Polar bears are apex predators in the Arctic, primarily hunting seals. Despite their formidable status, they can be preyed upon or their remains consumed under specific, uncommon circumstances.
The Primary Natural “Eaters”
The most direct natural scenario where a polar bear is “eaten” involves other polar bears. Intraspecific predation, including cannibalism and infanticide, occurs within the species. Adult male polar bears, in particular, are known to prey on cubs or smaller, weaker bears. This behavior can be motivated by resource scarcity, especially when primary food sources like seals are difficult to find. Additionally, infanticide by males may serve to bring a female back into estrus, allowing for new mating opportunities.
Rare Natural Encounters
While highly infrequent, other large Arctic animals can pose a threat to polar bears under specific conditions. Orcas, powerful marine predators, might attack a polar bear if it is in open water and vulnerable. Documented instances of orca predation are rare, but the possibility exists due to their opportunistic nature and size. Similarly, a large adult walrus, especially when defending its young, can inflict serious, even fatal, injuries using its formidable tusks. Walruses are particularly dangerous in the water, where they are more agile than polar bears.
Human Influence
Humans significantly impact polar bear mortality, though not in the traditional predator-prey sense of “eating” them. Subsistence hunting by Indigenous communities in the Arctic has been a long-standing cultural practice, providing food and materials. These hunts are now regulated and monitored by various agencies to ensure sustainability. Beyond hunting, accidental deaths can occur due to interactions with human infrastructure or communities. As sea ice diminishes, polar bears may spend more time on land, increasing the likelihood of encounters with people and leading to conflict, sometimes resulting in the bear’s death.
Consumption of Deceased Polar Bears
After a polar bear dies, its remains become a food source for various scavengers within the Arctic ecosystem. Animals like Arctic foxes, gulls, and even other polar bears will feed on a carcass. Wolves also scavenge on polar bear kills, driving off smaller animals to access the remains. In some instances, Greenland sharks have been found with polar bear remains in their stomachs, though the bears were likely already deceased when consumed. Scavenging plays an important role in nutrient cycling in the harsh Arctic environment.