The many faces of fear: comparing the pathways and impacts of nonconsumptive predator effects on prey populations.

ABSTRACT:

Background

Most ecological models assume that predator and prey populations interact solely through consumption: predators reduce prey densities by killing and consuming individual prey. However, predators can also reduce prey densities by forcing prey to adopt costly defensive strategies.

Methodology/principal findings

We build on a simple Lotka-Volterra predator-prey model to provide a heuristic tool for distinguishing between the demographic effects of consumption (consumptive effects) and of anti-predator defenses (nonconsumptive effects), and for distinguishing among the multiple mechanisms by which anti-predator defenses might reduce prey population growth rates. We illustrate these alternative pathways for nonconsumptive effects with selected empirical examples, and u

SUBMITTER: Preisser EL 

PROVIDER: S-EPMC2409076 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature