Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
Winisk Research and Consulting, Bellevue, Alberta, Canada.
PLoS One. 2021 Mar 3;16(3):e0247964. doi: 10.1371/journal.pone.0247964. eCollection 2021.
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.
已知有几种熊会故意在树木和其他物体上摩擦，但对于熊为什么要摩擦知之甚少。雄性和雌性棕熊（Ursus arctos）的摩擦行为模式表明，通过摩擦进行气味标记可以在潜在的配偶或竞争者之间进行交流。我们从 2011 年至 2014 年在艾伯塔省西南部从摩擦物体上收集的熊毛中提取 DNA，并利用来自蒙大拿州和不列颠哥伦比亚省东南部的现有 DNA 数据集，确定了每只被检测到的熊的性别和个体身份。利用这些数据，我们完成了亲子关系分析。根据亲子关系分析和检测数据，我们确定了每个通过我们的采样方法识别的棕熊的后代数量、伴侣数量、被检测到的独特摩擦物体数量以及被检测到的个体采样次数。通过泊松回归，我们发现熊的摩擦行为与繁殖成功率之间存在正相关关系；具有更多伴侣和更多后代的雄性和雌性熊在更多的摩擦物体上和更多的场合被检测到。我们的结果表明，熊的摩擦行为具有适合度成分，表明摩擦是适应性的，并为一种了解甚少的行为提供了深入的见解。
