The Ringed Seal
Their main prey is the ringed seal—full of fat and high in calories.
In fall, a seal cuts ten to fifteen breathing holes (known as aglus by Canadian Inuit) in the ice, using the sharp claws on its fore flippers.
Seals keep their breathing holes open all winter long, even in ice up to two meters (six feet) thick. They surface about every five to fifteen minutes at one of the holes or use air pockets trapped under the ice when available.
Polar bears attack by waiting for seals to breathe at the openings. They locate them with their powerful sense of smell and wait for the seals to emerge. Polar bears have to be smart and patient because the wait can be long—sometimes hours, or even days.
Bears also stalk ringed seals that are basking on ice by taking advantage of their sleep-wake rhythms.
The bear crawls slowly forward and freezes in place when the animal raises its head. At about six meters (20 feet) feet from the seal, the bear uses its explosive speed to pounce, killing the seal before it can escape back into the sea.
Dependence on Sea Ice
A polar bear’s hunting and eating patterns depend completely on sea ice.
Why? Because ringed seals depend on it—and ringed seals are the only food source with a high enough fat content and calories to keep a polar bear healthy.
Scientists have found that when polar bears dine exclusively on seal fat, their cholesterol levels drop lower than those of fasting bears, likely due to the protective quality of the omega-3 fatty acids found in the seals.
In summer when ice floes retreat, most polar bears follow the ice, sometimes traveling hundreds of kilometers to stay near their food source.
Polar bears who decide to come ashore face lean times in most of the Arctic. Catching seals in open water is no easy task.
Russian scientist Nikita Ovsyanikov once observed approximately 100 polar bears around a gray whale carcass.
Ovsyanikov has also seen fourteen polar bears eating shoulder-to-shoulder at a single walrus carcass.
Our own scientists routinely see groups of three or four male polar bears sharing a seal carcass on the shores of Hudson Bay during fall surveys.
According to Ovsyanikov, although one bear may own a large carcass, he won't object to sharing if his guests beg properly. A polar bear begs for food by approaching low to the ground, slowly circling around the carcass, and touching the nose of the bear in charge.
Watch polar bears as they travel across the sea ice to hunt seals.
Polar Bear FAQ
We answer the most frequently asked polar bear questions.