PHOTO BY KAREN BOSSICK

The U.S. Fish and Wildlife Service announced Wednesday that it will protect the wolverine population in the lower 48 states as threatened under the Endangered Species Act, a decision that will provide this rare wilderness species with new legal protections and programs for recovery.  

The decision represents the culmination of a campaign by conservationists over decades that required six rounds of successful litigation to secure federal protections. Most recently, conservation groups succeeded in 2022 in persuading a federal judge to vacate a 2020 decision by the service denying ESA protections for wolverines in the lower 48 states. That victory sent the agency back to the drawing board to reconsider its determination and set the stage for today’s listing decision. 

“This long-awaited decision gives the wolverine a fighting chance at survival,” said Timothy Preso, an Earthjustice attorney who represented conservation groups in the long-running legal campaign to protect the wolverine. “There is now hope for this icon of our remaining wilderness.” 

Conservation groups originally petitioned to list the wolverine as threatened under the act in 1994 and again in 2000. For decades, the service repeatedly delayed and obstructed the proposed wolverine listing, forcing wolverine advocates to turn to the courts for enforcement of the act. Earthjustice and the groups it represents won every case they filed on behalf of the wolverine, either through judicial rulings in their favor or through favorable settlement agreements. 

“The science is clear: snowpack-dependent species like the wolverine are facing an increasingly uncertain future under a warming climate,” said Michael Saul, Defenders of Wildlife Rockies and plains program director. “The protections that come with Endangered Species Act listing increase the chance that our children will continue to share the mountains with these elusive and fascinating carnivores.”

The wolverine, the largest terrestrial member of the weasel family, is threatened with massive habitat loss due to climate change. Wolverines depend on areas with deep snow through late spring. Pregnant females dig their dens into this snowpack to birth and raise their young. Scientists estimate that no more than 300 wolverines remain in the lower 48 states. 

Wolverines once roamed across the northern tier of the United States and as far south as New Mexico in the Rockies and Southern California in the Sierra Nevada range. After more than a century of trapping and habitat loss, only a few hundred remain in the lower 48 today, existing only as small, fragmented populations in Idaho, Montana, Washington, Wyoming, and northeast Oregon.

They have occasionally been spotted in the greater Sun Valley area. 

Wolverine populations are also at risk from traps, human disturbance, habitat fragmentation, and extremely low population numbers resulting in low genetic diversity.

“Biologists estimate a loss of more than 40% of suitable wolverine habitat in Idaho by 2060 if we fail to act,” said Jeff Abrams, wildlife program associate for the Idaho Conservation League. “This decision allows us to move forward on recovery actions to prevent such extensive loss of wolverine habitat and recover wolverine populations.”