Avoiding hasty conclusions about effects of habitat fragmentation

Habitat fragmentation can potentially have negative impacts on many species because of both changes in habitat quality associated with edge effects (Saunders et al. 1991) and changes to population dynamics caused by the loss of connectivity (Hanski 1998). The practical implication is that it may be necessary to conserve a species in large continuous areas of habitat, rather than in several small areas (Burkey 1995), or to create corridors or stepping stones between fragments (Hobbs 1992). However, it is important that such management is based on evidence, rather than a priori assumptions about negative effects of fragmentation, and that the data are interpreted carefully. Otherwise, the conservation value of fragmented landscapes may be underestimated, or extensive resources may be invested in management that turns out to be ineffective or even deleterious.