摘要

A long-standing debate within conservation is how best to allocate limited management resources: should reserve area be increased, should anthropogenic disturbances be mitigated, or should connectivity be increased? We explore these issues for the San Diego cactus wren, a California Species of Special Concern. To assess the relative benefit of different post-fire habitat restoration strategies, we forecasted wren abundance over the next 100 years under three restoration strategies: (i) create new "stepping stone" habitat patches to form corridors which connect existing patches, (ii) augment existing habitat patches, and (iii) create new habitat patches in areas with low fire risk. We considered both small-scale and large-scale restoration efforts of 20 and 200 ha of habitat, respectively. To forecast wren abundance, we used a meta-population model created from maps of wren abundance, cactus abundance, land use, and estimated fire probability. Estimates of fire probability were obtained by relating previous fire locations to environmental variables and human population density. Results indicate that the best management strategy for a 20-ha restoration effort is to augment habitat in patches habitable for wrens, and that the best strategy for 180 ha of additional restoration (or 200 total hectares) is to improve wren dispersal via new corridors. Results also indicate that there is no decline in long-term wren abundance caused by planning the first 20 ha of restoration separately from planning a subsequent 180 ha. Our modeling approach provides insight into the relative benefit of several realistic restoration scenarios, providing an important tool for species conservation and habitat restoration on complex landscapes.

  • 出版日期2014-7