Scott Schliebe / USFWS

As Arctic ice melted to the smallest extent in human history — a loss that stunned scientists and exceeded worst-case scenarios in climate models — the U.S. Fish and Wildlife Service was collecting comments on new research into the fate of polar bears north of Alaska.

These nine studies, released in early September, predict that most polar bears will disappear if the Arctic ice continues to retreat during summer. Conducted as part of the agency’s proposal to list polar bears as threatened with extinction under the Endangered Species Act, the studies are sobering.

polar bear leaps ice floes
Credit: UNEP

Eliminate the ice habitat where polar bears hunt, rest and build dens, and you eliminate the bears. Two-thirds of the iconic white predators will starve, fail to reproduce, cannibalize each other and drown as their essential ice platform dissolves into slush. The process is irreversible, the scientists say.

Now people have additional time to digest the reports and make comments on the science, the agency announced this week. The comment period originally closed Oct. 5, but now remains open until Oct. 22.

During the first comment period on the proposal to protect the bears under the federal act, the agency received more than 600,000 comments. The deadline for making a decision is looming: January 7, 2008.

Bear scientists have long been warning about the impact of sea ice retreat on polar bear health and populations, and conservation groups have made it a rallying cause in their campaigns to raise awareness over climate change. For background, check out the our original story on this subject.

You think polar bears have got problems? Imagine the ice-free life facing the walrus.

These behemoths like to ride the ice floes over relatively shallow beds chock full of clams and other invertebrates. They dive for their meals, then rest on the ice.

But with Arctic floes hundreds of miles further north than ever before, plus drifting over water that can be thousands of feet deep, walrus have converged on the Alaska coast, repeating a spectacle reported last summer on the Russian Arctic coast.

The Associated Press’s Dan Joling offered this dispatch:

Walrus hauled out on shore in Alaska
Credit: USFWS

Thousands of walruses since late summer have congregated in haulouts on Alaska’s northwest shore, a phenomenon likely connected to record low Arctic sea ice.

Joel Garlich-Miller, a walrus expert with the U.S. Fish and Wildlife Services in Anchorage, said Thursday animals began showing up on shore in late July, a month earlier than usual.

By August, several thousand animals – far more than normal – were bunched up in haulouts in a stretch of coastline from Barrow, America’s northernmost community, to Cape Lisburne, about 300 miles to the southwest on the Chukchi Sea, as first reported by The Arctic Sounder.

“It’s raising a bunch of conservation issues for us,” Garlich-Miller said.

With walrus struggling to adapt, polar bears on the brink of ecological catastrophe — and sea ice gone brittle and slushy — a coalition of environmental groups have challenged the federal government to update stock assessments for polar bears, walrus, sea otters and manatees.

“Environmentalists sued the federal government Thursday for allegedly failing to adequately track populations of marine mammals threatened by global warming,” according to an AP story out of San Francisco.