The Bureau of Land Management has been forced to postpone putting up a few hundred wild horses, most of them recently removed from northern Utah’s Onaqui Mountains, after mustangs at the BLM’s Delta corral tested positive for a highly contagious form of equine distemper.
Known for their colorful markings and tolerance of people, the Onaqui horses are among the most visible and well-known free-roaming equines in the West. As a result, they are frequently photographed and were formerly the subject of an experimental fertility-control project in which a contraceptive was administered to mares with dart guns.