Fish Mortality in Bangalore Lakes, India

Large-scale episodal mortality among the freshwater fishes of certain lakes of Bangalore City, Karnataka State, India occurred in June 1995. We conducted an intensive study of the Sankey Lake which is situated in Sadashiva Nagar of Bangalore city where fish mortality occurred on quite a large scale during June - July 1995. These studies reveal that the fish-kill in Sankey Lake was due to a sudden and considerable fall in dissolved oxygen (DO) levels in some locations caused by sewage let into the lake resulting in asphyxiation. It was not due to any kind of infection because none of the fishes appeared to show any symptom of disease.