The Arctic sea ice has reached the third-lowest level ever recorded, and up to 200 walruses, which appear to be mostly new calves and yearlings, have been reported dead near Icy Cape on the north coast of Alaska – further evidence of global warming’s brutal transformation of the Arctic. Although the cause of the walruses’ death has not been confirmed, young walruses are vulnerable to being trampled to death in stampedes when disappearing sea ice forces walruses to come ashore in large numbers.
The National Snow and Ice Data Center announced last week that the Arctic summer sea-ice reached a minimum of 5.10 million square kilometers (1.97 million square miles) on September 12, making 2009 the third-lowest year on record behind 2007 (1.65 million square miles) and 2008 (1.74 million square miles).
Shaye Wolf, a biologist with the Center for Biological Diversity, said:
”The deaths of these walruses is another wake-up call that we will lose the Arctic if we continue on our current course. Every moment that Washington delays in taking strong action on climate change, it robs the walrus, the Arctic, and Arctic people of a future.”
The rapid melting of sea ice due to climate change is forcing the Pacific walrus, a resident of the Arctic seas between Alaska and Siberia, into a land-based existence for which it is not adapted. Walruses spend a significant proportion of its life on sea ice in pursuit of its preferred diet of benthic bivalve mollusks. Female walruses and their calves follow the sea ice year-round and rely on the safety of ice floes for nursing their calves and as essential resting platforms between foraging bouts, since they cannot continually swim. All Pacific walruses are dependent on sea ice for breeding activities in winter.
In 2007, the early and extensive disappearance of summer sea ice pushed females and calves onto the Russian and Alaskan coasts in abnormally dense herds. Russian biologists reported that 3,000 to 4,000 walruses, mostly young animals, died in 2007 after being crushed to death in stampedes. Last week, U.S. Geological Survey researchers reported a large herd of 3,500 walruses on shore near Icy Cape, as sea ice disappeared over their foraging grounds.
On September 8, the U.S. Fish and Wildlife Service announced it would conduct a full status review to determine whether the Pacific walrus warrants the protections of the Endangered Species Act.
The polar bear has also become an icon of global warming as the melting of its sea-ice habitat causes individual bears to drown, starve, and even resort to cannibalism. The Polar Bear Specialist Group now classifies eight of the world’s polar bear populations, including both of Alaska’s populations, as declining.
Shaye Wolf said:
“The climate bill needs to be significantly strengthened. The House legislation would not save the polar bear and the walrus and would give us less than a 50/50 chance of achieving the greenhouse gas reductions scientists say are necessary to head off devastating climate change. We can’t flip a coin with the fate of the planet. The Arctic is the Earth’s early warning system. If Congress and the Obama administration begin deep and rapid greenhouse pollution reductions now, we can still avert some of the most serious global warming impacts. But the rapid change underway in the Arctic shows that time is running perilously short.”
Current sea ice data is available at http://nsidc.org/arcticseaicenews/
Warming Will Change Arctic and Antarctic Ecosystems
Copyright © 2009 by Marine Science Today, a publication of OceanLines LLC