Global warming could be driving polar bears to eat dolphins, a behavior never before seen in the wild. As the Arctic region warms, dolphins are starting to travel further north during colder months than ever before, where some are being devoured by polar bears.

The cold-weather mammals usually feed on seals for most of the year, as dolphins usually only enter the Norwegian Arctic in summertime, after ice melts. The dolphins have never before been seen in the area during the winter or spring, but the behavior was also seen, out of season, in April 2014.

Jon Aars at the Norwegian Polar Institute collected images of polar bears hunting and killing dolphins, and storing meat away in frozen storehouses for later consumption. In one set of pictures, a thinly built male bear is seen eating one dolphin, and taking another kill to a snowbank, where it buried the carcass for later consumption. Such an act has never before been seen by biologists.

"We think that he tried to cover the dolphin in snow in the hope that other bears, foxes or birds would have less of a chance of finding it. Maybe to be able to eat it a day or two later, once he had digested the first one," Aars said.

During recent years, the region has seen nearly ice-free winters, and receding levels of ice. Researchers believe these conditions may have encouraged the dolphins to travel into the region. Ice blown into a fjord by strong northerly winds may have trapped the animals in the area. As they come up through holes in the ice to breathe, they make themselves targets for hungry polar bears.

"Even if they saw the bear, the dolphins did not necessarily have any other choice," Aars told the press.

Since that first report of dolphins eaten in the Arctic by polar bears, the same behavior has been witnessed five additional times. Some of the dolphins may have been stranded by the harsh climatic conditions in the Arctic.

Polar bears will eat a wide variety of foods, including occasionally feasting on small whales when they are able to gain access to the marine mammals. Because of this, biologists do not believe that eating dolphins is that great of a change for the Arctic mammals. What is more of a concern are rising temperatures in the Arctic, and how that could affect the biosphere.

Pictures and research of polar bears in the wild eating dolphins were published in the journal Polar Research.

Photo: Eden, Janine, and Jim | Flickr