Jim Wilder was a young researcher on the frozen Beaufort Sea when he had his first polar bear encounter.

"We were camped out on the sea ice in front of a maternal den waiting for (mama bear) to come out with her cubs," he recalls. "A polar bear came up and sniffed the tent, right where my head was, when I was sleeping in the middle of the night and went on its merry way."

Wilder, now a scientist with the U.S. Fish and Wildlife Service in Alaska, is a co-author of a study analyzing all recorded cases of polar bear attacks on humans in the five countries where the animals live. He said his story shows why the popular idea of the great Arctic hunters as enthusiastic predators of humans is a myth.

"They're portrayed as these extremely dangerous man-eating beasts that are looking to attack people, which I think is fairly inaccurate."

Attacks aren't that common, he said. Although he acknowledges his list is incomplete and doesn't include data from Arctic aboriginals, Wilder's team found only 73 recorded predatory attacks in the 144 years between 1870 and 2014, 20 of them fatal.

The study, published in the Wildlife Society Bulletin, also suggests fat 'n' happy polar bears don't hunt humans.

Nearly two-thirds of the attacks were by young adult bears who were starting to starve.

The study only found 73 recorded polar bear attacks on humans in a 144-year period. (submitted by Kevin Xu) Almost all the attacks were by males, usually young. Of the 11 that weren't, most were females defending cubs.

Polar bears, said Wilder, avoid risk. Unlike black or grizzly bears, which can eat plants if necessary, polar bears must hunt.

"If they get injured, that impairs their ability to hunt," he said. "There isn't a lot of incentive for them to be aggressive — unless times are bad.

"That seems to flip a switch. They seem to turn into a different beast."

Even yearling polar bears will hunt people if they're desperate, Wilder said. And more than one-quarter of the attacks in the study occurred in towns.

Both circumstances are almost unheard of in grizzlies or black bears, he said.

Climate change could worsen conflicts

The findings suggest that human-bear conflicts are going to get worse as climate change whittles away at the sea ice the bears use as their main hunting platform for the fat-rich seals that form the biggest part of their diet. The report found that nearly nine in 10 attacks occurred between July and December, when the sea ice was at its lowest.

"If I lived in a coastal community, the things I would be worried about are loss of sea ice — more bears on shore, in poorer condition."

Geoff York, another co-author, said some Canadian Arctic communities have already noticed changes.

"We had stories from northern residents where they said, 'Growing up as kids, we used to go camping on the land in our wall tents. We don't do that any more. We have a fixed cabin with hard walls."'

Many community residents — especially those along the shores of Hudson Bay, where sea ice retreat is extensive and bear health is declining — are asking to be trained as qualified bear spotters to help protect industrial or scientific camps.

People need tools to live with hungrier bears that are going to be on shore longer, York said.

Polar bears have been known to make their way into Arctic communities on occasion in search of food, like this one in Tuktoyaktuk, Northwest Territories. Researchers suggest that climate change could make human/polar bear conflicts more prevalent in the future. (Kyla Lucas) Nunavut is issuing kits containing flares, bear bangers and bear spray to help keep hunters safe on the land. But those materials are considered hazardous goods and difficult to ship.

"A lot of the northern communities just don't have access to the less lethal deterrents," York said.

In the future, not all bear encounters will be as benign as the one Wilder recalls from that long-ago den stakeout.

"I look back on that with a little nervousness," he said. "I just thank my lucky stars that bear was probably in good or average body condition."