Refuge data for projections of avian assemblage change at U.S. National Wildlife Refuges

The National Wildlife Refuge System (NWRS) provides one of the United States’ greatest protected area networks for wildlife conservation. As climate changes beyond historical ranges of variability, refuge managers are confronted with assessing the utility of refuges, including how to best manage refuges both individually and as a system to help species cope with rapid change. Using published species distribution models, we projected species-specific changes in environmental suitability for 590 native North American bird species under a 2°C future (~2050s under RCP8.5) at 525 refuges. We classified projected changes in suitability (i.e. improving, stable, or worsening suitability) and whether they crossed a model-derived persistence threshold at a refuge (i.e. potential colonization or potential extirpation). Overall, we found that a quarter of species (23% in summer, 26% in winter) could be different (i.e. turn over) across the refuge system despite protections. Seasonal communities are...