Growth after the spring peak in the third year at sea was relatively low during 1977-2000.
During 1977-2000, when salmon abundance was relatively great, sockeye salmon growth was high during specific seasons compared with that during 1955-1976, that is to say, immediately after entry to Bristol Bay, after peak growth in the first year, during the middle of the second growing season, and during spring of the third season. The alternating odd and even year growth pattern was consistent before and after the 1977 ocean regime shift. However, reduced scale growth in odd-numbered years began after peak growth in spring and continued through summer and fall even though most pink salmon had left the high seas by late July (10-18% growth reduction in odd vs. Total second and third year scale growth of salmon was significantly lower during odd- than during even-numbered years. smolts was significantly higher than age-1 smolts.
First year scale growth was not significantly different between odd- and even-numbered years, but peak growth of age-2. Here we evaluated seasonal growth trends of Kvichak and Egegik river sockeye salmon (Bristol Bay stocks) during even- and odd-numbered years at sea by measuring scale circuli increments within each growth zone of each major salmon age group between 19. Recent research demonstrated significantly lower growth and survival of Bristol Bay sockeye salmon (Oncorhynchus nerka) during odd-numbered years of their second or third years at sea (1975, 1977, etc.), a trend that was opposite that of Asian pink salmon (O.
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