The Hawaiian crow is the most endangered corvid species in the world and the only species left in Hawaii. Like other critically endangered species, harming the Hawaiian crow is illegal under U.S. federal law. By 1994, the populations dwindled to 31 individuals; 8 to 12 were wild and 19 held in captivity.
The Wyoming toad or Baxter's toad (Anaxyrus baxteri, formerly Bufo baxteri) is an extremely rare amphibian that exists only in captivity and within Mortenson Lake National Wildlife Refuge in Wyoming in the United States. The Wyoming toad was listed as an endangered species in 1984, and listed as extinct in the wild since 1991.