Implementation Plan for Reintroducing Fishers to the Cascade Mountain Range in Washington


Published: November 4, 2013

Pages: 37

Author(s): Jeffrey C. Lewis

Executive Summary

The goal of this implementation plan is to outline a successful approach for reestablishing fisher populations in the Cascades Recovery Area, as outlined in the Fisher Recovery Plan for Washington. With successful reintroductions and population growth, fishers released in the southwestern and northwestern Cascades will become connected, self-sustaining meta-populations. This outcome would allow for a down-listing of fishers from endangered to sensitive status in the state and it would represent a significant improvement in fisher conservation status for Washington and for the fisher’s west coast population.

The fisher (Pekania pennanti) is a mid-sized carnivore in the weasel family (Mustelide) that occurs only in the temperate and boreal forests of North America. Because of their valuable pelt, fishers were trapped intensively throughout much of their range. Over-exploitation of fisher populations in the late 1800s and early 1900s caused a widespread contraction of the fisher range in North America and the loss of fishers from most of the U.S. and much of southern Canada. Population declines prompted the closure of fisher trapping seasons in many states in the early 1900s, however these season closures came too late to protect many fisher populations. Beginning in the 1940s, wildlife managers and resource managers began reintroducing fisher populations to restore a valuable furbearer, a valuable predator of porcupines, and a missing member of the carnivore community. The fisher is among the most successfully translocated carnivore species, owing to the fact that most fisher populations were extirpated as a result of over-exploitation rather than loss of habitat.

Fishers historically occurred throughout the forested areas of Washington State including most of western Washington, the Selkirk Mountains of northeastern Washington, and the Blue Mountains of southeastern Washington. A decline in fisher harvests in the early 1900s prompted the newly established Washington Department of Game to close the fisher trapping season in 1934 to protect fishers and promote recovery. Despite this closure, fishers did not recover within the state. Carnivore surveys conducted throughout the state in the 1990s detected the presence of many carnivore species, however no fishers were detected within their historical range in the state.

A fisher status review completed in 1998 indicated that a reintroduction was the only way to recover fishers in the state. Following the status assessment the Washington Fish and Wildlife Commission included the fisher on the list of state endangered species in 1998. A feasibility assessment by Washington Department of Fish and Wildlife (WDFW) in 2004 concluded that fishers could be successfully reintroduced on the Olympic Peninsula, the southwestern Cascades, and the northwestern Cascades. The assessment indicated that the factors that contributed to fisher extirpation no longer exist (fisher trapping, incidental capture, predator and pest control campaigns) or are greatly diminished (habitat loss and fragmentation). In 2006, WDFW developed a recovery plan for the fisher. The recovery plan identified three recovery areas (Olympic, Cascade and Selkirk), and outlined recovery tasks that included the reintroduction of fishers in the Olympic and Cascades Recovery Areas. Reestablishment of fishers in these two recovery areas would be required to down-list the fisher from state endangered to state sensitive status.

The translocation of 90 British Columbia fishers to the Olympic Peninsula from 2008 to 2010 was the first step toward fisher recovery. To take the next step toward recovery, WDFW, the National Park Service and other partners are proposing to reintroduce approximately 160 fishers from British Columbia to the Cascades Recovery Area in two stages. The first stage of the project will be the reintroduction of .80 fishers to a reintroduction area located in the southwestern portion of the Cascades Recovery Area over a 2-3 year period, beginning in the fall 2014. Each fisher will be equipped with a radio-transmitter and we would monitor released fishers over a 3-4 year period beginning in the fall of 2014. The second stage of the project will be the reintroduction of .80 fishers to a reintroduction area located in the northwestern portion of the Cascades Recovery Area over a 2-3 year period, which could begin the year after fisher releases were completed in the southwestern Cascades. Monitoring efforts in the second stage would follow the approaches outlined for the first stage.

The monitoring program is designed to allow biologists to adaptively manage the reintroduction to increase the likelihood of success, and to determine if the reintroduction has succeeded at reestablishing a self-sustaining population. Movements, survival, and home range establishment of fishers will be monitored immediately upon release. Confirming reproduction will become a focus of the monitoring program during the denning season (March to June). The reintroduction will be considered initially successful if there is evidence that a reproductive population has become established within the first 3-4 years of a reintroduction. The long-term success of the reintroduction will be indicated by the persistence of a self-sustaining population as determined by monitoring efforts conducted between years 5 and 10 after the initial releases.

This plan outlines the process and considerations for 1) coordinating efforts with the Province of British Columbia for obtaining fishers, 2) capturing, transporting, housing and husbandry of fishers, 3) veterinary care and the preparation of fishers for reintroduction, 4) the process for crossing the US-Canada border with fishers, and 5) releasing and monitoring fishers. The plan provides a brief outline of how monitoring efforts could be expanded into formal research of the biology and ecological relationships of fishers in the Washington Cascades ecosystem. It also outlines a strategy for public outreach about fisher reintroductions in the Cascades Recovery Area and presents a timeline for project activities.

Cost of a reintroduction in each area is estimated at $550,000 if completed in 3 years, or at $750,000 if completed in 4 years; consequently, the total cost for reintroductions in both project areas is estimated as $1,100,000-1,500,000 over 6-8 years. WDFW has sufficient funding to conduct year 1 activities in the southwestern Cascades reintroduction area, but will need additional funding to complete the reintroduction project in this area. Additional funding from the National Park Service ($470,000) has been awarded to North Cascades and Mount Rainier National Parks to support this project and these funds may be available in 2016.

The completion of all or part of this project is dependent on obtaining sufficient funding to complete essential tasks and on the continued availability of fishers from the Province of British Columbia. Provincial officials have indicated their willingness to assist us in obtaining fishers for Washington reintroductions.

Suggested citation

Lewis, J. C. 2013. Implementation plan for reintroducing fishers to the Cascade Mountain Range in Washington. Washington Department of Fish and Wildlife, Olympia. 29 pp.