Climate change vulnerability of terrestrial vertebrates in a major refuge and dispersal corridor in North America

Abstract

Aim: The Appalachian forests ecoregion in eastern North America supports a diverse and highly endemic temperate biota, which is potentially threatened by rapid climate change. We investigated possible outlooks for biodiversity in this biologically important ecoregion under future climate change. Location: Appalachian forests ecoregion, USA. Methods: We estimated distributional shifts for 258 forest-dependent vertebrates of conservation concern in four major taxonomic groups (amphibians, birds, mammals and reptiles) under short- (2040) and long-term (2080s) climate change using ecological niche modelling. We examined which groups are likely most vulnerable to climate change and identified places predicted to experience the greatest changes in their species assemblages and those predicted to support high species richness under various future scenarios. To assess species' vulnerability, we compared and regressed future projected range against present range estimates for each species. To evaluate which places could see greatest changes, we mapped species richness and turnover in each taxonomic group. Results: A total of 30%–33% and 31%–38% of species were predicted to lose > 50% of area that is currently climatically suitable under short- and long-term climate change, respectively. We expect climate change to impact amphibians and mammals more than birds and reptiles: a much larger fraction of amphibian and mammal (22%–48% in 2040; 29%–56% in 2080s) species were predicted to lose more than half of their present climatically suitable habitat area compared with birds and reptiles (1%–12% in 2040; 6%–12% in 2080s). While species were predicted to move northward and upslope assuming full dispersal, the Blue Ridge, Cumberland Plateau and southern Central Appalachians subregions are poised to remain as richness hotspots under the broad range of scenarios explored in this study. Main conclusions: Our results highlighted species groups and locations that policymakers and conservation practitioners should emphasize in planning vertebrate conservation efforts in the Appalachians under future climate scenarios.