Most of the bird’s habitat — sagebrush steppe — is on land administered by the BLM.
Greater Sage Grouse
The Interior Department had revised those plans this month as part of President Donald Trump's oil and gas efforts.
The new plans are expected to remove the most protective habitat designations for about 13,000 square miles of public land.
The Interior Department plans to ease restrictions on oil and natural gas drilling and other activities across millions of acres in the American West.
The Fish and Wildlife Service said only about 4,700 Gunnison sage grouse remained in 2014.
Sen. Michael Bennet and Gov. John Hickenlooper asked the government to stop plans for oil and gas drilling on habitat for the greater sage grouse.
A U.S. judge ruled that federal wildlife officials had illegally denied protections for the bird in 2015.
Some governors in the U.S. West say a new Trump administration directive threatens to undermine a hard-won compromise aimed at saving a beleaguered bird scattered across their region.
There are between 200,000 and 500,000 sage grouse in the West, down from a peak population of about 16 million.