The practice of conserving North American biodiversity in a changing climate

Background/Question/Methods



Motivated by declines in biodiversity exacerbated by climate change, we identified a network of conservation sites designed to provide essential habitat for species while supporting dynamic shifts in ranges and ecosystem composition. Our 12-year study involved 287 scientists in 14 study regions across the conterminous U.S. (CONUS). To ensure the network represented all species and ecosystems, we stratified CONUS into 68 ecoregions and within each we comprehensively mapped the geophysical settings that corresponded to current ecosystem and species distributions. For each geophysical setting, we identified the portion with the highest connected topoclimatic diversity as an estimate of site resilience. Next, we identified areas of high importance for connectivity within and across ecoregions based on an analysis of inferred climate gradients and resistance to human modification. Finally, we identified places that had been independently recognized for their biodiversity value based on ecoregional or state-based assessments. Areas that met two or more of these criteria collectively delimit a connected network of lands covering 35% of CONUS.



Results/Conclusions



The network includes 38% (5%-82%) of every ecoregion, multiple examples of all geophysical environments selected for their site resilience, over 250,000 locations of rare species or exemplary natural communities, and it is configured to anticipate and facilitate species movement along climatic gradients. Currently the network is 44% secured. If fully conserved, the network could provide connected resilient habitat for current and future biodiversity to adapt to changing climatic conditions, deliver climate mitigation co-benefits, and form the spatial foundation for targeted conservation strategies to sustain biodiversity.