There are many organizations in the United States and all over the world that study and research plant and animal species, determining which ones may be headed for extinction (when a species of plant or animal dies out completely). Any species in such danger is described as “endangered.” Once a species is endangered, it becomes illegal to hunt that animal or destroy its habitat.
In 2008 the U.S. Fish and Wildlife Service, the organization that maintains the nation’s list of endangered and threatened plants and animals, listed more than 1,000 animals worldwide (“threatened” species are those that might soon become endangered). The goal of such organizations is to help a species recover to the point that it no longer needs to be listed as endangered.