Inter-lake comparisons indicate that fish predation, rather than high temperature, is the major driver of summer decline in Daphnia and other changes among cladoceran zooplankton in subtropical Florida lakes

摘要: The mid-summer disappearance of Daphnia and the small size cladocerans in subtropical lakes have been explained as phenomena caused by high water temperature. Recent experimental observational studies suggest that instead, fish predation could be cause. In present study, we evaluated effects temperature comparing summer occurrence seasonality other where there was (a) vegetation a abundance diversity planktivorous fish; versus (b) no vegetation, turbid water, primarily benthivorous piscivorous fish. disappeared from plankton samples at all locations with yet it persisted year-round vegetation-free location despite identical temperatures (all were shallow isothermal). Body cladocerans, general, twofold lower vegetated locations, biomass threefold lower. Smaller species dominated especially summer. Our results demonstrate is able to tolerate temperatures, may more important regulator than for cladoceran size, taxonomic structure.