Population and community consequences of spatial subsidies derived from central place foraging... Or troglobites, guanophiles, and inquilines, oh my!

Central place foragers, such as ants, beavers, and colonial seabirds, can act as biological conduits, subsidizing local communities with allochthonous resources. Such biologically vectored resource redistribution lends itself well to consideration as a problem in spatial ecology.  Drawing on an example from cave ecology, we develop a model based on the dispersal kernel framework.  We explore how the size of the patch in which central place foraging occurs, and the spatial distribution of foragers within that patch, feed back to influence the population dynamics of the central place forager and the species richness of the associated recipient community.  We demonstrate that the particular way in which the central place forager uses space can have two important effects.  First, space use determines the stability of forager population and establishes patch-size thresholds for persistence, stable equilibria, and limit cycles. Second, alternative dispersal kernels lead to qualitatively different scaling relationships between the size of the foraging patch and species richness back at the central place.  These analyses provide a new link among elements of ecology related to animal behavior, population dynamics, and species diversity while also providing a novel perspective on the utility of integrodifference equations for problems in spatial ecology.