The ratio of native and alien fish species in Buyan and Tamblingan lakes, Bali

摘要

Buyan and Tamblingan lakes were often mentioned as twin lake because of its adjacent location. These two lakes were separated by approximately one-kilometer forest. Studies which recorded the fish species in those lakes were very limited so that a study was needed regarding that conditions as the initial step of management. This study aims to reveal and analyze the ratio of native and alien fish species which were found in Buyan and Tamblingan lakes, Bali. The fish sampling was held three times in different months at Buyan and Tamblingan lakes during 2017-2018, using a purposive sampling method. There were six locations sampling fish on each lake. It used experimental gill net with mesh size 0.5; 1.0; 1.5; 2.0; 2.5; 3.0; 3.5; 4.0 inches and trap. Three of the nine species that found in Buyan and Tamblingan lakes were native fish species. The ratio of native and non-indigenous fish caught in Buyan lake was bigger than from Tamblingan lake. Based on the length size of the most captured fish, the native fish of Osteochilus vittatus in Buyan lake was longer than Tamblingan, while the non-indigenous one, Poecillia reticulata had the same length size on the two lakes.