Species Diversity and Abundance in Insular Systems

University Of California-Davis, Davis CA

Investigators

Abstract

"Species Diversity and Abundance in Insular Systems" DEB 9981912 T.W. Schoener and D.A. Spiller, PIs This research continues a study of food webs, relations that specify which species eat which in an ecological community. We simulate invasion of a large predator onto islands having a variety of small predators as well as herbivores and plants. Such predators may not only exert profound direct effects by consumption, but via intervening species, can indirectly affect other components, including plants. Such indirect effects may be positive or negative: e.g., the large predator may consume insects that eat plants (positive), or consume small predators that eat the plant-eating insects (negative). In addition to changes in numbers, changes in behavior and morphology of affected species are studied. The experiment is performed within a system of islands, many of which have been monitored for natural invasions and extinctions for nearly two decades. Planned monitoring includes extensive documentation of damage and recovery from the recent Hurricane Floyd, a devastating, Category 4 storm. Results of this project should significantly enhance our understanding of how large natural disturbances affect the dynamics of ecological systems.