"[7] Dr. D. Phillip Sponenberg, equine veterinarian at Virginia-Maryland Regional College of Veterinary Medicine, agreed, noting, "[These animals] don't exist anywhere else.

Nonetheless, both agencies responded to political pressure to act, and they began to remove hundreds of thousands of feral horses from federal property.

From 1934 to 1963, the Grazing Service (and from 1946 onward, the BLM) paid private contractors to kill mustangs and permitted their carcasses to be used for pet food.

[12] However, in 1961 President John F. Kennedy ordered the United States Department of the Interior to implement measures to stop soil erosion on federal land.

[13][14] Fearful that the horses were not going to be stabled but that the roundup was a prelude to slaughter of the entire herd, in 1966 Johnston began a letter-writing and public relations campaign against the BLM.

[16] Others who wanted to protect the herd included ranchers and the people of nearby Lovell, Wyoming, who not only considered the horses as part of Western heritage but also as a major tourist attraction.

[14] The ISPMB and its allies proved highly effective in raising public awareness of the issue and building political support for their efforts, and in 1966 BLM suspended its plans for the roundup.

On September 9, 1968, Secretary of the Interior Stewart Udall formally established a Pryor Mountains Wild Horse Range of 33,600 acres (136 km2).

[2] Montana's senior senator, Mike Mansfield, was so elated that he published Udall's order scrapping the BLM plan in the Congressional Record.

[37] Concerned about these practices, and about continuing horse hunts in unprotected areas, Johnston and her group began working to pass federal legislation to protect feral horses throughout the U.S.[36] She was joined by a number of prominent people, including country music singer Judy Lynn, Gunsmoke actress Amanda Blake, and Manchester Union Leader publisher and conservative William Loeb III.

[37] On December 18, 1971, President Richard M. Nixon signed into law the Wild and Free-Roaming Horses and Burros Act of 1971 (WFRHBA), which 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.

[39] The WFRHBA gave jurisdiction over challenges to BLM and Forest Service management of feral horses and how the act is implemented to the Department of the Interior's Board of Land Appeals.

The WFRHBA left range management policy unresolved in many respects, although it did specify that BLM and the Forest Service consult with state wildlife agencies.

[46] In November 1971, BLM announced a major effort to save the Pryor Mountains herd from starvation after a poor summer growing season left vegetation stunted on the range.

[48] The program took advantage of provisions in the WFRHBA to allow private "qualified" individuals to "adopt" as many horses as they wanted if they could show that they could provide adequate care for the animals.

While conceding that federal law protects the animals, these individuals also argued that economic needs (like livestock grazing) should take precedence over the horses.

480 U.S. 951 (1987), the United States Court of Appeals for the Tenth Circuit said that a wild animal was not an "agent" of the federal government and hence could not be found guilty of "taking" the ranchers' leased grass or water.

[56] Pursuant to the 1978 amendments, BLM established 209 "herd management areas" (HMAs) where feral horses existed on federal land.

In 1992, equine geneticist Dr. E. Gus Cothran ran genetic studies on the herd, and concluded that their primary bloodline descends from Spanish Barbs.

[87] The animals exhibit a wide range of solid colors, including bay, black, chestnut, dun, grullo, and blue or red roan.

[87] The head is convex or straight (the "Roman nose" identified by horse breeders), with wide-set eyes, hooked ears, and a broad forehead that tapers well to the muzzle.

[8] BLM counts the herd visually about every four years by flying over the range, reporting on each animal found, and using statistical methods to correct for historic undercounting and other problems.

[8][92] In 1990, the Government Accountability Office (GAO) issued a report highly critical of BLM's wild horse management programs.

The GAO concluded that the BLM had little scientific basis for deciding what the range-carrying capacity was or how many horses should be removed to attain ecological equilibrium or restoration.

[93] Furthermore, the GAO found that the BLM had not reduced livestock grazing or engaged in range management activities to improve the carrying capacity of the land.

[92] The Cloud Foundation and Front Range Equine Rescue, both feral horse advocacy groups, challenged the roundup in federal court.

[51] In the fall of 2010, BLM issued a set of draft strategy documents for operating its wild horse programs, and solicited public comment on the plans.

[103] After receiving numerous comments, BLM said in February 2011 it would quicken the pace at which it revised its roundup procedures, use of fertility control drugs, and wild horse and burro range land management.

[105] The range can also be accessed from Laurel, Montana, by traveling south on U.S. Route 310 and taking the Forest Service gravel road to Dryhead Overlook.

[80] Those with four-wheel drive vehicles can take the rutted dirt road through the forest to Penn's Cabin, which is another good horse viewing spot.