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A polar bear spent over three minutes underwater hunting seals, breaking the previous record of 72 seconds, according to a Dutch seaman who filmed the sickly beast's failed attempt to find nourishment in a changing climate.
Rinie van Meurs, an arctic adventurer who regularly takes tourists to watch polar bears on the remote Norwegian islands of Svalbard, published his observations in the journal Polar Biology, along with Canadian researcher Ian Stirling.
It was August 19, 2014, the water "as calm as a mirror," when van Meurs first spotted the thin, ailing bear to the north of the island of Spitsbergen in the Svalbard Archipelago.
"He was literally skin and bones," he told VICE News.
The bear caught a glimpse of three bearded seals lounging near the edge of a wide open ice floe, across nearly 600 feet of open water. The animal dove underwater and swam toward his prey. After 30 seconds, the nearest seal "became vigilant" and escaped into the sea, but the others seemed to remain oblivious to the danger of the frail, but still dangerous, ursine predator that stalked them from the depths.
Minutes pass with no movement, the video shows, until a white mass of fur rockets out of the water, striking toward the second seal.
"He suddenly emerged like a torpedo out of the water and tried to grab the seal on the ice floe," van Meurs said. "He almost got it — just touched it by the flipper."
The seal got away, and the bear lay exhausted and panting, with one paw resting on the ice. Van Meurs was shocked by how long he had gone without air.
"When we replayed the video," he recounted, "we thought, 'Crikey! This is 3 minutes and 10 seconds. This is pretty long!"
He contacted his old friend Ian Stirling, a University of Alberta professor, who had once witnessed a polar bear remain underwater for 72 seconds, the longest dive recorded to date.
The pair wrote an article retelling the now record-breaking tale, and warning that bears are being forced to resort to extremes to find food as ice floes melt sooner every spring, shortening the time they can hunt. The pair noted that the maximum dive duration for a wild polar bear is unknown, and that opportunities to document such episodes are rare.
Van Meurs cautions that the bear's emaciated condition may not have stemmed directly from global warming. He suspects that the bear was old and that his hunting skills had begun to fade.
But the warming climate has caused ice to break up earlier over wider areas during the past few years, reducing the amount of thick multiyear ice, which provides more cover for bears to sneak up on unwitting seals. In this case, the combination of a flat, featureless floe and wide open water forced the bear to dive much earlier than usual.
"As the climate continues to warm and the amount of sea ice in the circumpolar Arctic continues to decline," van Meurs and Stirling wrote, "access to seals on ice floes may become progressively more difficult owing to the presence of more water between floes and earlier seasonal disappearance of ice altogether."
"If the ice floes are more compact he can sneak around the ice floes and use that to obstruct himself," van Meurs further explained. "This bear had no choice but to stay underwater."
Roughly 2,000 to 5,000 polar bears remain around the Barents Sea, which borders Svalbard. Ice coverage in the area has declined, on average, by hundreds of square miles between 1979 and 2010. Van Meurs has seen signs that climate change is altering their behavior, and reducing the number of young bears that reach adulthood.
He's noticed that fewer mother bears are managing to access their traditional denning areas, which are now cut off from the main Islands by wider spans of sea in most years. Even more troubling, he hasn't seen a single young bear in the past three years, apart from newborns, perhaps suggesting that few are managing to survive past their first year.
As starvation becomes a grim reality, some bears are turning to even more desperate measures to feed. A 2006 study found that one mother polar bear fell victim to cannibalism from hungry neighbors while still in her den. Intraspecies attacks are not uncommon, but observed episodes of cannibalism had been very rare.
Van Meurs and Stirling wrote that a "fatter and more buoyant" young bear might be able to remain underwater longer, if forced to do so. But they warn that there are limits to how much bears can adapt to the changing conditions driven by climate change.
Polar bears may have already evolved to stay underwater for longer periods, the authors noted. But that took place over hundreds of thousands of years, they point out, and the climate is now changing too quickly for evolution to keep up. Though most populations are currently stable, some scientists believe that the number of polar bears could decline by two-thirds by mid-century if the current rate of sea ice loss continues.
"If more water opens up, bears will have to go to the extremes of their capacity to make their hunt successful," van Meurs told VICE News. "And the question is: how far can they go to make a living? If the ice keeps receding with the speed it is now, then at some point it goes beyond their capacity, and they lose."
Follow Arthur White on Twitter: @jjjarthur