of several species having either a continuous or discontinuous circumboreal distribution; (3) a lower bathyal fauna (275–500 fath) characterized by a large number of species and a high availability of sea stars in terms of numbers and weight per hour of trawling. Several of the more frequently occurring and abundant species in this zone belong to genera endemic to the northeastern Pacific; and (4) an abyssal fauna (900–1050 fath) consisting almost entirely of species belonging to cosmopolitan genera.The bathyal-abyssal zone (585–850 fath) is considered a zone of transition because of the intrusion into this zone of elements of the sea star fauna from both the lower bathyal and the abyssal.
Life Histories of two Species of Catostomid Fishes in Sixteenmile Lake, British Columbia, with Particular Reference to Inlet Stream Spawning
Authors: Geen G. H. , Northcote T. G. , Hartman G. F. , Lindsey C. C.
Published: April 2011

Inlet spawning migrations of longnose suckers (Catostomus catostomus) and white suckers (Catostomus commersonnii) in Sixteemile Lake commenced in the spring when daily maximum temperatures in the inlet reached S and 10 C, respectively. Migrating fish were trapped in the stream near the lake, marked by subcuticular injection of liquid latex, and recovered during their lakeward migration following spawning. Upstream migrants from later parts of the run spent less time in the stream than fish from early parts of the run. Longnose suckers returned to the lake before white suckers. The females of each species returned before the males. Spawning mortality was 10–40%. Suckers marked as mature spawners in 1956 made up an appreciable proportion of the spawning run for several years thereafter. Some fish spawned in several successive years. Scales did not provide a reliable measure of age of spawners, but recoveries of marked fish suggested maximum ages of 12–16 years. Growth of adult fish was 10–20 mm/year. Estimates of the adult population size were 2000 longnose and 800 white suckers of which 25–50% spawned each year. Low annual recruitment was indicated in these slow-growing populations. The downstream movement of sucker fry was nocturnal and largest when stream levels were high and the water turbid or the nights particularly dark. Peak fry migration was approximately 1 month after spawning. Several investigations have indicated the general similarity of inlet spawning migrations of rainbow trout, redside shiner, squawfish, and the two species of suckers.
Estuarine Spawning of Atlantic Salmon
Authors: Saunders J. W.
Published: April 2011

not available
The Acute Inflammatory Reaction in Two Different Tissues of the Pacific Oyster, Crassostrea gigas
Authors: Pauley Gilbert B. , Sparks Albert K.
Published: April 2011

This study describes the histopathology and the associated gross pathological alterations of experimentally induced acute inflammation in the oyster, Crassostrea gigas, after turpentine injections into two different tissues, the adductor muscle and the Leydig cell area. Under optimum conditions the oyster can successfully combat a toxic substance such as turpentine, with the adductor muscle being more capable of handling such an irritant than the Leydig cell area. Inflammation in vertebrates is compared with that in the oyster.
Annual Growth Cycle, Growth Potential, and Growth Compensation in the Bluegill Sunfish in Northern Indiana Lakes
Authors: Gerking Shelby D.
Published: April 2011

Eight lake populations of the bluegill sunfish (Lepomis macrochirus) with widely varying growth rates exhibited a surge of growth in the spring followed by a progressively declining growth rate in late summer and autumn. The growth rate declined as age increased; in no case did the growth of an older age group exceed that of a younger age group in the same year. Increase in length was estimated from marginal growth of scales collected at various times throughout 1962 and 1963.The beginning of the growing season, assumed to correspond in time with the formation of the annulus, was estimated to average April 8 in 1962 and April 26 in 1963. The time of annulus formation was observed in one lake by collecting scales when the mark was appearing, and in the others it was estimated by extrapolation of a regression between marginal scale growth and time. The end of the growing season, or the time when 90% of annual growth had been achieved, came on September 10 in 1962 and on September 27 in 1963. The length of the growing season varied among the lakes and between years in the same lake. The range was from 98 to 189 days with an average of 152 days. In one lake the season was a month longer in 1963 than in 1962, but this difference was not evident in the others.The annual rate of growth and the length of the growing season were related. Populations with a rapid growth rate had a longer growing season than those with a slow growth rate. A long season was typified by a somewhat earlier time of annulus formation than a short one and by a considerably longer period of growth in the late summer and autumn.All populations had the same growth potential as judged by weight increment of group III fish during the first month of the season. The first month's increments were 12.6, 12.9, and 13.9 g for populations with rapid, intermediate, and slow annual growth rates respectively. The population with the shortest growing season and the lowest annual growth had the greatest increment during the first month.The strong relationship between size and the time of annulus formation suggested a possible mechanism of growth compensation. Since the smaller fish of a year class begin to grow earlier than do their larger companions, growth compensation may result from the advantage in time gained by the smaller group, assuming that the growing seasons of it and the faster growing members of the cohort end at the same time. Most of the mechanisms offered heretofore have depended upon a difference in the time of hatching between two groups of fish.Consideration is given to an explanation of the annual growth cycle in terms of temperature, photoperiod, and the possible influence of growth hormone at different times of the year.
Vertical Distributions of Some Benthic Marine Algae in a British Columbia Inlet, as Related to Some Environmental Factors
Authors: Druehl Louis D.
Published: April 2011

