Inbreeding depression in brown bear Ursus arctos Original Research Article

This note reports the occurrence of inbreeding depression in a captive brown bear Ursus arctos population. We analyzed studbook records of brown bears bred in Nordic zoos and found a significant reduction in litter size following an increase of inbreeding. In addition, albinism is associated with inbreeding in this population. The amount of depression is compared to that found in other species. Our results are in disagreement with the contention that mammalian carnivores are adapted to close inbreeding.