COS 91-8 - Promoting stabilizing asynchrony in homogenous metacommunities

Friday, August 12, 2016: 10:10 AM
315, Ft Lauderdale Convention Center
Sean M. Hayes, Department of Biology, University of California Riverside, Riverside, CA and Kurt E. Anderson, Department of Biology, University of California, Riverside, Riverside, CA

A major effect of advancing human development has been changes to the patterns of dispersal between communities. Dispersal has been increasingly revealed as a major force enabling the persistence of species and functioning of communities. However studies have emphasized the effects of dispersal rate rather than structure, a complex and multidimensional property. To address this we investigate the role of dispersal structure on unstable predator-prey interactions in spatial Rosenzweig-MacArthur models. Dispersal has been proven capable of stabilizing otherwise unsustainable interactions through both rescue and spatial averaging effects, but only when patches can be prevented from synchronizing. To address this we test the tendency of different dispersal patterns to synchronize metacommunities composed of identical predator-prey communities connected by dispersal. The rate of dispersal is held constant throughout community patches and treatments. As a result community patches are truly identical to one another, and intuitively synchronization would be inevitable. 


Nevertheless, we demonstrate that synchronization can be prevented and stabilization of an unsustainable predator-prey interaction achieved even when all patches are identical through manipulation of the structure of dispersal connections between community patches. Moreover, we illustrate substantial and striking differences in the ultimate stability of asynchronous metacommunities produced by differences in dispersal structure. As the rate of dispersal is constant among all communities for all treatments, this further demonstrates the importance of structure alone. Using network analysis and other techniques from applied mathematics, we highlight the structural characteristics driving these differences. We also note differences in response to perturbation produced by altering spatial structure, an important aspect of their altered stability. Finally, we discuss the application of these results and methods to the management of spatial communities threatened by human development.