Zooplankton of Tahar stream (Tunceli)

In from study, zooplankton fauna of Tahar Stream were investigated. Samples were taken monthly from 3 different stations between June 2013 and May 2014. Water temperature, pH and dissolved oxygen of water were determined in situ. Zooplankton samples were taken by means of 55 µ mesh-sized standart plankton net and were preserved in 4% formaldehyde solution. A total of, 35 zooplankton species were recorded. 28 rotifera species belonging to 15 families, 5 Cladocera species belonging to 4 families, and 2 Copepode species belonging to 1 family were determined. According to Shannon Wiener species richness index analysis, species richness was found highest in may (H′=2.43). The least index value was found in september (H′=1). As the result of Sorenson Similaritiy Index values Sation I and II's similarity was found highest with (65%) and lowest value was recorded between stations II and III with (52%). The dominant zooplankton species, Keratella quadrata was reached to its maximum relative density with 36.3% in may. Among all zooplankton Rotifera was represented with 86.5%, Cladocera 10% and Copepoda 3.5% percentage. Key Words: Rotifera, Copepoda, Cladocera, Tahar Stream