日本海における雄ズワイガニの漁獲サイズ

概要

論文の詳細を見る
The legal minimum size of male snow crab Chionoecetes opilio has been defined as 90mm carapace width regardless of the terminal molt in the Sea of Japan. However, the multiparous females mate with the terminal molt males, so it is questionable whether sufficient males can be expected under present fishing conditions. In this study, the sex ratio (the number of terminal molt males with hard-shell to the number of multiparous females) was estimated for a variety of minimum sizes and fishing intensities. Assuming that the sex raio 0.47 at no fishing might be reasonable, an optimum carapace width was proposed.Thus, at present fishing intensity for both sexes, the minimum size of male carapace width was estimated at 95-100mm, and at one-half fishing intensity for females the size was estimated at 100-110mm. By increasing the estimated size, 95-100mm and 100-110mm, simultaneously, it was ascertained that catch values of males might increase by 6-14%, 10-20%, respectively, due to the decrease of soft-shell and pre-terminal molt crabs.
1996-07-15