Tim McBride, PhD

Tim McBride

Major Advisor: Gary Roloff

Area of Experitise: Forest Management and Western Gray Squirrels

Research: The western gray squirrel is listed as a threatened species in Washington. Forest management activities that are proposed in occupied western gray squirrel habitat are regulated by the Washington Department of Natural Resources often in consultation with Washington Department of Fish and Wildlife (WDFW). Timber harvest and western gray squirrel conservation are often viewed as incompatible. Squirrels are known to occupy harvested sites in eastern Washington forests yet viability of these squirrel sub-populations is uncertain. Regulatory effects on timber harvest tend to focus on the protection of squirrel nests, with the assumption that buffering each nest and providing connectivity are critical to conservation. Nests are difficult to detect and the relationship between nest occurrence, abundance, and spatial configuration to squirrel abundance and habitat quality is poorly understood. WDFW acknowledges that nests only provide an index to squirrel abundance; i.e., nests do not necessarily reflect population demographics. Additionally, current strategies for conserving western gray squirrels in managed forest landscapes focus on nest trees and individual patches containing those trees, with little consideration given to the larger scale configuration of suitable habitats that should form the basis for a landscape-level squirrel conservation strategy. With little information on the relationships between squirrel populations and nest abundance and the ability of western gray squirrels to move through fragmented landscapes, the goal of this study is to document the relationship between detected nests and squirrel abundance. Under the current survey, regulatory, and landscape planning techniques that are available to private landowners in Washington, this information is critical to effectively conserve western gray squirrels and aid in population recovery. I will develop a detection probability model for western gray squirrels nests, determine the relationship between squirrel nests and squirrel abundance, and quantify the spatial characteristics of squirrel habitat use in managed landscapes.

Gray Squirrel