Mortenson Lake National Wildlife Refuge is a 1,776-acre protected area in southern Wyoming managed by the U.S. Fish and Wildlife Service. At 7,256 feet above sea level, it contains several small alpine lakes, including Mortenson Lake, and provides habitat for migratory birds. The refuge was established in 1993 after a small wild population of the Wyoming toad was rediscovered nearby in 1987. The species had been listed as endangered in 1984 and was widely believed extinct in the wild. Since 1995, captive-bred offspring have been released there to help stabilize the population, and the area remains closed to public access to support that recovery effort.