Fishers (Pekania pennanti) are one of the largest members of the weasel family in North America. Although males and females look similar, males can be twice as large in both length and weight. Their appearance varies seasonally, with their fur transitioning from mottled and lighter in the summer to denser and darker in the winter.
Physical Characteristics
Size: Males can be significantly larger than females.
Fur: Their fur undergoes a molting cycle, affecting color and density with the seasons.
Life History
Climbing Ability: Fishers are adept climbers, which expands their dietary options compared to other weasels like minks that share their habitat.
Historical Trapping: Their soft, dense fur led to extensive trapping since the 18th century, which reduced their population until bans were put in place in the 20th century.
Diet: Fishers are omnivores with a preference for snowshoe hares and are notably one of the few animals capable of successfully hunting porcupines. Contrary to their name, they rarely eat fish.
Habitat: They favor old-growth forests that provide ample cover from aerial predators such as hawks, eagles, and owls. Coarse woody debris helps them flush out prey and hide securely.
Social Structure: Fishers are solitary animals, with home ranges varying based on gender and season—females have smaller ranges in the summer, while males have larger ranges, particularly in the winter.
At Marsh-Billings-Rockefeller
Although the park contains ample second-growth old forests, fishers are rarely seen due to their crepuscular activity patterns. Protected areas like National Parks enable these animals to thrive. If you happen to encounter a fisher, maintain a safe distance and let the animal know you’re there.
