Variation in developmental biology of pink salmon (Oncorhynchus gorbuscha) in British Columbia

Abstract

Pink salmon stocks in British Columbia spawning from August through October were surveyed for variation in developmental biology from 1983 to 1985. Pink salmon in the even-year broodline tended to have higher embryonic survival and proportionately better embryonic and alevin growth at a low incubation temperature (4 °C) than did those in the odd-year broodline. Within a broodline, late-spawning stocks had slightly faster fry emergence timing than did early spawning stocks. Stocks within broodlines had different trends in alevin and fry size with respect to incubation temperature. Pink salmon in the even-year broodline appeared to be better adapted to a colder environment than those in the odd-year broodline. This may reflect a different recent origin of the two broodlines.