Habitat segregation by fishes in western Taiwan rivers

摘要: Summary Habitat segregation has been recognized as an important means of resource partitioning in river fish assemblages. Association between fishes and habitat features were identified through principal component analysis (PCA). Fish data collected the Kaoping, Tsengwen, Choshui, Tatu rivers from July 1997 to June 1999 western Taiwan. Electrofishing was used collect grids, environment variables sampled areas measured immediately after sampling. The first four PCs depth, velocity, cover, substrate water temperature explained 92.3% total variance characteristics. Varicorhinus barbatulus, Acrossocheilus formosanus Tilapia mossambica upper right quadrant, indicated preference for deep-water habitat. Species usually associated with shallow include several minnow species. Rhinogobius brunneus, Hemimyzon formosanum, Sinogastromyzon puliensis Crossostoma lacustre distribution is centred lower left, indicating water. Principal (PC) scores on Zacco pachycephalus, Abbottina brevirostris Hemiculter leucisculus appeared have no special preference. Differences use exhibited by these species may be related success finding food avoiding predators.