Abstract
A hydroelectric project is proposed on the river Puyankutty in Idukki District of Kerala. In view of the proposed project an attempt was made to survey the fish species of the river during January 1998 to January 1999. The entire course of the river and its tributaries were covered and samples were collected using cast net and seine. Thirty-four species belonging to 11 families were colleced of which Puntius melanampyx, P. filamentosus, P. ticto, Garra mullya, Danio aequipinnatus, D. malabaricus, Barilius bakeri and B. gatensis were seen in abundance. Instances of epizootic ulcerative syndrome were seen in some individulas of Mastembelus armatus.