The vertical distribution of 12 benthic marine algae and one animal are described for Indian Arm, an inlet in British Columbia. In general, the vertical distributions had distinct limits and the relative vertical positions of the species were constant throughout the inlet. The relative vertical distributions of the biota within the inlet are essentially the same as described for the northeast Pacific by other authors concerned with the same biotic elements. However, the upper limits of Laminaria saccharina (L.) Lamouroux, Costaria costata (Turn.) Saunders, and Constantinea subulifera Setchell are from 1 to 3 m lower within the inlet than elsewhere, whereas those of Agarum cribosum Bory, Fucus evanescens C. Agardh, and Sargassum muticum (Yendo) Fensholt are essentially the same within and outside of the inlet. For the remaining species studied (Enteromorpha compressa (L.) Greville, E. linza (L.) J. Agardh, E. intestinalis (L.) Link, Monostroma fuscum (Postels & Ruprecht) Wittrock, Ulva lactuca Linnaeus, Navicula grevillei (C. Ag.) Cleve, and Balanus glandulus (Darwin)) there were no comparable distribution data outside of the inlet.Available data suggest the deepening of the upper limits of some algae in Indian Arm reflects their intolerance to the high temperature and low salinity of the surface waters of the inlet.
The Use of Adipose Fin Pigmentation for Distinguishing Between Juvenile Chinook and Coho Salmon in Alaska
Authors: Dahlberg Michael L. , Phinney Duane E.
Published: April 2011

not available
Comparative Electropherograms of the Family Catostomidae
Authors: Tsuyuki H. , Roberts E. , Kerr R. H. , Uthe J. F. , Clarke L. W.
Published: April 2011

The muscle myogens of Catostomus catostomus exhibit polymorphism. Specimens from Great Slave Lake and Babine Lake were homozygous to pattern type A, whereas those from Lake Superior possessed patterns homozygous to A and B as well as the heterozygote AB. Those of C. commersoni, Moxostoma macrolepidotum, M. anisurum, and M. erythrurum were relatively uniform, showing only odd variants. The two specimens of Ictiobus bubalus examined displayed different patterns. Blood hemoglobin patterns of M. macrolepidotum existed in five, M. anisurum in two, and C. commersoni in three polymorphic forms. The number of specimens of I. bubalus, M. melanops, and Carpiodes cyprinus examined was insufficient to assess the existence of polymorphism. Muscle myogen electropherograms of the eight species investigated reflect overall family resemblances, distinctive generic groupings as well as phylogenetic relationships which compare favorably with those in existence. Intergradations might occur upon a more extensive coverage of this family and which might somewhat obscure this overall picture are discussed.
α-Tocopherol in Some Atlantic Fish and Shellfish with Particular Reference to Live-Holding Without Food
Authors: Ackman R. G. , Cormier M. G.
Published: April 2011

