Pacific Southwest Region
California, Nevada and Klamath Basin

Rare, Native Mammal Returns to Northern Sierra After 100 Year Absence

Dec 09, 2009

FOR IMMEDIATE RELEASE              Contacts: Dana Michaels (DFG) (916) 322-8911
December 9, 2009                                    Matt Baun (USFWS) (530) 340-2387
                                                              Mark Pawlicki (SPI) (530) 378-8104

 Rare, Native Mammal Returns to Northern Sierra After 100-Year Absence 

Stirling City (Butte County), Calif. – Two government agencies and a timber company today launched a seven-year study of the Pacific fisher, in the hopes of helping the species flourish.  The California Department of Fish and Game (DFG), the U.S. Fish and Wildlife Service (USFWS) and Anderson, California-based Sierra Pacific Industries (SPI) will collaborate on efforts to assess how fishers use northern Sierra Nevada forests where they have been largely absent for nearly 100 years.

In 2004, fishers were designated by the USFWS as a candidate for federal protection under the Endangered Species Act. In 2009, the Fish and Game Commission advanced the species to candidate and DFG began a status review. About the size of a house cat, fishers are members of the weasel family and are related to marten, otter and mink.

The species once ranged from California’s southern, central and northern Sierra to British Columbia, but loss of habitat due to timber management activities and fire suppression, coupled with past over-trapping, has reduced fisher populations in much of the west. Fishers have remained in two regions of the state – the southern Sierra Nevada, and in the Klamath and Coastal Mountains of northwestern California.

In order to facilitate the study, biologists today translocated two fishers to SPI-owned forests in the Northern Sierra from an existing fisher population in the Klamath Mountains. Fifteen total fishers are expected to be translocated over the next few weeks and an additional 25 fishers will join them over the next two years. Biologists will monitor the translocated fishers’ movements to learn how they use the habitat and to determine the effectiveness of translocation as a management tool for this species.

“Although fishers have been reintroduced in other states, this is the first attempt in California,” said Gary Stacey, DFG Northern Regional Manager. “If successful, this translocation will establish a new fisher population in California.  Since a primary conservation concern for fishers has been the reduction of their overall distribution, establishing them in a formerly occupied area is an important step toward strengthening the statewide population. By monitoring these fishers, we will learn a great deal about the way they use habitats and landscapes in areas where they historically occurred.”

“Fishers are in need of ambitious, scientifically sound, conservation measures throughout the West Coast and I thank the State of California for spearheading this effort,” said Ren Lohoefener, Regional Director of the U.S. Fish and Wildlife Service’s Pacific Southwest Region. “Not only will this study provide valuable information to help conserve the fisher, it is also a great example of how agencies can partner with private landowners to help ensure the species will continue to be around for generations.”

State and federal officials will assess the degree to which fishers use commercial forest land because much of the fishers’ historical range in the northern and central Sierra, as well as the southern Cascades, occurs on privately owned land.

“This project will take advantage of existing denning/resting habitat and potentially enhance the distribution of fishers in the wild,” said SPI biologist Amanda Shufelberger. “The reintroduction of the species on our forest land in this area could begin a new sustainable population, possibly becoming a vital link between northern and southern fisher populations that are now isolated,” added Shufelberger. 

To ensure scientific rigor of this study, USFWS and DFG have contracted with noted fisher expert Roger Powell of North Carolina State University to lead the research and monitoring of the translocated fishers. The study is being funded primarily by the USFWS and DFG. SPI has offered logistical support to track he fishers.

 Fisher Facts

  • Fishers are about the size of a large house cat. They are a member of the weasel family, which also includes minks, martens, otters, and wolverines. Fishers are estimated to live up to 10 years. The fisher is an opportunistic predator with a diverse diet that includes birds, rodents, reptiles, insects, and vegetation. Fishers are also one of the few known predators of porcupines.
  • The fisher’s range was reduced dramatically in the 1800s and early 1900s through trapping, predator and pest control, and alterations of forested habitats by logging, fire, urbanization and farming.
  • Fishers occur in the northern coniferous and mixed forests of Canada and northeastern U.S. In the western U.S., fishers are thought to have been extirpated in Washington and northern Oregon, and greatly reduced to scattered small populations from southern Oregon south to the southern Sierra Nevada in California. A recent translocation of fishers to Washington State’s Olympic National Park appears promising with evidence of reproduction in spring 2009. In California, fishers are now found only in two regions – the southern Sierra and in the Klamath and Coastal Mountains of northwestern California.
  • Fishers search for trees that provide adequate shelter. This means they will find cover in cavities in the trunks of trees, snags and hollow logs and platforms formed by mistletoe (‘‘witches brooms’’) or large or deformed branches.