Abstract for presentation at Biodiversity Extinction Crisis Conference - A Pacific Response

The “Field of Dreams” hypothesis suggests that “if you build it, they will come”, i.e., if a suitable habitat can be created, species will colonize it and function will be restored. We assessed this hypothesis by measuring aspects of the vegetation community, avian habitat use, and forest bird activity in two Acacia koa reforestation areas (KRAs) on Hawaii Island. Forest communities in the Hawaiian Islands have been transformed by human occupation, with declines and extinctions of forest bird populations the result. Acacia koa, an endemic co-dominant tree in wet montane Hawaiian forests, is the current focus of reforestation projects with both ecological restoration and economic goals. Vegetation survey results indicate that, in some cases, KRAs develop into forests that resemble native Hawaiian forests in structure and species richness, though not necessarily in species composition and evenness. Additional efforts may be necessary to ensure the development of a diverse understory. KRAs provide habitat for five or six of the eight native forest bird species common in nearby reference native forests. Percentages of individuals foraging, and indices of habitat relationships and foraging behavior were similar in restored and reference forests. Our results suggest that the establishment of A. koa stands may facilitate native ecosystem regeneration on degraded lands, and that these stands are a qualified restoration “success” with respect to habitat for native forest birds. We caution, however, that KRAs may not provide opportunities necessary for successful breeding efforts, and may therefore function as population sinks for some species.