Zooplankton samples were collected seasonally from three stations in the south of
Al-Hammar Marshes southern Iraq during the period from January to December 2011, by
Plankton net of a mouth aperture of 40 cm and a mesh-size 0.90 mm mounted with a f
low
meter in the mouth. The results showed that the population density of Cladocera ranged
between 79 ind/m3 during winter at station 1 (Al-Mas-hab) and 41971 ind/m3 during spring
at station 2 (Hareer). Density of Cladocera was positively correlated with water
temperature and to a lesser extent with salinity. About 13 species of Cladocera belonging
to 11 genera were recorded at three stations. The high values of diversity were recorded in
winter at all stations (1.68, 1.16, and 1.68 respectively) while the lowest values were
recorded during spring at all stations (0.06, 0.03, and 0.01 respectively).
