In 1971, wild horses and burros were found roaming across 53.8 million acres of Herd Areas (HAs), of which 42.4 million acres were under the BLM's jurisdiction. Today the BLM manages wild horses and burros in subsets of these HAs, known as Herd Management Areas (HMAs) that comprise 31.6 millionacres, of which 26.9 million acres are under BLM management.
The Pryor Mountain Wild Horse Range (PMWHR) HMA was originally created through Secretarial Order in 1968 and 1969 for the “protection and management of wild horses, wildlife, watershed, and recreation, archaeological and scenic values”. The PMWHR is managed under the Wild Free-Roaming Horse and Burro Act of 1971 with three agencies involved with its management; the Bureau of Land Management (BLM), USFS, and National Park Service. This effort is led by the BLM.
The PMWHR is located in the southeastern portion of Carbon County Montana, and north portion of Big Horn County Wyoming. The area is approximately fifty miles south of Billings Montana, and ten miles north of Lovell Wyoming. The area is high in diversity and complex in nature. Elevations range from 3850 feet to 8750 feet above sea level. Annual precipitation varies with elevation with six inches of average annual precipitation in the lower elevations to upwards of twenty seven inches in the alpine high elevation. Plant communities also vary with elevation and precipitation from cold desert shrub to sub-alpine forests and meadows. Much of the land is classified as “Northern Intermountain Desertic Basins” a cold desert considered an isolate of the Great Basin. The high elevation is in “Central Rocky Mountains” with a large swath of transition zone between.
The origin of the wild horses within the PMWHR is not entirely known. There is much supposition as to their origin. Many claim the horses are descendents of animals the Crow Indians obtained from the Spanish or other tribes in contact with the Spanish. The Crow Indians were known to have horses by the 1700s and to inhabit the Pryor Mountains before European settlement. Others claim the horses have been there forever. The trapper William Hamilton explored the Pryor Mountains in 1848 and did not describe the presence of wild horses. By the early 1900s wild horses within the Bighorn basin were well documented.
Most likely the wild free-roaming horses inhabiting the PMWHR are descendants of numerous founding stocks. . Genetic tests conducted by Dr. Gus Cothran concluded the Pryor horses aredescendants of New World “Spanish” breeds (saddle type horses) and related to European “Spanish” breeds and descended from light racing and riding breeds. Some of the Pryor horses carry a rare allele variant Qac that is traced back to original New World “Spanish” type horses that were developed from the original Spanish and Portuguese (Iberian) horses that were brought to the Americas, conversely these horses also carry no genetic markers other horse breeds don’t have.
The Pryor horses tend to be smaller than the average wild horse at about 13 hands and 800 pounds . Many exhibit striping on legs and have dorsal stripes Low set tails, concave (dished) faces, and pointed ears. Colors tend to be Dun, Buckskin, Grulla, Blue and Red Roan, Bay, Black, Brown and Palomino.
The Approroiate Management Level is 90-120 wild horses (excluding current years foal crop) The herd is managed through a combination of removals, fertility control, and natural means. A robust field darting fertility control program is in place with up to 90% of the mares under treatment. The herd is managed for managed for an even sex ratio of 50% mares 50% stallions while preserving “Spanish traits”, individual bloodlines Colors Managing 5-10 year olds as the primary breeding core to retain genetic diversity.