Kin-related spatial structure in brown bears Ursus arctos

• Published in: Behavioral Ecology and Sociobiology
• Main Authors: Stoen, O. G., Bellemain, E., Saebo, S., Swenson, J. E.
• Other Authors: Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences (NMBU), Laboratoire d'Ecologie Alpine (LECA), Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Biotechnology and Food Science, Norwegian Institute for Nature Research (NINA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2005
• Subjects: dispersal; genetic distance; matriline; social structure; philopatry; geo; envir; Ursus arctos
• Online Access: https://doi.org/10.1007/s00265-005-0024-9; https://hal.archives-ouvertes.fr/halsde-00294532

International audience Kin-related social structure may influence reproductive success and survival and, hence, the dynamics of populations. It has been documented in many gregarious animal populations, but few solitary species. Using molecular methods and field data we tested: (1) whether kin-related spatial structure exists in the brown bear (Ursus arctos), which is a solitary carnivore, (2) whether home ranges of adult female kin overlap more than those of nonkin, and (3) whether multigenerational matrilinear assemblages, i.e., aggregated related females, are formed. Pairwise genetic relatedness between adult (5 years and older) female dyads declined significantly with geographic distance, whereas this was not the case for male-male dyads or opposite sex dyads. The amount of overlap of multiannual home ranges was positively associated with relatedness among adult females. This structure within matrilines is probably due to kin recognition. Plotting of multiannual home-range centers of adult females revealed formation of two types of matrilines, matrilinear assemblages exclusively using an area and dispersed matrilines spread over larger geographic areas. The variation in matrilinear structure might be due to differences in competitive abilities among females and habitat limitations. The influence of kin-related spatial structure on inclusive fitness needs to be clarified in solitary mammals.