In the desert southwest biodiversity is facing a changing landscape due to human population growth, expansion of energy development, and from the persistent effects of climate change among other threats. The 2012 Desert LCC science needs document recognized the importance of modeling and predicting habitat area, fragmentation and corridor network connectivity for a broad range of wildlife taxa. Tools and methods from conservation planning are available to address some of these issues, but tools to evaluate the expected benefits of corridors in mitigating climate change effects are only in their infancy. This USGS project will use quantitative spatial analysis and principles from landscape ecology to determine where habitat corridors could most effectively connect large landscapes to potentially ameliorate certain effects of climate and land use change on biodiversity. It will also compare existing data on corridors to determine where there is consensus among sources, and where there are gaps.