author(s)
Kusumlata Goswami, Viveka Nand, RN Ram, Amita Saxena and RK Srivastava

abstract
The present investigation was carried out to determine the acute toxicity and behavioural responses of Amur carp (Cyprinus carpio haematopterus) fingerlings towards copper sulphate (CuSO₄). The fish were exposed in aquaria to different concentration of metal and the concentration of metal was increased gradually for 96 hours to investigate the response of the fish. Experimental fishes of average length of 7.92±0.46cm and weight of 8.20±0.28g were exposed to seven different concentrations of CuSO₄ with triplicates of each concentration. The median lethal concentration (LC₅₀) of copper to Amur carp for 96 h was found to be 1.811. With the increase of the concentration of metal the response of the fish mortality was also increased gradually. In addition, the behavioral changes of Amur carp at different metal concentrations were determined. Physiological responses like rapid opercular movement and frequent gulping of air was observed during the initial stages of exposure after which it became occasional. All these behavioral observations can be considered to monitor the quality of aquatic ecosystem and severity of pollution.