Another wildly alarmist article by Margaret Munro

Meier says there is a possibility the ice melted back during warm spells 8,000 and 130,000 years ago. But he stresses this is the first time humans have played the lead role in driving the retreat.
...
Researchers headed north in record numbers this year to chart the transformation underway in both the ice and Arctic ecosystems. There are reports this year of starving polar bears resorting to cannibalism. And there are dwindling numbers of walrus, which spend much of their time on and around ice floes, feeding on mollusks, which are getting harder to reach as the pack ice shifts north over deeper waters.

About those walrus stampedes

When I read stuff like this, I'm also not completely convinced that walruses are threatened with extinction:

...researchers have encountered herds as large as 100,000 in recent years...

When I read this in the "walrus" Wikipedia entry, I'm also not convinced that lack of summer ice is necessarily a big deal:

In the non-reproductive season (late summer and fall) walruses tend to migrate away from the ice and form massive aggregations of tens of thousands of individuals on rocky beaches or outcrops....In late spring and summer, for example, several hundred thousand Pacific Walruses migrate from the Bering sea into the Chukchi sea through the relatively narrow Bering Strait.