Literature review dataset on predation-risk effects

A well-accepted narrative in ecology is that prey modify traits to reduce predation risk, and the trait modification has costs large enough to cause ensuing demographic, trophic and ecosystem consequences, with implications for conservation, management, and agriculture. But ecology has a long history of emphasizing that quantifying the importance of an ecological process ultimately requires evidence linking a process to unmanipulated field patterns. We suspected that such process-linked-to pattern (PLP) studies were poorly represented in the predation risk literature, which conflicts with the confidence often given to the importance of risk effects. We reviewed 29 years of the ecological literature which revealed that there are well over 4000 articles on risk effects. Of those, 349 studies examined risk effects on prey fitness measures or abundance (i.e., non-consumptive effects) of which only 26 were PLP studies, while 275 studies examined effects on other interacting species (i.e., trait mediated indirect effects) of which only 35 were PLP studies. PLP studies were narrowly focused taxonomically and included only 3 that examined risk effects on unmanipulated patterns of prey abundance. Before asserting that risk effects drive ecological community dynamics, more attention must be given to examining whether risk-effect processes influence unmanipulated field patterns across diverse ecosystems.