Effect of the kuroshio on the spatial distribution of the red flying squid Ommastrephes bartramii in the Northwest pacific Ocean

As a dominant current in the northwest Pacific Ocean, the Kuroshio influences the population dynamics and species distributions in this region. Using catch per fishing day (CPU E, t/d) of the red flying squid Ommastrephes bartramii (LeSueur, 1821) from the Chinese mainland squid jigging fleets on the feeding ground (150°E-165°E, 38°N-46°N) from August to October of 1998-2007, we calculated the monthly latitudinal center of gravity of CPU E (LATG _j) and analyzed the relationship between the strength and position of the Kuroshio and the spatial distribution of O. bartramii. The LATG _j for this species differed significantly from month to month. Regression modeling of the LATG vs Kuroshio transport also revealed a significant influence of Kuroshio strength on the north-south movement of O. bartramii. We suggest that the varying strength of the Kuroshio leads to changes in environmental conditions at 150°E-155°E, 40°N-43°N. The environmental variable most significantly correlated with LATG _j was sea surface temperature, suggesting that the distribution of O. bartramii is controlled by optimal thermal habitat. We conclude that the spatial distribution of O. bartramii on their feeding grounds from August to October can be forecast using the path and transport of the Kuroshio.