Jan 25

A polar bear has been recorded swimming continuously for over nine days, a feat of endurance which could reveal the potential impacts of climate change.

Photo of polar bear swimming

Polar bears have large, strong limbs and huge forepaws which are used like paddles when swimming.

The price of a long swim

The long-distance swim, covering an incredible 687 kilometres (426 miles), was undertaken by a female polar bear fitted with a GPS collar which allowed scientists to track the bear’s movements.

Photo of polar bear cub peering over adult female

A polar bear cub remains dependent on its mother for around two and a half years, but may be unable to endure the high costs of a long swim.

Although polar bears are often known to swim between land and sea ice to hunt seals, this long journey came at a high cost to the female bear. In the two months over which she was followed, the female lost 22 percent of her body fat, and also lost her yearling cub, for which the long swim would have been even more energetically costly.

Climate change a threat to polar bears

The results of this study, published in the journal Polar Biology, demonstrate the remarkable swimming abilities of polar bears, but also the potential risks of a changing climate. Scientists fear that increased melting of sea ice as a result of global warming may force polar bears to undertake more frequent, longer journeys through freezing waters, at a potential cost to their health and the survival of their cubs.

Photo of polar bear leading cub across melting ice

The main threat to the polar bear is believed to be melting of Arctic sea ice as a result of climate change. This species is listed as Vulnerable by the IUCN.

According to George Durner, one of the scientists who undertook the study, “We are in awe that an animal that spends most of its time on the surface of sea ice could swim constantly for so long in water so cold. It is truly an amazing feat.” However, he adds that their dependency on sea ice “potentially makes polar bears one of the most at-risk large mammals to climate change.

Read the full story in the BBC’s article.

Watch underwater footage of a polar bear swimming on ARKive.

Liz Shaw, ARKive Species Text Author

  • Keisha L. (January 25th, 2011 at 9:59 pm):

    i just love animals hope the climate doesn’t change for these polar bears

  • Kath (January 26th, 2011 at 9:13 pm):

    I think a male bear wouldnt have had the stamina or fat layers possibly? Truely amazing journey. Wonderful creatures.