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The west coast population of the fisher was accorded federal
candidate status in April 2004.
The state of Oregon lists the fisher as a sensitive
species.
Currently, the USFWS is reviewing the status of the fisher throughout the range of the west coast distinct population segment, including an analysis of whether the west coast distinct population segment warrants listing under the Endangered Species Act. At the conclusion of the status review, we will issue either a not-warranted finding or proposed rules for listing the species and critical habitat.
In Oregon, the west coast distinct population includes the Oregon Cascades west to the coast. An information gathering period regarding the status of the fisher is now open and we encourage interested parties to provide information regarding the status of, and any potential threats to, the west coast distinct population. We will take information until May 3, 2013. Federal Register Notice>
Historic
Status and Current Trends
Fishers, found only in North America, occur in the northern coniferous
and the mixed forests of Canada and the northern United States.
Their range extends from the mountainous areas in the southern
Yukon and Labrador Provinces southward to central California and
Wyoming, the Great Lakes and Appalachian regions, and New England.
In Oregon, fishers occurred historically throughout the Coastal
and Cascade mountains. Currently, the range of the fisher is severely
reduced. Despite extensive surveys conducted in forested regions
of Oregon, records dating from 1954 to 2001 show that the remaining
populations of fishers are restricted to two separate and genetically
isolated populations in southwestern Oregon; one in the northern
Siskiyou Mountains and one in the southern Cascade Range. The
population in the southern Cascades descended from reintroduced
fishers that were translocated to Oregon from British Columbia
and Minnesota.
Description
and Life History
The fisher, a member of the weasel family (Mustelidae), has
a long body, short legs and a long, bushy tail. The head
is broad and flat with a sharp, pronounced muzzle. The ears are
broad, rounded, and low. Fur color varies from light brown to
dark blackish brown, although the face, neck, and shoulders may
have a lighter grizzled gray appearance. Often there are irregular
white patches on the chest and underside. Fur length ranges from
30 millimeters (about 1 inch) on the stomach and chest to 70 millimeters
(about 2.75 inches) on the back. Adults range in length from 90
to 120 centimeters (about 2.5 to 4 feet). Males weigh 3 to 6 kilograms
(about 7 to 13 pounds); females weight 1.5 to 2.5 kilograms (about
3 to 5.5 pounds). Large feet, with 5 toes on all 4 feet and retractable
claws, enable fishers to rotate their hind paws almost 180 degrees,
allowing them to run down trees head first like a squirrel. Central
pads on the hind paws have circular patches of coarse hair which
are associated with plantar glands. These glands produce a distinctive
odor believed to be used for communication during reproduction.
It is estimated that fishers live up to 10 years. They are solitary
animals except during the breeding season (late February through
April).
Fishers are opportunistic predators that hunt exclusively in
forested habitats where prey is abundant and vulnerable to capture.
Their diverse diet includes birds, porcupines, snowshoe hare,
squirrels, mice, shrews, voles, reptiles, insects, carrion, vegetation,
and fruit. Their name is misleading since fishers do not actually
catch fish. The name may have come from early European settlers
who noted the fisher's similarity to the European polecat which
was variously known as a fitchet or fitchew.
Habitat
Fishers are associated with forests having moderate to dense forest canopy and complex structure (for example, large amounts of coarse down wood, moderate shrub cover, dead trees and trees with decay elements, and a component of hardwood trees). The physical structure of this type of forest provides the fisher with reduced vulnerability to predation and an abundance of prey. The distribution of the fisher is likely limited by elevation and snow depth.
Reasons for Decline
The west coast population of the fisher is at risk mainly
because of loss and fragmentation of habitat due to timber harvest,
roads, urban development, recreation, and wildfires. Other threats
include small population sizes and isolation, predation, and human-caused
mortality from vehicle collisions, poaching, and incidental capture
and injury.
Conservation Measures
Between 2008 and 2010, the National Park Service reintroduced nearly 100 fishers into Olympic National Park from populations in nearby British Columbia. Fishers are also being reintroduced onto private timber company lands in the northern Sierra Nevada range of California in an effort to reestablish fisher into their historic range.
We are encouraging state and federal agencies who are proposing activities within the historic range of the fisher to give consideration to the fisher during the environmental planning process, especially activities which alter or destroy mature and old growth forests, as well as other biologically complex forests.
References and Links
Aubry, K. B., Lewis, J. C. 2003. Extirpation and reintroduction
of the fisher (Martes pennanti) in Oregon: implications for their
conservation in the Pacific states. Biological
Conservation 114 (1):79-90.
Powell, R.A. and W.J. Zielinski. 1994. Fisher. In: Ruggiero,
L. F, Aubry, K B, Buskirk, SW, Lyon L.J., and Zielinski, W. J.
eds. American marten, fisher, lynx, and wolverine. Gen. Tech.
Rep. RM-254. Fort Collins, CO. Rocky Mountain Forest and Range
Experiment Station, Forest Service, U.S. Department of Agriculture;
184 p.
U.S. Fish and Wildlife Service. 1996. Endangered and threatened
wildlife and plants; 90-day finding for a petition of list the
fisher in the western United States as threatened. FR
61:8016-8018.
U.S. Fish and Wildlife Service. 2003. Endangered and threatened
wildlife and plants; 90- day finding for a petition to list a
distinct population segment of the fisher in its west coast range
as endangered and to designate critical habitat. FR
68:41169-41174
U.S. Fish and Wildlife Service. 2004. Endangered and Threatened
Wildlife and Plants; 12-month
Finding for a Petition to List the
West Coast Distinct Population Segment of the Fisher (Martes
pennanti).
Portland,
Washington Department of Fish and Wildlife Final
Report 1998.
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