Spatial structure and dispersal dynamics in a house sparrow metapopulation

1. The effects of spatial structure on metapopulation dynamics depend upon the interaction between local population dynamics and dispersal, and how this relationship is affected by the geographical isolation and spatial heterogeneity in habitat characteristics.

2. Our aim is to examine how emigration and immigration of house sparrows, Passer domesticus, in a Norwegian archipelagic metapopulation are affected by key factors predicted by classic metapopulation models to affect dispersal: spatial and temporal variation in population size, inter-island distance, local demography and habitat characteristics.

3. This metapopulation can be divided into two major habitat types: (1) islands closer to the mainland where sparrows breed in colonies on farms, and (2) islands without farms, situated farther away from the mainland where sparrows are exposed to harsher environmental conditions.

4. Dispersal was spatially structured within the metapopulation; there was proportionally and numeri...