Zooplankton are the grazers on the phytoplankton and a food base for the carnivorous as well as omnivorous fishes. The diversity of various type of zooplankton was studied of Mansagar Lake, Jaipur. The sample were collected and identified using standard keys of APHA (2005). The zooplankton communities in the Mansagar lake beloged to five major groups, such as Protozoa, Rotifera, Cladocera, Ostracoda and Copepoda. It was observed that some 5 genera of Protozoa, 10 genera of Rotifera, 5 genera of Cladocera, 5 genera of Copepodaand 3 genera of Ostracoda are available with monthly variation in the Mansagar lake.

Keywords: Zooplankton, Mansagar Lake, Water Quality.

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