5. Conclusions
The non-native fish species composition in eight rivers of South China is clearly related to their introduction use, which correlates to their biological characteristics, particularly their ecological trophic position and compatibility with their native habitat. The predacious and omnivorous non-native fish species used in aquaculture are able to successfully survive in South China’s rivers, especially those species native to tropical regions. Geographical isolation and temperature affected the non-native fish species composition, numbers of species, and dominant species in the region, and these two factors probably most influence the differences in their distributions.