Long-term changes in the diet of Gymnogobius isaza from Lake Biwa, Japan: effects of body size and environmental prey availability.

Body size and environmental prey availability are both key factors determining feeding habits of gape-limited fish predators. However, our understanding of their interactive or relative effects is still limited. In this study, we performed quantitative dietary analysis of different body sizes of goby (Gymnogobius isaza) specimens collected from Lake Biwa between 1962 and 2004.