Polar bears use a combination of body language and vocalizations to communicate.
- Head wagging from side to side often occurs when polar bears want to play. Adult bears initiate play—which is actually ritualized fighting or mock battling—by standing on their hind legs, chin lowered to their chests, and front paws hanging by their sides
- Nose-to-nose greetings are the way a bear asks another bear for something, such as food. The guest bear will approach slowly, circle around a carcass, and then meekly touch the other bear's nose. Bears who use proper manners are often allowed to share a kill.
- Chuffing sounds are a response to stress, often heard when a mother bear is worried for her cubs' safety. Mother bears scold cubs with a low growl or soft cuff. When a male approaches a female with cubs, she rushes toward him with her head lowered.
- Hissing and snorting and a lowered head all signify aggression.
- Loud roars or growls communicate anger.
- Deep growls are warnings, perhaps in defense of a food source.
- Attacking polar bears charge forward with heads down and ears laid back.
- Submissive polar bears always move downwind of dominant bears.
- Polar bear cubs make a variety of sounds from hums to groans to cries when communicating with their mothers. You can listen to some of these vocalizations in this blog post by a researcher.