Ain't Nothing Like Family - Brown Bears Share their Home Range with Relatives

Sociality in animal populations is a continuum, and interactions between conspecifics are meaningful for all vertebrates. Ignorance of social structures can lead to misunderstanding their ecology and, consequently, to unsuccessful species management. Here, we combined genetic and spatial data on radio-collated brown bears (Ursus arctos) to investigate kin-related home range overlap and kin-related centroid distance within central and eastern Finland. We found that the extent of overlap of home ranges was positively linked with relatedness among adult females. A similar positive correlation could be detected between home range centroid distance and relatedness among adult females. Moreover, there were significant differences between the two studied regions: female brown bears in central Finland were more closely related to each other, and the sizes of their home ranges were larger than those in eastern Finland. The smaller home ranges and lower degree of relatedness among bears in eastern Finland might be a result of the substantially higher hunting pressure in the area, combined with immigration of new unrelated individuals from Russia.