Fishers are the largest arboreal or tree-dwelling member of the weasel family. They are most closely related to wolverines and martens. Unlike the latter two species, fishers have relatively small feet and prefer lower elevations that do not have deep snow. Fishers are dependent on old growth forests or habitat and complex forest structure.
Fisher are the only animal in North America to concentrate on hunting porcupines. Cougars are the only other species that will prey on porcupines, although that is not there preferred prey or specialty. Fishers are very fast, are able to prod under porcupines and can tire the porcupine before attacking its face.
Most of the best fisher habitat in the Clearwater is unfortunately roaded. There are some low-elevation roadless portions of the forest in the N. Fork Clearwater and Lochsa drainage. There is good fisher habitat in the Selway-Bitterroot Wilderness, too, but it seems the best core habitat is in the Lochsa.
Fishers found in the Clearwater have genetic material that makes them unique. These fishers still have approx. half their original genetic material from the fishers that were originally found in the Clearwater. Until recently, it was thought that the only fishers in the western part of lower 48 were from re-introductions in the 50′s and 60′s. Fishers were reintroduced around that time to protect trees from porcupines (think logging industry).
The best habitat for fishers in the entire West is in the Clearwater Basin. Clearing of forests, habitat destruction, fires and over-trapping has resulted in its overall decline or extirpation. Climate change could increase the frequency of forest fires in its range, removing the older, cavity-bearing trees it needs for denning. Currently, the fisher is not protected as an endangered or threatened species, despite its population dipping to a staggeringly low 500 individuals in Idaho and Montana.
The US Fish & Wildlife Service is now taking comments to decide if the Northern Rockies Fisher warrants protection under the Endangered Species Act.
Click here to submit a public comment by February 13.