U.S. Fish & Wildlife Service

Sacramento Fish & Wildlife OfficeServing the people, conserving the fish, wildlife, and plants of California

A Unit Of The Pacific Southwest Region

Kids' Species Information




Candidate. This means that we plan to list the species as threatened or endangered. We have not done so yet because there are other species more in need of listing.


Fishers are related to weasels. They have long bodies with short legs.

Fishers are bigger than weasels. Adults are from 90 to 120 centimeters long. (About 2.5 to 4 feet). Males weigh 3 to 6 kilograms. (About 7 to 13 pounds) Females weigh 1.5 to 2.5 kilograms (About 3 to 5.5 pounds).

The fisher's head is broad and flat with a sharp, pronounced muzzle. Its eyes face forward and ears are broad, rounded and low. Its tail is long and bushy.

Fur color varies from light to dark brown. The face, neck and shoulders may be a lighter gray. Often there are white patches on the chest and underside.

Fishers have five toes and retractable claws. Their feet are large with a pad on each toe and a group of four central pads.

Fishers can rotate their hind paws almost 180 degrees. This allows them to come down trees head first like a squirrel.


Fast, agile and adept at climbing trees, fishers eat any prey they can catch and overpower, including squirrels, hares, mice and birds. The name "fisher" is misleading. Fishers do not actually catch fish!


Photo: Mark Higley, Hoopa Tribal Forestry


Old forests with lots of prey and protection from predators. Fishers use habitat with high canopy closure, large trees and snags, large woody debris, large hardwoods and multiple canopy layers.


Fishers can live up to ten years in the wild.


The breeding season for is from late February to until mid-April. Birth occurs nearly 1 year after copulation. This is because embryos are not implanted for about 10 months. Litter sizes generally range from one to four. These are raised by the mother.


Hawks, foxes, lynx, bobcats.


The conifer and mixed forests of Canada and the northern United States. There is one population in northwestern California and another in the southern Sierra Nevada Mountains.


The West Coast population of the Pacific fisher is endangered by habitat loss and fragmentation, small population sizes and isolation, and human-caused mortality from incidental trapping and vehicle collisions.


You probably will never see one of these shy, secretive animals. But you can explore the forests where they live. These include Redwood and Yosemite National Parks and various National Forests (See forest list.)


Hoopa Indian Tribe leads in fisher conservation. (209 KB PDF)

Words to Learn

Biologists call fishers Martes pennanti. Scientific names are in Latin or Greek.

You may find the name Pacific fisher. Some researchers divide the species into three subspecies, including one named Martes pennanti pacifica or Pacific fisher. We do not recognize this distinction.

Fishers are in the Mustelidae family. This family includes weasels, polecats, minks, martens, fishers, wolverines, otters, badgers and others.

Canopy: The "roof" of the forest formed by the crowns of the trees.

Please read our children's privacy statement.

Last updated: November 29, 2017