Hunting Strategies and Ecological Role

Key Insight

Polar bears are masters of diverse hunting strategies, particularly for their primary prey, the ringed seal. These methods include patient approaches, such as drifting toward a seal like an innocuous piece of ice, quiet swimming, flattening themselves on forequarters to slide across the ice and utilize cover, or building snow walls for concealment. A common and highly effective strategy is the patient wait at an 'aglu' (seal breathing hole), sometimes for three to four hours, where bears detect recent use by subtle ice accumulation or scent. Their attacks are swift, precise, and explosive, often centered directly over the seal's breathing hole in a snow lair, with a success rate ranging from 2 to 25 percent overall.

Their diet is extensive, extending beyond ringed seals to include other seal species like spotted, ribbon, harp, bearded, and hooded seals, as well as belukha and narwhal whales in leads and 'savssats.' They also prey on occasional muskox, walrus, dozing hare, or geese caught flightless during their molt, and consume bird eggs, seaweed, various tundra berries, and significant amounts of carrion, such as bowhead whale carcasses or beached walrus. This varied diet underscores their adaptability as top predators in the Arctic ecosystem, demonstrating intelligence and shrewd judgment in unfamiliar situations and novel approaches to common hunting challenges.

As a keystone predator, the polar bear plays a crucial ecological role by creating food for a retinue of scavengers. Healthy adult bears often consume only the blubber from a ringed seal kill, leaving the remaining carcass for arctic foxes, glaucous, Thayer's, and ivory gulls, and ravens, which are critically dependent on these kills, particularly in winter. While generally solitary, bears are not entirely unsocial; they aggregate in large numbers (e.g., 250 to 300 on Saint Matthew Island, or 56 at a whale carcass on the Svalbard coast) when food is exceptionally abundant or when waiting for sea ice, displaying minimal interaction except for aggressive encounters between males during breeding or between females and lone males.