Conservation groups are taking the U.S. Bureau of Land Management to court for leasing 179 square miles in Wyoming for oil and gas development.
They claim the agency broke the law when it approved leases in June in areas identified as key migration routes for struggling mule deer and pronghorn populations.
Julia Stuble, Wyoming state director for The Wilderness Society, said the lawsuit is an effort to defend Wyoming’s migrating big game and the hunters who rely on them.
"Mule deer, elk, antelope, they require undisturbed stopover sites in these corridors for foraging during the long-distance journeys that they take between winter and summer range," Stuble explained. "The agency violated its own regulations that require giving preference to leasing away from these crucial habitats."
Pronghorn herd numbers in the leased parcels are between 37% and 66% below targets, according to the lawsuit. Mule deer numbers are 25% to 62% below targets.
The Petroleum Association of Wyoming disputed the lawsuit’s claims and said further environmental reviews would take place before drilling actually began. The BLM has not yet responded to a request for comment but the Trump administration has long argued opening public lands for fossil fuel extraction is necessary to achieve energy dominance.
Stuble noted more than 81% of BLM-managed lands across the West are already open for oil and gas leasing. She argued the agency has prioritized drilling over all other uses, which goes against the BLM’s legal obligation to balance multiple uses of public lands. She believes balance is what most people in Wyoming want to see.
"They want to be able to get out on these lands, enjoy undeveloped landscapes, see healthy populations of big game, be able to hunt the mule deer in the places that they've always hunted them," Stuble stressed. "And be able to pass these lands down to future generations instead of over to industry."
The leased lands include migration routes used by Baggs mule deer and Sublette pronghorn, and other big game migrations near Rawlins.
Stuble warned if the leases remain on the books now, they will constitute an irreversible commitment of land and resources, making it impossible to ensure the routes will be accessible to big game herds down the road.