The National Amphibian Atlas is hosted and maintained by the Patuxent Wildlife Research Center of the USGS.
These maps were adapted from the "United States Amphibian Atlas Database" assembled at Ball State University by Laura Blackburn, M.S., Priya Nanjappa, M.S., and Michael J. Lannoo, Ph.D. (2002). Development of the original dataset was supported in part by grants or matching funds from the National Fish and Wildlife Foundation, United States Fish and Wildlife Service, and Disney Wildlife Conservation Fund, as background for the book Amphibian Declines: the Conservation Status of United States Species (Michael Lannoo, ed., 2005).
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