Walruses haul-out three weeks early, global warming blamed

An extremely early sea ice melt-off has sent thousands of Pacific walruses onto the beaches of northwest Alaska, placing pups in danger of being crushed on the crowded shoreline for the fourth year out of the past five due to the abnormal weather conditions.



This year's walrus haul-out, when the lumbering pinnipeds pull themselves ashore, comes a full three weeks earlier than last year's -- a potent symbol, environmental groups say -- that global warming is at work.



Last year, the walruses came ashore in late August. This year, some
began hauling out on August 7, almost three weeks earlier. Federal scientists say this massive move to shore by walruses is unusual in the United States. But it has happened at least twice before, in 2007 and 2009. In those years Arctic sea ice also was at or near record low levels.



The population of walruses stretches “for one mile or more. This is just
packed shoulder-to-shoulder,” U.S. Geological Survey biologist Anthony Fischbach said in a telephone interview from Alaska. He estimated their number at tens of thousands.



Scientists with two federal agencies are most concerned about the one-ton female walruses stampeding and crushing each other and their smaller calves near Point Lay, Alaska, on
the Chukchi Sea. The U.S. Fish and Wildlife Service is trying to change airplane flight patterns to avoid spooking the animals. Officials have also asked locals to be judicious about hunting, said agency spokesman Bruce Woods.



The federal government is in a year-long process to determine if walruses should be put on the endangered species list.



Fischbach said scientists don’t know how long the walrus camp-out will last, but there should be enough food for all of them.



During normal summers, the males go off to play in the Bering Sea, while the females raise their young in the Chukchi. The females rest on sea ice and dive from it to the sea floor for clams and worms. Walruses can dive down hundreds of feet to feed, which was easy to do when the ice came in near the shoreline where the water is shallow.



“When they no longer have a place to rest, they need to go some place
and it’s a long commute,” Fischbach said. “This is directly related to the lack of sea ice.”



In 2007, 2009, 2010 and now in 2011, the sea ice has melted so much that the only ice is far out to sea, where the sea bottom is as much as 10,000 feet down, too deep to use as a platform to feed from.



"Sea ice is an important component in the life cycle of walruses," said Chad Jay, research ecologist with the USGS Alaska Science Center. A federal marine mammal aerial survey over the Chukchi Sea in northwest Alaska this week spotted about 8,000 Pacific walrus on the beaches in the area. That crowding can lead to stampedes. In 2009 more than 130 young walruses were crushed when the group was startled.



"These large and potentially dangerous walrus haul-outs in the Chukchi Sea are a direct result of the extreme Arctic sea ice melt caused by
climate change," Geoff York, a biologist with WWF's Arctic Network Initiative, said in a release.



The U.S. Geological Survey Alaska Science Center Pacific Walrus Research Program is collecting data on walrus foraging behavior and movements throughout areas of the Bering and Chukchi seas during periods when sea ice is present and when sea ice is absent over the continental shelf.



Earlier in the week, Jeff Masters, director of meteorology at weather provider The Weather Underground predicted in his blog that arctic sea ice would have its lowest year since 2007.



Masters noted that according to sea ice maps kept by the University of Illinois at Urbana-Champaign's Cryosphere Today site, it is now possible to "sail completely around the North Pole in ice-free waters through the Northeast Passage and Northwest Passage."



This makes the fourth consecutive year--and the fourth time in recorded history--both of these Arctic shipping routes have melted free.
Mariners have been attempting to sail these passages since 1497. This year, the Northeast Passage along the north coast of Russia melted free several weeks earlier than its previous record early opening."



The amount of ice in the Arctic in July 2011 reached a record low. The average sea ice extent in that month was
3.06 million square miles, fully 81,000 square miles less than ice extent from the previous record low in 2007. But as a result of the record-setting ice melt, new shipping lanes have opened up in the North to ship goods between Europe and Asia.



Previously, transit across the northern sea route would require ice breakers to clear the way for cargo ships in the summer. But now the ice extent is 56% less than average in some areas, thus making travel across the
once dangerous Arctic waters “very easy” according to Russia’s environmental agency.



Loss of sea ice in the Chukchi this summer has surprised most scientists because last winter lots of old established sea ice floated into the region, said Mark Serreze, director of the National Snow and Ice Data Center in Boulder, Colo. But that has disappeared.



Although last year was a slight improvement over previous years, Serreze says there’s been a long-term decline that he blames on global warming.



“We’ll likely see more summers like this,” Serreze said. “There is no sign of Arctic recovery.”





Source:

USA Today,"Walruses haul-out three weeks early, global warming blamed", by Elizabeth Weise, accessed August 24, 2011

Washington Times, "Melting sea ice forces walruses ashore in Alaska", accessed August 24, 2011

The 9 Billion, "Record Low Arctic Ice Opens Up Ice-Free Northern Shipping Lanes", accessed August 24, 2011



Images: NASA Goddard Photo and Video, NOAA, USGS, Weather Underground, WWF

Sea Ice Extent image: National Snow and Ice Data Center


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