Abstract
There has been only one study scientifically estimating the population size of brown bears (Ursus arctos yesoensis) on the Oshima Peninsula, Hokkaido, so far, although that estimate included a substantial margin of error. For more reliable results, we tried a mark-recapture method employing hair snagging. In the 3 years pre-survey, it was possible to get some hair samples using strained barbed wire and hanged lure in the middle of hair traps. Also, drying and storing hair samples properly in paper envelopes are essential procedures. Selecting adequate loci for individual identification is also important. Based on the results of the pre-survey, we conducted 3 years of hair snagging surveys using 29 or 39 hair trap sites. Through this latter survey, the homogeneity of habitat quality at each trap site and an adequate mesh size for population estimation are important issues to be considered.
