For nearly a century, the Department of Agriculture’s Sheep Experiment Station has grazed over 6,000 sheep on 100,000 acres of public land in Montana and Idaho west of Yellowstone National Park. Yet the research center has never formally assessed its ecological impact on this mountainous habitat for native wildlife species.

This month, in response to a lawsuit, the Department of Agriculture (USDA) finally agreed to do so.

The research station -- whose mission is to find ways to increase meat and wool production as well as enhance the ecological sustainability of the sheep industry -- is part of the federal department’s research branch, Agricultural Research Services (ARS).

The agreement settles a 2007 lawsuit against the research station, the USDA, ARS, and the U.S. Forest Service by the Center for Biological Diversity and Western Watersheds Project.

The conservation groups claim that the research station has been violating federal law since 1970, when the National Environmental Policy Act began requiring government agencies to assess the ecological impact of their projects.

The research station had believed it was exempt from NEPA under an exclusion for research-oriented programs, says Andrew Hammond, regional director for ARS.

However, categorical exclusions are supposed to be opened to public comment, says Marc Fink, an attorney for the Center for Biological Diversity. The station, to Fink’s knowledge, never received public comment.

“I think it speaks for itself that (the agency) settled,” says Michael Robinson of the Center for Biological Diversity. “If they weren’t violating the law, they wouldn’t have settled.”

“We thought we were operating correctly, but we agreed just to be on the safe side,” counters Gregory Lewis, lead researcher at the station.

A Department of Agriculture attorney declined to comment on the lawsuit.

Conservationists filed suit because they believe the presence of the domestic sheep threatens native populations of bighorn sheep, grizzly bears, gray wolves, and other predators.

“The problem is domestic sheep,” says Jon Marvel, executive director of the Idaho-based Western Watersheds Project. “We can’t recover bighorn sheep to their native habitat unless domestic sheep are removed. And which are more important?”

Historically, bighorns ranged the scattered BLM, Forest Service, and research station allotments, but they have not been found there recently, says Lewis. Staff members search the area daily for signs of the bighorns, he says; if any were found, the domestic sheep would be moved.

The bighorn population in central Idaho fell from about 3,850 in 1990 to 1,710 in 1998, according to Idaho Fish and Game biologist Dale Toweill. He estimates current numbers at about 2,000. Bighorns may once have numbered in the millions in North America.

The conservation groups are also concerned about large predators in the area, which includes 16,600 acres in the Centennial Mountains on the Montana-Idaho border.

“The Centennial Mountains provide a corridor for migration of larger wildlife like grizzly and wolves,” says Jon Marvel. “Large predators have used this very land, and having sheep there puts the predators at risk of being killed for attacking livestock.”

Researchers, however, say they rarely have any troubles with predators, and grizzly bears have never been killed in the area. “We have really strict policies on killing wildlife, and we don’t unless it’s a last-ditch effort,” says Lewis.

Wildlife Services is the USDA agency charged with the management of problem predators. Todd Grimm, the agency’s regional supervisor, says aerial and ground hunting, traps and snares are used to control coyotes on the station’s land. Poisons, such as spring-loaded cyanide capsule devices, were not used in the past year, he said.

Although no black bears or mountain lions were killed last year, it would be normal to kill one or two in a year for livestock protection, he says.

Wildlife Services tries to haze predators like coyotes by shooting at them, says Lewis, but, “If (coyotes) don’t go away, and they are killing lambs, then you have really no other choice.”

If nothing else, Marvel hopes the ecological assessment will make the research station more transparent.

“One of the problems with this particular function of the Agricultural Research Service is it’s heavily concealed in a veil of secrecy. It’s almost impossible to talk to them. (The assessment) will finally shine the light of day on what they’re doing.”

The author is an intern for High Country News.