Ichthyofaunal Diversity of Babai River of Dang Distict, Nepal

Abstract

Babai River is one of the important River, originated from the eastern end of Dang valley. The present study deals with the study of fish diversity, habitat of fish species and environmental variables for three times in eight months covering three seasons; autumn, winter and spring. Fish sampling was done by using cast net, mosquito net and hook and line with the help of local fisherman from four sampling stations within 7km. Altogether 24 species of fishes belonging to 5 orders, 9 families and 15 genera has been recorded. Cypriniformes was found most dominant with 18 fish species followed by Siluriformes which comprises 3 fish species. The most dominant species of this river was found Puntius sophore followed by Barilius bendelensis, Puntius terio and Puntius ticto. The highest and lowest frequency occurrences were recorded 17.40 and 0.096 of Puntius sophore and Erethistes pussilus respectively. The highest Shannon Wiener diversity index, Evenness index was found in station III and highest Margalef value was found in station II whereas the lowest value of Shannon Wiener diversity and Margalef Species richness value was observed at station I and lowest value of Evenness index was observed at station II. Similarly, the highest Shannon Wiener diversity index , Margalef Species richness, Evenness index was found in Winter whereas lowest value of Shannon Wiener diversity index , Margalef Species richness, Evenness index was found in spring. The RDA analysis showed that environmental variables like water temperature, pH, free carbon-dioxide, water velocity and dissolved oxygen plays vital role to shape the fish assemblage structure of Babai River.