bluuebunny/crossref_metadata_2025 huggingface dataset:
Thecate Hydroids from the Shelf Waters of Northern Canada
Authors: Calder Dale R.
Published: April 2011

Based largely on collections from the Calanus–Salvelinus expeditions, 54 species of thecate hydroids were identified from the shelf waters of northern Canada between northeastern Newfoundland and the Alaska–Yukon border. Common species included Halecium muricatum, Calycella syringa, Campanularia integra, C. speciosa, C. volubilis, Gonothyraea loveni, Filellum serpens, Lafoea gracillima, Sertularella polyzonias, S. tricuspidata, Sertularia schmidti, and S. similis. Halecium groenlandicum, H. scutum, Cuspidella procumbens, Calycella gracilis, and Sertularia schmidti are new records for North America; Ptychogena lactea is previously known from this continent only as the medusa. Twenty-two species are reported in northern Canada for the first time, bringing to 71 the number of thecate species recorded from the region. Nearly half of the 71 species recorded are circumpolar in distribution, and over two-thirds transgress both arctic and subarctic zones.Most samples had a paucity of hydroids, particularly those from the high arctic. Collection records indicate that the most favourable regions for hydroids in northern Canada are the Strait of Belle Isle, eastern Ungava Bay, eastern Hudson Strait, northern and southeastern Hudson Bay, Foxe Channel, and northern Foxe Basin.
Elimination of Bacteria by the Northern Quahaug (Mercenaria mercenaria): Environmental Parameters Significant to the Process
Authors: Heffernan W. Paul , Cabelli Victor J.
Published: April 2011

A study was conducted to determine the influence of various environmental parameters on the ability of the northern quahaug, Mercenaria mercenaria, to cleanse itself of artificially accumulated Escherichia coli. The elimination of E. coli to low residual levels in the quahaugs placed in sea water free of E. coli for 48-72 hr was dependent on their initial E. coli content and, hence, the level of the organism in the contaminating water. Extending the contamination interval from 6 hr to 14 days did not adversely affect the ability of the animals to cleanse themselves of the organisms they accumulated. Optimal elimination was obtained within the following environmental limits: temperature, 10–20 C; salinity, 22–3‰; flow rate, > 13 ml/min per animal; turbidity, trace to 25 Jackson Turbidity Units. When the ambient temperature of the water from which the animals were collected was less than 10 C, the elimination of E. coli was decreased. Preliminary data were presented to demonstrate the importance of examining the variability in the response of individual animals.
Maturity, Mating, and Egg Laying in the Spider Crab, Chionoecetes opilio
Authors: Watson J.
Published: April 2011

Morphometric measurements and gonad examination of the spider crab, Chionoecetes opilio, showed that 50% maturity occurred at about 57 and 50 mm carapace width for males and females, with minimum sizes at maturity of 51 (males) and 47 mm (females). Both sexes were mature at sizes considerably below the commercially acceptable size of 4 inches (102 mm) carapace width. After maturity, positive allometric growth was demonstrated for males. Females do not moult after reaching maturity. The small vasa deferentia found in soft-shelled mature males suggested that only hard-shelled males were capable of mating. A hard-shelled male successfully mated with a soft-shelled mature female. Field and laboratory observations suggest that more than one brood is commonly produced from one mating.The minimum size limit for commercial landings allows some mature males capable of mating to be left on the fishing grounds. Retention of this limit seems unlikely to affect the breeding potential of the population.
Effect of Solitude on Time Between Fourth and Fifth Larval Molts in the American Lobster (Homarus americanus)
Authors: Cobb J. Stanley
Published: April 2011

Larvae held individually in containers spent an average of 12 days in the fourth stage. When held two larvae per container, one molted after an average of 12 days, the second after an average of 16 days. Duration of the fourth stage was not affected by gravel, shelter or bare bottom conditions, or illumination varying from <1 lux to 310 lux.
Food of Flathead Sole (Hippoglossoides elassodon) in East Sound, Orcas Island, Washington
Authors: Miller Bruce S.
Published: April 2011

Flathead sole (Hippoglossoides elassodon) in East Sound fed on both benthic organisms (clams, polychaetes, and pea crabs) and nektonic organisms (mysids, fishes, and shrimps). The smallest sole (40–179 mm total length (TL)) ate primarily mysids, but as the fish increased in size they utilized first shrimps and then fishes (mainly herring) and some clams. All except the largest sole (320–440 mm TL) also continued to feed heavily on mysids. Fish larger than 320 mm had the highest number of empty stomachs during the warmer months of the year whereas those smaller than 320 mm had the highest number empty during the colder months. In mature fish, the number of empty stomachs increased during the peak of spawning.
Efficiencies of Various Grabs and Corers in Sampling Freshwater Benthos
Authors: Flannagan John F.
Published: April 2011

None of several samplers compared in limited tests in Lake Ontario gave realistic estimates of benthos in all substrates encountered. The Ponar and Shipek grabs, the only samplers that functioned in gravel, came closest to all-sediment samplers. In sand, however, the Franklin–Anderson grab appeared to be much more efficient than either of these two samplers. In mud the Ekman grabs gave the highest mean numbers of animals per m2.In trials in Lake Winnipeg profundal mud, hand-taken diver's core samples being used as a quantitative standard, only the Fisheries Research Board multiple corer and the standard Ekman grab gave quantitative results for total macrobenthos. However, the multiple corer collected significantly fewer chironomids, and the standard Ekman grab significantly fewer oligochaetes, than did the diver's cores. There were indications that the tall Ekman grab was either not tall enough or too heavily weighted for use in soft sediments and that a small improvement in design could make both this and the standard Ekman more efficient. Most of the samplers apparently sampled some groups of organisms much better than others. Neither the Ponar grab nor the tall weighted Ekman grab sampled the chironomid or oligochaete populations satisfactorily. However, both grabs indicated densities of sphaeriids not significantly different from the diver's samples.
Preferred Temperature of Yearling Lake Trout, Salvelinus namaycush
Authors: McCauley R. W. , Tait J. S.
Published: April 2011

