- Wildlife Research and Management
- Wildlife Research and Management -- Non-Game Management and Conservation
Published: October 2006
Author(s): Jeffrey C. Lewis
Historically, fishers occurred throughout the forested areas of Washington State. They now appear to be extirpated, mainly as a result of overtrapping and habitat loss. A fisher status review completed in 1998 indicated that a reintroduction was the only way to recover fishers in the state. A feasibility assessment by Washington Department of Fish and Wildlife in 2004 concluded that a fisher reintroduction could be successful in western Washington and that the Olympic Peninsula was the most suitable location for the first reintroduction, followed by the southwestern Cascades, and then the northwestern Cascades. Feasibility of the reintroduction was based on the availability of suitable source populations (British Columbia or Alberta), a sufficient amount and configuration of suitable habitat, and a diverse prey base. A draft Washington State recovery plan for fishers identifies reintroductions on the Olympic Peninsula and in the Cascades and Selkirk Mountains as the main approach for recovery. This document describes the approach for implementing a reintroduction of fishers to Olympic National Park.
Fishers are native to the boreal and temperate forests of North America and have been translocated (i.e., reintroduced or augmented) throughout much of this range to restore populations that were extirpated through overtrapping and habitat loss. Fishers were translocated to reestablish a native species, a valuable furbearer, and a natural predator of porcupines. From 1947-2004, at least 35 fisher translocations were undertaken in 14 states and six Canadian provinces. Information from 29 of the 35 translocations was used to identify factors associated with translocation success. Twenty-three of the 29 (79%) were considered successful, including translocations in Oregon, Idaho, Montana, British Columbia and Alberta. Consequently, the fisher is considered one of the most successfully translocated carnivores.
Eight factors that could influence translocation success were compared using data from successful and unsuccessful translocations. These factors included the number of fishers released, sex ratio of released fishers, release type, release date(s), the number of consecutive years that fishers were released, the proximity of the source population, protection from commercial trapping, and protection from incidental capture. The number of fishers released and the number of consecutive years that fishers were released were significantly greater for successful translocations than for unsuccessful translocations. The other six factors were less significant in explaining translocation success.
Fisher populations in British Columbia and western Alberta are suitable source populations for a Washington translocation. Cooperation with provincial wildlife agencies and trapperâ€™s associations is necessary to effectively obtain fishers from either province. Obtaining fishers would require a provincial coordinator to oversee activities within the province; trapper cooperation in capturing fishers; a trapping coordinator to obtain fishers from trappers and transport them to a captive wildlife facility within the province; a captive wildlife facility to house fishers prior to transport to Washington; a captive wildlife specialist to provide care for fishers; and veterinary assistance for the examination, treatment, and health certification of fishers.
While in captivity, fishers will be examined, treated for injuries and parasites, given prophylactic vaccinations, and prepared for reintroduction. Individuals will be genotyped (a DNA sample will be taken), photographed, PIT-tagged, and equipped with a VHF radio-transmitter. Fishers will be fed to encourage weight gain before release.
Requirements for transporting fishers from a Canadian province to Washington include health certification by an accredited veterinarian, a possession and export permit from the provincial wildlife authority, an import permit from Washington Department of Agriculture, a U.S. Fish and Wildlife Service wildlifeimportation declaration form, approved shipping containers, and inspections by U.S. Fish and Wildlife officials and Canadian and U.S. Customs officials.
As an action proposed on federal lands, a proposed fisher reintroduction on Olympic National Park would require public disclosure and an assessment of reasonable alternatives as outlined in the National Environmental Policy Act (NEPA). The NEPA analysis for a proposed fisher reintroduction in Olympic National Park was initiated in 2005 and a draft environmental assessment is currently being developed and is expected to be released to the public by December of 2006.
If approved, a minimum of 100 fishers are planned for release in Olympic National Park over a 3-year period. Approximately 35 fishers will be released each year within three reintroduction areas in Olympic National Park: the Sol Duc-Elwha area, the Hoh-Bogachiel area, and the Queets-Quinault area. Fishers will be released in the fall and winter months in male-female pairs or small groups. Release locations will include sites along roads, trails, and river corridors within Olympic National Park.
Olympic National Park regulations would protect fishers from commercial harvest and incidental capture within park boundaries. A ban on the use of body gripping traps in Washington has resulted in fewer people buying trapping licenses and actively trapping. This reduction in trapping effort and the ban on body gripping traps would likely reduce the prevalence of incidental fisher captures and their severity on captured fishers, as fishers incidentally captured in cage-type traps (i.e., non-body gripping) are less likely to suffer severe injuries. The effect that commercial trapping or incidental capture by tribal trappers outside the park may have on reintroduced fishers is unknown, but it is not expected to significantly affect reintroduction success.
The reintroduction will be considered a success when a reproductive population of fishers is established in >1 of the 3 reintroduction areas. Monitoring efforts will be used to evaluate reintroduction success and allow mid-course adjustments to the reintroduction to increase its likelihood of success. Movements, survival, and home range establishment of fishers will be monitored beginning immediately upon release. Confirming reproduction will become a focus of the monitoring program during the denning season (March to June). Fishers will be monitored predominantly through aerial and ground telemetry. If additional funding is available, monitoring efforts could be expanded to use remote hair traps, track-plate and camera stations, or live trapping. Intensive monitoring efforts will be conducted in years 1-3, but monitoring could continue until year 5 or year 10 if additional funding becomes available.
A successful reintroduction would allow important opportunities for research on fishers in Washington. Extirpation prevented any previous opportunities to investigate basic biological and ecological characteristics of fishers in Washington. With additional funding, monitoring efforts could be expanded to conduct research on multi-scale habitat selection, demographics, population genetics, food habits, and dispersal of reintroduced fishers. This research would provide important information for the conservation of fisher populations and habitats on the Olympic Peninsula. It would also help improve the likelihood of recovering fishers throughout their historical range in Washington, and may help guide potential reintroduction efforts elsewhere in the west (e.g., the northern Sierra Nevada and southern Cascades of California, or the Coast Range and Cascades of northern Oregon).
Public outreach and input regarding the proposed fisher reintroduction on Olympic National Park was initiated in 2006 as part of the reintroduction NEPA process. An outreach program associated with an approved reintroduction proposal would likely include presentations, fisher web pages on the Washington Department of Fish and Wildlife and Olympic National Park web sites, the availability of fisher conservation planning documents, and possibly an â€�"adopt-a-fisherâ€ program.
A timeline and budget have been developed for a fisher reintroduction to Olympic National Park. They outline the timing and costs for obtaining, transporting, releasing, and monitoring fishers over a 3-year period.
The cost of these activities over 3 years is estimated at approximately $200,000/year. The U.S. Geological Survey has provided funding to support a significant portion of the monitoring efforts. Additional sources of funding will be pursued if the proposed reintroduction is approved by the National Park Service.