The Pryor Mountain mustang is a substrain of mustang considered to be genetically unique and one of the few strains of horses verified by DNA analysis to be descended from the original Colonial Spanish horses brought to the Americas by the Spanish. They live on the Pryor Mountains Wild Horse Range located in the Pryor Mountains of Montana and Wyoming in the United States, and are the only mustang herd remaining in Montana, and one of fourteen in Wyoming. They are protected by the Wild and Free-Roaming Horses and Burros Act of 1971 (WFRHBA) and managed by the Bureau of Land Management (BLM), who has set the optimum herd number at 120 animals. Genetic studies have revealed that the herd exhibits a high degree of genetic diversity and a low degree of inbreeding, and BLM has acknowledged the genetic uniqueness of the herd. Pryor Mountain Mustangs are relatively small horses, exhibit a natural ambling gait, and domesticated Pryor Mountain mustangs are known for their strength, sure-footedness and stamina. The Pryor Mountains Wild Horse Range is one of the most accessible areas to view feral horse herds in the United States and tourism to the area has increased in recent years.
Feral horses are documented as living in the Pryor Mountains by the early 1700s, although they may have been there since the late 1600s. By the late 1800s, thousands of feral horses inhabited the area. In the early 1900s, many of the unbranded horses were rounded up, to allow domesticated livestock to graze the range without competition, and by 1964 there were only around 200 horses left. In 1964, the BLM announced that the horses would be removed altogether, to the outrage of the public. The controversy continued until 1968, when the BLM was legally stopped from removing all of the horses, and the area declared a Wild Horse Refuge. After the 1971 signing of the WFRHBA, the BLM spent the 1980s and 1990s conducting population studies and developing management and adoption policies; during this time, numerous genetic studies were also completed.
The BLM management of the herd has included improvements to the range to give the horses additional access to water, and numerous roundups that have resulted in the removal and adoption of hundreds of horses to private individuals, including 57 horses in 2009, 45 horses and foals in 2012, and 18 in 2015. Once again, every horse captured was adopted. Another gather was slated to begin in September 2018, with 17 horses identified for removal. However, it was cancelled amidst concerns that it would have a detrimental impact on herd genetics.
Characteristics
The Pryor Mountain mustang has a very specific conformation type. The breed generally stands high, with an average of .Dutson, p. 209Lynghaug, p. 106 The horses weigh on the range, and more if raised in captivity. They exhibit a wide range of solid colors, including bay, black, chestnut, dun, grullo, and blue or red roan. Buckskin coloring is rare but does occur, and pinto coloring can be minimally expressed. The dun-colored horses on the range exhibit primitive markings such as dorsal stripes, transverse stripes across the withers, and horizontal "zebra" stripes on the back of the forelegs. The Pryor Mountains horse's body is heavy, with strong bones. Manes and tails tend to be long, and the horse's winter coat is very heavy and often curly. The head is convex (sometimes called a "Roman nose) or straight, with wide-set eyes, hooked ears, and a broad forehead that tapers well to the muzzle. The front teeth meet evenly, the upper lip is usually longer than the lower, and the nostrils are small and crescent shaped. The neck is medium in length, and most of the animals have only five lumbar vertebrae (an anatomical feature common in primitive horses)—although some have a fifth and sixth vertebrae which are fused. The horse's shoulders are long and sloping, the withers are prominent, and chests are medium to narrow in width. The croup is generally sloped, and tail-set is low. The hooves are large and very hard.
Some Pryor Mountain mustangs exhibit a natural ambling gait. They are generally intelligent, strong, and sure-footed, and exhibit great stamina. Like all feral horses, they generally avoid human contact, are distrustful, and are easily spooked. However, once they are familiar with an individual, they can exhibit a strong social bond with that individual. Pryor Mountains horses can be broken and ridden, and trained to do any task a domesticated horse can perform. Trained Pryor Mountains horses have a calm temperament, and are alert on trails.
The horses form bands or "harems", in which a single stallion mates and controls a group of about six mares. Another eight to 10 "bachelor" stallions accompany the band at a distance, hoping to win control of it from the stallion or mate with mares.
History
Historians and scientists speculate that feral horses have lived on and near Pryor Mountains since at least the late 1600s.Singer and Schoenecker, p. 39. Tradition of the Crow people maintains that the horses came to the area by about 1725. The Eastern Shoshone also inhabited the region during the 1700s.Billings Field Office. Accessed 2011-06-07. Non-Indian explorers found native people in possession of large numbers of horses as early as 1743.Pomeranz and Massingham, p. 15.