Muscle tissue from four species of Atlantic fish (cod, dogfish, mackerel, and flounder) and one species of Pacific fish (sablefish) was examined for total lipid and α-tocopherol content. The values for α-tocopherol in both lean and fat major muscle tissues fell in the range 210–330 μg/g lipid. Lipids from cod and mackerel livers showed slightly higher values (430 μg/g lipid). These results are interpreted as the result of a lipid integration process in which the tocopherols produced by phytoplankton are redistributed with lipid through various lower life forms and small fish until similar levels are reached in the principal fats of larger fish. The metabolically active dark (lateral line) muscle of cod was twice as rich (630 μg/g) in α-tocopherol in proportion to lipid as white muscle tissue from cod. Lobster muscle was exceptionally rich (> 1200 μg/g) in α-tocopherol. Examination of starved cod indicated that large amounts of α-tocopherol remained after lipid depletion. Frozen flounder fillets showed no significant amount of α-tocopherol after 4 to 8 months frozen storage.Eight species of Atlantic shellfish were examined in toto. Oysters and quahogs lost their α-tocopherol after several weeks of live-holding without food. In the oysters this was accompanied by muscle weakening and an objectionable odour. Most filter feeding species in the normal environment had 1–2.5% lipid and α-tocopherol values of 300–600 μg/g lipid, but a high proportion of organic detritus in the diet of mussels from one area reduced this level. The quahogs examined were extremely low (~0.60%) in lipid and therefore relatively high in α-tocopherol in proportion to lipid (> 1000 μg/g). Herbivorous periwinkles and accompanying predatory dogwinkles had the highest α-tocopherol contents on a fresh weight basis (35 and 21 μg/g tissue) and high values in proportion to lipid (~850 μg/g).
Moult in the Pacific Harbour Seal Phoca vitulina richardi
Authors: Stutz Sherwood S.
Published: April 2011

not available
Quality of Pacific Coast Dogfish During Frozen Storage
Authors: Boyd J. W. , Southcott B. A. , Schmidt P. J.
Published: April 2011

Pacific coast dogfish (Squalus suckleyi) were skinned, frozen, glazed, and stored at −5, −10, −20, and −30 C to determine the extent of oxidative rancidity, colour change, protein denaturation, and lipid hydrolysis during storage. Belly flaps from dogfish carcasses were tested under similar conditions. Discoloration of the red outer muscle of carcasses was the initial significant change in quality. Initial odour and flavour changes in defrosted carcasses were detected after 22 and 70 days storage at −10 and −20 C respectively; no significant changes were evident in carcasses after 180 days storage at −30 C. Slight fading of the pink colour of belly flaps was observed after storage for 50 days at −20 C and for 160 days at −30 C. A slight acidic type flavour was detected in belly flaps after 99 days storage at −20 C.There was a slight relationship between the extent of protein denaturation and lipid hydrolysis in dogfish muscle during frozen storage.
Food of the Dolphin, Coryphaena hippurus Linnaeus, and of the Yellowfin Tuna, Thunnus albacares (Lowe), from Barbados, West Indies
Authors: Lewis John B. , Axelsen Fritz
Published: April 2011

not available
Physical and Chemical Characteristics of Ogac Lake, a Landlocked Fiord on Baffin Island
Authors: McLaren Ian A.
Published: April 2011

Ogac Lake is the small (148 ha) landlocked head of a fiord with three distinct basins. It receives highest spring tides (maximal range 12 m, as high as 1.2 m above lake level) monthly during the open-water season through a narrow entrance. The predictable inflows displaced about one-quarter of the lake's volume in 1957. The lake is meromictic, fresh at the surface and 28‰ salinity at depth. Some 55 kg/m2 salt lost in surface outflow in summer was more than restored by the tides by the end of 1957. Deep salinities did not change between 1951 and 1962. Vertical attenuation of light is adequately accounted for by chlorophyll alone. The lake is much warmer than the nearby sea. Temperature inversions are caused by cold tidal water and perpetuated by vertical stability. The gross annual heat budget in 1957 was 22,000 cal/cm2, about the same as in the nearby sea, but higher than in a freshwater lake. Heating from below a few meters to 30 m can be accounted for by radiation alone. About 20% of radiation reaching the bottom subsequently appeared as heat in the water immediately overlying the bottom, thus implying restricted horizontal transfer. Oxygen was absent below 25–32.5 m, which may approximate the compensation level in this and similar lakes. Oxygen differences between basins are partly controlled by morphometry. Distinct oxygen minima in 1957 were associated with temperature minima and caused by concentrations of zooplankton. Vertical distribution of pH parallels that of oxygen. Specific alkalinities seem slightly higher than in normal seawater. Phosphate showed a distinct and stable minimum just above the anoxic layer and was as high as 14.3 μg-at/liter within that layer. Nitrate was relatively low and maximal just above the anoxic layer. Although nutrient levels seemed partly related to morphometry in the three basins, no evidence of nutrient enrichment of bottom water was found in late summer. The tides contribute negligible nutrients to the lake. The character of Ogac Lake compared with similar lakes derives from the great tidal amplitude and narrow connection with the sea, as well as from its small size and sheltered setting.
A Brief Survey of the Profundal Benthic Fauna of Lakes in Manitoba
Authors: Slack H. D.
Published: April 2011

