Local Dispersal and Coexistence in a Metacommunity Model with Trophic Structure

Abstract

One of the major goals of ecology is to understand the mechanisms which promote species coexistence. Much progress has been made in recent years in understanding how spatial processes influence diversity. Here we present a pair of models designed to investigate the role of one spatial process, localized dispersal, in promoting regional species coexistence when trophic structure is present. The model community considered is a two-predator, two-prey assemblage with cyclic endstates. Through analysis and simulation, we show that increasing the range of species dispersal can inhibit regional species coexistence. This result is at odds with the conclusions of some previous studies which considered locality within a single trophic level, and suggests that the relationship between dispersal distance and regional coexistence may be more complicated than previously realized.