Humans and other polar bears are the only predators of Ursus maritimus. Male polar bears may prey on cubs if they come into contact. Females with cubs tend to avoid other bears for this reason. Historically, polar bears have been hunted by the native peoples of the arctic for fur and meat. Commercial and sport hunting of polar bears increased in the 1900s as the price of pelts reached as much as $3000. (DeMaster and Stirling, 1981; Nowak, 1999)
- DeMaster, D., I. Stirling. 1981. *Ursus maritimus*. Mammalian Species, 145: 1-7.
- Nowak, R. 1999. Walker's Mammals of the World. Baltimore and London: The Johns Hopkins University Press.