The profundal benthic fauna of nine lakes lying along the margin of the Precambrian Shield in the Province of Manitoba was investigated during August 1963, and is described with particular attention to the midges (Diptera: Chironomidae).Comparison with a Scottish lake, similarly situated with respect to Precambrian rocks, showed no close agreement in the distribution of species of Chironomidae. This can be credited to differences in the Palaeozoic rocks adjoining the Precambrian.Chironomus tentans and C. decorus were most numerous and most frequent at water depths up to 15 m whereas C. anthracinus and Chironomus sp. A were generally in water over 20 m.In Falcon, Reed, and Morton lakes, C. anthracinus tended to be more successful where sediments contained appreciable amounts of allochthonous debris and to give way to Chironomus sp. A where sediments were autochthonous.
Use of Indophenol Method for Estimation of Ammonia Excreted by Freshwater Fish
Authors: Cocking A. W.
Published: April 2011

not available
Determination of Isopropyl Alcohol in Fish Protein Concentrate by Solvent Extraction and Gas–Liquid Chromatography
Authors: Ackman R. G. , Hingley H. J. , Power H. E.
Published: April 2011

The isopropyl alcohol residues in fish protein concentrates prepared with this solvent can be determined by a hot extraction technique employing methyl acetate as the solvent and gas–liquid chromatographic analysis of the extract. Studies on vacuum stripping of fish protein concentrates and analysis of various samples suggest that the isopropyl alcohol is trapped mechanically inside particles because of formation of an impervious shell during drying.
Amino Acid Composition of Myosin from Trout Muscle
Authors: Buttkus H.
Published: April 2011

The amino acid composition of myosin from the white muscle of trout has been determined and was found to be closely similar to that of rabbit myosin. Thirteen of the amino acid residues were present in concentrations identical to those of rabbit myosin or agreed within less than 3%. Valine, glycine, and methionine were present in slightly greater proportions. The histidine and proline contents of trout myosin differed from rabbit myosin by three residues per 105 g of protein and represented the greatest difference on a per cent basis. The possible significance of these differences is discussed in relation to the lower enzymatic activity and the lower thermal stability of trout myosin. The apparent specific volume of trout myosin calculated from the amino acid composition [Formula: see text] was identical to that obtained by density measurements. An apparent molecular weight calculated from the amino acid analyses was 500,027 ± 44.
Mate Selection in a Population of Sockeye Salmon (Oncorhynchus nerka) of Mixed Age-groups
Authors: Hanson Arthur J. , Smith Howard D.
Published: April 2011

Anadromous Skeena River sockeye mature and spawn mainly at ages 42 and 52. Lesser numbers of 32, 53, and 63 and 64 fish, and non-anadromous kokanee, may spawn in the same stream. Mate selection by the different types was studied by observing salmon of known length and using the relationship found between length and age in dead, spawned fish.Fish of all lengths tended to mate with similar sized fish. Small males were less successful in holding mates than were large males because they could not successfully defend redds against larger intruders. Small males spent more time alone than large ones and frequently lay in groups behind mating pairs. The term "satellite male" is used in describing the behaviour. Small females mated with large males but spent more time alone than did large females.The genetic implications of mating within age-groups are considered.
Figularia quaylei: A New Bryozoan from the Northeast Pacific
Authors: Powell N. A.
Published: April 2011

not available
Primary Production in Two Small Lakes of the Northern Interior Plateau of British Columbia
Authors: Narver David W.
Published: April 2011

not available
Line Fishing at Ocean Station P, 50°00′N, 145°00′W
Authors: LeBrasseur R. J.
Published: April 2011

not available
Exploitation of Multiple Stocks by a Common Fishery
Authors: Paulik G. J. , Hourston A. S. , Larkin P. A.
Published: April 2011

