Long-term impact of an invertebrate predator, Heterocope septentrionalis,on an arctic pond zooplankton community

摘要

1. A long-term field experiment to determine what forces structure and maintain the large-bodied zooplankton assemblages in ponds which lack visual predators was undertaken at the Toolik Lake Research Station in arctic Alaska. Predatory copepods, Heterocope septentrionalis, were introduced to a pond that lacked both fish and invertebrate predators, but contained small- to medium-sized zooplankton, Bosmina longirostris, Daphnia pulex, and Diaptomus pribilofensis. A second pond, which also lacked any predators but had a population of B. longirostris, but no other abundant species, served as a reference population for B. longirostris.