Zooplanktons are heterotrophic planktonic animals floating in water. They serve as good indicators of changes in water quality. Studies on zooplankton of Cauvery river basin Nagore, Nagapattinam District, Tamilnadu. To assess the zooplankton population in pollution water from October 2015 to September 2016. The qualitative and quantitative evaluation of the variation in Cauvery river basin water showed high quantity of zooplankton population throughout the study period, the rotifer species formed dominated group over other groups of organisms. The present study revealed that the water of Cauvery river basin is highly polluted by direct contamination of sewage and other industrial effluents. Hence, the present study has been undertaken to examine the effect of pollutants and to assess the zooplankton population in Nagore Cauvery river basin at Station I and Station II Nagore Pattanachcheri village.
