Am Nat. 2019 Apr;193(4):575-587. doi: 10.1086/702252. Epub 2019 Feb 27.
Exotic predators can have major negative impacts on prey. Importantly, prey vary considerably in their behavioral responses to exotic predators. Factors proposed to explain variation in prey response to exotic predators include the similarity of new predators to familiar, native predators, the prevalence and diversity of predators in a prey's past, and variation in a prey's innate ability to discriminate between predators and safety. While these factors have been put forth verbally in the literature, no theory exists that combines these hypotheses in a common conceptual framework using a unified behavioral model. Here, we formalize existing verbal arguments by modeling variation in prey responses to new predators in a state-dependent detection theory framework. We find that while some conventional wisdom is upheld, novel predictions emerge. As expected, prey respond poorly to exotic predators that do not closely resemble familiar predators. Furthermore, a history with more abundant or diverse native predators can lessen effects of some exotic predators on prey; however, under some conditions, the opposite prediction emerges. Also, prey that evolved in situations where they easily discriminate between safe and dangerous situations can be more susceptible to novel predators.
外来捕食者会对猎物产生重大的负面影响。重要的是，猎物对外来捕食者的行为反应差异很大。据推测，解释猎物对外来捕食者反应差异的因素包括新捕食者与熟悉的本地捕食者的相似性、猎物过去经历的捕食者的普遍性和多样性，以及猎物区分捕食者和安全的内在能力的变化。虽然这些因素在文献中被口头提出，但没有一个理论将这些假设结合在一个使用统一行为模型的共同概念框架中。在这里，我们通过在状态依赖检测理论框架中对新捕食者的猎物反应进行建模，使现有的口头论点正式化。我们发现，虽然一些传统观点得到了支持，但也出现了新的预测。如预期的那样，猎物对外来捕食者的反应很差，这些捕食者与熟悉的捕食者并不相似。此外，过去有更多或更多样化的本地捕食者的历史可以减轻一些外来捕食者对猎物的影响；然而，在某些情况下，会出现相反的预测。同样，在它们容易区分安全和危险情况的情况下进化的猎物可能更容易受到新捕食者的影响。
