Social discrimination by female polar bears (Ursus maritimus) when accompanied by dependent offspring during the ice-free season in southern and western Hudson Bay and James Bay

Description

Polar bears are generally described as solitary, but features of their life cycles and
habitats regularly necessitate interaction. Effective conspecific assessment, including accurate
recognition and discrimination, likely confers benefits, especially to females accompanied by
dependent young. Individuals in the Southern (SH) and Western (WH) Hudson Bay
subpopulations are ideal for studying polar bear social behaviours because of the prolonged
high densities of the ice-free season. First, I looked outside family groups to model their fine
scale sociospatial organization on land. Capture locations were more likely to correspond to
family groups when there were fewer neighbouring bears, when a greater proportion of
neighbours were female, and when the focal individual and neighbours were significantly
related. Second, I looked within the family group to assess offspring recognition. Of 288
offspring in 207 family groups captured in the SH subpopulation from 1999 through 2013, only
one case of adoption (of a singleton) was observed.
Author Keywords: Adoption, Kin Recognition, Logistic Regression, Maternity Analysis, Social Discrimination, Sociospatial