A formal petition to the US. Fish & Wildlife Service was submitted in September 2013 to seek protection for the imperiled Northern Rockies Fisher as threatened or endangered under the Endangered Species Act. The petition also requested that critical habitat be designated, in conjunction with a finding that the fisher, indeed, warrants federal protection. Trapping, predation, disease, road building, logging and loss of habitat, particularly old-growth forests, have led to the sharp decline of the formidable predator.
Once prevalent in eastern British Columbia, southwest Alberta and throughout eastern Washington, Idaho, Montana, northwest Wyoming and north-central Utah, scientists believe the medium-sized, forest-dwelling carnivore now only survives in small-density populations straddling the Idaho/Montana border.
The US Fish & Wildlife Service classified the species as a Distinct Population Segment in 2011 due primarily to genetic characteristics that differentiates the Northern Rockies Fisher from all others in the U.S. It is also believed that fisher found in north-central Idaho are genetically unique, as they may have descended from fisher populations that have been in the area for generations, rather than, as previously believed, from fisher reintroduced to north-central Idaho in the 1960s.
It is uncertain how many fishers survive in the vicinity of the Idaho/Montana border, but the best-available science suggests that the largest populations make their home in the Clearwater Basin.
When the U.S. Fish & Wildlife Service failed to respond to the 2013 petition within the legal time-frame, groups filed a Notice of Intent in 2014 to sue the agency. The U.S. Fish & Wildlife Service finally responded in 2016, and issued a finding that Northern Rockies Fisher may warrant protection under the Endangered Species Act. In September 2017, the US Fish & Wildlife Service announced that the species does not warrant listing as threatened or endangered under the Endangered Species Act.