Citing global warming, environmental groups are asking a federal judge to call a halt in Wyoming to one of the largest coal-mining plans ever approved by the U.S. government.

In a lawsuit filed on Wednesday in U.S. District Court in Washington, D.C., the Sierra Club and WildEarth Guardians said the federal Bureau of Land Management failed to consider the impact of greenhouse gases that will be emitted when coal from four government mineral leases in Wyoming is burned in power plants across the nation and in Asia.

Selenium contamination from a phosphate mine in southeastern Idaho is linked to fish deformities such as two-headed trout, and the problem would worsen if discharge limits were eased, a new government report found.

The findings come as Smoky Canyon Mine, run by the J.R. Simplot Company near the Wyoming border, is asking the Idaho Department of Environmental Quality to relax restrictions on the amount of selenium that the mine may drain into tributaries of the Snake River, a world-class trout stream.

Conservationists asked a federal court on Monday to stop wolf hunts under way in Idaho and Montana until judges rule on an appeal that seeks to restore federal protections to the animals in the two states.

The Alliance for the Wild Rockies and others told the U.S. Ninth Circuit of Appeals that more than 200 wolves have been killed in Idaho and Montana so far this year from a population estimated at between 1,300 and 1,600.

The U.S. government has proposed lifting federal protection from wolves in the state of Wyoming which would allows unregulated killing of the animals in most of the state.

The proposal under a state wildlife management plan would require Wyoming to maintain at least 150 wolves statewide, including packs that roam Yellowstone National Park, out of a total statewide population estimated at 350 animals.

A warming climate is imperiling the iconic wildlife and landscapes in the Yellowstone National Park region, two environmental groups said in a study.

The report by Rocky Mountain Climate Organization and Greater Yellowstone Coalition released on Tuesday shows temperatures in the past decade in the Yellowstone area have exceeded the rate of warming worldwide compared to the 20th Century average.

Conservation groups asked an appeals court on Monday to strike down a move by Congress to strip more than 1,500 wolves in Idaho and Montana of federal endangered species protections.

In a petition to the U.S. Ninth Circuit Court of Appeals, the groups sought to overturn a ruling last week by a federal judge that found Congress did not exceed its authority in April when it allowed a measure removing wolves from the endangered species list in Idaho and Montana.

Exxon Mobil said on Friday that a pipeline that failed two weeks ago, leaking oil into the Yellowstone River, routinely transported a heavier and more toxic form of crude than the company and federal regulators initially acknowledged.

The Silvertip pipeline carries so-called tar sands crude from Alberta, Canada, as do the U.S.

Water downstream from a ruptured Exxon Mobil pipeline that leaked oil into the Yellowstone River showed no detectable levels of toxic petroleum chemicals, according to U.S.

The greatest threat to the northern spotted owl, an imperiled bird at the center of a decades-old environmental clash in the Pacific Northwest, is no longer the timber industry -- it's another owl.

The federal government says it plans to launch a program to kill or otherwise remove hundreds of barred owls -- originally from the East Coast -- that are overtaking the spotted owl's natural range i

The state of Idaho has authorized sheriff's deputies in a tiny mountain town to kill wolves blamed for preying on pets and elk, a spokesman for the state fish and game department said on Tuesday.

The move marks the second of two wolf kills sanctioned by Idaho less than two weeks after federal protections were lifted from most wolves in the Northern Rockies and states, including Idaho and Montan