Center for Biological Diversity

For Immediate Release, September 12, 2018

Contact: Randi Spivak, (310) 779-4894,

Analysis: Zinke Offering 1.2 Million Acres of Wyoming Pronghorn, Mule Deer Habitat to Oil, Gas Industry

WASHINGTON— Interior Secretary Ryan Zinke will offer more than 1.2 million acres of pronghorn and mule deer winter habitat and migration corridors in Wyoming for oil and gas extraction in 2018, according to a new analysis by the Center for Biological Diversity.

Today’s analysis is based on available state and federal records of mule deer and pronghorn habitat, along with the areas planned for quarterly oil and gas lease sales in Wyoming.

“Zinke’s plan would let big oil companies choke off vital migration routes and winter range for pronghorn and mule deer,” said Randi Spivak, the Center’s public lands director. “This analysis should be a wake-up call for anyone fooled by Zinke’s claim to care about wildlife. His push for massive new frack fields will drive these magnificent animals and their ancient migratory ways to the brink.”

Zinke’s fossil fuel leases on public land come despite his February 2018 secretarial order intended to “improve habitat quality and western big game winter range and migration corridors for antelope, elk, and mule deer.” The net result of the Interior Department’s 2018 leases will be an increase in fracking, drilling, fragmentation and industrialization of this important wildlife habitat.

The Center sent a letter to Zinke, calling on him to halt all oil and gas leasing in critical mule deer and pronghorn habitat, including winter range and migratory corridors in Wyoming. These protections are needed to preserve some of the largest herds in the West and the last great wildlife migrations in Wyoming.

The Bureau of Land Management and fossil fuel companies have long claimed that oil and gas development causes only short-term harm to big game, and that the animals adapt to the area once drilling activities are complete. But research released in April 2017 confirms that is not the case with mule deer.

This 17-year study in the Pinedale Anticline gas field in Wyoming’s Upper Green River Basin found mule deer moved farther away from the well pads even when drilling was winding down and remediation was in progress.Mule deer numbers declined by 36 percent to 42 percent over the 15-year development period, more than double the overall 16 percent decline in the region.

The study found that these declines occurred despite extensive mitigation efforts such as directional drilling, pipelines to reduce truck traffic and offsite habitat protection.  

“The science is clear, and the next step is obvious,” Spivak said. “Zinke needs to honor his pledge to protect big-game habitat. The BLM should withdraw vital mule deer and pronghorn habitat in Wyoming from consideration for oil and gas leasing and other industrial activities.”

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.6 million members and online activists dedicated to the protection of endangered species and wild places.

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