Preferred temperatures were determined for yearling lake trout acclimated to 5, 10, 15, and 20 C. Acclimation temperature had virtually no effect on preferred temperature. The final preferendum was 11.7 C, which is about 2 degrees C warmer than the temperature at which lake trout are most commonly caught in thermally stratified lakes.
Morphological Variation in the Burhot (Lota lota) and Recognition of the Subspecies: A Review
Authors: Pivnička Karel
Published: April 2011

A review of the morphometric and meristic variations in 893 specimens of the burbot (Lota lota) from 18 freshwater areas representing the range of the species, showed that Lota lota lacustris (= maculosa), with a short, high caudal peduncle and low meristic values may be distinguished from Lota lota lota, with a long, low caudal peduncle and high meristic values. Lota l. lota occurs from the Volga River system through Siberia and Alaska to the Mackenzie River system in Canada. The populations from the Elbe River and the Danube River are on the periphery of this subspecies, to which it clearly belongs. Lota l. lacustris occurs in southernmost Canada, the United States, and western Europe. Both Lota l. leptura (Hubbs and Schultz, 1941) and Lota l. kamensis (Markun, 1936) are synonyms of Lota l. lota (Linnaeus, 1758).Clinal variations in the means for various characters of the species were found as follows. All meristic values and length of the caudal peduncle as a percentage of standard body length, in general, increased eastward from western Europe as far as 120°E and then decreased toward New England. Predorsal and preanal lengths generally increased eastward from western Europe to New England. The following generally decreased from western Europe eastward to 120°E and then increased toward New England: head length, interorbital width, postpectoral length, and depth of caudal peduncle as a percentage of standard length; depth of caudal peduncle as a percentage of its length; and postpectoral length as a percentage of predorsal length.
Adjustment of Buoyancy in Blacknose Dace,Rhinichthys atratulus
Authors: Gee J. H.
Published: April 2011

The stream-dwelling blacknose dace (Rhinichthys atratulus) required 84 hr to adjust from moderately negative to neutral buoyancy when transferred from running to still water, and 132 hr to adjust from neutral to moderately negative buoyancy when transferred from still to running water. This adjustment was achieved partly by loss or addition of swimbladder gases and partly by altering the pressure of gases within the swimbladder, and accompanied slight changes in swimbladder length.
Comparison of Mysis relicta and Pontoporeia affinis as Possible Intermediate Hosts for the Acanthocephalan Echinorhynchus salmonis
Authors: Brownell Willard N.
Published: April 2011

Pontoporeia affinis (a known vector of Echinorhynchus salmonis) and Mysis relicta from Cayuga Lake were fed to yearling lake trout to determine if the parasite would be introduced into the fish. Pontoporeia is definitely a carrier of E. salmonis larvae; Mysis apparently is not.
A Multiple Corer for Sampling Profundal Benthos
Authors: Hamilton Andrew L. , Burton William , Flannagan John F.
Published: April 2011

A multiple corer for sampling the benthos of profundal sediments is described. This sampler is relatively simple to construct and is light (approximately 17.5 lb (7.9 kg)) and easy to use. Four core samples are taken simultaneously and trials reported elsewhere indicate that in soft sediments the samples taken are generally superior to those collected with most, if not all, of the more conventional samplers tested.
Effects of Dieldrin on Glutamic Oxaloacetic Transaminase in Poecilia latipinna
Authors: Lane Charles E. , Scura Edward D.
Published: April 2011

Serum glutamic oxaloacetic transaminase activity in the sailfin mollie, Poecilia latipinna, increased significantly in fish exposed to the pesticide dieldrin. All test fish were killed within 72 hr in 0.012 ppm.
Spawning Behaviour of the Chestnut Lamprey (Ichthyomyzon castaneus)
Authors: Case Brian
Published: April 2011

Spawning behaviour of the chestnut lamprey, Ichthyomyzon castaneus, was observed June 11 and 12, 1968, in coarse gravel near the tailrace of a dam in the Rat River, Manitoba, a tributary of the Red River. No description of spawning behaviour of this species has been previously published.
Seasonal Variations in Condition of Larval Herring in Boothbay Area of the Maine Coast
Authors: Chenoweth Stanley B.
Published: April 2011

The relative condition values for larval herring (Clupea harengus harengus L.) in the Boothbay area of the Maine coast were lowest in winter: in February in 1965, 1966, and 1967 and in January in 1968. Low water temperatures and a scarcity of food are suggested as reasons for the poor condition. Larval condition showed the greatest variation in 1964–65, and in February 1965 reached the lowest point for the 4 years. The evidence suggests that larval mortality was unusually high during that winter.
Fecundity of Greenland Halibut (Reinhardtius hippoglossoides) in the Newfoundland–Labrador Area
Authors: Lear W. H.
Published: April 2011

Fecundity estimates of 45 Greenland halibut from the Newfoundland–Labrador area were related to length and age. Fecundity increased with both length and age and varied from 15,000 to 215,000 eggs.
The Tropical Loliginid Squid Sepioteuthis sepioidea from the Northwest Atlantic
Authors: Mercer M. C.
Published: April 2011

