REU: Causes of Selective Predation and Costs of Predator- Avoidance by Stream Insects

点击翻译按钮获取中文摘要

The objectives of this research are to resolve the mechanistic and evolutionary causation of selective predation by stream dwelling stoneflies and measure the lethal and sublethal costs of disturbance by mayflies, feeding rates, growth rates and fecundity. Videotaped behavioral observations, and predation trials will test for frequency-dependent prey selection, induction of feeding preference, responses of predators and prey to hydrodynamic clues, and the "threat sensitivity hypothesis", which states that predator-avoidance behavior esculates with risk of predation. Replicated circular stream channel experiments will test for microhabitat overlap of predators and prey, enable comparison of growth rates and fecundities of stoneflies. Choice chamber experiments will test effects of predators on mayfly use of periphyton resource patches. Functional response and benthic data will be used to determine the potential impact of lethal and sublethal effects of stonefly predation on prey population dynamics. The key contributions of the research will be tests of new hypotheses on behavioral mechanisms underlying patterns of selective predation and predator-avoidance and the first known experimental study of why natural selection might have favored certain predator and prey behaviors.