2016 Volume 80 Issue 3 Pages 222-230
The distribution and occurrence of cold water masses on the south side of the Kuroshio Current was examined in relation to the formation of fishing grounds for migrating skipjack. Fishing range of skipjack inshore pole fishery is formed in areas with sea surface temperatures lower than 19°C. To the south of the Kuroshio Current in spring, cold water mass with a sea surface temperature lower than 19°C sometimes stretches from the area north of 28°N, the Boso offing, to around 133°E of the Shikoku offing. Therefore, in years when a cold water mass occurred it was observed that the northward migration of skipjack was either blocked or bypassed the cold water mass. The northward migration course of skipjack and the time remaining in areas during its northward migration can be predicted from the water temperature on the south side of the Kuroshio Current during spring.
