Wednesday, August 8, 2007 - 2:30 PM

OOS 34-4: Crossing the boundary: Coupling dynamics of ecosystems through complex life cycles

Sebastian J. Schreiber, College of William & Mary and Volker H.W. Rudolf, University of Virginia.

Organisms with complex life cycles often exhibit ontogenetic shifts in habitat use. Using models, we examine the spatial-temporal dynamics of consumer-resource interactions when consumers cross habitat boundaries as they mature. Our analysis reveals that the spatial patterns of habitat productivity and mortality risk play a crucial role in spatial-temporal patterns of abundance. For instance, if the juvenile habitat is sufficiently more productive than the adult habitat, then the community is dominated by adult consumers and juvenile resources. Alternatively, if the juvenile and adult habitat are comparably productive, then the community can exhibit alternative stable states with strongly skewed consumer age distributions and strongly skewed spatial distributions of resources. How these alternative states can lead to dramatic shifts in spatial-temporal dynamics as productivity or mortality risk is varied will be discussed.