Recent observations of intraspecific predation and cannibalism among polar bears in the southern Beaufort Sea
Intraspecific killing has been reported among polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus). Although cannibalism is one motivation for such killings, the ecological factors mediating such events are poorly understood. Between 24 January and 10 April 2004, we confirmed three instances of intraspecific predation and cannibalism in the Beaufort […]
Split Parturition Observed in a Captive North American Brown Bear (Ursus arctos)
Reproductive physiology in North American ursids is characterized by mating from spring to early summer, delayed implantation, and birth during hibernation. During spring 2008, a captive adult female brown bear was mated with two adult males. Pregnancy was determined by elevated progesterone concentrations during late fall before hibernation. Two male cubs were born on December […]