Skip to Main Content
Selection of rest structures and microsites by fishers in OregonAuthor(s): Keith B. Aubry; Catherine M. Raley; Patrick G. Cunningham
Source: The Journal of Wildlife Management. 114: 79-91.
Publication Series: Scientific Journal (JRNL)
Station: Pacific Northwest Research Station
Download Publication (666.0 KB)
DescriptionMost previous studies of resting habitat for fishers (Pekania pennanti) in the Pacific coastal region of the western United States and Canada were focused on habitat conditions within rest sites (typically ≤0.5 ha), which include the rest structure (e.g., live tree, snag, log) at its center. Studies of selection for rest structures were sparse and compared characteristics of rest structures to those occurring within rest sites; none investigated selection by sampling resource availability throughout the study area. In addition, limited data were available on the use of rest microsites (e.g., mistletoe brooms, platform branches, cavities) by fishers, and no studies have quantified their availability. To better inform forest management activities designed to improve resting habitat for fishers, we documented use of rest structures and microsites throughout the year by 12 female and 7 male fishers on the west slope of the Cascade Range in southern Oregon, USA from 1995 to 2001, systematically sampled the availability of rest structures and microsites, and used logistic regression modeling to investigate selection of rest structures. Fishers primarily used live trees (65%), snags (14%), and logs (16%) for resting; in all 3 resulting models, the characteristic that best distinguished used from available rest structures was the presence of a suitable rest microsite: mistletoe broom or cavity in live trees, cavity in snags, and hollow end in logs. Only the snag and log models included covariates associated with tree size, likely reflecting the need for enclosed rest microsites (cavities, hollow ends) to be large enough to contain an adult fisher. We then used our availability data to model the ecological characteristics associated with mistletoe brooms in live trees, cavities in snags, and hollow ends in logs. Whether a tree was a hemlock (Tsuga spp.) had the greatest effect on the presence of suitable mistletoe broom microsites, but the most important characteristics of snags with cavities and logs with hollow ends were being in moderate stages of decay and relatively large in diameter at breast height (snags) or diameter 3 m from the large end (logs). Forest structures containing suitable rest microsites for fishers were uncommon in our study and may represent a limited resource. Accordingly, we recommend that management of resting habitat for fishers be focused on retaining relatively large structures that already contain suitable rest microsites, rather than simply retaining the largest available structures. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
- Visit PNW's Publication Request Page to request a hard copy of this publication.
CitationAubry, Keith B.; Raley, Catherine M.; Cunningham, Patrick G. 2018. Selection of rest structures and microsites by fishers in Oregon. The Journal of Wildlife Management. 114: 79-91. https://doi.org/10.1002/jwmg.21479.
KeywordsFisher, habitat selection, Oregon, Pekania pennanti, rest microsite, rest site, rest structure.
- Invasive scotch broom alters soil chemical properties in Douglas-fir forests of the Pacific Northwest, USA
- Pruning high-value Douglas-fir can reduce dwarf mistletoe severity and increase longevity in Central Oregon
- Pruning dwarf mistletoe brooms reduces stress on Jeffrey pines, Cleveland National Forest, California
XML: View XML