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We estimated black bear (Ursus americanus) population density in the Blue Mountains of northeastern Oregon based on summer mark-recapture surveys in 1996 and 1997. We developed a mark-recapture technique to estimate black bear density using houndsmen with dogs to detect bear scent on driving transects. We conducted 53 surveys and recorded 72 instances where dogs detected bear scent (a strike). We used strike frequency as a bear density index. Strike frequency did not differ between years; dogs detected bear scent at a rate of 1.47 strikes/20 km in 1996 and 1.18 strikes/20 km in 1997. We recorded each scent detection and pursued every bear to determine if the bear was marked or unmarked. On 55 occasions bears were treed after being pursued by dogs from transect routes; 33 of these were marked and 22 were unmarked. Applying the NOREMARK software, we estimated 59 bears in 1996 and 48 bears in 1997 in the 234-km2 survey area. We calculated a density of 25.2 bears/100 km2 in 1996 and 20.5 bears/100 km2 in 1997 in the survey area. This compares with a minimum known population density based on 3 years of marking bears prior to this study of 10.8 bears/100 km2 in the 485 km2 capture area that encompassed the survey area. We believe this technique holds promise as a practical tool for wildlife managers. Potential applications of this technique are to produce an index of black bear population trends or, in combination with other techniques, to more accurately assess density of a black bear population. The advantages, considerations, costs, concerns, and limitations of this technique are discussed.