The fisher is a mammal belonging to the Mustelidae family, which includes otters, minks, and weasels. Known scientifically as Pekania pennanti, the fisher has a confusingly aquatic-sounding name but is primarily a forest-dwelling predator. Fishers are capable of swimming strongly when necessary, though they are not considered aquatic animals. Their habitat and hunting strategies focus overwhelmingly on terrestrial and arboreal environments.
What Exactly Is a Fisher?
The fisher is a medium-sized carnivore found exclusively in the forests of North America. Its body shape is characteristic of the weasel family, featuring a long, slender torso, short legs, and a dark brown to black coat. These physical traits allow them to be agile ground hunters and skilled climbers, often utilizing dense forest canopy.
Males are notably larger than females, weighing between 4 and 6 kilograms and measuring up to 120 centimeters in total length. Females are smaller, typically weighing 2 to 3 kilograms. They are solitary animals that prefer large, continuous blocks of forest habitat, where they hunt a variety of small and mid-sized prey.
Fisher Swimming Ability and Behavior
Fishers are strong and capable swimmers, though they are not semi-aquatic like their close relatives, the river otters. This ability is situational, used for functional purposes rather than being a primary mode of travel or hunting. They may enter the water to cross a stream or river in their path or to escape a larger predator.
A fisher may pursue prey into the water, demonstrating their versatility and opportunistic nature as a hunter. Their body shape, built for flexibility on land, allows them to paddle effectively in water. Despite this ability, the vast majority of their movement, foraging, and resting activities occur on the forest floor and within tree cavities.
The Origin of the Name
The name “fisher” is a historical inaccuracy that has persisted, leading to confusion about the animal’s diet and habitat. The most accepted explanation is that the name is a corruption of an earlier term used by European settlers. This term was likely “fitch” or “fiche,” which were names for the European polecat or its pelt, an animal the fisher resembles.
Early Dutch colonists may have used the equivalent terms fisse or visse, which over time became anglicized to “fisher.” This etymological shift is the primary reason for the misconception that the animal hunts fish, a food source it rarely consumes. Fishers are instead known for preying on snowshoe hares, small rodents, and birds. They are also one of the few predators that successfully hunt porcupines.