According to archeological evidence, several species that were ancestors of the modern horse were present in North America as long ago as 2.5 million years ago. Genetically similar species of the horse died out in America about twelve thousand years ago. Spaniards reintroduced the horse in the 16th century; some escaped as feral animals and are the ancestors of the wild horses that still roam the wild lands of the west today. The Bureau of Land Management currently protects and manages wild horses and burros in balance with other public resource values on 177 herd management areas across 26.9 million acres of public lands. Feral horses run free but populations of horses are controlled by the BLM with a capture-adoption program at stations ranging from Illinois to California and Texas to Oregon.
Whether feral horses should be allowed to run on public lands is a continuing matter of controversy. Horses on open range compete for grass and forage with cattle who are allowed to graze under government contract – so ranchers are frequently opposed to wild horses having free range. Some environmentalists oppose allowing horses to roam freely because of the riparian damage they do, arguing that, because horses have been absent from the landscape for ten thousand years, they are not consistent with the ecosystems that have more recently evolved. Others argue that, since horses were present until they were killed off, presumably by natives, that they belong to the landscape. Others constitute a lobby that simply loves the idea of horses roaming the landscape since that was what the early pioneers found in the eighteenth and nineteenth centuries. The argument continues. Meanwhile, under the BLM program, prisoners in some states are charged with the taming of the captured wild horses which are then put up for adoption.