Walruses Again Being Forced Ashore as Arctic Sea Ice Retreats

An animated map (click to see animation) from the U.S. Geological Survey (USGS) shows the daily locations of tagged walruses and sea ice distribution in the Chuckchi sea since 9 June 2010.  As the extent of Arctic sea ice again declines to one of the lowest levels on record -- especially off the coast of Alaska (see map below) --  watch the walruses congregate on the remaining ice and increasingly in "haul outs" along the Alaska shoreline.

As the sea ice retreats away from the shore, there is less and less ice available to the walruses -- mostly females and their young -- over relatively shallow waters where they can feed.  Ultimately, if they no longer can find ice over shallow waters, they must swim ashore -- sometimes over great distances. Those that survive the trip "haul out" along the shoreline where conditions tend to much less favorable than they would be on ice over shallow waters.

Walrus haulout near Icy Cape, 16 September 2009.  Source: USGS.

Under similar conditions in September 2009, large numbers of walruses hauled out along the Alaskan and Russian shores.  On 14 September 2009, scientists encountered 131 walrus carcasses near Icy Cape, Alaska.  A USGS report (Enumeration of Pacific Walrus Carcasses on Beaches of the Chukchi Sea in Alaska Following a Mortality Event, September 2009) said:

"All appeared to be young animals .... The events that led to the death of these animals are unknown, but appear to be related to the loss of sea ice over the Chukchi Sea continental shelf. In years prior to this event, other investigators have linked walrus deaths at other Chukchi Sea coastal haulouts to trampling, exhaustion from prolonged exposure to open sea conditions, and separation of calves from their mothers."

Carcasses of 131 young walruses litter the shoreline near Icy Cape, Alaska, in mid September 2009.  Source: USGS.

The outlook is not promising.  On 12 August, the USGS reported in Arctic sea ice decline: Projected changes in timing and extent of sea ice in the Bering and Chukchi Seas that for the Chukchi Sea, "projections show extensive ice melt during July and ice-free conditions during August, September, and October by the end of the century, with high agreement among models."

Dead calf walrus in front of the village of Wainwright 42 miles north of Icy Cape, Alaska, September 2009.  Source: USGS.

Online Resources:

For more on walruses, climate change and Arctic sea ice, see the following from our climate change blog:

• The Pacific Walrus says: "The time has come...We have many things to talk about, people!" 18 Aug 2010.
• Sea Ice Extent Far Below Previously Recorded Levels in Northern Route of Northwest Passage .  18 Aug 2010.
• Arctic Sea Ice in July is Second Lowest on Record, Maintaining Rapid Longer Term Decline. 8 Aug 2010.
• Average Arctic Sea Ice Extent Drops to Record Low for the Month in June. WWF Climate Blog, 7 July 2010.
• U.S. Fish and Wildlife Service Reports on Pacific Walrus and Polar Bear Stocks in Alaska.  3 Jan 2010
• Dramatic Footage Shows Consequences for Walruses as Arctic Warms. 1 Oct 2009
• Videos along with other multimedia materials related to walruses.
• As Arctic Sea Ice Reaches Annual Minimum, Large Number of Walrus Corpses Found Along Alaska Shoreline . 18 Sep 2009.
• As Sea Ice Reaches Annual Minimum, Impacts of Arctic Warming Grow. 16 Sep 2009.

See also:

• Unpredictable Arctic Ice Imperils Pacific Walrus.  Scientific American, 10 August 2010.
• National Snow and Ice Data Center. Includes Frequently Asked Questions about Arctic sea ice.
•  Center for Biological Diversity: Pacific Walrus
• Pacific Walrus Response to Arctic Sea Ice Losses. USGS fact sheet.
• US Fish and Wildlife Service, Walrus fact sheet [PDF].