神奈川県横浜市港北区の鶴見川における特定外来生物ブルーギル（スズキ目：サンフィッシュ科）の食性

抄録

The bluegill Lepomis macrochirus, an invasive alien fish species, has been confirmed in the Tsurumi River in Kanagawa Prefecture, Japan. To investigate the impact of the bluegill on native species in terms of predation and competition, the stomach contents of the bluegill captured in the Tsurumi River were analyzed. Invertebrates predominated the stomach contents and no fish species was observed, in which larvae of the insect family Chironomidae were the most abundant, followed by an amphipod Crangonyx floridanus and an insect Micronecta sahlbergii. These results suggest that the bluegill may be exerting a foraging influence on native species.