A juvenile male specimen of the tropical corallophilic loliginid squid Sepioteuthis sepioidea (Blainville, 1823) is reported from Woods Hole, Massachusetts. Nearest recorded populations are at Cape Kennedy, Florida, and Bermuda at distances of 1440 and 950 km respectively. From current patterns it is inferred that the specimen was more likely wafted from the former area.
Distribution and Abundance of Tubificid (Oligochaeta) Species in Toronto Harbour, Lake Ontario
Authors: Brinkhurst R. O.
Published: April 2011

The tubificid oligochaetes build up populations in excess of 200,000/m2 in Toronto Harbour. Pollution-tolerant species in great abundance are located around the mouth of the Don River, whereas small numbers and some less tolerant species are found near the island shores. There is no evidence of diurnal rhythms in the vertical distribution of the worms in the sediment. Dry weights for tubificids are about 16% of the wet weight for fresh-starved worms. The ash content averaged 34% of the dry weight for worms with a gut full of mud, but 11% for worms clear of gut contents.
Postmortem Glycolytic and Other Biochemical Changes in White Muscle of White Sucker (Catostomus commersoni) and Northern Pike (Esox lucius) at 0 C
Authors: Manohar S. V.
Published: April 2011

Postmortem biochemical changes in the white muscle of white sucker and of northern pike were, in general, similar to those observed in other species as reported previously by other investigators. However, glycogen content of pike was found to remain relatively high even after 7 days of storage in ice. This is in contrast to the findings with several other species, including white sucker, where the muscle glycogen is practically completely degraded in 3–4 days. Higher glycogen content in the posterior portion of pike muscle as compared with that in the anterior portion may partly explain the apparent high glycogen content in the muscle of this fish after several days of storage.
5′-Nucleotidase of Testes of Immature Sockeye Salmon (Oncorhynchus nerka)
Authors: Gardner Linda J.
Published: April 2011

Fifty percent of the salmon 5′-nucleotidase is in the soluble fraction after high-speed centrifugation. A threefold purification on a Sephadex G-200 column gives a specific activity of 0.5 μmoles UMP hydrolyzed per hour per milligram of protein. The pH activity curve gives a single peak with an optimum at pH 9.0 MgCl2, CaCl2, and MnSO4increase the activity whereas Zn acetate, Ni acetate, and CoSO4inhibit the enzyme. EDTA, KF 2-mercaptoethanol, and dithiothreitol inhibit the nucleotidase activity. It is stable for up to 1 week at 0 C and up to 2 hr at 35 C, but activity decreases to 50% after 15 min at 50 C and no activity is left after 15 min at 60 C. The nucleotidase shows greatest activity towards 5′-nucleotides; 2′(3′) nucleotides and 5′-deoxynucleotides are hydrolyzed less effectively. Ribose-5-phosphate and p-nitrophenylphosphate are hydrolyzed, but no activity is exhibited against fructose-1-phosphate and α-glycerophosphate.
Depth Distributions of Various Stages of Witch Flounder (Glyptocephalus cynoglossus) off Nova Scotia and in the Gulf of St. Lawrence
Authors: Powles P. M. , Kohler A. C.
Published: April 2011

Larvae, juveniles, and adults of witch flounder off Nova Scotia and in the Gulf of St. Lawrence were found to occupy largely discrete niches. The only larvae found (up to 3.8 cm long and presumed to be under 1 year old) were taken at depths of from 0 to 20 fath (0 to 36 m). Fish newly metamorphosed and up to 30 cm long (5 years old) were caught mainly at 100–160 fath (180–288 m). Adults were taken in summer at 20–150 fath (36–270 m) and in winter at 50–240 fath (90–432 m), suggesting that seasonal movements may take place. The centres of abundance of adults were delineated, but not of larvae or juveniles.It is inferred that the deepwater distribution of young witch flounder prevents direct food competition with young of the more abundant species, cod and American plaice, on the continental shelf areas. Barring unforseen exploitation of the deepwater nursery grounds, witch flounder possess a natural conservation mechanism because of the niche separation between juveniles and adults.
Occurrence of Juvenile and Spawning Atlantic Mackerel in Southeastern Newfoundland Coastal Waters
Authors: Parsons L. S. , Hodder V. M.
Published: April 2011

The capture of juvenile mackerel in Conception Bay, Nfld., during November 1968 represents the first documented record of the occurrence of 0-group mackerel in eastern Newfoundland waters. Their presence suggested the possibility of sporadic mackerel spawning in the area. This was confirmed by the capture of prespawning and spawning mackerel in Placentia Bay during early July 1970.
The Case for Accurate Labeling of Superchilled Fish
Authors: Gould Edith
Published: April 2011

The skeletal muscle of haddock (Melanogrammus aeglefinus) contains a malic enzyme activity that can be solubilized by freezing and thawing the flesh but that is not present in the tissue fluid of unfrozen haddock. An objective test, previously used to detect the presence of this normally latent enzyme activity in the tissue fluid of frozen and thawed fish, has been used to discover whether the latent enzyme appears in the tissue fluid of superchilled fish. Enzymograms for superchilled fish are the same as for frozen fish, both showing the latent enzyme activity that is not present in unfrozen fish. The test underscores the need for precise labeling of superchilled fish.
Muscle Protein Electrophoresis in the GenusSalmoof Eastern Canada
Authors: Gray R. W. , McKenzie J. A.
Published: April 2011

