AN INVESTIGATION OF THE LIFE HISTORY AND PROPAGATION OF THE SOCKEYE SALMON (ONCORHYNCHUS NERKA) AT CULTUS LAKE, BRITISH COLUMBIA: No. 3. THE DOWN-STREAM MIGRATION OF THE YOUNG IN 1926 AND 1927

1930 ◽  
Vol 5 (1) ◽  
pp. 55-82
Author(s):  
R. E. FOERSTER PH.D.
Keyword(s):  
British Columbia ◽  
Life History ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Stream Migration

not available

AN INVESTIGATION OF THE LIFE HISTORY AND PROPAGATION OF THE SOCKEYE SALMON (ONCORHYNCHUS NERKA) AT CULTUS LAKE, BRITISH COLUMBIA: No. 4. THE LIFE HISTORY CYCLE OF THE 1925 YEAR CLASS WITH NATURAL PROPAGATION

1933 ◽  
Vol 8 (1) ◽  
pp. 345-355
Author(s):  
R. E. FOERSTER
Keyword(s):  
British Columbia ◽  
Life History ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Spawning Areas

Eggs spawned naturally by 3,883 females in 1925 were estimated as amounting to 17,470,000. Approximately 12,500 fry (0.07% of eggs) migrated to sea in 1926, 183,272 yearlings (1.05%) in 1927, and 1,722 two-year-olds (0.01%) in 1928, making 1.13% in all. Returning fish consisted of no three-year (32 group), 4,463 four-year (42 group), and 1,112 five-year fish (no 52 group, all being of the 53 group). None of the fish was reported returning to other spawning areas.

Fecundity and Egg Retention of Some Sockeye Salmon (Oncorhynchus nerka) Stocks in British Columbia

1986 ◽  
Vol 43 (8) ◽  
pp. 1643-1655 ◽  
Author(s):  
J. I. Manzer ◽  
I. Miki
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Absolute Fecundity ◽  
Egg Retention ◽  
Inadequate Sample Size ◽  
Egg Number ◽  
The Mean ◽  
The Relationship ◽  
Individual Fecundity

The fecundity and egg retention of anadromous female sockeye salmon (Oncorhynchus nerka) collected during 1971–82 from several stocks in British Columbia undergoing controlled fertilization to enhance adult sockeye production were examined. The relationship between egg number and postorbital–hypural length based on 863 females representing 14 stocks was not consistent between all age-types, stocks, and years, probably because of inadequate sample size in some instances. Combined samples, however, revealed a significant positive relationship between postorbital–hypural length and egg number for age 1.2, 1.3, and 2.2 females. Mean absolute fecundity for the respective age-types was 3218, 4125, and 3544 eggs. For samples of 10 or more females, significant stock and annual differences were detected when individual mean absolute fecundity was adjusted to a postorbital–hypural length of 447 mm, but not for females of different age. A comparison of mean fecundities for coastal stocks with historical data for interior British Columbia stocks suggests that coastal stocks are 18% more fecund than interior stocks. Possible causal mechanisms for this regional difference are hypothesized. Examination of 796 carcasses (representing five stocks) for egg retention revealed a range from totally spawned to totally unspawned females, with 56% of the carcasses containing 20 eggs or less and 68% containing 50 eggs or less. The mean egg retention based on all samples combined was estimated to be 6.5% of the mean individual fecundity. This value was reduced to 3.9% when stock means were averaged.

Physiological and Growth Differences in Three Stocks of Underyearling Sockeye Salmon (Oncorhynchus nerka) on Early Entry into Seawater

1994 ◽  
Vol 51 (4) ◽  
pp. 974-980 ◽  
Author(s):  
Stanley D. Rice ◽  
Robert E. Thomas ◽  
Adam Moles
Keyword(s):  
Life History ◽  
Sockeye Salmon ◽  
Salt Water ◽  
Oncorhynchus Nerka ◽  
Early Life History ◽  
Life History Strategies ◽  
Growth Differences ◽  
The Impact ◽  
Lake Type ◽  
River Type

