Verification of a Forest Rating System to Predict Fisher, Martes pennanti, Winter Distribution in Sub-boreal Forests of British Columbia, Canada

Abstract

This study verified the ability of a forest rating system to predict the winter distribution of Fisher (Martes pennanti) in the Sub-boreal Spruce Biogeoclimatic Zone of central interior British Columbia. Forest polygons (i.e., homogenous areas with similar forest stand characteristics) were classified according to their age and structural development, canopy closure, basal area in mature trees, average tree diameter at breast height, and percentage of shrub cover. Approximately 170 km of transects randomly distributed across polygons were inventoried (snowshoed) from December to February 2005-2008. A total of 278 Fisher tracks were recorded. The observed frequency of Fisher tracks per polygon type was significantly (P < 0.05) different from expected. The majority (245 or 88.1%) of tracks were recorded in excellent- and high-quality polygons corresponding mostly to mixed coniferous stands. On average, these stands were 138.2 years old, and had 54.4% canopy closure, 38.1 m²/ha basal area, 27.8 cm dbh, and 11.4% shrub cover. This study showed that the forest rating system was adequate to predict Fisher winter distribution, and could be used to develop forest management plans that are compatible with the species habitat requirements.