Body Size of Maturing Chum Salmon in Relation to Sea Surface Temperatures in the Eastern Bering Sea

摘要

During their last season at sea, some chum salmon from North America and Japan are known to forage in the southeast Bering Sea. Body size of mature chum salmon from North America and Japan was compared with sea surface temperatures in the winter, spring, and summer in the southeast Bering Sea during three time periods: pre-regime shift 1960-76, regime shift 1977-94, and post-regime shift 1995-2006. During the 1977-94 time period, mean correlation coefficients between body size and sea surface temperatures were positive and largest during the winter and spring. During the 1960-76 and 1995-2006 time periods, correlation coefficients were usually smaller and often negative. We conclude that chum salmon from many locations around the Pacific Rim were present in the eastern Bering Sea during the winter and spring of 1977-1994. We suggest that differences in oceanographic parameters and population density of salmon during the three time periods may influence migration pathways of salmon in the North Pacific Ocean and Bering Sea. Research on migration patterns of salmon in relation to these factors is necessary to elucidate these issues.