Planning for current species distributions is more effective than planning for nature’s stage in the face of climate change

Abstract

Climate change poses a significant threat to biodiversity. Increasing the number and size of protected areas is one of the most frequently cited approaches to addressing this threat. However, because climate change is already shifting species distributions, traditional reserve-selection strategies that rely on current patterns of biodiversity may be ineffective. One commonly suggested alternative is to protect geophysical diversity, or the various edaphic, topographic, elevational, and geographical features of a landscape. As climate change continues to drive changes in species distributions, geophysically diverse landscapes may have the potential to provide the habitat heterogeneity needed to accommodate new ranges of species. We use projected climate-driven shifts in species distributions to compare the effectiveness of reserve networks designed to increase the representation of today’s species distributions to the effectiveness of reserve networks built to increase the protection of geophysical diversity. Reserve networks built with biological targets protected up to 18% more species than reserve networks built with geophysical targets and geophysical networks protected few more species than did randomly selected networks. These patterns were consistent across future climate scenarios with varying levels of change. Our results indicate that prioritizing areas for protection based on current patterns of biodiversity is likely to be more effective at protecting future patterns of biodiversity than prioritizing areas based on geophysical diversity.