The muscle protein pattern of Atlantic salmon (Salmo solar L.) examined differed markedly from that of brown trout (Salmo trutta L.) and rainbow trout (Salmo gairdneri Richardson). Atlantic salmon muscle proteins from six areas were not influenced by the differences in sex, stage of maturation, or geographical location. The muscle proteins of brown trout taken from two areas in Newfoundland were similar and could not be easily distinguished from that of rainbow trout from Newfoundland. A polymorphism was observed in the pattern of rainbow trout from Great Pond, Nfld. The consistency of the patterns within species suggests that they may provide useful characters for identification purposes.
Relation between Biomass, Productivity, and Loss to Predators in a Population of a Marine Benthic Polychaete, Pectinaria hyperborea
Authors: Peer D. L.
Published: April 2011

The changes in population density and individual size distribution in a population of the trumpet worm Pectinaria hyperborea Malmgren were observed on eight occasions in 20 months at a station 60 m deep on a soft muddy substrate in St. Margaret's Bay, N.S. Production proceeded rapidly during the early life stages while loss due to mortality (elimination) was low, so that biomass increased and reached a maximum at 170 days. Between 30 and 370 days the rate of elimination was nearly constant at about 0.9 g/m2 wet weight per 50-day period in spite of changing biomass. After 370 days the rate of production, rate of elimination, and biomass decreased. It was estimated that 80% of mortality was due to predation. Almost 90% of total production of the cohort took place in the first year of life. The ratio between annual production and biomass present in May 1967 in the study area was used to estimate annual production at 24 stations in the bay.
Zone Electrophoretic Studies on the Proteins of Tilapia mossambica and T. hornorum and their F1 Hybrids, T. zillii, and T. melanopleura
Authors: Chen F. Y. , Tsuyuki H.
Published: April 2011

Starch-gel electrophoretic characteristics of the hemoglobins, muscle myogens, serum transferrins, and serum esterases from two species of mouth brooders, T. mossambica Peters and T. hornorum Trewavas, and two species of substratum spawners, T. zillii Gervais and T. melanopleura Dumeril, are described in detail. The mobility characteristics of lactate dehydrogenases (LDH) from 11 tissues of these four species are also described.The two mouth brooders possess virtually identical LDH zymograms, whereas the unique mobility difference of the skeletal muscle type subunit distinguishes T. zillii from T. melanopleura and from the two mouth brooders. The LDH subunit specific for the eye tissue comprised the major diagnostic feature distinguishing the mouth brooders and the substratum spawners.No mobility differences in serum esterases were found between the two substratum spawners, whereas the mouth brooders did possess different mobilities. Tilapia mossambica possessed a single serum transferrin zone, and T. hornorum one major and one minor zone.The hemoglobins and muscle myogens completely separated all four species of Tilapia indicating that these are the protein groups of choice as diagnostic tools in their identification. These proteins are likewise sufficiently diagnostic to point out that the specimens of T. mossambica and particularly T. hornorum used in these studies were not always biochemically uniform, emphasizing their further value in the selection of parental stocks for breeding purposes. The need for new approaches such as these for supplementing the classical morphometric techniques in fish farming is outlined.
Sex-Related Parental Influences on Early Development of Pacific Salmon
Authors: Withler F. C. , Morley R. B.
Published: April 2011

Among the fertilized eggs arising from a series of intraspecific and interspecific crosses involving sockeye, pink, and chum salmon, time from fertilization to hatching was longest for crosses involving sockeye males, less for those involving pink males, and least for those involving chum males. For crosses of females of the three species with males of a single species, eggs from pink females took longest to hatch, those from sockeye females took less time, and those of chums took the least. Larva size at hatching was greatest for larvae emerging from chum eggs, irrespective of male parent, less for those emerging from sockeye eggs, and least for those from pink eggs. There were only small differences in the size of larvae at hatching from the eggs of females of one species that had been fertilized by males of each of the three species. Among the pre-hatched embryos developing in eggs of a single species, those with a sockeye male parent grew slowest, those with a pink male parent grew faster, and those involving a chum male parent fastest. In eggs from females of the three species fertilized by the males of one species, embryos in eggs of chum females grew fastest, those in eggs of sockeye females slower, and those in eggs of pink females slowest. Gross malformation among hybrid offspring was not pronounced — only chum male × sockeye female and chum male × pink female hybrids displayed markedly greater proportions of malformed individuals than did the combined intraspecific crosses involving the same parents. It is possible that observed differences in time from fertilization to hatching between eggs of different parental origin are brought about by the interaction of growth rates inherited mainly from the male parents and a critical embryo size related to the size of eggs of the female parent. Identification of parental determinants of early development of salmon should make it possible to create salmon forms capable of exploiting new or changed environments.
Chronic Endrin Poisoning in Goldfish,Carassius auratus
Authors: Grant Blake F. , Mehrle Paul M.
Published: April 2011

Endrin incorporated into the diet of mature male goldfish for 3–4 months affected growth, gonad development, thyroid activity, serum characteristics, total and differential body fat, behavior, and mortality. A biphasic response to endrin dosage was characteristic. The low doses (4.3–43 μg/kg body weight per day) either caused no detectable effect or were stimulatory, as seen from increased rates of growth and higher total body fat contents. The two highest doses (143 and 430 μg) caused mortality, lowered growth rates, and other chronic symptoms of endrin intoxication; they also caused decreased thyroid cell heights, decreased gametogenesis, and lowered total body fat, as well as less vacuolization in liver cells.All doses except the highest caused elevated serum Na concentrations. The fish receiving the highest dose suffered osmoregulatory failure. Induced spermiation was not affected; fish receiving 143 or 430 μg/kg had greatly reduced, but functional testes.
Analyses of the Sebastes aleutianus–S. melanostomus Complex, and Description of a new Scorpaenid Species, Sebastes caenaematicus, in the Northeast Pacific Ocean
Authors: Tsuyuki H. , Westrheim S. J.
Published: April 2011

