Abstract:
Freshwater fish is a component of biodiversity in river, swamp, and lake ecosystems. Over exploitation of fish can change the characteristics of waters and result in the decrease in the abundance and diversity of fish. This study aimed to assess the species composition and diversity of fish community in three mainland water systems, i.e., river, swamp and reservoir. Purposive sampling of fish was done in three stations for each type of water. The data were analyzed descriptively and quantitatively, using the Shannon-Wiener index of diversity, evenness idex, Simpson index of dominance (C) and similarity
index of Sørensen (ISs) and Bray-Curtis (CBC). A total of 35 species belonging to 18 families were found in the three water types, where the river having the highest species richness (17 species), followed by the swamp (15) and the reservoir (11). The family Cyprinidae had the highest number of species. The index value of fish species diversity ranged from 1.20 to 2.55, considered as medium, the evennes index 0.5-0.9, considered medium to high, and the dominance index 0.09-0.39 considered as low. The Sørensen similarity index ranged from 0.12 to 0.29, and the Bray-Curtis similarity index 0.05-0.38,
considered as low. The river and swamp fish community had higher similarity index than the reservoir and the river, and the reservoir and the swamp. No common species was found in all the three water types. The water physico-chemical parameters met the quality standards to support fish life, namely pH 6.0-7.88, temperature 26.4-30.1oC, DO 6.2-8.1mg L-1, transparency 97-130 cm
