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.