Starvation Suspected in Massive Die-off of Alaska Seabirds

http://abcnews.go.com/US/wireStory/starvation-suspected-massive-die-off-alaska-seabirds-36229541

By dan joling, associated press
ANCHORAGE, Alaska — Jan 12, 2016

Seabird biologist David Irons drove recently to the Prince William Sound community of Whittier to check on a friend's boat and spotted white blobs along the tide line of the rocky Alaska beach. He thought they were patches of snow.

A closer look revealed that the white patches were emaciated common murres, one of North America's most abundant seabirds, washed ashore after apparently starving to death.

"It was pretty horrifying," Irons said. "The live ones standing along the dead ones were even worse."

Murre die-offs have occurred in previous winters but not in the numbers Alaska is seeing. Federal researchers won't estimate the number, and are trying to gauge the scope and cause of the die-off while acknowledging there's little they can do.

Scientists say the die-offs could be a sign of ecosystem changes that have reduced the numbers of the forage fish that murres depend upon. Warmer water surface temperatures, possibly due to global warming or the El Nino weather pattern, may have affected murre prey, including herring, capelin and juvenile pollock.

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An estimated 8,000 of the black and white birds were found dead on the Whittier beach, said John Piatt, research wildlife biologist at the U.S. Geological Survey's Alaska Science Center.

"That's unprecedented, that sheer number in one location is off the charts," he said.

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"The length of time we've been seeing dead birds, and the geographic scope, is much greater than before in other die-off events," said Kathy Kuletz, a biologist for the U.S. Fish and Wildlife Service. "We're looking at many times that. So possibly a good chunk of the population."

In 2008, Irons was lead author on a research paper that correlated natural die-offs to climate change and rising ocean temperatures. Using data from murre colonies around the circumpolar north, researchers found murres died in years when ocean surface temperature water increased by just a few degrees.

Murre prey such as capelin, a forage fish in the smelt family, live in a narrow band of cool water, said Irons, who retired last year after 36 years with the Fish and Wildlife Service in Alaska and California.

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The USGS National Wildlife Health Laboratory in Madison, Wisconsin, has examined about 100 carcasses and detected no parasites or disease that may have contributed to murres not eating, said wildlife disease specialist Barbara Bodenstein.

If the die-off is tied to low numbers of forage fish brought on by a warming ocean, the rest of 2016 does not bode well for murres, Piatt said.

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