Habitat use by fish species in the Hapen Creek of northern Taiwan

• Main Authors: Ling-Chuan Chuang, 莊鈴川
• Other Authors: 林曜松
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/08507797122940907562

博士 === 國立臺灣大學 === 生態學與演化生物學研究所 === 92 === Ecomorphology of two common cyprinid fishes, Varicorhinus barbatulus and Candidia barbatus, and habitat use of two common endemic and benthic fishes, Crossostoma lacustre and Rhinogobius candidianus, were investigated in the Hapen Creek of northern Taiwan from August 1996 to December 1998. Results showed that C. barbatus, that had a laterally compressed body and large pectoral fins, was a habitat specialist preferring slow flowing pools to swiftly flowing riffles, while V. barbatulus, that had a cylindrical body and small pectoral fins, was a habitat generalist with no special preference for either pools or riffles. C. lacustre and R. candidianus overlapped in mesohabitat use; both fish species preferred riffles to pools. The results of stepwise multiple regression analyses suggested that fish density was significantly related with stream width and water depth for V. barbatulus, but with current velocity, stream width, large boulder, canopy, and cobble for C. barbatus. For C. lacustre, further analyses based on stepwise multiple regression showed that fish density were significantly related with water depth, small boulder, and finer substrate but with water depth, stream width, large boulder, and cobble for R. candidianus; the separation in the microhabitat use might have alleviated the pressure for interspecific competitions despite of their overlapping in the mesohabitat scale. The results suggest that the diverse substratum composition may have accounted for the co-exsitence of these two benthic fishes, and ecomorphological characters, such as body form and fin size, may be useful predictors for habitat preferences of freshwater fishes in stream of Taiwan. The results would also provide valuable information for habitat management and ecological engineering of mountain creeks in Taiwan.