(Sept. 15) — Female walruses traditionally like to spend the summer lounging on slabs of sea ice with their young, occasionally dipping into shallow Arctic waters for a fishy treat. But over the past few weeks, thousands of these mammals have given up their free-floating lifestyle and taken up residence along the Alaska side of the Chukchi Sea. An estimated 10,000 to 20,000 Pacific walruses — mainly mothers and calves — are resting along the coastline, gathered together in tightly clustered pods, according to the U.S. Geological Survey. (Bulls normally splash around the Bering Sea in summer months.) Because only 20 percent of walruses normally come to shore, the Alaska Dispatch notes, scientists suspect another 80,000 walruses could be swimming close by. This is the third time such a sea-to-land migration — common in Russia, but historically unprecedented in Alaska — has taken place in the last four years. This unusual behavior appears to have been triggered by the slow warming of the Arctic waters through climate change, which in turn has shrunk the amount of thick, walrus-suitable sea ice. Last week, the U.S. National Snow and Ice Data Center reported that Arctic sea ice coverage had fallen to its third-lowest level since records began in 1979; only 2007 and 2008 saw lower levels. added by: TimALoftis
