Meristic and morphometric variation in pink salmon ( Oncorhynchus gorbuscha ) in southern British Columbia and Puget Sound

• Published in: Canadian Journal of Zoology
• Main Author: Beacham, Terry D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1985
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Oncorhynchus gorbuscha; Pink salmon
• Online Access: http://dx.doi.org/10.1139/z85-056; http://www.nrcresearchpress.com/doi/pdf/10.1139/z85-056

Variation in the number of gill rakers and four morphometric characters was examined for 4 stocks from the even-year brood line and 20 stocks from the odd-year brood line of pink salmon (Oncorhynchus gorbuscha) in southern British Columbia and Puget Sound. Significant differences in gill-raker frequencies were observed among stocks within each brood line, but differences were greater between the brood lines than within each brood line. Sizes of the morphometric characters standardized to a body length of 419 mm were also variable among stocks within a brood line, but stocks spawning in rivers in the same region in alternate years were more similar morphometrically than to those spawning in different regions. It is suggested that patterns of meristic and morphometric variability are reflective of genetic differences, with meristic variability illustrating the genetic differences between the brood lines, and morphometric variability reflecting adaptation to local water velocity conditions in the streams the stocks return to during spawning.