Tristan da Cunha Birds Dying in the U.S.
- Deaths of sea birds have wildlife officials puzzled
By JON W. GLASS
Norfolk, Virginia, USA
© July 2, 2005
VIRGINIA BEACH — Wildlife officials are investigating the mysterious deaths of hundreds of sea birds that have washed up on
beaches along the Atlantic coast since mid-June, including south of Sandbridge and on the Outer Banks. Most of the birds
have been greater shearwaters , which are now migrating north from their breeding grounds in the South Atlantic. The birds,
while fairly common, are rarely seen by beachgoers because they typically stay 30 to 100 miles offshore, where they feed on
small fish and squid.
Some of the birds have washed up alive, unable to fly and appearing weak, and later died. The number of dead birds has
alarmed wildlife officials, who are scrambling to pinpoint a cause.
More than 500 dead sea birds have been reported from Maryland to Florida since June 12, said Emi Saito, a wildlife disease
specialist with the U.S. Geological Survey’s National Wildlife Health Center in Madison, Wis. “It’s unusual to see so
many,” Saito said this week. Wildlife pathologists are examining the carcasses for exposure to toxins, pollutants such as
heavy metals and infections that might indicate a broader environmental concern, she said.
During the past week, staffers at the Back Bay National Wildlife Refuge in Virginia Beach have found about a dozen dead
greater shearwaters on the beach, said Dorie Stolley, a wildlife biologist. Only a few remained in good enough condition to
be examined, and the others were incinerated by city animal control officers, she said. Staffers used rubber gloves and
took other precautions while collecting the birds. People are advised not to touch dead birds they find on the beach.
Reports of dead birds also have come from Ocracoke and Hatteras Island on the Outer Banks. Diane Duncan, an ecologist with
the federal wildlife agency’s Ecological Services Office in Charleston, S.C., said the first reports came from Myrtle Beach,
Hilton Head and several nearby islands. Nearly 200 birds have washed up since then in South Carolina, Duncan said. “In 20
years here, I have never seen this kind of mortality event,” Duncan said. “It certainly is a concern to us, and we’d like to
know the cause.” Tests on two of the birds ruled out toxins found in red tide, a type of algal bloom that biologists
initially suspected as a culprit, Duncan said.
Will Post, an ornithologist and curator at The Charleston Museum, said he had dissected six greater shearwaters that had
washed up alive, unable to fly, and later died. The birds’ stomachs were empty, but they had varying levels of fat
reserves, suggesting that they did not die of starvation, Post said. “They were below normal weight, but that’s normal when
they’re in migration,” he said.
The shearwaters fly nearly 5,000 miles during their annual migrations to and from their nesting grounds on Tristan da Cunha,
a chain of volcanic islands in the South Atlantic, Post said. The cold-water birds breed in April and May and then fly to
their summer grounds off New England and points north, he said.
Islanders in the South Atlantic are allowed to harvest about 50,000 of the young birds a year for food, which is
controversial, Post said. There’s an estimated 5 million breeding pairs, he added. The birds resemble gulls in appearance
and size, with brown to gray heads and white undersides. They have webbed feet and dark, tube like bills. Since they spend
their lives at sea, Post said, they are able to drink salt water, excreting excess salt through special glands in their heads.
Reach Jon W. Glass at (757) 222-5119 or jon.glass@....
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Tristan da Cunha is a Dependency of St. Helena, a British Overseas Territory. BC