THE IMPACT OF HABITAT SELECTION ON THE SPATIAL HETEROGENEITY OF RESOURCES IN VARYING ENVIRONMENTS

This article used a series of simple models to examine the population dynamics of two independently reproducing resource populations in spatially distinct patches, when the resources are eaten by a fixed consumer population that moves adaptively between the patches. The models assumed that each resource (patch) experienced a potentially different set of environmental influences on its growth rate. The models also assumed that consumer distribution shifted more rapidly toward the more rewarding patch as the difference in resource intake rates between the patches increased. In most cases, the time‐average of spatial heterogeneity of resource densities is greatest for intermediate rates of consumer movement. The average resource densities and consumer fitness are also frequently maximal when movement rates are intermediate. Intermediate movement rates allow enough of a lag in consumer redistribution that resources periodically escape overexploitation. Resource densities and heterogeneity may increase by a large factor as the rate of consumer movement (or the sensitivity of consumer movement to differences in intake rates) increases. These findings were used to discuss the potential effects of predators that interfere with habitat selection by their prey. Such predators may have positive or negative effects on the density of their prey and of their prey's resources. Predators may also either increase or decrease the spatial heterogeneity of resource densities.