A large number of fish were found dead in Purale tank, which is located along National Highway 13, on the outskirts of the city on Sunday.
Haleshwar Naik and Umamaheshwar Naik, two farmers from Kalpanahalli village, had bagged the Department of Fisheries contract to rear fish in the tank. Gowri, Rahu, Katla and Gendla varieties of fish were being reared there.
Mr. Haleshwar Naik told The Hindu that more than one tonne of fish worth around ₹1 lakh have died. Following the fish kill, foul smell was emanating from the tank and the local gram panchayat deputed workers to remove the fish.
Scarcity of oxygen caused by depletion in the water level in the tank is suspected to be the reason for the fish kill. Mr. Haleshwar Naik said that because of the drought in the region, many farmers have illegally lifted water from the lake through pump sets.
He said that though a police complaint on this was lodged, no action was taken. He also alleged that a private educational institute located nearby was discharging sewage into the tank, thereby polluting it and causing the fish to die.
