It’s long been speculated that polar bears just might opportunistically feast on a caribou if given a chance, but up until recently, it has never actually been observed or filmed before.
Polar bears are the largest species of bear on earth and also the most carnivorous. While other species of bear frequently forage on vegetation, polar bears eat almost exclusively meat. Full-grown male bears weigh anywhere between 750 and 1,600-pounds, while adult females are about half that size.
The bears are specially adapted for frigid temperatures and spend most of their lives traversing sea ice and swimming in the open water while hunting for seals, which make up the vast majority of their diet. Polar bears actually spend so much time in the water that they’re classified as marine mammals.
Polar bears are native only to the arctic circle, including the far northern reaches of Alaska, Canada, Greenland, Norway, Sweden, Finland, and Russia. As the amount of sea ice in their range continues to shrink, the bears adjust their hunting techniques and evolve to meet whatever nature throws at them.
Remarkable footage recently shared by the Daily Mail shows a polar bear swimming down a caribou, or reindeer as they are called in Norway, shows how adaptable the big white bears are.
Scientists were observing the bear just outside of a research station when they noticed her sniffing the air downwind from a group of grazing caribou near the seashore. The bear slowly and discretely approached the herd before charging ahead towards one of the reindeer. The big bull tried to evade the attack by taking to the water, and although caribou are readily capable swimmers, it was no match for a bear built for the water.
The bear repeatedly sank its claws into the back of the caribou and submerged it under the water several times. Nevertheless, the caribou kept pushing towards shore with the attacking bear on its back. Once on dry land, the struggle ended pretty quickly, and for the next two hours, the bear proceeded to feast on venison while running scavengers like seabirds and Arctic foxes away from its stash.
Anecdotal evidence of polar bears hunting reindeer did not first emerge until 2000, but the behavior has never been documented or recorded on camera. Scientists speculate that with reduced ice cover in the area, the bears are teaching themselves new hunting techniques. Considering caribou are not evolved to protect themselves against a polar bear attack, they seem to be easy targets for the hungry bears.
“The level of alertness observed among reindeer is very low. When selecting feeding and resting sites, they appear to underestimate the risk of a bear attack.”
Additional research is underway better to better understand the ecological dynamics between polar bears and reindeer. Scientists hypothesize that localized populations of caribou could be hit hard if bears start focusing more time and energy on hunting them instead of seals.
There are also concerns about whether or not the caribou provide enough nutritional value to fuel the bears through the cold winters. Seals are covered in fatty blubber, which polar bears have evolved to digest, which provides them with energy reserves needed to survive the harsh and freezing climate of life in the Arctic.