Variations in Mean Stomach Content Weights of Walleye Pollock, 'Theragra chalcogramma', in the Eastern Bering Sea

摘要

Variations in mean stomach content weights (as percentage of body weight) of walleye pollock, Theragra chalcogramma, collected in the eastern Bering Sea from 1981 to 1987 were analyzed. The results of a one-way analysis of variance (ANOVA) showed that bottom depth and prey type explained the highest proportions of the total variation in stomach content weights (5.7% and 4.6%, respectively), followed by season and year with 3.8% and 2.8% of the total variation, respectively. In general, the mean stomach content weights were low in the continental slope area and high in the continental shelf area. Walleye pollock that ate both fish and invertebrates had significantly higher stomach content weights than those that ate only invertebrates.