Cascades Fisher Reintroduction Project: Progress Report for March 2017 to February 2018


Published: March 2018

Pages: 20

Author(s): Jeffrey C. Lewis, Tara Chestnut, Jason I. Ransom, and David O. Werntz


Fishers (Pekania pennanti) are a mid-sized member of the weasel family (Mustelidae) that historically occurred in the dense coniferous forests of Washington (Powell 1993, Lofroth et al. 2010). Unregulated harvest, loss and fragmentation of habitat, and predator control campaigns beginning in the late 1800s collectively resulted in the decline and extirpation of fishers from Washington by the mid-1900s (Lewis and Stinson 1998). Consequently, the fisher was listed as an endangered species in the state, and recovery actions have been outlined to restore fishers in Washington (Lewis and Hayes 2004, Hayes and Lewis 2006).

Given the success of reintroductions for restoring fisher populations (Lewis et al. 2012), Washington Department of Fish and Wildlife (WDFW), the National Park Service (NPS), and Conservation Northwest (CNW) have partnered to plan, implement, and monitor the success of fisher reintroductions on the Olympic Peninsula (Lewis 2014, Happe et al. 2017) and the Cascade Range in an effort to restore fishers in the largest portions of their historical range in Washington.

Planning for the Cascades fisher reintroduction project began in 2013 with WDFW¡¦s Implementation Plan for Reintroducing Fishers to the Cascade Range in Washington (Lewis 2013). Mount Rainier National Park and North Cascades National Park Service Complex led the National Environmental Policy Act process and completed a Fisher Restoration Plan / Environmental Assessment in May 2015 (NPS 2015). Project partners worked with the British Columbia Ministry of Forests, Lands and Natural Resource Operations (FLNRO), British Columbia Ministry of Environment (MOE) and the Tsilhqot'in, Secwepemc, and Dakelh First Nations to obtain an approved capture and transport permit for the capture and translocation of up to 160 fishers over five years to Washington. Planning efforts also required contracting with organizations to 1) coordinate trapping efforts with licensed British Columbia trappers, 2) house and care for captive fishers, and 3) provide veterinary services for health inspections and preparing fishers for release. These planning efforts were completed by October of 2015.

Our goal is to re-establish a self-sustaining fisher population in both the southern and northern portions of the Cascade Recovery Area as outlined in the fisher recovery plan for Washington State (Hayes and Lewis 2006). To accomplish this goal, we have the following objectives for each portion of the Cascade Recovery Area:

  • Objective 1: Capture a founder population of 80 fishers (~40F and ~40M) from central British Columbia (or other appropriate source population) and release them in the southern portion of the Cascade Recovery Area (Figure 1) over 2-3 years, followed by another 80 fishers in the northern portion over 2-3 years.
  • Objective 2: Release fishers at few (2-3) locations at each of the two portions of the Recovery Area to increase the likelihood of fishers interacting, i.e., finding mates, and learning habitat suitability from previously released fishers.
  • Objective 3: Release as many fishers as possible before January 1st, so that the stress of the reintroduction process occurs well before the active gestation period of female fishers (from late-February to late-April), which is expected to improve reproductive success.
  • Objective 4: Monitor post-release movements, survival, home range establishment, and reproduction to evaluate initial success of the reintroduction project during the 3-4 years when we can track fishers with functioning radio-transmitters.

In this report we provide a detailed summary of progress of the fisher reintroduction project in the southern Cascade Range in Washington made from March 2017 to February 2018. A detailed summary of the process and methodologies of this fisher reintroduction project was provided in the previous progress report (Lewis et al. 2017).

Suggested citation

Lewis, J.C., T. Chestnut, J.I. Ransom, and D.O. Werntz. 2018. Cascades Fisher Reintroduction Project: Progress Report for March 2017 to February 2018. Washington Department of Fish and Wildlife, National Park Service, and Conservation Northwest, unpublished progress report. Washington Department of Fish and Wildlife, Olympia, WA. 20 pp.