Dynamics of metapopulations: habitat destruction and competitive coexistence

1. We take a previously studied model for two species one of which is competitively inferior coexisting in a patchy environment, and examine the effects of removing patches (that is, of decreasing the amount of available habitat). 2. Habitat destruction or patch removal reduces the number (and proportion) of patches occupied by the superior competitor, but can result in an increase in the total number of patches occupied by the inferior competitor (even though there are fewer patches in total). 3. It has long been appreciated that disturbance and destruction of habitat can create edge effects and other ecological changes favouring 'weedy' species. The present study suggests that patch removal can by itself favour such species, even in the absence of other, concomitant changes. 4. An implication relevant to conservation biology is that habitat loss can bring about changes in community composition in remaining patches, even if such patches themselves undergo no intrinsic changes whatsoever.