While Arctic sea ice reached a record low this summer, it is not widely known that almost all the ice that melted or drifted away was on the Russian, not the Canadian and Greenlandic side of the great northern sea.

One immediate consequence has been further grief and peril for Russia’s already seriously distressed polar bear population.

“It is worse for Russian polar bears than the bears in Canada or Greenland because the pack ice is retreating much faster in our waters,” said Nikita Ovsyannikov, deputy director of Russia’s polar bear reserve on Wrangel Island in the Chukchi Sea to the northwest of Alaska. “The best habitat is quickly disappearing. It is extreme.

“What we are seeing right now is very late freezing. Our polar bear population is obviously declining. It used to be that new ice was thick enough for them to walk on in late October. It now will happen much later.”

Figuring out how many bears still survived on and near the Chukchi Sea – home to the largest of Russia’s four polar bear populations – was difficult because they were spread across such a vast area, said the zoologist, who has spent his life studying bears in the High Arctic.

He guessed that the number of bears around the Chukchi Sea, which also sometimes migrate in small numbers to western Alaska, had dropped over the past three decades from “about 4,000 to no more than 1,700 at best.”

The retreating ice that has placed many Russian bears in a catastrophic situation has turned out to be a boon to the country’s Arctic mariners.

Taking advantage of the unprecedented sea conditions, dozens of freighters, including several mammoth 170,000-dead-weight-ton tankers, have used the Northeast Passage during the summer and fall of 2011 and again this year to bring as much as 110,000 tonnes of liquefied natural gas at a time from western Russia through the Bering Strait to China.

With no ice yet present near the Russian coast, there has even been talk that it might be possible to keep what is called the “Northern Sea Road” open until January.

The situation was so grave this year that sea ice that had already melted by July is not expected to return until as late as next January in the waters above the continental shelf where Russian polar bears traditionally spend a good part of their lives hunting from drifting ice for ring seals.

The explanation for the sudden, further decline in sea ice this summer was unusually low pressure in the Eurasian coastal seas and in the Beaufort Sea and East Siberian Sea, combined with unusually high pressure centred over Greenland and the North Atlantic, according to the U.S.-based National Snow and Ice Data Center. Air temperatures across the Arctic rose by as much as three degrees Celsius this summer.

With no drifting pack ice near the shore to hunt from, Russia’s polar bears have faced a stark choice. They either must go far out to sea on pack ice that has been drifting away from the coast in the late spring, or forage for food as best they can on Russia’s few Arctic islands or along the coast. However, venturing far from land presents special problems for female bears who traditionally build their hibernation and birthing dens on land.