The ocelot and the bighorn sheep are both listed as endangered species by the U.S. Fish & Wildlife Service. Each of the other three pairs of animals includes at least one threatened (not endangered) species.
The American Alligator continues to be listed as a threatened species due to its similarity in appearance to the American Crocodile, which is an endangered species.
The bald eagle, which was once on the brink of extinction, has now recovered enough so that it has been removed from the list of endangered species. The red-cockaded woodpecker has remained on the endangered list for three decades.
The American black bear and the grizzly bear are both designated as threatened species.
