Consequences of Adaptive Individual Behavior, Higher Order Interactions, and Food Web Structure in a Larval Anuran Community

食物网结构调节动物种群大小的方式目前受到许多理论和经验的关注。这一建议旨在发展对由鱼类、无脊椎捕食者和两种无脊椎动物幼虫组成的食物网中相互作用强度的机械理解。通过这种食物网介导的间接影响是两种无尾蚁在从永久池塘到临时池塘的环境梯度中相对成功变化的核心。从个体行为到大规模的食物网操作，从机制到对社区现象的理解，食物网的相互作用在几个层面上进行了探讨。该提案的一个重点是实验评估由猎物对捕食者的存在的行为反应产生的高阶相互作用的重要性。这些高阶相互作用改变了猎物之间竞争相互作用的性质，而捕食者对猎物没有任何直接的死亡率影响。由于猎物对捕食者的行为反应的广泛发生，这种高阶相互作用在许多生态系统中可能很重要。无尾动物的行为反应反过来又受到生长（竞争能力）风险权衡的调节，一个通过活动水平，另一个通过栖息地选择。个人行为层面的理论将被开发、测试并用于为理解适应性个人行为的社区后果提供理论基础。这两种权衡都与许多分类群中的相互作用有关。最后，由于行为反应通常是个体大小的功能，因此本研究将探讨行为表达的个体发育限制以及物种相互作用的后果。

The manner in which food web structure regulates the size of animal populations is currently receiving much theoretical and empirical attention.. This proposal seeks to develop a mechanistic understanding of the strength of interactions in a food web consisting of fish, invertebrate predators, and two anuran larvae. Indirect effects mediated through this food web are central to changes in relative success of the two anurans along the environmental gradient from permanent to temporary ponds. The food web interactions are approached at several levels ranging from individual behavior to large scale food web manipulations to build from mechanisms to an understanding of community phenomena. A focus of the proposal is an experimental evaluation of the importance of higher order interactions generated by behavioral responses of prey to the presence of their predators. These higher order interactions alter the nature of competitive interactions among prey in the absence of any direct mortality effects of predators on prey. Because of the widespread occurrence of behavioral responses of prey to predators, such higher order interactions are likely important in many ecological systems. The behavioral responses of the anurans in turn are mediated by growth (competitive ability)-risk tradeoffs, one through activity levels and the other through habitat choice. Theory at the individual behavioral level will be developed, tested and used to provide a theoretical basis for understanding the community consequences of adaptive individual behavior. Both of these tradeoffs are relevant to interactions in many taxa. Finally, because behavioral responses are often functions of individual size, the work will explore ontogenetic constraints on behavioral expression and the consequences to species interactions.