Spatial Autocorrelation, Dispersal, and the Maintenance of Source-Sink Populations

Populations may be regulated by both local density-dependent factors and spatial variation in habitat quality. I explore the influence of spatial autocorrelation in habitat quality on the survival of model populations. Dispersal is modeled as Markov transitions between patches. A finite rate of population increase was assigned to each patch. Total habitat area and mean dispersal distance had strong effects on overall population persistence. The effect of spatial autocorrelation was relatively weak, but interacted with dispersal distance. The results suggest that landscape pattern can play an important role in population survival, but its importance depends crucially on dispersal behavior.