Socially induced delayed primiparity in brown bears Ursus arctos

摘要: Reproductive suppression through behavioral or physiological means is common in group-living and cooperative breeding mammals, but to our knowledge it has not been shown wild large carnivores other than those with a clear form of social organization. Brown bear (Ursus arctos) females matrilinear assemblages related using largely exclusive area. Behavioral reproductive might develop due hierarchical system among within assemblage inbreeding avoidance, because male brown bears can overlap their daughters. We tested whether natal dispersal influenced the age primiparity. predicted that emigrant females, geographically removed from maternal paternal influence, would reproduce earlier philopatric females. The average primiparity was 4.3 years dispersed outside mother’s home range (n=8) 5.2 (n=10). Only range, body size, mass, growth, local population density, father’s had significant influence on ultimate role for likely avoid minimize resource competition. Due low risk frequent exposure young unrelated males, we conclude competition female hierarchies causes