Planning for species of conservation concern requires an understanding of the biotic and abiotic factors that influence fitness. Fitness in wild populations is measured through survival and reproduction. Understanding the mechanisms that influence these population parameters is integral for elucidating links between habitat and species conservation. The fisher (Pekania pennanti) is a mid-sized, forest-dwelling carnivore of conservation concern in the western United States and is culturally-significant to many Native American communities in the Pacific Northwest. We evaluated the influence of environmental characteristics and forest management impacts on the reproductive success of fishers on the timber-managed forests of the Hoopa Valley Indian Reservation in northwestern California. We evaluated the effects of environmental characteristics and forest management practices in home ranges of adult female fishers using generalized linear mixed-effects models on three measures of reproductive success: denning attempts, the number of kits produced, and whether a female successfully raised a litter to weaning.
Results indicate middle-age (4-6 years old) female fishers were the most likely to attempt denning, produced the greatest numbers of kits, and had the highest probabilities of successfully weaning litters. We also found females with home ranges comprised of higher proportions of forests greater than 80 years of age had an elevated probability of denning. Managing for high rates of annual female survival and the retention of older forests on timber-managed landscapes are key components to the persistence and recovery of fisher populations. Future studies should investigate factors limiting annual female survival and provide management recommendations to increase female survival to foster higher rates of reproduction and the likelihood of population persistence and recovery.