Ecology, Environment and Conservation Paper

DIVERSITY OF SMALL INDIGENOUS SPECIES (SIS) OF FISH IN THE LOWER REACHES OF RIVER BRAHMAPUTRA, ASSAM

S. Basumatary, R.A. Baishya, B. Talukdar, H.K. Kalita, A. Dutta, U.C. Goswami, S.K. Srivastava and D. Sarma

Abstract

The present investigation deals with the diversity and abundance of Small Indigenous Species (SIS) of fish of the lower reaches of River Brahmaputra in Assam up to the border of Bangladesh. The study was conducted from December, 2012 to November, 2013 in the five prominent landing stations of the area. SIS was collected frequently in every month from the sampling stations. A total of 72 species belongd to 10 orders, 25 families and 52 genera were recorded during the study period. Out of the collected species, Cypriniformes were found most dominant order comprising 23 species followed by Siluriformes contributed 19 species followed by Perciformes and Clupeiformes consisting of 10 species each respectively. Out of the collected species, Mystus cavasius, Puntius sophore, Gudusia chapra, Amlypharyngodon mola, Ailia coila, Osteobrama cotio, Chanda nama, Parambassis ranga, Salmophasia bacaila, Setipinna phasa, Glossogobius giuris, Glossogobius gutum, Nandus nandus, Botia dario, Rita rita and Gagata cenia were most abundant Small Indigenous Species (SIS) of fish and the species like Botia rostrata, Botia lohachata, Clupisoma garua, Pachypterus atherinoides, Chaca chaca, Schistura corica, Rasborsa rasbora and Cirrhinus reba were observed least abundant SIS fish in the lower reaches of River Brahmaputra. Variations in the abundance of SIS category fish species were also observed in different seasons. It has been observed that the SIS of fish were found most abundant during winter season and least abundant during the Monsoon season.