Normal swimming speed for walruses is about 7 kph (4.3 mph). They are capable of short bursts of up to 35 kph (21.7 mph).

Most propulsion comes from alternate strokes of the hind flippers. Foreflippers also work with the hind flippers for maneuvering.

Walruses generally breathe at the surface for about one minute after every five to eight minutes of subsurface activity. They can stay submerged for as long as 10 minutes.

A walrus's bottom-dwelling prey usually inhabit waters no more than about 80 m (262 ft.) deep: a walrus generally dives no deeper than this. Deeper dives, however, have been documented. When the stomach contents of one individual were examined, researchers concluded that the walrus dove to at least 91 m (299 ft.). Another observation confirmed a dive of 113 m (371 ft.) and submersion time of 25 minutes.

All marine mammals have special physiological adaptations for diving. These adaptations enable a walrus to conserve oxygen while it is below water.

A walrus breathes through its nostrils and through its mouth.

Heat loss in water is 27 times faster than in air.

A walrus's core body temperature is about 36.6ºC (97.9ºF). There is a heat gradient throughout the blubber to the skin. The skin stays about 1º to 3ºC (1.8º - 5.4ºF) warmer than the water.

From about -20º to 15ºC (-4º - 59ºF) a walrus's metabolism doesn't change, and the temperature doesn't appear to affect the walrus's behavior.

Walruses can withstand even cooler temperatures; they have been observed at -35ºC (-31ºF).

In cold water, blood is shunted inward as blood vessels in the skin constrict, reducing heat loss to the environment. The skin appears pale, almost white.