WASHINGTON — Few images evoke the American West the way a wild horse does, running free across rangeland with its mane blowing in the wind.

From Westerns to music videos to beer commercials, a galloping horse is visual shorthand for freedom, vitality and self-sufficiency.

But in reality, wild horses can pose a problem to their local ecosystems, as growing herds forage and trample their way across large swaths of territory. Recent changes to federal policy have left several Indian tribes, including the Confederated Tribes of Warm Springs, with more wild horses than their reservations can support, and limited options to get rid of them.

In 2006, Congress eliminated funding for inspection of horse slaughterhouses, effectively ending all domestic butchering of horses.

Although horsemeat is not embraced in the U.S., it is eaten in other countries, and during 2006, the last full year they were operational, three American slaughterhouses killed more than 105,000 horses and exported 17,000 metric tons of horsemeat valued at $65 million, according to a 2011 report on wild horses by the Government Accountability Office.

Horses continue to be slaughtered in Mexico and Canada, but the glut of horses exported from America has driven down prices, especially on the lower-valued horses that are most often butchered for meat. The combination of longer distances to transport horses and lower sale prices have made it less economically viable to remove excess horses, and herds on tribal lands have grown as a result.

Last week, Jason Smith, president of the National Tribal Horse Coalition, wrote to members of the Senate Appropriations Committee, urging them to restore the funding for inspectors that would reopen American slaughterhouses.

“Some reference horses of this nature as ‘wild,’ but that description is neither biologically or historically accurate; these horses are feral,” Smith wrote.

There are almost 5,000 feral horses on the Warm Springs Reservation, 75,000 across the Navajo Nation in Utah, Arizona and New Mexico, and more than 12,000 on the Yakama Reservation in Washington State.

“Through both overgrazing and trampling these animals are doing severe environmental and ecological damage to that Tribe’s homelands,” noted Smith, who is the range manager at Warm Springs. “The effects are profound. Native deer and elk, that once flourished and which provide sustenance to the Yakama people on lands the U.S. promised to protect, are now becoming scarce in many parts of the reservation.”

Range degradation and the lack of vegetation is also undermining restoration efforts for salmon in streams and sage grouse on rangelands, he said.

Herds can grow up to 20 percent annually, meaning they double in size every five years.

“It’s just like a cattle herd. People manage their herds by culling,” Smith told The Bulletin. “If you don’t have enough (resources) for them, the next thing you know your livestock has an undesirable quality.”

With no outlet for the excess horses, fewer families are tending them as livestock, which only makes the problem worse.

“Since this (ban) came about, it took a few years to settle in, but eventually it’s all expense and no return on the horses,” Smith said.

As he noted in his letter, the feral horses are not pets or companions, and while ending domestic slaughtering of wild horses may seem humane, the new federal policy has unintended consequences.

“It’s just going to make the problem worse, and prolongs the agony of it all,” he said.

Overpopulation leads to starvation for the horses, and horses often roam onto roads and highways, creating a traffic hazard, he said.

In addition, tribal land has become a dumping ground for people who can no longer afford to feed their own horses but have no other way to get rid of them.

“People just get rid of the problem, and let it be someone else’s problem,” Smith said. “We’re just trying to be able to manage our herds, and we can’t do that right now, the way things are.”

By contrast, the Bureau of Land Management actively culls herds of wild horses on public lands and keeps horses in federally funded holding facilities. Sometimes the horses are sold, but often they remain indefinitely in the BLM facilities.

Earlier this year, the BLM established a limit of four animals per buyer for each six-month period following media reports that since 2008, a single buyer in Colorado has purchased more than 1,700 wild horses from the BLM — almost 70 percent of all horses sold by the agency during that period. The buyer, Tom Davis of La Jara, Colo., cannot account for the whereabouts of all those horses, many of which are suspected to have been sold to Mexican slaughterhouses, according to a joint investigation by Propublica and the Colorado Springs Gazette.

According to BLM estimates, 31,500 wild horses live on public lands overseen by the agency in the West. This is about 11,000 more than the total the agency believes the rangelands can support.

Earlier this month, both the House and Senate appropriations committees voted not to fund inspectors, which would effectively continue the “no domestic slaughterhouse” policy.