Just a little something I dug up on the little Bugger
Geographic Range
Nearctic: Fishers are found only in North America, from the Sierra Nevada of California to the Appalachians of West Virginia. They range along the Sierra Nevada to it's southernmost extent and south along the Appalachian mountain chain. They do not occur in the prairie or southern regions of the United States. Populations have declined in the southern parts of their range in recent history.
^ Physical Characteristics
Mass: 2000 to 5000 g.
Males average larger than females, with a body length of 900 to 1200 mm in males and 750 to 950 mm in females. Tail length is between 370 and 410 mm in males and 310 to 360 mm in females. Mass is from 3500 to 5000 grams in males and from 2000 to 2500 grams in females. Their coats range from medium to dark brown, with gold to silver hoariness on their head and shoulders, black legs and tail. They may also have a cream chest patch of variable size and shape. Fur color and pattern varies among individuals, sexes and seasons. Fishers have five toes on their feet, and their claws are retractable.
^ Natural History
^ Food Habits
Fishers are predators, and most of their prey are herbivores. Fishers eat mice, porcupines, squirrels, snowshoe hares, birds, and shrews, and sometimes, other carnivores. They may also feed on fruits and berries, such as beechnuts and apples.
They have also been seen to eat white-tailed deer, though they are most likely scavenging a deer carcass.
Fishers are in competition for food with foxes, bobcats, lynxes, coyotes, wolverines, American martens and weasels. Fishers and American martens are the only medium-sized predators agile in trees that also possess the ability to elongate themselves to seek prey in holes in the ground, hollow trees and other small areas. Fishers are solitary hunters, and seek prey that is their own size or smaller, although they are capable of taking on prey larger than themselves.
^ Reproduction
The breeding season is late winter and early spring. Gestation lasts almost a full year, 11-12 months. The average number of young in a litter is 1-5 (young). Healthy females first breed at age 1, produce their first litter at age 2, and probably breed every year after that. So the female essentially spends almost all of her adult life in a state of pregnancy or lactation. It is not known whether mating is mongamous, polygynous or polyandrous. Most dens in which young fishers are raised are high up in hollow trees, and females may choose to move their young up to several times if the litter is at all disturbed.
There is some sexual dimorphism in body size--both weight and length.
^ Behavior
Fishers are agile and speedy tree climbers. Theyare quite solitary; there is little evidence that they ever travel together, except possibly during the mating season. There has been some observed aggression between males, which supports the notion that they are solitary. Home range size varies from 12-30 kilometers in diameter and 100-800 kilometers in area. Home ranges also seem to overlap extensively. Communication between fishers occurs through scent marking.
Fishers use "resting sites", such as logs, hollow trees, stumps, holes in the ground, brush piles and nests of branches, during all times of the year. Ground burrows are most commonly used in the winter, and tree nests are used all year, but mainly in the spring and fall. During the winter, fishers use snow dens, which are burrows under the snow with long and narrow tunnels leading to them.
Fishers are active during the day and night and may be agile swimmers.
^ Habitat
Fishers prefer continous forests, but they are also found in conifer and hardwood forests. They prefer habitats with high canopy closure. They also prefer habitats with many hollow trees for dens, and they are usually found in forested areas with continous overhead cover. Trees typically found in fisher habitats include, among others, spruce, fir, white cedar and some hardwoods. Also, as would be expected, their habitat preference reflects that of their favored prey species.
Biomes: taiga, temperate forest & rainforest, temperate grassland, mountains
^ Economic Importance for Humans
^ Positive
Fishers are trapped and killed for their pelts. Trapping, in the past, had a significant effect on fisher populations, but the problem is not as severe now. Fishers hunt porcupines, and can effectively control porcupine populations (porcupines are known to damage timber crops by debarking and killing trees).
^ Negative
In recent years fisher populations in some areas, particularly southern Ontario and New York, have been recovering. In these areas they may be becoming habituated to human presence and venturing into suburban areas. There have been numerous reports of fisher attacks on domestic animals and even children. It is important to recognize that fishers are simply trying to find food and protect themselves. It is important to restrict access to garbage, pet foods, pets, and domestic fowl. When startled, fishers may react aggressively to the perceived threat. Diseased individuals may react unpredictably.
^ Conservation
Status:
IUCN: No special status
U.S. ESA: No special status
CITES: No special status
Logging of forests greatly impacts fishers and fisher populations by destroying their preferred habitat--continous or nearly continous coniferous forests. Fishers are important predators in forest ecosystems of northern North America. Fisher populations seem to do well in appropriate, undisturbed habitat.
Zoos have had a hard time breeding fishers in captivity, but there has been some success. Because there are numerous thriving and healthy fisher populations, there has been little pressure or initiative to develop fisher breeding or maintaining programs in captivity.
In some areas of North America, such as Michigan, Ontario, New York, and some areas of New England, fisher populations seem to have rebounded in recent years.
Fisher populations in the southern Sierra Nevada have been proposed as candidates for protection under the Endangered Species Act.
^ Other Comments
Fishers are generally thought of as secretive and rarely observed. This may be changing in parts of their range as populations re-expand and become habituated to human presence.
Their longevity in the wild is unknown, but they have lived for 10+ years in zoos. Fishers have a low incidence of diseases as well.
^ References
Macdonald, David. (editor) The Enclopedia of Mammals. Facts on File Publications, NY. 1984
Powell, Roger A. The FIsher: Life History, Ecology, and Behavior. University of Minnesota Press, MN. 1993.
Johnson and Todd. Fisher, Behavior in Proximity to Human Activity. Canadian Field Naturalist 99 (3) 1985.
Arthur, Krohn and Gilbert. Habitat Use and Diet of Fishers. Journal of Wildlife Management 53 (3) 1989.
