Fisher

New York Status: Not listed

Federal Status: Not listed

Banner photo courtesy of R. Cook. 

Description

The fisher is a large, dark, long-haired member of the weasel family. Their stature is relatively low to the ground, with short legs, small ears, and a well-furred tail. The color of their fur varies from dark brown to nearly black. Females and juveniles usually have a more uniform color, and males will have a gray or grizzled appearance due to multicolored guard hairs around the neck, upper back and shoulders. Some individuals have a white or cream-colored chest, throat, and/or groin patch, often referred to as a blaze.

There is considerable evidence of dimorphism between the sexes, with males weighing between 7 and 15 pounds, and females between 3 and 7 pounds. Total lengths for males range from 35-47 inches, and females, 30-37 inches.

Fishers have large, wide feet and semi-retractable claws. This makes them well adapted for walking on snow, climbing trees, and grasping and killing prey. They are capable of rotating their hind feet nearly 180º, which allows for a headfirst descent from trees. As with all members of the weasel family, both sexes have anal scent glands which may be used to mark territories or attract potential mates.

Several common misconceptions are associated with the fisher. Firstly, it is often referred to as a fisher cat, even though it is not a cat nor is it closely related to cat species. Second, it is often assumed that fishers are named as such because they regularly catch and consume fish. They are actually called a fisher because early European settlers thought that they looked very similar to the European pole-cat, also known as a “fitch” or “fiche”. This may also be why the fisher is referred to as a fisher cat. Lastly, it is often reported that people hear a fisher “screaming” in the evening. Fisher have never actually been documented as having a screaming call, and are likely being confused with a number of other wildlife species that do, including red fox, gray fox, bobcat, coyote, great-horned owl, and barred owl. The only vocalization that fisher are known to make is a low volume guttural growl or chatter that can only be heard from a short distance away.

Fishers can sometimes be confused with other mustelid species found in New York, including mink, river otter, and American marten. Mink are similar in color to fisher, but are much smaller in size, almost always have a small white chin patch, and are generally found in close proximity to water. River otters are similar in size to fishers, but have a slightly lighter brown color with much shorter and sleeker fur, and are generally found in or close to water. American martens are much smaller than fishers, have a much lighter brown coloration, grayer head, and are only found in the Adirondack region.

Life History

Although fishers are often thought of as vicious killers, in reality they are opportunistic omnivores with a diverse diet that includes small mammals and birds, fruit, nuts, and more. They are the only known North American mammal that regularly preys on porcupines. In New York, diet analyses have found that small mammals (mice and voles) are the primary prey source, followed by fruit and then squirrels and chipmunks. Despite being commonly blamed for predation on turkeys, only one fisher out of over 500 had turkey parts in their stomach. See the figure below for a full breakdown of diet based on analysis of over 500 fisher stomachs that were submitted by trappers. 
 

Fishers breed in late winter in spring, with reproduction peaking in late March. They exhibit a reproductive strategy known as delayed implantation, which means that the fertilized eggs remain dormant for 10-11 months before implanting and developing. Females give birth to an average of 2-3 kits in March or April. Kits are born partially furred with closed eyes and ears, essentially helpless at birth. Weaning occurs within 8-10 weeks, and dispersal of young may occur by their fifth month, as interfamilial aggression begins by the onset of autumn.

Fishers use a variety of structures for year-round denning purposes such as the natural cavities found in older trees, hollow logs, cavities in rocky outcrops, brush piles, and underground burrows. Dens used for birthing of young are usually found in hollow sections of trees, high above the ground. Den holes are typically just large enough for the smaller female to squeeze through, and not large enough for males to get access to the kits.

Fishers lead a solitary lifestyle except for brief periods during the breeding season. They have been found to be active at any time during the day or night but are generally most active at dawn and dusk hours. Males generally have larger home ranges than females, and their territories seldom overlap that of other males, suggesting that they are territorial.

Fishers have few natural enemies, with coyotes and bobcats likely being the most important predators. Male fisher may also kill young kits if given the opportunity, a behavior called infanticide. Trapper harvest and automobile collisions likely account for the majority of fisher mortality across their range. A few species of tapeworm, intestinal roundworm, and flatworm have been identified in fisher, and their effects on health are minimal. Rabies and canine distemper have been described in fisher in New York State but are a minor source of mortality in the wild. Recent research on the impacts of second generation anti-coagulant rodenticides (ARs; typically referred to as rat poison) has indicated that fisher are exposed to a variety of different ARs across all parts of New York State and the Northeast, and this exposure may be causing population-level impacts to their populations.

Distribution and Habitat

Image Credit

Judy Foster

Found exclusively in North America, fishers inhabit a band of forested and semi-forested landscapes from coast to coast and prefer closed canopy forests of various ages. In the east, they range from Virginia north to Quebec and the maritime provinces of Canada. They use a variety of deciduous, coniferous, and mixed forest types, interspersed with shrub, scrub, and agriculture habitat types. Fishers are even able to thrive in suburban environments, including around and occasionally in larger cities like Albany, Rochester, and Buffalo. Historically, their numbers experienced a severe decline during the late 1800s and early 1900s due to over-exploitation and loss of forested habitat due to unregulated logging and the clearing of land for farms. Reintroduction programs have proven to be effective in restoring populations, along with regulation of trapping opportunities and the initiation of reforestation programs.

Fishers were extirpated from large portions of New York, with the exception of the Adirondack Mountains. In the 1970s, DEC re-introduced fishers to the Catskill Mountains. This reintroduction, combined with the regulation of trapping opportunities and reforestation efforts, have led to the fisher population expanding their range dramatically in New York. They are now considered common throughout upstate New York. Fishers do not currently exist on Long Island, nor are they documented in historical records to suggest they once occupied the area.

