1999 Volume 54 Pages 14-23
From August 1993 to June 1994, the feeding habits of fishes and distribution of benthos were investigated off the coast of Usujiri, Hokkaido. Most of the 30 fish species sampled fed on benthic crustaceans: cumaceans, isopods, caprellideans, macrurans, and especially gammarideans and mysidaceans. The population of some dominant crustaceans dramatically varied depending on season and water depth; in shallow sea-grass beds in summer, their population exploded. Additionally if life-form categories are considered free-living surface dwellers comprised the principal diet for most fish species. Phytal animals, nest builders and epifaunal tube dwellers, infaunal dwellers, and nekton were also well represented in the stomach contents of fishes. Whittaker's percentage similarity (PS2) of stomach contents was relatively high on average among feeders on mysids or free-living surface-dwelling gammarideans, which appeared in shallow areas in summer. In contrast, the PS2 of stomach contents was consistently low between polycheate feeders and other fish species.
