Movements of northern flying squirrels in different-aged forest stands of western Oregon

In western Oregon, northern flying squirrels (Glaucomys sabrinus) are the p rimary prey species for northern spotted owls (Strix occidentalis caurina), an old-growth associated species. To assess differences between old-growth and second-growth habitat, we livetrapped and radiotagged 39 northern flyi ng squirrels to estimate their home range sizes and describe movements in 2 old-growth and 2 second-growth conifer forest stands in the Cascade Mounta ins of central Oregon. Sampling periods were summer and fall of 1991-92. Ho me range sizes averaged 4.9 ha and did not differ (P > 0.30) between the 2 stand types. Male northern flying squirrels had larger (P less than or equa l to 0.03) mean home ranges (5.9 +/- 0.8 ha; (x) over bar +/- SE; n = 20) t han females (3.9 +/- 0.4 ha; n = 19). Northern flying squirrel movement dis tances between successive, noncorrelated telemetry locations averaged 71 m (n = 1,090). No correlation was found between distances moved and stand typ e or sex. Northern flying squirrel's home range sizes, movements, and densi ties were similar between the 2 stand types. We suggest abundance and movem ents of northern flying squirrels are not influencing the preferential sele ction of old-growth forests by northern spotted owls.