Two kids running in the snow. We all need nature—and nature needs you. Together, we can protect the wildlife and wild lands of Massachusetts for generations to come. Make a tax-deductible donation today.
Two kids running in the snow. We all need nature—and nature needs you. Together, we can protect the wildlife and wild lands of Massachusetts for generations to come. Make a tax-deductible donation today.
A fisher looks over its shoulder by the edge of water.

Groton, MA © Scott Eggimann

Fishers

Despite commonly being called "fisher cats," a Fisher is not a cat, nor do they catch fish. Fishers are the second-largest member of the weasel family found in Massachusetts, after the North American River Otter. 

How to Identify a Fisher 

As with other weasels, Fishers have long, slender bodies and a low profile when moving along the ground. Their coat is dark brown, dense, and glossy. Males are typically larger than females, measuring about 3 feet and weighing up to 20 pounds.  

The tapering tail of a fisher can account for one-third (12–16 inches) of its length. Their legs are short and stout. Fishers have partially retractable claws that make them agile and speedy tree climbers, capable of jumping up to 7 feet between trees. 

A fisher with a long tail standing on a dead log.
© Paul Malenfant

Fisher Behavior 

Secretive and elusive by nature, Fishers like to keep their distance from humans. They are solitary creatures, except during their brief mating season in late winter, and are active both night and day throughout the year. Some videos and audio recordings online show loud, unearthly "screaming" sound that people have attributed to Fishers, however, the nighttime vocalist in these videos is nearly always a Red Fox. 

What Do Fishers Eat? 

They use scent to locate prey, and successful hunts require silence and stealth. Although they will consume berries and fruit, Fishers are mainly carnivores and eat rabbits, snowshoe hares, squirrels, raccoons, mice, reptiles, amphibians, insects, carrion (dead or decaying animal flesh), and occasionally outdoor cats.  

Fishers are one of the few mammals that prey on porcupines. Porcupines are difficult to kill, but a dead porcupine can provide many days of food for a Fisher and is worth the effort. While on the ground, the Fisher continually attacks the only vulnerable portions of the porcupine’s body—the face and underbelly. When facial wounds have weakened the porcupine, the Fisher goes in for the kill. To avoid the quills, Fishers eat their prey starting at the head, neck, or underbelly. 

© Barbara Batchelder

When do Fishers Breed? 

Breeding occurs in March or April when females are 1-2 years old. After a delayed implantation period of 10 or 11 months, the blastocyst (the earliest stage of the embryo) is implanted in the womb, possibly stimulated by changing day length. Once that happens, the embryo develops in only six weeks. 

Female fishers look for tree cavities with an opening large enough for the mother to enter but small enough to prevent predators that may harm her kits. And since females can mate again within just a few days after giving birth, mothers must guard the den against male Fishers looking for a mate. Male Fishers do not help raise their young. 

Kits are born in March with litters of 1–6 individuals. Born blind and with very little fur, the helpless kits depend on their mother for the next few months. Young Fishers begin to capture their own prey around four months and disperse by the time they are five months old. 

Where do Fishers Live? 

Fishers live in southern Canada, New England, and New York, and scattered locations in Pennsylvania, West Virginia, and Virginia. They could potentially be found in practically every community in Massachusetts. They are forest-dwelling mammals that use various forest habitats and avoid open areas like fields and roads. 

Fisher resting in a tree © Joshua Goddard
Fisher © Joshua Goddard

The average home range of a Fisher is around 15 square miles in size. For males, that area is typically between 6–32 square miles. A female's home range tends to be smaller, averaging 5 square miles, and is more stable across the seasons than a male's range. Since they prefer to avoid traveling in large, open areas, Fishers opt for mixed forest habitats with heavy canopy cover. They can travel up to 18 miles in a single 24-hour period. 

Threats Facing Fishers 

Fishers were forced out of southern New England by the 19th century. This was primarily because, during the 1700s and 1800s, loggers and farmers cleared most of the forests in the northeast and unregulated trapping was rampant. However, in the late 1800s, people began abandoning their farms for other prospects. Over the next several decades, the forests gradually returned to the landscape and the Fishers followed. 

Intentional reintroduction efforts also helped Fisher populations rebound. In the 1950s, with permission from each state, logging companies reintroduced Fishers into northern New England to control porcupines. At the time, porcupines were decimating seedlings planted by the timber companies to reestablish trees in logged areas—and Fishers were the only species that deliberately target porcupines as prey. 

Today, Fisher habitats are under threat again by climate change. Without healthy, un-fragmented forests, Massachusetts Fisher populations could decrease again. Other threats to Fishers are mammalian-contracted diseases, such as rabies.  

A fisher with just its head and one paw sticking out from a hole in a tree. The paw has sharp long claws.
© Jon Kaufman

How Mass Audubon Helps Fishers 

Fishers are required to create an abundant and diverse forest ecosystem. Mass Audubon is helping Fishers by protecting their habitats, building resilient landscapes, and creating a safe, continuous ecosystem where they can thrive. You can help us conserve and protect Fishers by becoming a member today.  

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