Zooplankton fauna and seasonal changes of Zarrineh river and its constructed dams; West Azarbaijan, Iran

This study was carried out to determine the diversity and density of zooplankton population of Zarrine river and its constructed dams to develop the aquaculture activities in the region regarding their key role on fish larvae feeding. The sample collection was conducted monthly during 2008 to 2009. In each site 30 liters of water were filtered with a 55 μ mesh size plankton net and one liter of obtained extract was fixed with 4% formalin and its zooplankton fauna counted and identified.. The results showed that zooplankton fauna from different parts of Zarrine river included 3 major groups: Rotatoria, Cladocera and Copepoda. These groups comprised of 24 genera and 40 species. According to the species number, among the studied groups Rotatoria, Cladocera and Copepoda had the higher number of species, with 12 genera and 24 species, 7 genera and 10 species, 5 genera and 6 species , respectively. Seasonal studies showed that spring, autumn, winter and summer included 52%, 20 %, 16 %, and 12 % of zooplankton population, respectively.