Taxonomic studies, based on biochemical and physical morphology, of the Sebastes aleutianus–S. melanostomus complex (family Scorpaenidae) resulted in the identification and description of new species, Sebastes caenaematicus, whose known range is Cape Flattery, Washington, to Cape Ommaney, Alaska. A synonymy and literature history for the complex is presented.
Distribution, Abundance, and Spawning of Yellowtail Flounder, Limanda ferruginea, in the Newfoundland Area of the Northwest Atlantic
Authors: Pitt T. K.
Published: April 2011

Yellowtail flounder were found as far north as the Strait of Belle Isle; however, the main concentrations were located on Grand and St. Pierre banks. The highest concentrations were found at 31–35 fath (57–64 m) and temperatures of 3.1–4.8 C. Abundance on the Grand Bank apparently increased from 1961 to 1968 coincident with a general upward trend in bottom temperatures and a drastic reduction in the haddock population. The peak spawning period was the latter half of June. Fifty percent of the males were sexually mature at age 5 and 31 cm, and 50% of females at age 6 and 37 cm.
Calanoid Copepods from Midwater Trawls in the North Pacific along 160°E
Authors: Morris Byron
Published: April 2011

Ninety-nine species of calanoid copepods were identified from 29 midwater-trawl samples taken at 10 stations in the subarctic, transitional, and subtropical regions of the North Pacific. Fourteen species are discussed, including the previously unknown male of Gaidius pungens and three species in the Scottocalanus helenae group. There are nine new records of species from the study area.
A Rapid Method for Partial Hypophysectomy in Three Species of Skate (Raja radiata, R. ocellata, and R. erinacea)
Authors: Idler D. R. , Truscott B. , O'Halloran M. J.
Published: April 2011

A rapid and simple method for partial hypophysectomy of batoid elasmobranchs is described. The brain was exposed by an incision in the dorsal surface of the cranium and after removal of the neuro-intermediate lobe, rostral lobe, and saccus vasculosus the incision was sealed with water-compatible tape or adhesive.
RNA–DNA Ratios as Indicators of Recent Growth Rates of a Fish
Authors: Bulow Frank J.
Published: April 2011

When golden shiners (Notemigonus crysoleucas) were fed at 0, 2, and 6% body weight for 15 days, the mean RNA–DNA ratios for defatted tissues (whole, eviscerated fish) were 2.18, 2.83, and 4.32, respectively, in association with mean weight changes of −16.1, 2.2, and 21.3%.Food deprivation for 30 and 45 days resulted in mean ratios of 1.66 and 1.36, in association with mean weight losses of 20.6 and 35.6% body weight. Feeding at 2% body weight for 30 and 45 days resulted in a leveling off of ratios (3.15 and 3.03, respectively) with a continued gain in body weight (19.9 and 45.6%); feeding at the 6% rate for the same durations resulted in a decline in ratios (3.91 and 3.08, respectively) with a continued gain in body weight (57.9 and 90.9%).Depriving golden shiners of food for 14 days and then resuming feeding for 6 days demonstrated that RNA–DNA ratios change rapidly, the changes being attributed primarily to changes in RNA concentrations. Mean ratios declined from 3.56 after 4 days to 2.30 after 14 days of food deprivation. When feeding was resumed, ratios averaged 3.45, 4.93, 5.07, 5.73, 5.00, and 5.14 after 1–6 days feeding, respectively.
A New Species of Prickleback, Bryozoichthys marjorius (Chirolophinae), from the Eastern North Pacific
Authors: McPhail J. D.
Published: April 2011

A new species of stichaeid fish, Bryozoichthys marjorius, is described from the Gulf of Alaska. It differs from the closely related B. lysimus in dorsal spine number, scale pattern, and position of cirri on the head.
Chlorinated Hydrocarbon Insecticide Residues in Winter Flounder, Pseudopleuronectes americanus, from the Weweantic River Estuary, Massachusetts
Authors: Smith Roderick M. , Cole Charles F.
Published: April 2011

Residues of DDT, heptachlor, and dieldrin were found in tissues of winter flounder, Pseudopleuronectes americanus (Walbaum), from the Weweantic River estuary, Massachusetts during 1966–67. In nonmigratory juveniles, seasonal accumulation patterns were demonstrated for DDT, heptachlor, and two related breakdown products, DDE and heptachlor epoxide. Peak concentrations of the parent compounds were more closely associated with high runoff conditions than any specific application in the estuarine drainage. Dieldrin was present uniformly throughout the year.Migratory adult flounder, present only between October and May, contained heptachlor and heptachlor epoxide levels similar to juveniles, but significantly less DDE. Adult female flounder sequentially concentrated DDT, DDE, and heptachlor epoxide in their ripening ovaries as the spawning season approached.
Cardiac and Respiratory Responses to Hypoxia in the Sea Raven, Hemitripterus americanus, and an Investigation of Possible Control Mechanisms
Authors: Saunders R. L. , Sutterlin A. M.
Published: April 2011

