Abstract: The abundance, composition and distribution of zooplankton in relation to water quality parameters such as temperature, pH, dissolved oxygen, alkalinity, total dissolved salts total hardness and biochemical oxygen demand, were studied at monthly intervals from June 2011 to may2012 in Karanja river; Bidar at five locations selected. 36 species of zooplankton were identified as a total., which included 14species of rotifera 11 species of cladocera 8 species of copepoda and 3species of ostracoda...Dominant, rare and pollution indicators were studied. The affect of several physico-chemical parameters on the abundance and distribution of zooplankton is discussed. The investigation reveals that zooplankton better thrive in alkaline water and the water of Karanja river is fit for fish production and human use.
Keywords: Physico-chemical parameters, zooplankton bioindicators, seasonal fluctuation, Karanja River