In the summer of 2014 an emaciated male polar bear was scowling around a large ice sheet in the Svalbard Archipelago.

Based on the size of its frame, it may not have eaten for many months. It was extremely lean. It was in the thinnest category researchers use to describe levels of fat stores. 

It was critical for the bear to find food and fast.

The previous record was 72 seconds in 1970

The bear saw three bearded seals in the open seawater. He saw his chance. Slowly, he slipped into the water and aimed for the closest seal, a so called "aquatic stalk".

This is a stealthy practice. It’s where a bear sneaks up on prey. First it will glide soundlessly through the water, locate a seal’s exact location, before diving and stalking it from below.

But most come up periodically to check they are still aiming for the right place, often hiding behind chunks of ice.

This particular bear didn’t.

The first seal may have heard a splash, it started to look from side to side and 32 seconds after the bear first dove, it also disappeared under water. The next seal was 12-13 metres further away.

It was only after three minutes and ten seconds that the bear "exploded out of the water and propelled itself halfway onto the ice immediately in front of one of the second seal," the researchers noted.

The bear did not surface, but carried on to the second seal

He was observed by ecotourism guide Rinie van Meurs, the captain of the ship, and several passengers and crew. The team filmed the event so were later able to confirm that its head did not pop above water so it could breathe.

It was the longest observed dive for a polar bear to date. The previous record was 72 seconds in 1970.

After all its effort, this dive did not go well for the hungry bear. Although he grabbed one of the seal’s flippers momentarily, he did not manage to catch it.

Instead, he watched the seal swim away while he rested his paws on an ice sheet, panting heavily for 20 seconds before turning once again to the water to look for more seals.

We don’t know how long polar bears can hold their breath. They may be able to do so for even longer.

This particular bear was so emaciated that he may not have been able to store as much oxygen as a fatter bear could.

This is an example of some of the fascinating things one can learn simply by watching animals

When he was back on land, Van Meurs sent the video to polar bear researcher Ian Stirling from the University of Alberta, Canada. He confirmed it was a new record. The finding is published in the journal Polar Biology

"The dive was much longer than anything we expected," says Stirling. "In fact, when the first seal went down, we thought the dive would be over.

"However, the bear did not surface but carried on to the second seal. This was really unusual and gave new insights into what the bears are capable of mentally."

The observation shows that polar bears may have evolved this ability as a specific adaptation to its marine environment.

Polar bears and brown bears only separated from a common ancestor about 500,000 years ago, which in evolutionary terms is very recent. That they developed such super-powered lungs so quickly is surprising.

"This is an example of some of the fascinating things one can learn simply by watching animals and letting them tell one about themselves," Stirling says.

Polar bears will starve when their food sources diminish

However, the researchers warn that this ability may not be enough for the bears to survive in their habitat. The bears live on ice sheets; they use them to hide behind when sneaking up on prey. But the sea ice they depend on is rapidly shrinking due to a warming climate.

This means they will have to swim in open water for longer periods of time, making them much more obvious to the seals that they hunt.

"Increased diving ability cannot evolve rapidly enough to compensate for the increasing difficulty of hunting seals," the researchers say.

Only last week another study found that the issues facing polar bears are more serious than thought. Writing in the journal Science, researchers warned that polar bears will starve when their food sources diminish because of climate change.

Others had proposed that they might enter a state of active hibernation when food is scarce. When researchers followed over 20 bears in Alaska, they realised this was not the case. They do not adapt to low food stores, they simply starve.

The incredible diving skills of polar bears may help them sneak up on prey in open water in the short term, but the outlook is grim.

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