Wild Mustangs’ Origins at Heart of Dispute Over Their Future

Since 1971, when Congress declared them “living symbols of the historic and pioneer spirit of the West” and stopped the decimation of their dwindling herds, America’s wild horses have made a comeback.

Now, the government says, too many wild horses crowd the West’s meager grazing lands, and up to 10,000 animals are being held in corrals in Texas, Nevada and Nebraska, rounded up as “excess” and offered for adoption.

Although the Bureau of Land Management wants only 27,000 wild horses on public lands, more than 38,000 now run the open range of 10 Western states.

Among them are 120 horses and 30 foals tucked away amid the rust-colored dirt, sparse grass and tangled sagebrush of the Bighorn Canyon.

In 1968, after decades of lobbying by outraged protectors, the secretary of the Interior declared part of the Pryor Mountains to be the first federal wild horse range. Today the refuge, which straddles the Montana-Wyoming border, encompasses 46,811 acres. It is administered by the BLM.

Subsequent refuges have been established at Little Book Cliffs in Colorado and Nellis Air Force Base, Nev.

At the century’s turn, 2 million wild horses roamed 11 states. But they were relentlessly hunted by cowboys and “mustangers” in trucks and airplanes, then slaughtered for pet food or glue. Such roundups were depicted in a 1961 film, “The Misfits,” with Clark Gable and Marilyn Monroe.

Congress in 1959 outlawed the use of fixed-wing aircraft or motor vehicles to capture wild horses. A 1971 law made it a criminal offense to harass or kill wild horses on public lands.

When the law was passed, the horses numbered fewer than 17,000. Now the size of the protected herds has ranchers and animal activists, with the BLM between them, at loggerheads over what to do next.

The Pryor Mountain herd illustrates the arguments of the two factions, which often boil down to whether the horses are near-pure descendants of the mustang or pests.

The herd comes in the colors of the land--blue and red roans, sorrel, black and grulla , the Spanish term for mouse-colored. Like all wild horses, these have formed bands with lead stallions and harems of mares.

Their origins are steeped in controversy; even the term “wild” is disputed.

Their champions say they are the closest thing left in this country to pure mustangs, the horses brought here in the 1500s by the conquistadors. They say the isolation of deep canyons has allowed little outside blood to taint the herd and it should be protected.

Foes scoff at the designation “mustang,” which comes from mestenos, a rough translation from Mexican Spanish meaning “strayed.” They say that the horses have little or no blood passed down from those Spanish runaways and that they are nuisances, not national treasures. They begrudge the horses’ grazing rights on public lands.

The refuge is named for Sgt. Nathaniel H. Pryor, who accompanied Meriwether Lewis and William Clark on their exploration of the West. Clark’s journal of August, 1806, describes Pryor’s losing a herd of horses in what is now the Crow Indian Reservation bordering the Pryor Mountains.

The expedition horses came from trade with Indians and were described as “particularly slippery and high-spirited animals” and “elegant.”

Ancestry is at the heart of the argument over inbreeding. The latest furor concerns the BLM’s proposal to introduce new stock to ward off disease and genetic weaknesses.

Those who doubt the herd’s mustang ancestry believe the “real” Pryor Mountain mustangs were killed in the 1920s and ‘30s in favor of livestock and that today’s herd is descended from horses turned out by ranchers in the Depression.

But some Pryor Mountain horses still lack the sixth lumbar vertebra of domestic horses, or have the fifth and sixth vertebrae fused in the spinal column. The small, compact mustangs had only five lumbar vertebrae.

And many are buckskin in color, with dark stripes down their backs and tiger stripes around their front legs, markings that resemble those of early mustangs.

Lynne Taylor, the BLM manager at Pryor, has been a cowboy most of his life and has worked with the herd since 1971.

He is charged with keeping it at 121 head, the number the BLM decided could successfully forage off beautiful but barren land that sometimes gets as little as five inches of rain a year.

Taylor said he knows the recent ancestry of every animal. He has compiled pedigrees for Dr. Oliver Ryder, a geneticist at the San Diego Zoo who specializes in endangered species and has visited the Pryor range.

“In small populations that are genetically closed . . . there is, on average, an increased vulnerability,” said Ryder, adding, however, that “the Pryor herd appears to do very well in a harsh environment.”

Ryder said in a telephone interview that based on Taylor’s data, “there’s no question inbreeding is occurring, and without new migrants it’s going to increase rapidly in succeeding generations. . . . Thirty percent of all the genes traced their way back to one male that Taylor named The Black Stud.

“In the long run,” he added, “there’s a definite risk in having genetic diseases.”

Traits attributed to the Spanish mustang can show up in horses today, said Ryder, “either through genetic background or by chance, by the throw of the dice.”

Hope Ryden, an author and wild horse advocate, has visited the Pryor Mountains since 1967 and has written two books on the herd.

She questions the BLM’s data and is adamantly opposed to the introduction of new horses.

“It’s a terrible idea,” Ryden said in a telephone interview from her home in New York. “There isn’t any pure herd of mustangs left, but the Pryor Mountain horses come closest to them.

“To say the settlers added to this herd is ridiculous. I knew Bess Tillett, who was 4 years old when her family was the second one to come into the Pryor country in 1894. She said the first thing her father did was go mustanging because the horses were so pleasing. The pioneers’ horses weren’t being cut loose; it was going the other way.”

Ryden said she rode a Pryor Mountain horse owned by the Tilletts in the late 1960s, on a cattle drive.

“I was doing all sorts of cowboy things I never thought I could do, such as flushing calves out of brush and keeping them in line,” she said. “I was quite proud of myself, but I got saddle sore and got off for a while. My horse just kept right on doing all the things I thought I’d been doing.”

She tells the story, she said, to illustrate her contention that the Pryor Mountain horses retain the buffalo herding traits the Indians taught their Spanish mustangs.

“That particular herd has more colors than any I’ve ever seen,” she said. “The idea of dumping just anything in there is appalling. There would no longer be historical and biological meaning to the place. Why mess it up when it’s working so well?”