Fish death in lakes

摘要

An incidence of mass-scale fish mortality in Bangalore, India was reported recently in the local newspaper as front-page headline: 'Five tonnes of fish die in Ulsoor Lake. From being a clear, tranquil water body, the recently restored Ulsoor Lake has become a sea of dead fish'. Among the views expressed as the cause of this tragedy were: (1) Chemicals flushed into the lake, following a cleaning of the BCC-owned Ulsoor swimming pool; (2) lowered Biological Oxygen Demand; (BOD) level due to the approaching summer [BOD], expressed as mg O sub(2) per l, is the amount of dissolved oxygen needed to oxidize organic materials to carbon dioxide and water at a particular temperature and pressure. If there is a large quantity of organic waste, there will be a lot of bacteria working to decompose this waste. The purpose of this correspondence is to (1) inform that incidences of fish death are not unique to water bodies in Bangalore; (2) review the available microbiological and biochemical explanations of fish death observed elsewhere, and (3) apprise of a biological control of fish death proposed in the literature.