Responses of the sea raven (Hemitripterus americanus) to hypoxia consisted of an increase in rate and amplitude of breathing and an increase in dorsal and ventral aortic pressure. Changes in heart rate seldom occurred. Bilateral transection of cranial nerves IX and X resulted in a fall in dorsal aortic PO2 to a sustained low level but did not alter the dorsal and ventral aortic blood pressure or breathing responses induced by hypoxia.Pressure changes in the opercular cavity during breathing seldom exceeded.5 cm H2O and rarely exceeded 1 cm H2O under extreme hypoxia. There were no obvious differences in opercular pressure wave forms before and after bilateral section of nerves IX and X.An artificial "heart-gill" machine was devised with which blood PO2 could be altered outside the fish and the blood perfused into either the dorsal or ventral aorta. Breathing amplitude was increased by perfusing blood of low PO2 into the dorsal aorta. While maintaining dorsal aortic PO2 high and constant, increases in breathing amplitude were induced by low ambient PO2 levels.Vasomotor changes in blood pathways other than the gills probably contribute to the changes in blood pressure observed during hypoxia. Preliminary evidence for both central and peripheral sites of oxygen receptor activity is provided.
Histological Comparisons of the Adrenal-Cortical Cells of Hatchery and Wild Landlocked Atlantic Salmon (Salmo salar)
Authors: Davis Robert M. , Fenderson Owen C.
Published: April 2011

No differences were found in mean diameters of adrenal-cortical cell nuclei between hatchery parr of landlocked Atlantic salmon (Salmo salar) killed immediately after removal from hatchery rearing pools and wild parr electrofished in two streams, and between hatchery and wild parr held for various periods in an outdoor stream aquarium simulating natural conditions. The similarities suggested that the wild and hatchery parr were similar in physiological response to environmental stress. In both hatchery and wild parr, the diameters differed at different times, indicating a downward trend from May to August in the one year of the study. No consistent relation was found between nucleus diameter and social behavior.
A Hypothesis of Alternation of Age of Return in Successive Generations of Skeena River Sockeye Salmon (Oncorhynchus nerka)
Authors: Bilton H. T.
Published: April 2011

Egg weight of Scully Creek and Lower Babine River sockeye salmon (Oncorhynchus nerka) was positively correlated with length and, usually, age of the female parent. Egg weight was positively correlated with initial size and subsequent growth of juveniles, at least up to 3 months of age. Examination of scales indicated juvenile growth in the lake and ocean was inversely related to age at maturity. Hence it was hypothesized that the larger age 1.3 sockeye spawners tend to produce progeny that mature as smaller age 1.2 fish, which in turn give rise to progeny that mature as larger age 1.3 fish, and so on; an alternation in age of return of successive generations occurs.
First Records of Vibriosis in Pacific Salmon Cultured in Canada, and Taxonomic Status of the Responsible Bacterium, Vibrio anguillarum
Authors: Evelyn T. P. T.
Published: April 2011

First proven outbreaks of piscine vibriosis in Canada are recorded. The disease occurred in four species of Pacific salmon that were being cultured in sea water at facilities in Nanaimo and West Vancouver, B.C., and both the disease and the causative bacterium (identified as Vibrio anguillarum) are described.A brief review of the literature on Vibrio fish pathogens suggests that most of these organisms might reasonably be assigned to the species V. anguillarum, and a tentative archtype for the species is described. Before the species is formally recognized, however, a large-scale comparative study is needed to provide the uniform information that is now lacking for individual strains of this species and to determine whether in fact it can be distinguished from other heterotrophic marine vibrios, many of which are commensal with marine animals.
Upper Lethal Temperatures in Relation to Osmotic Stress in the Ribbed Mussel Modiolus demissus
Authors: Waugh D. L. , Garside E. T.
Published: April 2011

Upper lethal temperatures for the ribbed mussel Modiolus demissus (Dillwyn) were determined for thermal acclimations of 15.0, 20.0, and 25.0 C and osmotic acclimations at 5, 15, and 28‰ S, which yielded nine combinations. These upper lethal temperatures for 1440 min exposure ranged from 38.42 to 40.18 C, generally paralleling increases in thermal acclimation. The upper lethal temperature within any thermal acclimation decreased as the salinity of the bioassay departed from the appropriate level of osmotic acclimation. Depression of the upper lethal temperature was more pronounced in the test medium of 5‰ S. The shift from osmoconformity to osmoregulation, which occurs in this species when the ambient salinity is reduced to 350 mosmols (approximately 10‰ S) apparently extends the metabolic load or stress relative to that induced by similar temperatures in higher levels of salinity. Order of death in any bioassay was independent of size expressed as length, and specific sex.The upper lethal temperatures are higher than the mean temperature of the substrate of the collecting site during the warmest period of the summer, but are approximately the same as the maximum substrate temperature during that period. Survival of ribbed mussels in such potentially lethal conditions is explained by the shorter intermittent natural exposures than those employed in the bioassays.
A Key to the Freshwater Hirudinoidea of Canada
Authors: Davies Ronald W.
Published: April 2011

A key to the freshwater leeches (Hirudinoidea) of Canada and the bordering states of the USA is presented, together with notes on their important diagnostic features.
Electrical Responses of the Olfactory Epithelium of Atlantic Salmon (Salmo salar)
Authors: Sutterlin A. M. , Sutterlin N.
Published: April 2011

