ABUNDANCE OF FOUR EXOTIC FISH SPECIES CYPRINUS CARPIO, CTENOPHARYNGODON IDELLA, HYPOPHTHALMICHTHYS MOLITRIX AND ARISTICHTHYS NOBILIS IN THE URPOD BEEL OF GOALPARA DISTRICT OF ASSAM

The present study was carried out to find out the abundance of four exotic fish namely, common carp, grass carp, silver carp and bighead carp in the Urpod beel of Goalpara district of Assam. The Urpod beel has a rich ichthyofaunal diversity and available almost all native fish species of Assam. During last few years the beel become habitat of some exotic fish species and their number has been increasing day by day, causes disturbances to the native fish species. The rate of exotic fish infestation in the beel was determined through field investigation and catch record from January 2011 to December 2011 in the fish landing centres of the beel. Abundance Index was calculated for the four exotic species from each catch data. A marked seasonal variation of the fish catch of native and exotic fishes was noticed. Among the four exotic species common carp recorded highest catch (4.99% of total catch) and bighead recorded lowest (2.84% of total catch).