OMAHA, Neb. (AP) — A breeding program in Omaha is trying to keep a toad native to Wyoming from extinction.

The Wyoming toad is considered critically endangered and one of the four most endangered amphibian species in the United States. The toad is listed as extinct in the wild on the International Union for Conservation of Nature's Red List of Threatened Animals because it can only be found in only one protected place, a pond in the Mortenson Lake National Wildlife Refuge near Laramie, Wyo.

The Omaha World-Herald reports that Omaha's Henry Doorly Zoo & Aquarium is one of eight U.S. zoos that are breeding the toads for release in Wyoming. The zoo has sent nearly 2,800 tadpoles and young toads to Wyoming since the program started in 1995.