Effects of climate change on the catch fluctuation of abalone Haliotis discus hannai in each area of the coast of Hokkaido, Japan

Abstract

　Effects of climate change on the long-term fluctuation in the catch of abalone Haliotis discus hannai along the west and south coasts of Hokkaido, the northern limit of its distribution, were examined. The trend of fluctuation index (TFI) for the transformed abalone catch (Catch-TFI) showed a negative correlation with TFI for Aleutian Low Pressure Index (ALPI-TFI) in the northern Japan Sea Coast. Catch-TFI in the southern Japan Sea Coast presented positive correlations with the ALPI-TFI, and showed negative correlations with the TFI for the Arctic Oscillation Index (AOI-TFI), the same as the western Tsugaru Strait Coast. Changes in sea water temperature in winter controlled by climate change appear to affect the fluctuation of abalone fishery resource in various ways depending on the area on the coast of Hokkaido, through the survival rate of juvenile abalone and seaweed production affecting the egg production of adult abalone.