They came bearing a warning: The wild birds that the Yup’ik have hunted for millenniums may be carrying the first traces of the deadly bird flu virus from Asia into North America. “It’s kind of scary, you know,” said resident Ronnie Peter, 39. “That’s like, our food, you know.’’

The H5N1 avian influenza emerged in China 10 years ago and has since spread into Europe, Africa and the Middle East. While the virus mainly infects fowl, since 2003 it has sickened 256 people and killed 151 around the world.

Kipnuk lies at the crossroads of an invisible freeway system linking migratory birds that journey along the East Asia-Australia flyway with those from the Pacific Americas flyway. Millions of birds flock every year to this seemingly endless expanse of soggy land in the Yukon Delta National Wildlife Refuge to feast on insects, grasses, worms and mussels before heading back south in the winter to Asia, Australia and other parts of the Americas.

“If it’s going to show up in wild birds, Alaska is the most likely place where it’s going to happen,’’ said Brian McCaffery, a biologist who was camped a few miles from Kipnuk collecting bar-tailed godwit droppings for testing. Federal officials have identified 29 bird species most likely to carry the deadly virus from Asia, and they have enlisted local hunters to help provide birds for testing.

“Oh Lord, what are we going to eat? Store-bought food?’’ thought Steven Mann, who oversees tribal operations in town. The nervousness has waned through the summer, said the 58-year-old ex-Army sergeant, but still, “We don’t joke about what we eat here.’’ Mann’s son, Danny, a lanky 27-year-old who used to work as a bilingual parent liaison for the school, took on the job of bird-flu testing in Kipnuk for the tribal health agency. He gets $15 for every bird he samples.

At the tribal council offices, he was on the phone, checking in with hunters. “Got any birds?’’ he asked Ronnie Peter, who goes hunting just about every day except Sunday. “How many?’’ Danny Mann asked. “Can I come over and check them?’’

Mann climbed up the steps to Peter’s porch and dug into a pile of common eiders, pintail ducks, a shoveler and a Canada goose. He snapped on a pair of surgical gloves and started filling out a form on the birds. He inserted it into an eider through its cloaca. Mann put the swab, now covered in a greenish-white goop, into a vial.

Mann repeated the procedure for the other birds. He headed back to his mother’s house, where he crept under the front staircase and lifted the lid of a white canister filled with liquid nitrogen. As cold white vapours curled out, he dropped in his handful of vials, which he would send away for analysis.

Mann said he swabbed as many as 300 birds in the first round of sampling in May. In September, he collected samples on about 50 birds. To get more hunters involved, the health agency raffled off a 55-gallon drum of gasoline for each round of testing. Villagers got one raffle ticket for each bird they turned in.

So far, government inspectors have taken 18,000 samples from birds all over Alaska. They have found no bird flu. Still, Mann said, there are so many birds from so many places that pass through this forbidding terrain that detecting the virus is “not a matter of if, but when.’’

—Jia-Rui Chong / (Los Angeles Times)