Status

Fishers are protected as a small game species in New York. Their population has grown over the past several decades, particularly in central and western New York. Once absent from this part of the State, they are now well-established in the Southern Tier, and populations are continuing to grow in the Lake Plains region. Harvest and observation trends all indicate that the fisher population is stable or growing across the state, but abundance of fisher varies considerably in different parts of the state, being the lowest in the Central Adirondacks.

Fisher Research

DEC has conducted a variety of fisher research projects in recent years. Starting in 2013, DEC, in partnership with the New York Cooperative Fish and Wildlife Research Unit (NYCFWRU), initiated a project to determine the relative abundance of fishers in Central and Western New York. This involved the deployment of trail cameras at over 600 sites during the winters of 2013-2015, and showed that fisher were fairly widespread throughout the region. A more detailed description of this project along with results can be found in the 2015 Fisher Management Plan (link available in the Fisher Management Plan section on this page). 
A conservative 6-day trapping season was opened in 2016 in parts of Central and Western New York, and a follow up camera survey very similar to the 2013-2015 survey was conducted from 2019-2021 to determine the impact of harvest on fisher populations. Results indicated that not only was harvest not resulting in a decline in the fisher population, but that the population actually increased since initial surveys in 2013-2015.

Fisher populations in the Adirondack region appeared to be not as robust as in Central and Western New York, leading to a shortening of the trapping season there in 2016. Similar camera survey work was conducted in the Adirondack and Tug Hill Plateau regions to look at fisher occupancy, and confirmed lower than ideal population levels in the Adirondacks. This work led to the start of a research project investigating declines in fisher populations in the Adirondacks, and comparing them to more robust populations in the nearby Tug Hill Plateau. The project was initiated in 2019, and consisted of live-trapping and deploying GPS collars on female fishers and VHF telemetry collars on male fishers. All fishers were monitored throughout the year, and mortalities investigated to determine different causes of mortality in each study area. Adult female fishers and their dens were also monitored during the spring denning period to determine the number of kits and their survival through that time, as well as female den attendance and activity. Results indicated that females in the Adirondacks had fewer young than the Tug Hill, and that trapping mortality was relatively low in the Adirondacks compared to the Tug Hill. A more comprehensive description of the project and its results can be found in the final report from SUNY-ESF (PDF).

More recent work in collaboration with the NYCFWRU has looked at fisher population trends across New York State in 2024. Results indicate that fisher populations in the Southern Zone of New York continues to grow at a slight rate, and that the population in the Adirondacks is stable, indicating that reductions in the trapping season there were warranted and are having a positive impact on the population.

Management

New York is one of 16 states with a regulated harvest season for fishers.  Harvest is closely monitored and every fisher taken must be reported and tagged by DEC personnel. This process allows biologists to collect harvest and demographic information (i.e., sex and age of the animal) and better understand the population. This information helps ensure sustainable populations that can be enjoyed by both consumptive and non-consumptive users in New York for generations to come. 

Fisher Management Plan

The New York State Fisher Management Plan (PDF) was completed in December 2015. The plan describes the goals, objectives, and strategies that will guide DEC's actions and decisions related to management of fisher populations in New York over the next ten years (2016-2025). The plan advances two primary goals for managing fisher populations in New York: (1) Maintain or enhance fisher populations in all areas of the state where suitable habitat exists; and (2) Provide for the sustainable use and enjoyment of fishers by the public.

The plan summarizes existing data on fisher populations and defines more specific objectives and strategies for Northern, Southeastern, and Central/Western New York including proposals to adjust current fisher trapping regulations and establish new trapping opportunities in some parts of the state.

See the Assessment of Public Comment on the Draft Fisher Management Plan (PDF) to review the public comments submitted regarding the plan and DEC's response.

Watchable Wildlife

When looking for wildlife in New York visit the Watchable Wildlife webpage for the best locations for finding your favorite mammal, bird, reptile or insect. New York State has millions of acres of State Parks, forests and wildlife management areas that are home to hundreds of wildlife species, and all are open to the public.

Remember when viewing wildlife:

• Don't feed the wildlife and leave wild baby animals where you find them.
• Keep quiet, move slowly and be patient. Allow time for animals to enter the area.

What to Watch for

Although their elusive nature makes sightings of fishers relatively uncommon, their sign can be seen in a wide variety of habitats across New York. They generally occupy a variety of forested or semi-forested habitats, so keep an eye out for tracks and scat in these areas.

• Tracks: Fisher have 5 clawed toes on both front and back feet, but typically only the front 4 larger toes and claws will register except in ideal track substrates. They have a C-shaped foot pad that typically registers on most tracks, and a smaller circular heel pad that may also register on occasion. Tracks are generally 2-3.5” wide and 2.5-4” long. Tracks are most often seen when snow is present, and the gait depends on the depth and consistency of the snow as well as the activity of the fisher. The most common pattern is a two-by-two lope, where all 4 feet leave a pair of touching circles with one being slightly forward of the other. These pairs of circles are made from the front feet touching the ground first, followed by the back feet taking their place as the front feet leave the ground. The distance between prints also depends on snow and activity, but is generally around 2-3ft. Fisher tracks may also appear as individual prints when they are moving slowly, foraging for food.
• Scat: Fisher scat is typically around a half inch in diameter or less and 2-5 inches long. Scats are cylindrical, occasionally bent into half, and typically are twisted with tapered ends, although every scat is different. Fishers often deposit scat on prominent objects along travel corridors, including rocks, logs, stumps, or mounds. Scats can come in a variety of colors and consist of a variety of partially digested food, especially berries, nuts, bones, and fur. Some fisher scats may also be composed almost entirely of porcupine hair and quills!