The experimental fragmentation of landscapes of a natural ecosystem resulted in declines in the abundance and distribution of most species in the multispecies animal community inhabiting the landscapes and the extinction of many species. These declines caused the deterioration of the positive interspecific relation between local population abundance and distributional extent in this community. However, when patches were connected by habitat corridors, an immigration "rescue effect" arrested declines in both abundance and distribution and maintained the observed positive relation between them. These results demonstrate the importance of metapopulation dynamics and landscape connectivity for the persistence of populations in fragmented landscapes.