摘要:

The life cycles and vertical distributions ofLimnocalanus macrurusandSenecella calanoidesand the seasonal abundance and vertical distributions of adults of other planktonic copepods in Parry Sound, Georgian Bay, were determined from diurnal vertical plankton hauls taken on 14 occasions from June 19, 1967, through November 11, 1968. The most abundant cyclopoid copepod on most occasions wasCyclops bicuspidatus thomasi.Tropocyclops prasinuswas common, particularly in summer and autumn.Mesocyclops edaxandCyclops vernaliswere scarce.Cyclops bicuspidatus thomasiandT.prasinuswere usually concentrated in the upper strata,T.prasinusseldom being deeper than 3 m during summer.The most abundant calanoid copepod wasDiaptomus ashlandi.Diaptomus minutusandD.oregonensiswere also common, butD.siciliswas rare.Diaptomus ashlandiandD.oregonensisoccupied much the same depths in the metalimnion during the periods of thermal stratification but were deeper in spring and fall.Diaptomus minutuswas concentrated mainly in the epilimnion even when thermal stratification was slight.Epischura lacustrisandEurytemora affiniswere scarce.Limnocalanus macruruswas abundant and monocyclic, becoming adult in late spring but not spawning until autumn; older copepodites inhabited somewhat deeper strata than younger stages.Senecella calanoideswas less abundant thanL.macrurusbut was also monocyclic, becoming adult in autumn and spawning almost immediately; all instars were usually found in deeper water thanL.macrurus. The possibility thatS.calanoides, because of its longer period of development, is better adapted to life in Parry Sound thanL.macrurusis discussed.

ISSN:0706-652X    

DOI:10.1139/f69-250

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

Measurements of length, girth, and weight show that male white whales grow larger than females. The smallest white whales come from western Hudson Bay, the White Sea, and Bristol Bay, Alaska. Animals of intermediate size inhabit all other arctic Canadian localities sampled and also the St. Lawrence River and the Kara and Barents seas. The largest white whales inhabit West Greenland waters, the Okhotsk Sea, and the coast of Sakhalin. Extreme differences in body weight of adult males are about threefold. Nonoverlapping differences in size indicate isolation of some adjacent populations of white whales; equal or overlapping sizes suggest, but cannot prove, mixing of other populations. Size can be positively correlated with marine productivity, being lowest in the arctic and in estuaries and highest in subarctic seas. Since white whales most often grow largest at the southern ends of their range, their restriction to the arctic is attributed either to competition with certain of the Delphinidae or to predation from killer whales,Orcinus orcaL., or to both. Both putative competitors and predator lack adaptations for arctic life.

ISSN:0706-652X    

DOI:10.1139/f69-251

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

The KB corer has many advantages over other bottom-sampling devices including some other coring tubes. It may be used to obtain reliable estimates of the standing stock of benthic invertebrates inhabiting soft sediments and of their spatial distribution in lakes and rivers. It may also be used for studies of the vertical distribution of animals and bacteria, and could be used for a wide variety of studies on sediments. Multiple-unit versions have been built and operated, thus overcoming the size limitation imposed by the basic design. This paper communicates some results obtained using this sampler.

ISSN:0706-652X    

DOI:10.1139/f69-252

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

AcrocirrusGrube andMacrochaetaGrube (Polychaeta Sedentaria), comprising at present 14 species, are removed from the Cirratulidae and placed in a new family. The descriptions of the type species of the genera and of five other species are materially improved.Acrocirrus trisectusandMacrochaeta pegeare newly described;Acrocirrus heterochaetus okotensisImajima is elevated to species rank. Diagnoses and records as well as keys for identification are given for all species of the family.

ISSN:0706-652X    

DOI:10.1139/f69-253

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

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

ISSN:0706-652X    

DOI:10.1139/f69-254

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

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

ISSN:0706-652X    

DOI:10.1139/f69-255

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

The rationale for employing a nonlinear iterative least-squares technique for fitting the well-known power function to oxygen consumption–body weight data is set forth. Twenty-six sets of routine or standard metabolism data from six authors were used to demonstrate the relative merits of two methods of calculating parameter values for the power function. The conclusion was reached that if accuracy in predicting oxygen consumption over a wide range of values of body weight is desired, an iterative curve fitting method may be superior to the much used technique of performing a linear regression on logarithmically transformed data.

ISSN:0706-652X    

DOI:10.1139/f69-256

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

Ethylenediaminetetraacetic acid (EDTA) used in 1% solution as a dip extended the 0.5-C shelf life of petrale sole and ocean perch fillets by repressing growth ofPseudomonasspoilage organisms and formation of trimethylamine. Of the three salts compared, Na2EDTA and Na4EDTA were the most effective, extending shelf life of ocean perch fillets by 7–10 days, whereas Na2CaEDTA gave a 4-day extension over the control fillets. Vacuum packaging enhanced the effectiveness of EDTA as a preservative.

ISSN:0706-652X    

DOI:10.1139/f69-257

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

Eight heterotrophic aerobic bacteria were identified in samples from Toronto Harbour. The three tubificid species present seem to ingest most if not all of these, but different species survive passage through the gut. One of the three worm species absorbs amino acid from solution in the absence of bacteria in the gut. It is suggested that the results indicate differences in the utilization of the potential nutritional resources by the worms, which may be reflected in the ability of three unspecialized sediment feeders to coexist in the same microhabitat.

ISSN:0706-652X    

DOI:10.1139/f69-258

出版商:NRC Research Press    

年代:1969

数据来源: NRC

摘要:

Histological, histochemical, biochemical, and ultrastructural studies show that digestion inSyndesmis franciscana(Lehman, 1946), a rhabdocoel entocommensal in the coelom and intestine of the sea-urchinStrongylocentrotus purpuratusfrom California, is both extra- and intracellular, involving an endopeptidase, exopeptidases, phosphatases, and a lipase. The gastrodermal cells are loaded with lipid globules, so that this substance forms over 25% of dry weight. Glycogen accounts for a further 19% dry weight. Over 85% of the glycogen is in the solublelyo-form, as in adult endoparasitic helminths. Both the form and total amount of glycogen present suggest that the pattern of carbohydrate metabolism is more akin to the parasitic than the free-living platyhelminths.Syndesmis antillarumStunkard and Corliss, 1951, a syndesmid from the Caribbean, is shown to differ both morphologically and physiologically fromS.franciscana. The present synonymy of these two species is considered unjustified and incorrect.

ISSN:0706-652X    

DOI:10.1139/f69-259

出版商:NRC Research Press    

年代:1969

数据来源: NRC