To investigate the presence of exotic non-native fish species in streams in Handa City, we caught fish in four streams from July to August 2002. We also investigated the change in species composition by comparison with data from 1994 to 2002. We caught three exotic species, Micropterus salmoides, Lepomis macrochirus and Pseudorasbora parva. M. salmoides showed a tendency to increased numbers from 1999 and this increase seems to be related to decreases in populations of some native fish species during the same time span