A complete analytical solution is presented for the problem of finding the common rate of exploitation that maximizes total sustained yield from a mixture of stocks when each stock follows a Ricker reproduction curve. A computer program is described which solves this problem for up to 20 stocks varying in both reproductive potentials and absolute sizes. Some aspects of the management of Pacific salmon and fishing strategies are discussed in relation to the question of obtaining maximum yields when harvesting mixtures of stocks under various constraints.
The Ultrastructure of the White Striated Myotomal Muscle of the Cod, Gadus morhua
Authors: Bishop C. M. , Odense P. H.
Published: April 2011

The structure of the white skeletal muscle of the cod (Gadus morhua) is described. The peripheral fibrils are ribbon-like and rectangular in cross section with the long axis normal to the sarcolemma. The inner fibrils are mainly polygonal in cross section. Most of the mitochondria and nuclei are peripheral to the fibrils and next to the sarcolemma. The arrangement of the contractile proteins is typical for striated muscle, and the sarcoplasmic reticulum and transverse tubular system are similar to those in other white skeletal fish muscle. A distinct N-band is apparent with indications of branching and reorientation of the actin filaments. Mitochondria are often closely associated with the Z line.
Records of the Atlantic Walrus, Odobenus rosmarus rosmarus, from Newfoundland
Authors: Mercer M. C.
Published: April 2011

not available
Atlantic Salmon Caught in the Irminger Sea
Authors: Jensen Jens Møller
Published: April 2011

not available
Erratum: Correct Spelling of Alectridium aurantiacum
Authors: Peden Alex E.
Published: April 2011

not available
Biosynthesis of Aldosterone and 18-Hydroxycorticosterone from Corticosterone by Interrenal Tissue of a Teleost (Clupea harengus harengus)
Authors: Truscott B. , Idler D. R.
Published: April 2011

not available
Analysis of the Southern Gulf of St. Lawrence Cod Population
Authors: Paloheimo J. E. , Kohler A. C.
Published: April 2011

The Gulf of St. Lawrence cod stock supports a fishery with recent annual landings around 65,000 metric tons. Traditionally, fish have been taken by baited hooks, but beginning in 1947 trawl fishing has gradually become the major fishing method.Introduction of trawling with concurrent increase in landings from an average of 30,000 metric tons prior to 1947 to 65,000 metric tons since then appears to have greatly changed the composition of the stock. The changes were characterized by the lowering of the average size of fish and of the abundance in weight of the commercially fished sizes, and the increasing of the abundance of the pre-commercial sizes.Available statistics permit estimation of growth, recruitment, and productivity parameters for the stock. Analysis suggests an inverse relationship between stock density and both growth and recruitment, the overall effect being an increased productivity.If the observed population changes are responses to increased fishing, then per-recruit models are not appropriate to predict the effects of any past or future regulations. Models providing for differential growth efficiencies, and competition and food-related recruitment relationship are required.
Starch in the Oceans
Authors: Bursa Adam S.
Published: April 2011

Starch observed in arctic waters of Canada, in the Baltic and Mediterranean seas, in the North Atlantic and Indian oceans, and in the waters about Bermuda, the Virgin Islands, and Jamaica is formed mostly in Gymnodinioideae, benthic algae, and higher aquatic plants and rarely in planktonic Chlorophyceae. In these phytoflagellates the fragile pellicle breaks when there are critical changes in salinity, temperature, or pressure and is subsequently decomposed by bacteria. The starch retains its shape after destruction of the protoplast, and accumulates in large quantities in aquatic habitats. Standing crops of free starch grains mark past blooms and mass mortalities of phytoplankton. The largest potato-like starch grains found in the oceans appear to be derived from the ocellar lenses of Warnoviaceae.Though Protozoa and various herbivores may ingest free planktonic starch, they were not observed to digest it. Large standing crops of starch and monosaccharides derived from amylolysis may affect nutrition in some animals, and influence the optical and chemical properties of sea water. Amylogenesis in some dinoflagellates starts from chondriosomes which are specialized in this process. In Prorocentrideae starch is formed within the ectoplasmic reticulum.
Problems Involved in the Quantitative Extraction of Glycogen and High-Energy Phosphorus Compounds in Frozen Cod Muscle
Authors: Nowlan Sandra S. , Dyer W. J. , Fraser Doris I.
Published: April 2011

