SINGLE-SPECIES METAPOPULATION DYNAMICS - A STRUCTURED MODEL

We describe and analyse a general metapopulation model, which consists of a model of local dynamics within a habitat patch, and balance equations for dispersing individuals and the metapopulation. The model includes the effects of emigration and immigration on local dynamics. We derive the equilibrium population size distribution, which is skewed towards either small or large populations, depending on the relative magnitudes of local and metapopulation time scales. The model predicts a generally positive relationship between the fraction of occupied patches and the average local population size. Such a relationship has been commonly observed in nature. The model allows alternative stable equilibria, not found in models which ignore the effect of dispersal on local dynamics. We discuss the implications of our results for biological invasions and conservation biology. © 1992.