摘要:

Four oceanographic surveys of the Pacific Ocean between the Canadian coast and Longitude 141° W. were undertaken in 1950, 1951 and 1952. The data are analysed to show the temperature, salinity and density structure, and the calculated currents. There isasurface zone about 100 to 150 metres deep in which all seasonal variations occur. This overlies a lower zone of more saline water of constant properties. The currents are weak and sinuous. It appears from these data and comparison with other work that the region lies in the divergence of the Sub-Arctic Current which divides to form the north-flowing Alaska Gyral and the south-flowing California Current. The identity and origins of the water masses are discussed.

ISSN:0706-652X    

DOI:10.1139/f55-001

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Seasonal and regional variations in the abundance of albacore during the 1949, 1950 and 1951 British Columbia fishing seasons suggest that exploitable stocks occurred in increasingly northerly areas during July and August and in more southerly areas during late August, September and early October. Catches were composed of four length-groups with average lengths of 54.3, 62.9, 71.7 and 81.9 centimetres. These groups were sometimes fairly discrete, but usually overlapped broadly, so that it was necessary to plot frequency distributions on probability paper in order to choose the best points of separation.Concentric marks on the centra of vertebrae were used as indicators of the age of the fish. The relationship of body length to vertebral radius is rectilinear. There is good agreement between the estimated average length and standard deviation in length of the fish when grouped by length and when grouped by vertebral ring number. The ages indicated for the four groups are III, IV, V and VI; however the first vertebral ring is somewhat less clear than the others and if it were discounted these ages would be reduced by one year. The fish whose vertebrae were examined had almost completed a year's growth.The length-weight relationship is expressed by the formula, log W = −4.912 + 3.13 log L, where W is the weight in kilograms and L is the fork length in centimetres.

ISSN:0706-652X    

DOI:10.1139/f55-002

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Sections of testes and ovaries from 44 fish showed maturing individuals in age-groups V and VI, but none in IV. There was no evidence of previous spawning.

ISSN:0706-652X    

DOI:10.1139/f55-003

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The mechanical drying of lightly salted fish must be carried out by successive drying periods and press-piling. This procedure considerably reduces the drying time. Best results are obtained at a temperature of 80°F., and at an air velocity of 300 to 400 linear feet per minute. The relative humidity of the drying atmosphere should be maintained at about 50–55 per cent during the first drying period and 60–65 per cent during all subsequent ones. The first drying period should be of sufficient length to reduce the moisture content of the fish to about 55–60 per cent. The operation is then completed by successive 12-hour drying periods. Cross-piling during the press-piling period is important as it gives a product of better quality.

ISSN:0706-652X    

DOI:10.1139/f55-004

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Extracts of post-rigor cod muscle made at low ionic strength have been examined by electrophoresis in sodium chloride phosphate buffers of ionic strength 0.15 (NaCl = 0.10) and pH between 5.3 and 7.5. The patterns were qualitatively similar to those reported for extracts made from freshly killed cod. At the lower pH values, ten components could be distinguished. The highest isoelectric point found was at pH 5.9, much lower than those reported for similar proteins from rabbit.

ISSN:0706-652X    

DOI:10.1139/f55-005

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Correlation methods were employed in a statistical analysis of the relation between catch fluctuations and economic factors for the principal Canadian commercial species of the Atlantic and Pacific coasts. The results indicate that the major part of catch fluctuations are ascribable to economic factors in the cases of Atlantic herring, "sardines", and cod (tentative), and Pacific herring. Economic factors appear to have had no significant effect on the catches of Atlanta lobsters and Pacific halibut and salmon.

ISSN:0706-652X    

DOI:10.1139/f55-006

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Of the 1-year-old sockeye (Oncorhynchus nerka(Walbaum)) smolts migrating from Babine Lake in 1952 and 1953, in each year about 35% were infected with the cestodeEubothrium salvelini(Schrank, 1790) and 20% by the nematodePhilonema oncorhynchiKuitunen-Ekbaum, 1933. Six to 7% of the smolts harboured both parasites. Fish infected by cestodes only or cestodes and nematodes were significantly smaller than uninfected fish or those with nematodes only. This indicates that the cestode infection retards growth. Nematode-infected smolts were significantly larger than the uninfected individuals in 1952 but not so in 1953.

ISSN:0706-652X    

DOI:10.1139/f55-007

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The following helminth parasites have been recorded from Cetacea caught off the British Columbia coast. Trematoda:Lecithodesmus goliath(fin whale),Lecithodesmus spinosusn. sp. (sei whale) andOgmogaster plicatus(fin and sei whales); Cestoda:Phyllobothrium delphini(sperm and fin whales); Nematoda:Anisakis simplex(sei, Baird's beaked and sperm whales),Anisakis physeteris(sperm whale), immatureAnisakissp. (fin and humpback whales) andCrassicauda pacifican. sp. (fin whale); Acanthocephala:Bolbosoma turbinella(sei whale).Crassicauda pacificaandL.spinosusare illustrated and described, and compared with known species of their respective genera. The variations in morphology and measurements are discussed forO.plicatus. Notes on host and geographical distribution are cited for all parasites.Lecithodesmus goliathandO.plicatusare reported for the first time from the Pacific andP.delphiniwas previously unknown in the North Pacific.Bolbosoma turbinellais a new record for the northeast Pacific andA.physeterisfor the Pacific coast of Canada. Baird's beaked whale and possibly the sperm whale are new host records forA.simplex. The fin whale is a new host record forP.delphiniandL.goliath.

ISSN:0706-652X    

DOI:10.1139/f55-008

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Maxilliped palps are present in adultCyamus ceti,C.scammoniandC.ovalis; absent in adultC.boopis,C.nodosusandC.gracilis; their presence is variable inC.erraticusandC.catodontis. The genusParacyamusis considered a direct synonym ofCyamus.Neocyamusn. gen. is created for the acceptance ofCyamus physeterisPouchet.Cyamus elongatusHiro is shown to be a synonym ofC.boopisLütken andC.boopisvar.physeterisPouchet is a synonym ofC.catodontisMargolis. Further notes on the morphology of several species of cyamids are presented.

ISSN:0706-652X    

DOI:10.1139/f55-009

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Observations on the metal used as pins for Petersen-type tags onParophrys vetulusshowed manufactured nickel pins to be most subject to corrosion or wear, with pins of silver wire, nickel and stainless steel wire successively less liable. Tagging wounds were worst with nickel pins and least with stainless steel wire. A correction factor of approximately 1.7 for each year the tag is out is necessary to bring results with nickel pins on a par with those of stainless steel wire.

ISSN:0706-652X    

DOI:10.1139/f55-010

出版商:NRC Research Press    

年代:1955

数据来源: NRC