Wolverines now listed as a threatened species

The U.S. Fish and Wildlife Service has determined that shorter winters and springs with reduced high-elevation snowpacks brought on by climate change are degrading habitat for wolverines and will list them as a threatened species across the Lower 48 states.

The agency will develop a map of habitat deemed critical for the elusive species known for its ferocity. In the interim, it will establish temporary rules forbidding killing wolverines and the possession, sale, import or export of the animals. There is an exception for the wolverines taken during the course of scientific studies, as the result of forest management projects designed to reduce wildfires, as well as wolverines taken during legal trapping seasons targeting other species so long as those seasons include rules designed to minimize trapping of wolverines.

Wildlife officials believe there are 250 to 300 wolverines in the northern tier of the contiguous United States. That includes animals in Idaho, Montana, Washington and Oregon.

Wolverines require healthy snowpacks that persist late into the spring and don’t like development or persistent human presence. Between February and May, females den and raise kits in the snowfields that cling to mountain peaks.

In new research, scientists have documented those sites are disappearing and will continue to do so as the climate warms and spring snowmelt accelerates. Fragmentation of habitat has already led to a reduction in wolverine genetic diversity, according to the agency.

The agency’s view of wolverines and the degree of protection the elusive animals require has wavered over the past decade: It has issued decisions both in favor of and against listing them as threatened under the Endangered Species Act. Most recently the agency decided not to protect the animals in 2020. That prompted a lawsuit from a coalition of environmental groups and was followed by the agency taking another look at the species and the challenges it faces.

“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.”

New research also shows winter recreation can negatively affect wolverines and that areas used by both the animals and skiers, snowshoers and snowmobilers will increasingly overlap as snow-covered areas decline.

The agency found trapping, including the increasingly long and liberal wolf-trapping seasons in Idaho and Montana, has minimally affected wolverines.

The listing decision and instructions to submit comments on the interim rules are available at bit.ly/3T4r9nK. The comment period is open until Jan. 29.

Barker may be contacted at ebarker@lmtribune.com or at (208) 848-2273. Follow him on Twitter @ezebarker.