カタクチイワシ太平洋系群と対馬暖流系群の資源動態と変動の要因

摘要

The aim of this paper is comparing environmental factors for affecting recruitment of Japa-nese anchovy in the Pacific Ocean and Tsushima Warm Current region. The catch of anchovy in the both areas was low level in the 1980s, and increased in the 1990s, and stayed in the high level or decreased in the 2000s. It is well known that there are species alternation between anchovy and sardine around sea waters of Japan, and the recruitment fluctuations of the both species were affected by the environmental factors. We analyzed the correlations between logarithmic recruitment residuals (LNRR) and environ-mental factors in winter. LNRR of Pacific Ocean stock and Tsushima Warm Current stock were signifi-cantly correlated with PDO (Pacific Decadal Oscillation) and deviation of 50 m water temperature in the western Sea of Japan, respectively.