RENO (AP) -- Conservationists say federal rules that allow livestock grazing and oil and gas development across 25 million acres of public land in the West are illegal because they fail to acknowledge the harm being done to sage grouse.

A lawsuit recently filed in federal court accuses the Bureau of Land Management of violating two major environmental laws and its own regulations by allowing commercial activities to continue on those lands in Nevada, Idaho, Montana, Wyoming, Utah and California.

But in a switch in strategy, the environmentalists aren't asking a judge to immediately halt those operations. They want to talk, and they think they may have a willing listener in the new Obama administration.

"What we are after is finding a way to do things differently than in the past and better manage these public lands into the future,'' said Laird Lucas, a lawyer for the Western Watersheds Project, which filed the suit.

"The next 20 years are going to be really critical, not just for sage grouse, but for the whole sagebrush ecosystem,'' he said. "Getting an injunction that creates a crisis in the short term doesn't really serve that role.''

Since taking office, President Obama has distanced himself from several Bush administration policies on the environment and suspended some administrative orders Bush signed in the waning days of his term that could lead to the easing of protections for threatened wildlife on federal land.

The change in administrations prompted the new approach from the Idaho-based environmental group that has spent much of the past eight years in court battling land use rules adopted by the BLM and Forest Service under the Bush administration.

"The Obama White House has a very strong and public commitment to applying science-based decision-making for natural resource issues,'' said Jon Marvel, the group's director.

"We want to show the Obama administration the misdeeds of the Bush administration in the hope they will understand and be interested in correcting those,'' he said.

Kendra Barkoff, press secretary for Interior Secretary Ken Salazar, said Friday ``we are in the preliminary stages of litigation and as a result can't comment.''

Ranchers and drillers said the suit is part of an effort to keep livestock, energy development and other commercial activities off an area of the West bigger than the state of Indiana.

The Wyoming Stock Growers Association and the Petroleum Association of Wyoming have joined the government in seeking to dismiss the suit. A hearing on one of those motions is scheduled in Boise Thursday.

"They are trying to tie up 25 million acres and close it down to livestock operators altogether,'' said Ronald Opsahl, a lawyer for the Mountain States Legal Foundation, which represents the two Wyoming groups.

"As far as the scope of this case, it has to be unprecedented,'' he said. "I've never seen one lawsuit challenge 18 resource management plans in six states.''

So far, Justice Department lawyers representing the BLM, have restricted their legal arguments primarily to matters of jurisdiction. Deborah Ferguson, assistant U.S. attorney for Idaho, said each of the 18 plans being challenged should be handled separately in U.S. courts in each of the six states.

The focus of the lawsuit is a chicken-sized game bird -- mottled brown, black and white -- found on sagebrush plains and high desert from Colorado to California and into southern Canada. The government estimates as many as 16 million sage grouse inhabited the West in the early 1800s when they were first observed by Lewis and Clark. Today their numbers have dwindled as low as 100,000, according to a U.S. Fish and Wildlife Service census in 2005.

Wildfires, development and industry have cut steadily into their habitat, now estimated to be about half of what it once was when the birds ranged from Kansas to Washington and into the Dakotas.

North Dakota's sage grouse population is limited to the far southwestern corner of the state, in Golden Valley, Slope and Bowman counties. A record-low number of male sage grouse in breeding grounds prompted biologists to close last fall's hunting season.

At issue in the lawsuit is the BLM's National Sage Grouse Habitat Conservation Strategy. The agency adopted it in 2004 as an interim plan to help protect the bird and guide management of federal rangeland while the U.S. Fish and Wildlife Service considered whether to protect the sage grouse under the Endangered Species Act -- a move ex-Interior Secretary Gale Norton predicted would have a more significant economic impact on the West than did the listing of the northern spotted owl in the early 1990s.