Male reproductive input, breeding tenure, and turnover in high-density brown bear (Ursus arctos yesoensis) populations on the Shiretoko Peninsula, Hokkaido, Japan

Male reproductive behavior has not been thoroughly investigated in large, non-social mammals. We studied male reproductive input using field observations and microsatellite DNA data for the brown bear (Ursus arctos Linnaeus, 1758) population in a special wildlife protection area on the Shiretoko Peninsula in Hokkaido, Japan. We identified the father of 82 offspring born between 2006 and 2018 from 54 litters produced by 20 females and revealed that they were sired by a total of 19 males. Overall, paternity was distributed relatively evenly among different males, although litter production tended to be skewed to a few bears in some years. Male breeding tenure varied among individuals, but most tenures were within the range of 1 to 6 years. Human-caused mortality, mostly occurring near human residential areas, induced male turnover, indicating that the special wildlife protection area located in the inner part of the peninsula is not free from human impact. The frequency of successful reproduction was highest in 10–14-year-old bears, which is consistent with the period when males reach physical maturity. These results contribute to an understanding of breeding systems in large solitary mammals and to appropriate conservation and management strategies for brown bear populations.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author