Extraction of cod muscle with 0.3 N perchloric acid followed by digestion of the residue in potassium hydroxide yielded an average of 16% more total glycogen than did classical digestion with 30% KOH. However, the differences tended to be less at higher glycogen levels. It was suggested that glycogen may be partially degraded during digestion with KOH, although no glycogenosis occurred during contact with alkali prior to heating. The proportion of residual glycogen not extracted by acid varied from 23% in unfrozen muscle to about 40% in liquid nitrogen-frozen and in slowly frozen muscle.Significant degradation of glycogen and high energy phosphorus compounds in frozen prerigor cod muscle was avoided by weighing samples in insulated beakers chilled by liquid nitrogen to prevent warming or thawing, and by homogenizing immediately on addition of acid extractant. Extraction with acid enabled the simultaneous determination of glycogen and phosphorus compounds on the same sample. Special sampling procedures were employed to reduce the sampling error due to variation in glycogen distribution along the fillet.
A Subcutaneous Dart Tag for Fish
Authors: Pletcher F. T.
Published: April 2011

not available
Calorific Values of Some Invertebrates in Lake Mendota, Wisconsin
Authors: Wissing Thomas E. , Hasler Arthur D.
Published: April 2011

not available
Differences between North American and European Populations of Balanus balanoides Revealed by Transplantation
Authors: Crisp D. J.
Published: April 2011

Transplants of specimens of Balanus balanoides from North Wales to Newfoundland, Canada, confirmed two innate differences between European and North American forms of the species. Breeding took place later in transplanted European populations. The eggs of the European form, though maturing later and therefore at a slightly lower temperature than the North American form, were distinctly smaller.The time of breeding both in the North American and European forms was earlier at higher latitudes, at higher shore levels, and in shelter.
First Records of the Sculpins Myoxocephalus thompsonii and Cottus ricei from the Ottawa Valley, Southwestern Quebec
Authors: Delisle Claude , Vliet W. Van
Published: April 2011

not available
Eastern Extension of the Range of the Blackspotted Stickleback, Gasterosteus wheatlandi, in Newfoundland
Authors: Garside E. T. , Kerekes J. J.
Published: April 2011

Blackspotted sticklebacks, Gasterosteus wheatlandi, were collected at Northeast Arm, Bonavista Bay, Newfoundland (48°39′N, 53°55′W). This is the most easterly occurrence reported for Canadian waters.
Structure, Development, and Behaviour of New Strigeatoid Metacercariae from Subtropical Fishes of South America
Authors: Szidat Lothar
Published: April 2011

Eighteen species of metacercariae of the order Strigeatoidea (Trematoda, Digenea) are described from tropical and subtropical freshwater fishes of Argentina. Sixteen of them belong to the superfamily Strigeoidea and two to Clinostomatoidea. Ten are new species, five belong to previously known trematode species, and three are not specifically named.On the basis of the morphology of these metacercariae, probable life cycles and host–parasite relations are discussed. A general conclusion is drawn that the South American trematodes are more primitive than their counterparts from other continents.Different groups of fish hosts are recognized, each with a different history of association with their present environment. Originally marine fishes adapted to life in fresh water with the aid of increased endocrine activity, primarily thyroid activity. The high levels of endocrine secretions affected the parasites of these fishes, causing metacercariae to develop neotenically. The hosts which were originally freshwater appear to exert less influence on their parasites. Their metacercariae have a more or less normal course of development.Attention is drawn to the evolution in behaviour of strigeoid metacercariae. Primitive species infect less protected sites in the host. With progressive evolution, increasingly more protected sites are selected by the parasite. The evolution culminates in infection of the lens of the eye, which offers the best protection to the parasite against destructive influences of the environment.It is suggested that the metacercariae are guided to their selected infection site by an "engram," or a specific memory, developed and fixed in the course of many generations. New research into parasite behaviour is urged.
Auditory Masking and the Critical Band in Atlantic Cod (Gadus morhua)
Authors: Buerkle Udo
Published: April 2011

