Graduation Date
Spring 2003
Document Type
Thesis
Program
Master of Science degree with a major in Natural Resources, option Wildlife
Committee Chair Name
Cynthia J. Zabel
Committee Chair Affiliation
Cal Poly Humboldt Faculty or Staff
Second Committee Member Name
Timothy E. Lawlor
Third Committee Member Name
T. Luke George
Keywords
x
Abstract
The Sonoma tree vole (Arborimus porno) is a California Species of Special Concern and an important prey species of the Northern Spotted Owl (Strix occidentalis caurina). Management of A. porno has been limited by the scarcity of biological data and a lack of understanding of its habitat requirements. I compared relative tree vole abundance among three size classes of Douglas-fir (Pseudotsuga rnenziesii) stands in 2000: pole (15-28 cm DBH), unthinned young-growth (29-61 cm DBH), and mature (>61 cm DBH). Four stands of each size class were searched for A. pomo nests using line transects on The Pacific Lumber Company lands in northwestern California. Ninety-two nests were found in mature, 13 in young, and 15 in pole stands. A one-way analysis of variance indicated that tree vole nests were significantly more abundant in mature than in young or pole forests, but there were no significant differences between young and pole stands. During 2001-2002, I evaluated the association between site-level habitat attributes and A. pomo abundance within Humboldt Redwoods State Park, Redwood National Park, and the Angelo Coast Range Reserve in northwestern California. Sixty-one sites were searched for A. pomo nests using line transects, and nest densities were estimated using program DISTANCE. I used generalized additive modeling to build predictive habitat models using an information theoretic approach and traditional stepwise regression. The
best fitting models using the information theoretic approach were single-variable models that included (in order of importance) percentage basal area of Douglas-fir, DBH of dominant trees, and total basal area. Results from the stepwise regression suggested that total basal area, percentage slope, and slope position were important predictors of A. pomo nest density. These models provide a quantitative assessment of habitat requirements important in the development of effective management strategies for the persistence and conservation of this species.
Recommended Citation
Jones, Jennifer M., "Habitat Associations and Ecology of Sonoma Tree Vole (Arborimus Pomo) in Northwest California" (2003). Cal Poly Humboldt theses and projects. 2621.
https://digitalcommons.humboldt.edu/etd/2621