Thousands of feral horses lived in the area by the time American pioneers began settling near the Pryor Mountains in the late 1800s.Cruise, p. 185 Between then and the 1930s, many domesticated horses were turned loose on the range, accidentally or on purpose; domesticated stallions were turned out to mate with mares on the range with the goal of producing cavalry remounts for the military. With passage of the Taylor Grazing Act of 1934, cattle and other horses were allowed to graze in the area, and by 1946, the BLM was formed. Through the 1940s, there were no protections for the wild horses on the range, and loose, unbranded horses were routinely rounded up so as to not compete with cattle for forage. Some were sold to slaughter, others kept for riding. However, with the passage of the Wild Horse Annie Act in 1959, motor vehicles were prohibited from being used to capture, harass or chase wild horses. By 1964, there were approximately 200 horses remaining in the area, which were seen as a "symbol of the Old West"Ryden, p. 239 by local citizens. That year, the BLM announced its decision to remove all horses from the Pryor Mountains and disperse the herd through public auctions, a move that was strongly opposed by the public. Public opposition to the plan succeeded in delaying any movement against the horses.
By 1968, the wild herd were concentrated mostly on BLM lands owing to previous roundups and construction of boundary fences. That year, the BLM again stated its intention to remove the herds, this time with the possibility of returning a small number (either 15 or 35) to the range. In response to the new announcement, the Pryor Mountain Wild Horse Association (PMWHA) was formed with the goal of preventing the roundup, and began working in concert with larger organizations such as the International Society for the Protection of Animals. The BLM argued that the horses were being removed because they were likely to starve, as they had overgrazed their environment,Ryden, p. 244 while the PMWHA argued the degradation of the range was not due to the horses and that in fact they were in no danger of starving.Ryden, p. 246 The organization further charged that the BLM was acting at the behest of other state and federal organizations who wished to see the horses removed, rather than acting in line with public opinion. The PMWHA was also concerned with the effect that the penning would have on the feral horses.Ryden, pp. 248–250
The battle over the Pryor Mountain herd moved to the national level on July 11, 1968, when ABC broadcast a special on the horses on the evening news. The public reacted with outrage,Ryden, p. 251 and the BLM responded that "no decision had yet been made regarding the horses."Ryden, p. 252 However, by the end of August, a trap to collect the horses had been completed. At the same time, the BLM was unresponsive to efforts by members of the public, senators and officials from the Humane Society of the United States to ascertain final plans regarding the horses. Because of this, court proceedings were begun, and on August 27, 1968, a US District Court judge made a decision that had the result of barring the BLM from removing the horses from the range.Ryden, pp. 254–256 On September 9, 1968, the Secretary of the Interior, Stewart L. Udall, declared the area inhabited by the Pryor Mountain mustangs as the Pryor Mountain Wild Horse Refuge (PMWHR), in a decision later noted in the Congressional Record.Ryden, p. 256 After the creation of the refuge the BLM appointed a committee to study the area and make recommendations regarding appropriate herd numbers. The committee, which met in late 1968 and early 1969, was made up of range and wildlife experts, local citizens interested in the herds and representatives from several federal, state and private organizations.Ryden, pp. 256–258 A boundary adjustment was made to the refuge, adding some land in Wyoming. The final report of the committee, submitted in June 1969, was that the horses were not in danger of starvation, that overgrazing was likely due to domestic sheep who utilized the land decades earlier, and that horses were the most likely of any species to be able to survive and thrive in the Pryor Mountain environment.Ryden, p. 259–61 On December 18, 1971, the Wild and Free-Roaming Horses and Burros Act of 1971 (WFRHBA) was signed into law by President Richard M. Nixon. The Act made it a crime for anyone to harass or kill feral horses or burros on federal land, required the departments of the Interior and Agriculture to protect the animals, required studies of the animals' habits and habitats, and permitted public land to be set aside for their use.Naughton, James M. "President Signs Bill to Protect Wild Horses on Federal Lands." New York Times. December 18, 1971. The Bureau of Land Management and Forest Service were jointly charged with responsibility for administrating the Act. The National Park Service was also involved in the management of the land. These federal agencies were limited to managing horses only on public lands where "wild horses were documented as being 'presently found' at the time of the passage of the Act in 1971."
Genetics