Ice posing polar problems

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Even though the ice came early to Hudson Bay, it took too long for that ice to stay -- and experts say its slow formation sent some of Canada's polar bears to the brink of starvation.

Polar bears weren't able to get onto the ice to hunt seals until early December this winter, which observers say is becoming the norm.

"Those bears are all lining up along the coast line waiting for the ice to form," said David Barber, who holds the Canada research chair in Arctic science at the University of Manitoba. "They're basically all starving. They are really at their limit biologically."

Polar bears depend on winter seal hunting to build up enough fat to carry them through the lean summer months on land. The bears lose at least one kilogram of fat a day when they aren't on the ice. Given they are off the ice for up to 150 days, the hefty bears can lose well over 100 kilograms -- leaving some emaciated by the time the ice freezes again.

Andrew Derocher, a professor of biological sciences at the University of Alberta, and a science adviser with Polar Bear International, said he has been studying polar bears around Churchill for more than 30 years and the last few years have been the hardest on the animals.

"Sea ice has been declining globally," Derocher said. "It's not quite there for the failure of the polar bears on Hudson Bay -- will it be five, 10 or 50 years? I think it will be before mid-century."

Derocher said 30 years ago the ice on Hudson Bay stayed until early August and the water was iced over again by Remembrance Day.

But Derocher said scientists have followed the polar bears this year using radio transmitters on their collars and found some of them were having to come off the ice in June and they weren't able to get back on the ice until the first week of December.

"It used to be three months on land and now it is longer," he said. "This affects the pregnant female bears the most. They have already gone eight months without food and now it would be nine months. The longer the total ice-free goes the higher the mortality rates will be.

"If it is ice-free for 160 days or longer the mortality rates will go up dramatically."

In Churchill, tundra buggy tour operator John Gunter watched a "bizarre" season take shape along the shore. "The ice actually closed up earlier than it typically does, and we were really searching hard for bears," said Gunter, the general manager of Frontiers North. "The following week, the ice had broken up and a number of bears were forced back to shore."

Each season, Frontiers North works with researchers from institutions such as Polar Bear International and the World Wildlife Fund to keep tabs on the bears around the bay. One of the researchers, Peter Ewins, director of species conservation at World Wildlife Fund Canada, watched starving polar bears nosing around old grain stores and garbage dumps while others were found dead.

The odd berry patch and goose egg nest isn't enough to sustain the massive mammals, Ewins said. "The weaker individuals, the ones who are less proficient at hunting, they were in poorer condition and it was visible this year," he explained. "It's just an indicator that those less fit, poorer quality bears were really up against the wall already."

-- with files from The Canadian Press

melissa.martin@freepress.mb.ca kevin.rollason@freepress.mb.ca

Familiar temps on the horizon

While conditions near Hudson Bay seem to be approaching normal, the forecast for southern Manitoba also calls for temperatures to dip back down to where they usually are.

But first, one last push towards record highs in Winnipeg -- Tuesday's highest recorded temperature, 5 C, virtually tied the record high for Jan. 10 set back in 1990, when the thermometer struck 5.1 C.

Environment Canada predicts that today's temperature is expected to plummet to -17 C during a snowfall. Sunny skies are forecasted for the rest of the week, but even then we may not see the melting side of zero: Thursday's high is predicted at -18 C.

Republished from the Winnipeg Free Press print edition January 11, 2012 A2