Understanding Zooplankton Communities in Farm Dams: the Importance of Predation

Abstract

The species composition, species abundance and size distribution of the zooplankton community of farm dams in the Adelaide Hills were largely controlled by predation. In 3 farm dams without fish, winter-spring zooplankton communities were dominated by the large cladoceran Daphnia carinata and a species of the large calanoid Boeckella along with smaller populations of Calamoecia, Ceriodaphnia, Mesocyclops leuckarti and Asplanchna brightwelli . The mean length of zooplankters in each of the dams was 0 multiplied by 95, 1 multiplied by 28 and 1 multiplied by 33 mm, and the largest zooplankters were 3 multiplied by 6 mm. In summer, large populations of the notonectid Anisops deanei decimated the zooplankton and virtually eliminated D. carinata .