Swindle, Keith A.; Ripple, William J.; Meslow, E. Charles; Schafer, Daniel. 1999. Old-forest distribution around spotted owl nests in the Central Cascade Mountains, Oregon. Journal of Wildlife Management. 63(4): 1212-1221.
Unlike previous spotted owl (Strix occidentalis) habitat association studies, we restricted our inquiry to the old-forest type and thus explored the association of spotted owls with habitat distribution as opposed to habitat type. We compared old-forest distribution around 126 northern spotted owl (S. o. caurina) nests in 70 pair territories, 14 nonreproductive spotted owl activity centers, and 104 points drawn randomly from old forest (closed canopy, >80 yr) in the central Cascade Mountains of Oregon. We quantified the percentage of oldforest within 50 concentric circular plots (0.1-5.0-km radii) centered on each analyzed point, and we used logistic regression to make spatially explicit inferences. Owl nests were surrounded by more old forest in plots with 0.2-0.8-km radii (P
Key words: forest fragmentation, habitat association, habitat selection, Landsat, landscape patterns, northernspotted owl, Oregon, Pacific Northwest, Strix occidentalis caurina.