レジームシフトによるスルメイカの資源水準および生態の変化

摘要

In this study, for a better understanding of the influence of regime shifts on the trend of stock size of Japanese common squid, variability in the stock size with regime shift, changes in the spawning grounds and migration pattern that coincided with regime shifts were summarized. Paralarval density in the Tsushima Strait was very low level during 1980s but it increased abruptly in 1989 and the spawning grounds of the autumn-spawning stock shifted coincided with 1988/89 regime shift. We can predict the trend in stock size of Japanese common squid by observing these changes in ecological properties, and this can be used to implement appropriate management strategy plans.