Interaction between hunting strategy, habitat type and stratum drive intraguild predation and cannibalism

Intraguild predation (IGP) is a common interaction between generalist predators when they competitively exploit similar resources and prey on each other. Theoretical models predict limitations for intraguild predator coexistence unless some mechanisms, such as utilization of alternative prey (i.e., trophic niche partitioning) and cannibalism, increase the relative intraspecific clustering and interspecific segregation. As hunting strategies determine trophic niches of predators and their own vulnerability to predation, the hunting strategies may also determine the relative importance of cannibalism, predation, and exploitative competition and consequently the intensity of IGP. The importance of hunting strategies on the potential outcome of IGP and how habitat properties modify the interaction between hunting strategies remain poorly understood. Using published data on spider prey of spider predators, we first investigated how predation of a top-predator on a mesopredator is determined ...集团内捕食（intraguild predation，IGP）是广食性捕食者间的常见互作形式：当这类捕食者竞争利用相似资源并相互捕食时，即会发生此类互作。理论模型预测，集团内捕食者的共存存在限制，除非诸如利用替代猎物（即营养生态位分化）与同类相食这类机制，能够提升相对的种内聚集度与种间分离程度。由于捕食策略不仅决定捕食者的营养生态位，还决定其自身被捕食的易感性，因此捕食策略也可决定同类相食、捕食行为与资源利用型竞争的相对重要性，进而影响集团内捕食的强度。目前，学界对于捕食策略如何影响集团内捕食的潜在结局，以及生境属性如何调控捕食策略间的相互作用，仍缺乏深入认知。本研究利用已发表的蜘蛛捕食者的蜘蛛猎物相关数据，首先探究了顶级捕食者对中型捕食者的捕食作用是由哪些因素决定的……