Polar bears are apex predators of the arctic ecosystem. Polar bears primarily prey upon bearded, ringed, hooded and harp seals, but they also hunt walruses, sea birds and small mammals. Because of their strong sense of smell, polar bears are also excellent scavengers, consuming significant amounts of carrion and human refuse. During the brief time when vegetation is available, polar bears consume flowers, leaves and berries.
Polar bears are the largest terrestrial carnivores in the world, reaching up to 1,760 pounds. As such, they have no predators other than humans and each other. While cannibalism is somewhat rare, it does occur from time to time. Polar bears capture their prey by relying on their superb senses, sharp claws, strong jaws and effective camouflage.
When polar bears die, they are eaten by a variety of scavengers. If they die on land, vultures, wolves and coyotes are among those that benefit most from the large carcass; if they die in the ocean, crabs and other bottom-feeding organisms consume the carcass.
Polar bears are a species classified as vulnerable to extinction. The primary threats to the bears are habitat destruction and climate change. Hunting was historically detrimental, but as of 2014, it's heavily restricted in most areas.