Scientists look for North America's bird flu carrier

The search for the first wild bird carrying a deadly flu virus to North America is under way on a lonely stretch of coastal salt marsh on the outskirts of Alaska's largest city.

Biologists are ankle-deep in mud and yellowed marsh grass, trying to net and test two types of shorebirds. Both are known to visit regions where flocks have caught the dangerous H5N1 virus that has spread across Asia and even into Europe and Africa.

"Birds up here are going to be interacting with birds that are going to be moving back in the United States. This is kind of Grand Central Station," said Paul Slota of the U.S. Geological Survey, who will be overseeing the testing of samples back at the USGS wildlife lab in Madison, Wisconsin.

The focus now is on long-billed dowitchers and pectoral sandpipers, just two of the 28 bird species that come to the great avian mixing zone that is Alaska. If bird flu can be carried long-distance by wild birds, experts hope to see it first here, before the fall migration through other U.S. states.

Of course no one knows if the H5N1 flu will arrive on the wings of a migratory bird. Or if it will reach this continent this year. But if it does, U.S. wildlife officials want to stop it from spreading through many bird species and threatening domestic poultry.

Bird flu has killed or led to the slaughter of millions of chickens and ducks in Asia. It has infected more than 200 people who had very close contact with poultry. Of the known human cases, about half of the victims have died.

The big fear is that this virus will mutate into a virulent form that can easily infect people and spread among them.

But for now the mission at hand is swabbing the back sides of dowitchers and sandpipers to get fecal samples that will be tested for bird flu. The project is so massive, Alaska biologists have faced a swab shortage. Nationwide, the goal is to sample 75,000 to 100,000 wild birds.

The long-billed dowitcher is a 10-inch gray shorebird with long legs. It breeds in high-latitude coastal wetlands in Alaska, Canada and the Russian Far East.

Those that breed in Russia range near H5N1 outbreak areas in Asia and mix with birds that could be infected. Then they pass through Alaska in spring and fall.

Half of the world's pectoral sandpipers breed in Alaska or Canada, the other half in Russia. Small numbers of Siberian birds winter in Southeast Asia, Australia and New Zealand and have the potential to pick up the virus along the way.

Each May, some pectoral sandpipers make a stop on the Anchorage salt marsh, a beach of mud, grass and brackish ponds that stretches a thousand feet to Cook Inlet. The view is magnificent, across the water is Mount Susitna, known locally as Sleeping Lady because of its resemblance to a woman reclining on her side, but the standing water, mud and rotting vegetation give off a slightly sweet odor of decay.

To a wading bird traveling from South America, it's a buffet line. The shorebirds feed on seeds, emerging beetles and spiders. With their sensitive bills, they probe the top half-inch of the mud for fly larvae, said USGS biologist Bob Gill, reports the AP.