生物多様性と絶滅危惧種のジャーナル

The Current Status of Small Indigenous Fish Species (SIS) of River Gorai, a Distributary of the River Ganges, Bangladesh

Abstract

Hanif MA, Siddik MAB, Nahar A, Chaklader MR, Rumpa RJ, Alam MJ and Mahmud S

Small indigenous fish species (SIS) play a vital role in providing animal protein sources for human. The Gorai river, a Ganges tributary is a habitat of considerable number of SIS. A total of 11040 individual from 40 species were collected belonging 7 orders and 19 families using 5 fishing nets and 1 fish trap of which 2 species were critically endangered, 7 endangered, 7 species vulnerable, 18 species not threatened, 2 data deficient and 4 species were not in evaluated category. Dominant orders were Cypriniformes and Perciformes each contained 12 species, dominant family was Cyprinidae (11 species) and most dominant species was Chela cachius (2253 individuals). Diversity indices ranges from Simpson’s dominance index (0.06-0.09), Simpson’s index (0.91-0.94), Shannon Weiner index (3.08-3.24), Evenness (0.56-0.66), Menhinick’s index (0.61-0.67), Margalef’s index (4.48-4.77), Equitability (0.84-0.89) and Fisher alpha (5.86-6.31), respectively. Highest numbers (38) of SIS were caught by set bag net. Maximum total length 4.6 cm of Corica soborna was the new record. Considering the nutritional importance and reducing number of SIS inhabiting in the river Gorai, the present study aimed at documentation of SIS, their threatened status and conservation of SIS through laws and regulations.