The most obvious physical characteristic of the walrus is the presence of large tusks in both the male and female. These tusks, which are canines, can reach lengths of 1 meter (the average size is 50 cm), and are usually longer and heavier in the males (bulls) than in the females (cows). Accompanying the tusks are stiff beard bristles, called vibrissae, and although individual variation in length is great, the bristles can grow up to 30 cm long. The bristles are replaced yearly. In natural environments these bristles are often quite worn. Bulls are physically larger than the cows, growing to lengths of 3 m compared to 2.6 m for cows. Aside from the conspicous beards, both males and females appear almost completely bald. In fact, they are covered with short coarse hair that becomes less dense as the animal ages. Their skin, which lies in many folds and wrinkles, can be 4 cm thick. This tough skin is the thickest on the neck and shoulders of adult males. As walruses age their skin becomes paler. When the animals enter the water they become even paler as blood flow to the skin is restricted. Conversely, when walruses are warm their skin is flushed with blood and they appear to be very red, almost "sunburned." Walruses have no external ears and their eyes are small and piglike (Lawlor 1979, Nowak 1991, Parker 1990).
Range mass: 400 to 1700 kg.