Endangered Species Law & Policy

On November 30, 2023, the U.S. Fish and Wildlife Service (Service) published a final rule listing a distinct population segment (DPS) of the North American wolverine (Gulo gulo luscas) as a threatened species under the Endangered Species Act (ESA). The wolverine is a medium-sized carnivore found in Alaska, Canada and the western-northwestern United States. The current listing is limited to the DPS of wolverine occurring in the contiguous United States. In the Federal Register notice, the Service states that determining the wolverine’s exact population size is difficult due to the species’ large territory, however, the agency estimates there are fewer than 50 individual wolverines remaining in the contiguous United States. This is down from an estimated 318 wolverines that existed more than a decade ago.

The final rule comes in the wake of lawsuits filed by environmental organizations challenging the Service’s 2020 decision to withdraw its earlier listing proposals for the species. In response to the litigation, the Service agreed to voluntarily re-examine its prior withdrawal decision in light of new scientific information about the North American wolverine that had become available in recent years. As a result of this re-examination, the Service now finds that the contiguous United States DPS of the species meets the ESA’s definition of a threatened species.

ESA section 3 defines a threatened species as one that is “likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” As the primary threat to the species, the Service cites habitat loss stemming from the effects of climate change. The Service noted that wolverines prefer cold and snowy conditions and rely on persistent spring snow for denning and caching food, and studies predict that warmer temperatures and precipitation changes will directly impact snowpack loss across the species’ range.

In addition to the final listing rule, the Service issued an interim rule under section 4(d) of the ESA (4(d) rule) that prohibits “take” of the DPS. The prohibition on take forbids activities such as hunting, harming, harassing, or killing the wolverine, but it includes exceptions for certain activities resulting in take, such as purposeful take due to scientific research on wolverines, take incidental to forest management and wildfire reduction activities, and certain activities resulting in take incidental to legal trapping of species other than the wolverine. 

Both the final listing rule and the 4(d) rule will be effective January 2, 2024. However, the Service is accepting comments on the 4(d) rule with the intent to issue a revised rule by December 2024. The notice states that the Service will accept comments on the 4(d) rule until January 29, 2024.