WASHINGTON — Not since Shrimpy the kelp gull blew in to Maryland from South America in the 1990s has this region played host to such a rare, well-traveled and positively unusual species as Jim Swarr.

The retired ophthalmologist from St. Petersburg, Fla., joined fellow birders from South Carolina, Pennsylvania, West Virginia and the region in the muck of a Frederick County cornfield, about 50 miles northwest of Washington, hoping for a glimpse of the northern lapwing.

The bird, whose wing feathers glow with a metallic sheen, usually winters in East Asia but was seen for the first time in Maryland this week, pulling worms from a puddle of melted snow. It may have lost its way while flying south from its Northern European home or been blown off course by high winds. Either way, its appearance, news of which spread through the Internet, provides dedicated birders such as Swarr with one of the biggest thrills of their sport.

"This is an exciting bird, a vagrant Code 4, very unusual for North America," Swarr said, consulting one of six bird guides he carries in his Honda minivan. The guide lists V(4) birds as having been spotted only a few times in North America over the past three decades.

THE WASHINGTON POST Jim Swarr, a Florida retiree, scans the skies for the elusive northern lapwing, which usually winters in East Asia but was seen this week for the first time in Maryland.

Swarr is a full-time "chaser," a birder who will go anywhere, at any time, to add a species to his "life list," a record describing in obsessive detail each new bird and the time, place and conditions under which it was sighted.

Since last summer, Swarr has clocked 51,000 miles in his Honda, building his life list to 660 species and, like many birders, spending thousands of dollars pursuing his sole leisure activity with money he has saved. "It's addictive," he said.

He has walked along a two-mile seawall off the coast of Vancouver to visit a pair of McKay's buntings gone astray from Alaska. He has driven cross-country to California to list a Nutting's flycatcher. He has stood in sweltering Texas heat for a glimpse of a roadside hawk, rare in those parts. And he has stood with thousands of others near a tiny airstrip on Martha's Vineyard, watching, through $1,500 binoculars, a red-footed falcon sitting on a traffic sign.

This day, Swarr explained with narrow-eyed seriousness, is not going to be the day he "dips," or fails to spot his quarry. "I always get my bird," he said.

He took his position Wednesday with 10 other die-hards in a ditch, bracing against a chilly wind rich with the scent of damp cornstalk. There, smoking a long and aromatic pipe, was F. Glenn Smith, a retired divorce lawyer from Columbia, S.C., with 702 birds on his life list, including a couple from the island of Attu, Alaska, where he had gone "to see what blew in from China, Japan and Russia."

There was Chuck Berthoud of Hershey, one of a delegation of Pennsylvanians who were "shut out" on Super Bowl Sunday, not because the Philadelphia Eagles lost in football, but because they had missed the redwing sighting in Bucks County, Pa. "We're really wound up now," he said.

And there was John Fox, a patent examiner from Arlington, Va., a self-described piker who said he became interested a couple of years ago when he looked out at his bird feeder and thought, "What the hell are those?" But the lapwing, he said, "is one of my dream birds."

The northern lapwing winters in Asia Minor, the Indian subcontinent and Southeast Asia. About as large as a crow, it has a black and white face, a majestic black crest and near-iridescent wings of green, black and bronze. Its cry sounds like "chee peewi ... peet ... air willucho weep weep ee yo weep," according to the Sibley Guide to Birds.

The sound of the birders was louder as they compared notes, seeming to peer through binoculars only rarely. Fox, outclassed, gathered his camera gear to get into his car. "I'm a jinx," he said, and headed off to try his luck in another spot.

An hour passed, the remaining birders saw nothing, and some gave up. Not Swarr. "Come on," he said, piling into the Honda for a trip around rural Thurmont, in northern Frederick County. The back end was stuffed with clothing, bedding, nine maps and the six bird guides. Swarr peered out the top eighth of his windshield, scanning the skies.

"Ah!" he said, training his Swarovskis on a treetop. A kestrel. Then robins, Canada geese and a single turkey vulture. Hardly life-list material.

Passing farmhouses and cows, he faced the prospect of dipping. "Hmmm," he said. "Maybe not today."

Swarr would have to wait. But at that moment, on Blacks Mill Road, John Fox the dabbler, wild-haired and windblown, was emitting the cry of the victorious.

"Got him! Got him!" Fox shouted, beaming from the ditch. "Caught him flying!"