Auditory masking was determined for cod by using five half-octave bands as masking stimuli and as signals. For each of 15 cod, masking noise was kept constant at 10 db re 1 microbar in one band while thresholds were determined for signals in all five bands. Results indicate masking to be most pronounced when noise and signal coincide in frequency, and to drop off as frequency separation between noise and signal increases. Masking is calculated in terms of threshold in relation to masking noise level, and varies from about 11 db when signal and noise are in the same band to about −19 db when they are in bands furthest removed from each other. Estimates of critical bands are made from the results.
Movements and Homing of Cutthroat Trout (Salmo clarki) from Open-Water Areas of Yellowstone Lake
Authors: Jahn Lawrence A.
Published: April 2011

Cutthroat trout (Salmo clarki) showed in-season homing after displacement from their spawning tributaries to Yellowstone Lake during June–August 1966 and 1967. Of 300 nonanesthetized trout tagged and displaced from Clear and Cub creeks to three release points (0.5–22.0 km) in the lake and to the mouth of Clear Creek, 38.3% homed, 10.0% strayed, 2.7% were caught by anglers, and the remainder were unaccounted for. Anosmic (olfactory chambers plugged) and blind-anosmic fish homed in significantly lower percentages than nonanesthetized and control groups. Fish released just outside the mouth of the homestream had the shortest average homing time, but the average homing time for fish displaced 22.0 km from the homestream was shorter than for those displaced 5.0 km away. Homing percentages for trout tagged after being tracked individually in the open lake were similar to those for trout in the group tagging experiments, but the former had longer average homing times than the latter.The directions of orientation of fish tracked in open water were generally toward the homestream, the directions usually coinciding with those of the sun azimuth. However, fish taken from the east side of the lake went west-northwest when tracked late in the afternoon and fish taken from the west side of the lake went east-southeast when tracked in the morning, these directions being away from those of the homestreams. Orientation was affected by current. Mean directions for males and females were generally not significantly different. Average swimming speeds and vector lengths for males and females were about the same. Immature cutthroat trout were trained to use a light source as a reference point for orientation.
Infectious Pancreatic Necrosis: Clinical and Immune Response of Adult Trouts to Inoculation with Live Virus
Authors: Wolf Ken , Quimby M. C.
Published: April 2011

Mature feral rainbow trout were inoculated with infectious pancreatic necrosis (IPN) virus and held at 12.5 C for 3 months to produce antibody and to determine whether or not disease would occur. Disease was not observed, but IPN virus-neutralizing antibody was found in pre-inoculation serum indicating the likelihood of prior infection. As measured by Neutralization Index, the immune response varied from weak to very strong. Neutralizing antibody was not found in sera from mature specific pathogen-free rainbow and brook trout. Although IPN virus also failed to produce clinical disease in adult brook trout it did establish a transient asymptomatic infection, and this resulted in high levels of neutralizing antibody.
Lactate Dehydrogenase Isozymes in Longnose and Blacknose Dace (Rhinichthys cataractae and R. atratulus) and Their Hybrid
Authors: Clayton J. W. , Gee J. H.
Published: April 2011

Electrophoresis of tissue extracts of both longnose and blacknose dace reveals five isozymes corresponding to tetramers of heart and muscle type subunits. The species are readily distinguished by the greater electrophoretic mobility of longnose dace isozymes that contain heart type subunits. The F1 hybrid displays the multiple band pattern expected in a fish able to produce two kinds of heart subunit. In addition a variant type of muscle lactate dehydrogenase has been detected in the longnose dace.
Activity Periods of Some Fishes in Heming Lake, Canada
Authors: Lawler G. H.
Published: April 2011

On the basis of the numbers of fish caught per unit of time in Heming Lake during a spring–summer period, the white sucker (Catostomus commersoni) was most active during daylight. The following species were most active during darkness: northern pike (Esox lucius), whitefish (Coregonus clupeaformis), and walleye (Stizostedion vitreum vitreum).
Principal Acid-Soluble Nucleotides in Adductor Muscle of the Scallop Placopecten magellanicus and Their Degradation during Postmortem Storage in Ice
Authors: Hiltz Doris Fraser , Dyer W. J.
Published: April 2011

