Risk assessment for Iberian birds under global change

Conservation priority areas and programs are often established without consideration of future changes in species distributions. However, global change is expected to threaten the persistence of several species while offering opportunities for range expansion to others. In this study, building on previous work, we develop and implement an approach to classify bird species according to their degree of exposure and vulnerability to future climate and land-use change, including climatically driven changes in vegetation. To examine species exposure to environmental changes, we first fitted environmental envelope models and projected then into the future under scenarios of climate, land use and vegetation change. Then, we estimated species vulnerability by taking into account traits that are expected to render species vulnerable to environmental change while considering, simultaneously, the current IUCN conservation status of species. Our results show that bird species highly (and negatively) exposed to future environmental changes are currently less threatened and possess characteristics that render them less susceptible to local extinction than species that are less exposed. Our results reinforce the need to complement studies of global change impacts on biodiversity, typically based on assessments of species exposure to changes, with additional information related to the ability of species to persist under such changes. Nevertheless, we stress that while combining different sources of information is important, it is the comparison of outcomes from these different sources of information that enables development of alternative management strategies. Depending on the source of risk (e.g., exposure to global change versus vulnerability traits to multiple stressors) alternative conservation actions might be required.