1990-91～91-92年の岩内湾におけるスケトウダラ Theragra chalcogramma (Pallas) 卵稚仔の分布動向と最近の特徴

• Main Authors: 八木 宏樹, 武藤 卓志, Yagi Hiroki, Mutoh Takashi
• Format: Article in Journal/Newspaper
• Language: Japanese
• Published: 北海道立中央水産試験場 1993
• Subjects: 660; 水産学; Theragra chalcogramma
• Online Access: https://barrel.repo.nii.ac.jp/?action=repository_uri&item_id=3716; http://hdl.handle.net/10252/4284; https://barrel.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3716&item_no=1&attribute_id=19&file_no=1

The distribution patterns of eggs, larvae and postlarvae of the walleye pollock Theragra chalcogramma (Pallas) observed in the seasons of 1990-91 to 91-92 in the Iwanai Bay (Japan Sea) were analysed and compared with that of 1986-1987 to 89-90. The maximum level of the eggs, larvae and postlarvae occurred in 1989-90 for recent years, whereas the lowest levels were shown in 1991 to 92 followed by 1987-88. Since the season 1991-92 corresponds to the recruitment season of the 1987-88 spawning population. We suggest that there is some relation between the parent and its progeny stocks in spite of the hypothesis that there is rare numerical relation between them for this species. We also discussed the advanced spawning season in 91-92 in comparison with the previous seasons and relation to the low level abundance of eggs due to over harvesting.