In scallop adductor muscle stored at 0 C, postmortem degradation of adenosine triphosphate (ATP), the predominant nucleotide at death, primarily follows the route ATP → adenosine diphosphate (ADP) → adenosine monophosphate (AMP) → adenosine → inosine → hypoxanthine (Hx). In one lot of scallops, however, inosine monophosphate (IMP) was present as an intermediate along with AMP. Hence, an alternate pathway, similar to that in fish muscle, whereby AMP is degraded to inosine and Hx via IMP rather than adenosine, may exist under certain (undefined) conditions. ATP dephosphorylation was much slower than in fish muscle; however, a rapid turnover of the intermediates in the degradative sequence, indicating relatively high activities of the enzymes catalyzing these reactions, resulted in the formation of appreciable amounts of Hx (3–4 μmole/g) within the edible storage period. In preliminary tests, taste scores correlated well with Hx contents, suggesting that measurement of Hx content may be a useful index of quality in scallop meats.Column chromatographic analyses showed that adenine nucleotides and their degradation products accounted for about 90% of the total acid-soluble purines and pyrimidines in scallop adductor muscle, with nicotinamide adenine dinucleotide and uridine diphosphate glucose as the principal minor nucleotide constituents. The muscle also contained considerable amounts of homarine (2–3 μmole/g). Glycolysis showed no relation to nucleotide degradation, both processes demonstrating a relatively slow postmortem catabolic rate in scallop muscle.
Growth and Vertical Distribution of the Glacier Lanternfish, Benthosema glaciale, in the Northwestern Atlantic
Authors: Halliday R. G.
Published: April 2011

Benthosema glaciale (Reinhardt, 1837) collected off Nova Scotia can be aged using otoliths, one transparent otolith ring being laid down each year. Maximum age attained is at least [Formula: see text] years and maximum length is 68 mm. There is no sexual dimorphism in growth. Part of the population spawns for the first time at age 2 and all at subsequent ages.In the northwestern Atlantic, B. glaciale is abundant in water with temperatures of 4–16 C and is found in temperatures higher than 18 C. Daylight depth range is at least 80–290 fath, the centre of distribution being below 250 fath. At night they are caught from the surface to at least 275 fath with the centre of distribution between 25 and 50 fath, indicating a diurnal vertical migration of over 200 fath for at least part of the population. Older, larger fish are found deeper than young fish at night.
An Inflammatory Lesion in an American Shad, Alosa sapidissima
Authors: Warner Ronald W. , Katkansky Stanley C.
Published: April 2011

An adult male American shad, Alosa sapidissima, with an external swelling simulating a neoplasm was collected from the Russian River, California. Histological examination of the large cone-shaped protuberance disclosed it to represent chronic inflammation and repair in response to injury and infection. The combined findings suggest the lesion may have originated from a lamprey bite.
Atresia and Year-Class Abundance of Northern Pike, Esox lucius, in Two Missouri River Impoundments
Authors: June Fred C.
Published: April 2011

Widespread atresia in northern pike ovaries was associated with low year-class abundance in three successive years, 1966–68, in Lake Oahe and Lake Sharpe, South Dakota, two large Missouri River impoundments. Atresia was associated with fluctuations in water temperature and level that apparently interrupted spawning.
Prevalence of Naturally Acquired Agglutinating Antibodies Against Aeromonas salmonicida in Hatchery Trout in Central Pennsylvania
Authors: Krantz George E. , Heist Carroll E.
Published: April 2011

A survey for naturally acquired antibodies against Aeromonas salmonicida in brook and brown trout in central Pennsylvania hatcheries showed great variation in the percentage of reactive individuals (0.8–87%) within 24 populations. Antibodies were not detected in fish less than 12 months old, and the percentage of serologically reactive individuals increased with the age of the population. Prevalence of antibodies in yearling trout populations in which furunculosis was epizootic was about twice as great as in fish experiencing enzootic furunculosis.
Sonic Tag for Large Decapod Crustaceans
Authors: Lund Jr. William A. , Lockwood Jr. Russell C.
Published: April 2011

Construction of a sonic tag designed for use on large decapod crustaceans is described. The circuit design permits tuning at various frequencies and its low current drain results in a transmitter life of over 2 weeks. The tag and power supply are packaged for attachment to the carapace and the battery pack is easily replaced and the tag reusable. The tag is now being used to study the daily movements and activities of the American lobster, Homarus americanus.