This is a Final Status Report for the Fisher. The fisher was over-trapped in the 19th and early 20th centuries. Trapping, predator and pest control programs, and loss and alteration of habitat combined to push the fisher to near extirpation. Despite protection from legal harvest for 64 years, the fisher has not recovered. The fisher population may have been kept from recovering by a combination of factors.
Fisher biology is characterized by low population density and a low reproductive rate.
They have large home ranges and generally avoid large openings, which suggests that viable populations would require large areas of relatively contiguous habitat. In western Washington, fishers may have been restricted by frequent soft snows or deep snow packs to elevations below 1800 m. Forests with high canopy closure, multiple canopies, shrubs, and that support a diverse prey base are most used. Large diameter trees, large snags, tree cavities, and logs are most often used for den and rest sites, and are an important component of suitable habitat. Currently, the fisher is very rare in Washington.