From http://gapanalysis.usgs.gov/species/: "GAP's Species data includes vertebrate range maps and distribution models for amphibians, birds, mammals, and reptiles occurring in the U.S. These kinds of maps and data are fundamental to conservation planning, forecasting (e.g., climate change), and research."
Download data (http://gapanalysis.usgs.gov/species/data/download/), view data in the GAP Species Viewer (http://gapanalysis.usgs.gov/species/viewer/) or access web services (http://gapanalysis.usgs.gov/species/data/web-map-services/)
