Too Much Spring Ice Threatens Alaskan Polar Bears

It’s threatening polar bears, because when the ice in the Beaufort Sea (north of Alaska) is as thick as it is now, ringed seals, the bears’ primary prey, aren’t able to drill through the ice to make breathing holes. When the ice is too thick, the seals move elsewhere where they can create breathing holes, and the polar bears often end up starving.

CNS News talked with Dr. Susan Crockford, an evolutionary biologist in British Columbia who’s studied polar bears for most of her 35-year career:

Five meters of ice – about 16 feet thick – is threatening the survival of polar bears in the Southern Beaufort Sea region along Alaska’s Arctic coast. “Prompted by reports of the heaviest sea ice conditions on the East Coast ‘in decades’ and news that ice on the Great Lakes is, for mid-April, the worst it’s been since records began, I took a close look at the ice thickness charts for the Arctic,” Crockford noted in her Polar Bear Science blog on April 18th.

“Sea ice charts aren’t a guarantee that this heavy spring ice phenomenon is developing in the Beaufort, but they could be a warning,” she wrote, noting that they “don’t bode well” for the Beaufort bears.

“What happens is that really thick ice moves in because currents and winds from Greenland and the Canadian islands push it against the shore,” Crockford told CNSNews.com.

“The male seals arrive in the area in early spring to set up breeding territories. They drill a hole through the ice to maintain breathing holes close to the shore. But there’s a limit. They can drill through two meters (about seven feet) of ice. But too much beyond that and they’re in trouble.”

“The reason that’s important is that seals mate right after the pups, who are born in April, are weaned. So the male seal wants to be there, but he has to have breathing holes. If the ice is too thick, he has to move off someplace else,” she explained.

But this is the same time that female polar bears are just emerging with their newborn cubs from maternity dens either on or near the shore.

“When those bears come out of their dens in the spring, they need to find seals right away because they will have gone six months without eating,” Crockford said. “If there are no seals, they have to go further out, where there’s thinner ice.”

“Spring and early summer are really a critical time for polar bears. That’s when they need to eat as many seals as they can because that’s when they put on fat for the rest of the year. If they have trouble doing that in the spring, they’re in big trouble.”

There were comparably high levels of spring ice in the Beaufort Sea in 2004 and 2006, when bear counts were “one of the pieces of evidence used to have the bears listed as ‘threatened’ in the U.S.,” Crockford pointed out.

“Polar bear biologists were finding some bears quite thin and found a population decline,” she said, which they attributed to melting summer ice caused by global warming.

“But the biologists were not there to see the thick [spring] ice. All they saw was thin bears,” she pointed out. “They blamed the poor condition of the bears on summer ice, instead of acknowledging that it was likely the condition of the ice in the spring that was the cause of the problem.”

Alas, liberals will call her a “science-denier” and “flat-earther” for daring to question the religious dogma of global warming hysteria.