The Wild and Free-Roaming Horses and Burros Act of 1971 (WFRHBA), is an Act of Congress, signed into law by President Richard M. Nixon on December 18, 1971. The act covered the management, protection and study of "unbranded and unclaimed horses and burros on public lands in the United States."

A feral animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some cases, contributed to extinction of indigenous species. The removal of feral species is a major focus of island restoration.