摘要：We examined the feeding habit of pond smelt (Hypomesus transpacificus nipponesis) and its impact on the zooplankton community in Lake Suwa, Japan, from May to December 2001. Stomach contents were analyzed, and prey importance and the prey selectivity index were estimated from the stomach contents of fish and prey density in the lake. Results showed that herbivorous zooplankters the cladoceran Bosmina fatalis and the calanoid copepod Eodiaptomus jaonicus were the most important prey items, accounting for about 80% of the total prey biomass in the diet of the pond smelt. However, the selectivity index suggested that pond smelt preferred the predacious cladoceran Leptodora kindtii and the cyclopoid copepod Mesocyclops sp. In the lake, predation impact by pond smelt on the herbivorous zooplankton was not apparent, but the population dynamics of the large invertebrate predators L. kindtii and Mesocyclops sp. seemed to be affected by pond smelt by selective predation.
