This data package contains tabular data collected during 2013-2016 for the determination of the status of reintroduced fishers on the Olympic Peninsula.

The fisher, Pekania pennanti, once occupied coniferous forests at low to middle elevations throughout much of the Western United States, but was extirpated from Washington State during the last century. The fisher was listed as a State endangered species in October 1998. In 2006 Washington State developed a Fisher Recovery Plan, with a goal of establishing multiple self-sustaining fisher populations in Washington.

In 2007, the NPS and WDFW completed a Fisher Reintroduction Plan and Environmental Assessment for Olympic National Park. The goal of that effort was to restore fishers to Olympic National Park (ONP) and Washington State. The project was designed to take up to 10 years to complete, and to be conducted in two phases. During Phase 1, 90 fishers were translocated from central British Columbia to the Olympic Peninsula from 2008 to 2010, and the initial success of the reintroduction was monitored by radio-tracking translocated fishers (2008–2011). Data were collected on post-release survival, movements, home-range establishment, and reproduction. Initial findings indicate that survival was highly variable among release years. In addition, access constraints in a large wilderness area prevented the reliable determination of breeding success for most of the released females, creating additional uncertainties about the current status of reintroduced fishers on the Olympic Peninsula. The need for a second monitoring phase, consisting of non-invasive surveys of fisher distribution, was identified in both the State and Federal fisher recovery planning efforts. The goal of Phase 2 of the fisher monitoring in the Olympic Recovery Area was to evaluate the status of reintroduced fishers on the Olympic Peninsula from 2013–2016.

A fisher occupancy study was conducted from 2013 to 2016 on the Olympic Peninsula to evaluate the success of the reintroduction of 90 fishers from 2008 to 2010. The objectives of the study were to determine the current fisher distribution, the proportion of the recovery area currently occupied, and the genetic characteristics and reproductive success of the fisher population, via DNA analyses. The initial findings indicate that fishers are widely distributed across the Olympic Peninsula both inside and outside the recovery area, and the presence of second and third generation fishers indicates substantial reproductive success by founder individuals and their descendants.

Data within this package include data for sampling locations, sample site visits, photo results, and genetic data.