We compared the impact of exposure to seawater on three sockeye salmon (Oncorhynchus nerka) stocks: one that normally migrates to sea as underyearlings (sea-type) and two with the more common life history strategies of 1 (river-type) or 2 (lake-type) yr of freshwater residence prior to seaward migration. Innate differences in survival, ability to regulate tissue chlorides, and oxygen consumption when first introduced into salt water were more evident in April and May when fish were less than 50 mm in length. In fish longer than 50 mm, the only significant differences among the stocks were in saltwater growth. Between June and August, sea-type fish showed faster growth than river-type fish which in turn grew faster than lake-type fish. When introduced into salt water in October, virtually no growth occurred in any stock, regardless of fish size. River-type and lake-type sockeye, which normally overwinter 1 and 2 yr, respectively, in freshwater, can be reared in seawater if underyearlings are raised to a length of 50 mm before release into salt water, similar to the normal life history of sea-type underyearlings. Early life history appears to be influenced more by habitat than by genetics.

scholarly journals Importance of sample size for estimating prevalence: A case example of infectious hematopoietic necrosis viral RNA detection in mixed-stock Fraser River Sockeye salmon (Oncorhynchus nerka), British Columbia, Canada.

2020 ◽  
Author(s):  
Emilie Laurin ◽  
Julia Bradshaw ◽  
Laura Hawley ◽  
Ian A. Gardner ◽  
Kyle A Garver ◽  
...  
Keyword(s):  
British Columbia ◽  
Sample Size ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Small Sample ◽  
Viral Rna ◽  
Sample Sizes ◽  
Apparent Prevalence ◽  
Infectious Hematopoietic Necrosis ◽  
Mixed Stock

Proper sample size must be considered when designing infectious-agent prevalence studies for mixed-stock fisheries, because bias and uncertainty complicate interpretation of apparent (test)-prevalence estimates. Sample size varies between stocks, often smaller than expected during wild-salmonid surveys. Our case example of 2010-2016 survey data of Sockeye salmon (Oncorhynchus nerka) from different stocks of origin in British Columbia, Canada, illustrated the effect of sample size on apparent-prevalence interpretation. Molecular testing (viral RNA RT-qPCR) for infectious hematopoietic necrosis virus (IHNv) revealed large differences in apparent-prevalence across wild salmon stocks (much higher from Chilko Lake) and sampling location (freshwater or marine), indicating differences in both stock and host life-stage effects. Ten of the 13 marine non-Chilko stock-years with IHNv-positive results had small sample sizes (< 30 samples per stock-year) which, with imperfect diagnostic tests (particularly lower diagnostic sensitivity), could lead to inaccurate apparent-prevalence estimation. When calculating sample size for expected apparent prevalence using different approaches, smaller sample sizes often led to decreased confidence in apparent-prevalence results and decreased power to detect a true difference from a reference value.

Infectious agent detections in archived Sockeye salmon (Oncorhynchus nerka ) samples from British Columbia, Canada (1985-94)

2019 ◽  
Vol 42 (4) ◽  
pp. 533-547 ◽  
Author(s):  
Krishna K. Thakur ◽  
Raphaël Vanderstichel ◽  
Karia Kaukinen ◽  
Omid Nekouei ◽  
Emilie Laurin ◽  
...  
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Infectious Agent

Recent Colonization of a Major Salmon-Producing Lake in British Columbia by Pacific Lamprey (Lampetra tridentata)

1984 ◽  
Vol 41 (2) ◽  
pp. 278-285 ◽  
Author(s):  
Susan P. Farlinger ◽  
Richard J. Beamish
Keyword(s):  
British Columbia ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Nursery Area ◽  
Commercial Fishery ◽  
Rock Slide ◽  
Pacific Lamprey ◽  
Natural Lake ◽  
Lampetra Tridentata

Pacific lamprey (Lampetra tridentata) were first observed in Babine Lake, the largest natural lake wholly contained in British Columbia, in 1963 and are currently found along approximately 15% of the length of the lake near the outlet. The number of spawning adults in 1982 was estimated to be 7281. Since Babine Lake is a major nursery area for sockeye salmon (Oncorhynchus nerka), the colonization of this lake by a parasitic lamprey is of concern, particularly if the species can become nonanadromous. The colonization may be beneficial if a commercial fishery can be sustained and if the species does not begin to feed in freshwater. The reason for the recent colonization is unknown but it coincides with increased human manipulation of fishes and habitat, including the removal of a major rock slide, 65 km downstream of the lake.

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