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 A. 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. KRAs provide foraging
habitat for six native forest bird species. Percentage of individuals foraging,
and indices of habitat relationships, foraging opportunity, and foraging effort
were similar in the restored and reference forests. Time allocation among broad
behavioral categories was also similar for the species found in both habitats.
If the goal of A. koa
reforestation efforts in Hawaii is to provide foraging habitat for native
forest birds, KRAs can be considered at least a partial restoration "success".
However, KRAs may not provide opportunities necessary for successful breeding
efforts, and may therefore function as population sinks for some species. We
also caution that KRAs may be unsuitable habitats if their successful use by
the birds will require behavioral plasticity as our results suggest these species'
activities do not differ among habitats.