Comparisons of the Index of Return for Several Stocks of British Columbia Salmon to Study Variations in Survival

The "index of return" (ratio of offspring catch to parent catch) was used to compare annual survival among several stocks of British Columbia salmon. Over a period of almost 30 years the major stocks of pink salmon in the Province, excepting those of the Fraser River, exhibited quite simil...

Full description

Bibliographic Details
Published in:Journal of the Fisheries Research Board of Canada
Main Author: Godfrey, H.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1958
Subjects:
Online Access:http://dx.doi.org/10.1139/f58-050
http://www.nrcresearchpress.com/doi/pdf/10.1139/f58-050
Description
Summary:The "index of return" (ratio of offspring catch to parent catch) was used to compare annual survival among several stocks of British Columbia salmon. Over a period of almost 30 years the major stocks of pink salmon in the Province, excepting those of the Fraser River, exhibited quite similar annual variations in survival. The Fraser River stock behaved somewhat independently of the other stocks. There are indications that among pink salmon early ocean survival, probably during residence in estuarial and inshore waters, has played a major role in determining the level of final ocean survival. Among pink and sockeye salmon that entered the sea in the same year there is some similarity in early ocean survival. The latter relationship, if confirmed, may become useful for predicting sockeye ocean survival one or two years before the adult fish return.