Everything is playing out on the Norwegian archipelago of Svalbard on August 21, 2020, when the sea ice has receded and, with them, the seals whose bear feeds: a young bear chases a male reindeer in freezing water, catches up with him , drowns him and brings him back to earth to devour him.

Stunned, a team from a nearby Polish science station films the scene, documenting for the first time a hunt involving the two mammals.

"It looked like a documentary," Izabela Kulaszewicz, a biologist at Gdansk University, told AFP.

"You could almost hear the voice of the narrator in the background saying that you absolutely must watch this event because we will probably never see anything like it again."

A sequence so atypical that with two other researchers, she draws one.

According to them, the episode is part of a series of observations suggesting that the polar bear falls back more frequently on terrestrial prey to overcome the difficulty of putting the paw on seals.

In Svalbard, a territory a thousand kilometers from the North Pole, where signs warn against the predator, some 300 sedentary bears live alongside about 20,000 reindeer.

According to the authors of the article, signs of predation between the two species have increased in recent decades.

A polar bear devours the carasse of a reindeer in Svalbard, Norway, August 21, 2020 Izabela KULASZEWICZ AFP

There are two explanations for this: the retreat of the pack ice which keeps bears on the mainland longer and the multiplication of the number of reindeer in Svalbard since their hunting was banned there in 1925.

This predation, apparently new, should not be overinterpreted, however, note other experts.

"If polar bears were killing reindeer in the 1950s or 1960s, it would have been very difficult to observe because there were few people, few bears and few reindeer" at the time in Svalbard, argues Andrew Derocher , professor at the University of Alberta.

Opportunistic hunter

Although ringed or bearded seals, with their highly calorific fat, are their favorite delicacies, bears are opportunists who have also been observed to feed, chicks, rodents and even.

With its 70 and 90 kg in adulthood, reindeer would also be a good food supplement for bears in summer, a period of "lean cows" which tends to lengthen with warming.

Road sign warning of the presence of polar bears in Svalbard, Norway, September 25, 2021 Olivier MORIN AFP / Archives

Two days after being filmed by Polish researchers, the same bear was observed devouring another reindeer carcass.

"Reindeer can be important, at least for some bears, when they have to stay on the ground for long periods of time," says Norwegian expert Jon Aars, co-author of the article.

According to experts, however, this adapted diet will not be a lifeline for the polar bear.

"While an occasional successful predation attempt on reindeer may be good in the short term for one or two bears (and the media), I think it does little for the polar bear or reindeer population," said the professor. Ian Stirling of the Canadian Wildlife Service.

A skilled swimmer - his Latin name is ursus maritimus - the polar bear simply cannot compete with the reindeer over long distances on land, or overheat.

Elsewhere in the Arctic, caribou, the name given to reindeer in North America, are not as easy prey as their cousins ​​in Svalbard, whose vigilance seems to have eroded since their hunting was banned.

The polar bear Jonathan WALTER AFP

"They are also larger animals and have co-evolved with terrestrial predators, namely wolves, wolverines and grizzly bears on the tundra, which makes them more difficult prey," observes Geoff York of the protection organization. Polar Bears International.

Even in Svalbard and the surrounding region, the future looks bleak for bears.

"There is not enough ice to support a population of polar bears", judge Andrew Derocher.

"Given the trend, I think the Barents Sea polar bear population, which includes Svalbard, will be one of those that will be lost in this century."

© 2021 AFP