Habitat selection by female black bears in the central Cascades of Oregon

Public scrutiny over management of black bears (Ursus americanus) in Oregon resulted in the passing of a referendum to ban the use of dogs and bait to hunt bears in 1994. Challenges to bear management necessitate the applicat ion of regionally derived biological information to hear management. The ov erall objective of this research was to define habitat characteristics that influence the autecology of female black bears in Oregon. Because habitat- selection processes operating at finer resolutions (e.g., the home range) a re inevitably the product of landscape characteristics, we chose to study s election at both the home range and landscape scale. We radio-tracked 14 ad ult female black bears from June 1993 to December 1995 in the central Casca des of Oregon to determine home-range size and analyze habitat selection. L ocations were classified to one of six habitat classes based on stand struc ture, and digitally overlaid onto a habitat map produced from a LANDSAT The matic Mapper scene of the study area. A geographic information system was u sed to determine habitat characteristics at known and random locations; chi -square and logistic regression techniques were used to analyze habitat use . Female black bears were associated with open-canopy sapling/pole and open canopy mature timber, apparently selecting for a combination of foraging o pportunities and security cover. Furthermore, black bears were negatively a ssociated with roads and positively associated with streams. Consequently, roads located along watercourses may inhibit the use of riparian areas by b ears. Understanding how forest-management practices influence the availabil ity and use of habitats for black bears, and applying this knowledge to bea r-management strategies, will ensure that management plans are based on the best available science, and confer greater credibility to state agencies f rom an increasingly informed and involved public.