Multiunit spike activity was recorded from the olfactory mucosa of Atlantic salmon (Salmo salar) using metal-filled glass microelectrodes. A number of simple and complex solutions were tested for stimulatory effectiveness. Amino acids as a class of compounds were highly stimulatory; little or no response was obtained to a variety of simple sugars, n-aliphatic acids, alcohols, or amino-substituted alcohols. An increase in asynchronous spike activity was evoked by low concentrations of amino acids and oscillatory activity was evoked by higher concentrations of amino acids. Brief treatment of the epithelium with dilute solutions of HgCl2 blocked the chemosensitivity of the receptors.
Some Blood Chemistry Values for the Juvenile Coho Salmon (Oncorhynchus kisutch)
Authors: Wedemeyer Gary , Chatterton K.
Published: April 2011

Overlapping Gaussian distribution curves were resolved into normal ranges for 1800 clinical test values obtained from caudal arterial blood or plasma of more than 1000 juvenile coho salmon (Oncorhynchus kisutch) held under defined conditions of diet and temperature. Estimated normal blood chemistry ranges were bicarbonate, 9.5–12.6 mEq/liter; blood urea nitrogen (BUN), 0.9–3.4 mg/100 ml; chloride, 122–136 mEq/liter; cholesterol, 88–262 mg/100 ml;pCO2, 2.6–6.1 mm Hg (10 C); glucose, 41–135 mg/100 ml; hematocrit, 32.5–52.5%; hemoglobin, 6.5–9.9 g/100 ml; total protein, 1.4–4.3 g/100 ml; blood pH (10 C), 7.51–7.83. The calculated range of normal acid–base balance vs. water temperature is also presented.
A Hermaphroditic Specimen of Weathervane Scallop, Patinopecten caurinus, in Alaska
Authors: Hennick Daniel
Published: April 2011

Hermaphroditism in sea scallops is a relatively rare phenomenon. Observations on two hermaphroditic specimens of Placopecten magellanicus have been documented in the literature. Recent studies on the weathervane scallop, Patinopecten caurinus, in Alaska, have resulted in the discovery of a single hermaphroditic individual from sexual examination through dissection of more than 25,000 individuals over a 3-year study period. The specimen appeared to be a functional hermaphrodite, as both male and female follicules containing well-developed eggs and sperms were clearly evident from microscopic examination. Shell examination showed the animal had formed seven annual rings indicating the animal had spawned more than one season, since weathervane scallops mature after formation of the third annual ring.
Concentrations of Dieldrin in the Blood and Brain of the Green Sunfish, Lepomis cyanellus, at Death
Authors: Hogan Roger L. , Roelofs Eugene W.
Published: April 2011

When green sunfish, Lepomis cyanellus, were exposed to concentrations of dieldrin averaging 6 ppb for periods ranging from 124 to 139 hr, the concentrations of dieldrin in the blood and brain at death were approximately 6.0 and 9.0 μg/g. Surviving fish had concentrations markedly lower than those that died. A correlation coefficient of 0.95 was found between concentrations of dieldrin in the blood and in the brain, water dieldrin concentrations having a slight influence on the concentrations in the blood at death. Surviving fish exhibiting severe poisoning symptoms had higher concentrations of dieldrin in the blood and brain than did those showing moderate to minimal symptoms.
World Distribution of Rainbow Trout (Salmo gairdneri)
Authors: MacCrimmon Hugh R.
Published: April 2011

Since 1874, the endemic range of the rainbow trout, Salmo gairdneri Richardson, has been extended through introduction to include eastern North America and the continents of Africa, Asia, Australasia, Europe, and South America. The present range of the species extends into low latitudes by the use of waters at high elevations to over 4500 m above sea level.Environmental factors considered to be of primary importance in the survival of introduced populations are water temperature and precipitation. The presence of suitable spawning grounds, coupled with seasonal water temperatures below 13 C, are essential for the establishment of self-sustaining populations.A further extension of the world range of rainbow trout seems unlikely except perhaps in northeastern Asia. However, distribution within the present range is likely to be increased through the use of new ponds and reservoirs as they are constructed for water supply and flood control by many countries throughout the world. The farming of rainbow trout, now of local significance in parts of eastern Asia, western North America, and central and western Europe, offers an unrealized potential on all continents if warranted by a protein and market demand.
Energy Flow and Secondary Production of the Amphipods Hyalella azteca and Crangonyx richmondensis occidentalis in Marion Lake, British Columbia
Authors: Mathias Jack A.
Published: April 2011

The Hyalella azteca population in Marion Lake, B.C., assimilated and produced about three times as much energy as did the Crangonyx richmondensis occidentalis population from May 1966 to May 1967, but during the summer the energy flow of H. azteca was four times, and production was five times, that of C. r. occidentalis.Hyalella azteca was abundant at a depth of 1.0 m (mean summer standing crop, 1952 animals/m2), but was rare (75 animals/m2) at depths greater than 2.5 m. Growth, molting, respiration, and hence energy flow rates decreased with depth, due (in part) to lower ambient temperatures in deeper water. On an annual basis, a mean standing crop of 1.1 kcal/m2 of H. azteca assimilated 18.1 kcal/m2, respired 13.5 kcal/m2, and used 4.6 kcal/m2 in production of growth, molts, and eggs. Approximately two-thirds of the annual energy flow was completed between June and October. On an annual basis, the ecological efficiency of an H. azteca-predator system was in the range 2.5–12.5%, the net production efficiency was 25%, and the net population growth efficiency was 16%.The mean summer density of C. r. occidentalis remained constant with depth (about 283 animals/m2). Annual energy flow and production were not appreciably affected by lower temperatures in deeper water. On an annual basis, a mean standing crop of 0.7 kcal/m2 assimilated 6.5 kcal/m2, respired 5.2 kcal/m2, and used 1.4 kcal/m2 in production. Crangonyx r. occidentalis energy flow was fairly constant throughout the year. The ecological efficiency of a C. r. occidentalis-predator system was in the range 2–10.5%, the net production efficiency was 21%, and the population growth efficiency was 17% on an annual basis.
Observations on a Colony of Whelping Harbour Seals, Phoca vitulina concolor, on Sable Island, Nova Scotia
Authors: Boulva Jean
Published: April 2011

