HAGERMAN, Idaho — Some in Idaho worry that efforts to ban the slaughter of horses for human consumption will lead to more people letting unwanted horses free, leaving them to die miserable deaths and exacerbating conflicts with ranchers who count on the sparse forage of the West's high desert for their cattle.

This year, Congress passed legislation that bans funding for inspection of horses for human food, making it temporarily impossible for plants to market horse meat.

Additional bills would prohibit outright the movement and slaughter of horses for human food and other purposes.

Officials including U.S. Sen. Larry Craig, R-Idaho, and brand inspectors point to an overabundance of mustangs on the open range and say that banning horse slaughter for human consumption will only make things worse. For instance, the U.S. Bureau of Land Management announced plans Wednesday to gather about 1,700 wild horses from the Nevada range, citing ongoing drought, dwindling forage and an overabundance of animals in three herd management areas.

"All these do-gooders that want this slaughter thing stopped — they think it's so inhumane. You're going to have horses suffering 10 times as much," Larry Hayhurst, the state brand inspector in Meridian, told the Twin Falls Times-News. "There's no out for these unwanted horses. They are going to turn them out."

Animal protection groups have been trying for years to get Congress to pass legislation prohibiting the slaughter of horses for human consumption.

Now, they're counting on two bills presented in Congress, the Senate version sponsored by Sens. Mary Landrieu, D-La., and John Ensign, R-Nev., to close the final loophole in the U.S. slaughter ban. Current laws prohibit the domestic slaughter of horses but allow groups such as the Twin Falls Livestock Commission to export horses for slaughter to Mexico and Canada.

Nancy Perry, vice president of government affairs for the Humane Society of the United States, argues that it's absurd to think a final ban would lead to a wave of people opening their stock gates and letting unwanted or old, broken-down horses flee into the desert. She said the cost of a humane euthanasia is well within the budget of most horseowners.

"Most people who own a horse can actually afford to have the vet come out and give them a really painless injection," Perry said. "I think a lot of it is people needing to take responsibility for their property."

Her group has documented instances where horses bound for slaughter were abused. In Juarez, Mexico, a horse survived multiple stabbings attempting to sever its spinal cord. And in Canada, the Humane Society discovered a case where a horse continued to thrash after it was shot in the head with a captive bolt.

But Craig said with the economy souring, he's concerned more people will dump their horses on rangeland rather than euthanize them.

"Particularly in the West, we are witnessing an increase in the number of unwanted horses dumped on public or private rangelands," he said late last year, according to congressional records, adding that rescue organizations are "stretched to capacity and we expect an increase in need."

Since the recent restrictions, horses sold for slaughter each month in Twin Falls have fallen by half, said Bruce Billington, owner of the Twin Falls Livestock Commission. Nationwide, the number of American horses slaughtered dropped 20 percent, from 133,912 in 2006 to 106,963 in 2007, according to the U.S. Department of Agriculture.

About a fourth of the 200 horses sold each month in Twin Falls are purchased by representatives of Canadian and Mexican slaughterhouses, Billington said. Some would likely be set loose or, if kept, be underfed and otherwise abused, if the outright ban goes through, he said.

Horses that survive release would thin vegetation, rangeland managers with the BLM say. Some horses would adapt, while others with hooves requiring trimming would become lame. Others would die of thirst, not knowing how to find water.

"It's going to make people into criminals," Billington said. "They will turn them out in BLM land."