The smell of success: Reproductive success related to rub behavior in brown bears

• Published in: PLOS ONE
• Main Authors: Morehouse, Andrea T., Loosen, Anne E., Graves, Tabitha A., Boyce, Mark S.
• Other Authors: Apollonio, Marco, Alberta Conservation Association, Alberta Ecotrust Foundation, Alberta Environment and Parks, Alberta Innovates Bio Solutions, Alberta Sprot Recreation Parks and Wildlife Foundation, Disney Worldwide Conservation Fund, Drywood Yarrow Conservation Partnership, Glacier National Park, International Association for Bear Research and Management, Minister's Special License, Miistakis Institute, Nature Conservancy of Canada, Natural Sciences and Engineering Research Council of Canada, National Science Foundation Division of Environmental Biology, Parks Canada, Safari Club International Foundation, Safari Club International Northern Alberta Chapter, University of Alberta, Shell Canada, TD Friends of the Environment Foundation, U.S. Geological Survey, U.S. Bureau of Land Management, U.S. Forest Service, Waterton Biosphere Reserve Association, Yellowstone to Yukon Conservation Initiative
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2021
• Subjects: Ursus arctos
• Online Access: http://dx.doi.org/10.1371/journal.pone.0247964; https://dx.plos.org/10.1371/journal.pone.0247964

Several species of bears are known to rub deliberately against trees and other objects, but little is known about why bears rub. Patterns in rubbing behavior of male and female brown bears ( Ursus arctos ) suggest that scent marking via rubbing functions to communicate among potential mates or competitors. Using DNA from bear hairs collected from rub objects in southwestern Alberta from 2011–2014 and existing DNA datasets from Montana and southeastern British Columbia, we determined sex and individual identity of each bear detected. Using these data, we completed a parentage analysis. From the parentage analysis and detection data, we determined the number of offspring, mates, unique rub objects where an individual was detected, and sampling occasions during which an individual was detected for each brown bear identified through our sampling methods. Using a Poisson regression, we found a positive relationship between bear rubbing behavior and reproductive success; both male and female bears with a greater number of mates and a greater number of offspring were detected at more rub objects and during more occasions. Our results suggest a fitness component to bear rubbing, indicate that rubbing is adaptive, and provide insight into a poorly understood behaviour.