Dispersal and connectivity in populations of the common lizard Lacerta vivipara: an experimental approach

摘要

Theoretical and empirical studies of the consequences of habitat fragmentation and isolation suggest that dispersal behaviour improves the persistence of local populations and that characteristics of dispersal influence the spatial structure and dynamics of metapopulations. A better understanding of the costs and benefits of dispersal could allow one to predict how populations would respond when confronted with perturbations. In this paper, the effects of preventing dispersal on the short term behaviour of the common lizard (Lacerta vivipara) are studied experimentally. Situations where two experimental populations are connected were compared to situations where two experimental populations were not connected. Preventing dispersal had a destabilizing effect since it provoked dispersal behaviour in individuals which would not otherwise have dispersed. The effects on population persistence of breaking a connection between populations could therefore be more important than predicted by demographic models which do not include interactions between individual behaviour and habitat fragmentation.