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Polar Bear (Ursus maritimus) Fact Sheet: Physical Characteristics

Physical Characteristics

Attribute Male Female
Body Weight

Typically 350–600 kg (775–1,300 lb)
Very large males up to 800 kg (1,760 lb)

150–290 kg (330–650 lb)
Some can be larger.

Shoulder Height Up to 1.7 m (5.6 ft)* Up to 1.7 m (5.6 ft)*
Body Length 240–260 cm (95–102 in) 190–210 cm (75–83 in)
Tail Length 7–12 cm (about 3–5 in) 7–12 cm (about 3–5 in)

*Alaskan brown bear is nearly the same size.

General Appearance

Largest living bear species

  • Occasionally exceeds 800 kg (1,764 lb)

Head and mouth

  • Neck is long and very thick
    • Wider than the head
  • Head elongated but smaller than that of other bears
  • Dentition reflects a strictly carnivorous diet
    • Slicing teeth (carnassials) well-developed for eating flesh
    • Canines elongated, conical and slightly hooked for grasping prey
      • Male canines very large
    • Molar surface area reduced (infrequently chew plants)
  • Ears relatively small

Feet and claws

  • Wide feet
    • Large, paddle-like
  • 5 toes on each foot
  • Claws non-retractable
    • 5–7 cm long
  • Soles of feet have small dermal bumps or papillae
    • May help with traction on ice

Other characteristics

  • Large amounts of subcutaneous fat
    • 5–10 cm thick in adults
    • Both blubber and pelt provide insulation
  • Experience little bone loss during prolonged, continuous denning period (Amstrup 2003)
    • Unique adaptation
  • Lack shoulder hump
  • Females have four functional mammae for nursing young
    • Other bears have 6
  • Liver tissue is toxic to humans, if consumed, due to its high levels of vitamin A (Amstrup 2003)

Sexual Dimorphism

  • Substantial sexual dimorphism (e.g., Derocher et al. 2005)
  • Males can be 2 times larger than females
  • Males have much longer foreleg guard hairs than females
    • May be used by females to select mates, or may make a male look larger to other males

Other Characteristics

Pelage and skin

  • Covered with fur, except for nose
    • Even foot pads are furred in winter
  • Thick underfur
    • 5 cm long
    • Tufted intermediate guard hairs (15 cm long)
  • Distinctive white hair
    • Translucent; no pigments
      • Probably arose from light-color phase brown bears that lived on Asian coast of Arctic Ocean
    • Color varies somewhat with season
      • Bears appear whitest after molt
      • Yellowish in summer due to oxidation by sun or oils from prey
    • Any green appearance from algae growing inside shaft of hollow guard hairs
      • More common in bears raised in managed care in warm climates
  • Black nose, skin, and claws


  • Sensitive over a wide frequency range
  • Respond to Ringed Seal's low-frequency vocalizations

Covered for the Cold

Polar bear black paws and nose

Polar bear black skin

Few parts of a polar bear's body lack fur. Even their foot pads may be furred during winter.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Page Citations

Amstrup (2003)
Cushing et al (1988)
DeMaster & Stirling (1981)
Derocher et al (2005)
Kurt (1990)
Nachtigall et al (2007)
Stirling (1993, 1998)

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