Habitat Loss, Fragmentation, and Restoration

ABSTRACT

 

Abstract

The loss and fragmentation of habitat is a major threat to the continued survival of many species. We argue that, by including spatial processes in restoration management plans, the effects of habitat loss and fragmentation can be offset. Yet few management plans take into account spatial effects of habitat conservation/restoration despite the importance of spatial dynamics in species conservation and recovery plans. Tilman et al. (1997) found a "restoration lag" in simulations of species restoration when randomly selecting habitat for restoration. Other studies have suggested that the placement of restored habitat can overcome effects of habitat loss and fragmentation. Here we report the findings of simulations that examine different regional management strategies, focusing on habitat selection. We find that nonrandom restoration practices such as restoring only habitat that is adjacent to those occupied by the target species can dramatically reduce or negate any restoration lag. In fact, we find that the increase in patch occupancy of the landscape can be greater than two-fold in the adjacent versus the random scenarios after only two restoration events, and this increase can be as great as six-fold during the early restoration phase. Many restoration efforts have limitations on both funds and available sites for restoration, necessitating high potential success on any restoration efforts. The incorporation of spatial analyses in restoration management may drastically improve a species' chance of recovery. Therefore, general principles that incorporate spatial processes and sensible management are needed to guide specific restoration efforts.