Three censuses indicated that approximately 1220 harbour seals were at Sable Island at the beginning of whelping in 1970. About 270 pups were born, representing 18% of the total seal population after whelping. Maximum whelping occurred during the last week of May. Males represented 52% of the 118 pups examined. At least 12% of the pups died in the 1st month of life. Pups born with lanugo represented 16% of all pups born. Males and females averaged 80 cm long and 11 kg in weight at birth; 3 weeks later, the males averaged 91 cm and 24 kg and the females 86 cm and 20 kg.
A Rapid Method of Determining Ammonium in Water With a Univalent Cation Glass Electrode
Authors: Barica Jan
Published: April 2011

The use of a univalent cation glass electrode for determining ammonium in water is described. The method enables direct determination of ammonium ion in concentrations above 0.5 mg/liter without any dilution or pretreatment of sample. A constant background of Na+ and K+ in samples is required, with concentration of potassium being lower than that of ammonium. For several types of natural and enriched waters with ammonium content up to 40 mg/liter NH4-N, the mean error by the method was ±4.9%.
Helminth Parasites of Embiotocid Fishes. II. A New Species of Labrifer (Digenea:Lepocreadiidae) from Zalembius rosaceus from California
Authors: Arai Hisao P.
Published: April 2011

Labrifer balli n.sp. from an embiotocid fish, Zalembius rosaceus (Jordan and Gilbert), is described and illustrated. The main features that differentiate the present form from those previously described in the genus are the shape of the body and the position and orientation of the oral sucker.
A Simple Improvement in the Vascular Catheterization Procedure for Salmonid and Other Teleost Fishes
Authors: Houston Arthur H.
Published: April 2011

A simple method is described, by means of which a sharpened hematocrit tube is used as a trocar to assist in the placement of untipped vascular catheters in relatively small fishes with minimum blood loss.
Effects of Washing Freshwater Fish on Keeping Quality
Authors: Gillespie D. C. , Ostovar Kurosh
Published: April 2011

Slime from several freshwater fish species was a good bacteriological medium and supported growth of 109–1010 organisms per gram. Fish stored at 3 C became inedible after several days even though the flesh contained few bacteria. Diffusion of metabolic products resulting from bacterial growth on the slime produced strong odors and flavors in the flesh. Under commercial conditions, washed lake whiteflsh (Coregonus clupeaformis) had lower bacterial numbers and coliform counts and higher organoleptic ratings than unwashed samples.
Analysis of Ammonium–Nitrogen in Artificial Sea water Aquaria
Authors: Ellender Rudolph Dennis , Armour Carl Lee , Camp Bennie Joe
Published: April 2011

A technique for analysis of ammonium–nitrogen in artificial seawater aquaria is described. The method, suitable for measuring ammonium concentrations in the 1–20 μg/ml range, involves diffusion and colorimetry.
Some Physical Oceanographic Features of Inlets of Chile
Authors: Pickard G. L.
Published: April 2011

The first systematic study of physical oceanographic characteristics of the fjord inlets of Chile was carried out by the Institute of Oceanography of the University of British Columbia during March 1970 as Phase V of the Hudson 70 Round-the-Americas Expedition of the Bedford Institute, Canada Department of Energy, Mines and Resources.Observations were made of temperature, salinity, and dissolved oxygen at 175 stations in 32 inlets and in the passages outside them, and soundings were made along 3500 km of track. The sounding data are presented as longitudinal sections, and water properties are summarized in temperature–salinity and temperature–dissolved oxygen correlation plots and characteristic diagrams; comparisons are made with observations for the British Columbia and Alaska inlets reported by Pickard in 1961 (18: 907–999) and 1967 (24: 1475–1506) in the Journal of the Fisheries Research Board of Canada. Observations were also made of nutrients in some Chilean inlets; these will be reported at a later date.In mean and extreme values, the dimensions of the inlets in Chile are similar to those in British Columbia/Alaska; only two shallow sills were recorded. More inlets had glaciers contributing melt water directly to them and more had icebergs present than is the case in the northeast Pacific inlets. Vertical salinity profiles in Chile were similar to those in British Columbia/Alaska, but the thinner surface layer was of higher salinity, except in the inlets having icebergs, and the deepwater salinities were 1–2‰ higher in Chile. Temperatures were 2–5 degrees C higher in Chile except in the iceberg inlets where surface values were lower than those in Alaska. Several of the iceberg inlets in Chile had much more complicated temperature/depth profiles than in Alaska, with as many as seven maxima and minima below the surface. The glacial silt in the inlet waters was more conspicuous and extensive in Chile than in British Columbia/Alaska. Dissolved oxygen values in Chile were much the same as in British Columbia/Alaska with higher values in the iceberg inlets in Chile than in Alaska, and there was little evidence of very low values characteristic of stagnant basins. The lack of low dissolved oxygen values suggests free exchange with outside waters and the inlet deepwater characteristics indicate that the effective sill depths between inlets and the ocean are only 100–150 m deep. At least four distinct major regions are evident from water properties among the inlets of Chile.