Second, population-level descriptions have not been translated into digestible summary statistics relevant to foraging theory. I address these limitations by presenting an approach for predicting movements of populations in which foraging behavior depends explicitly on internal state variables. I then derive ecologically relevant statistical assessments of forager performance, that quantify the suitability of specific behaviors to particular resource distributions. The performance statistics identify which spatial features of resource distributions are most important in determining habitat quality to foragers. University of Helsinki, FIN-00014 Finland.
Many species living in highly fragmented landscapes have high turnover rate of local populations.
The extinction rate is typically an increasing function of the size of the habitat patch, whereas the colonization rate is primarily a function of isolation. Based on these first-order effects of habitat patch size and isolation, a simple stochastic model can be constructed for the incidence of habitat patch occupancy. This model can be parameterized with data on patch occupancy and, if available, on turnover events. Because the model is spatially realistic, it can be used to study the formation of spatially correlated patterns in species distributions. Additional environmental factors can be included in the model, though experience suggests that often the effects of habitat patch area on extinction and isolation on colonization are so dominant that other factors make only a minor contribution.