Dawn in Tucson: Outside a suburban home, two men, binoculars slung around their necks, step out of a rented Ford Pinto. They hestitate for a moment, squinting. Should they unpack their camera? In the lore of their field such presumption might spoil their luck.

But they are two of the premier bird watchers in the country -- Paul DuMont and Paul Sykes -- and novices' superstitions are not for them; cavalierly they unpack the camera anyway.

In the dim October light they seem an unlikely pair. DuMont, 41, is a publications editor with the Soil Conservation Service in Washington. He says he's seen more species of U.S. birds -- 122 -- than anyone else in the country. His close friend and competitor, Sykes, also 41 is a biologist with the U.S. Fish and Wildlife Service in Delray Beach, Fla., and he is only one bird behind DuMont.

Both have been bird watching for three decades, and both are missing from their life-long checklists the scarlet-headed oriole a long-beaked Mexican stray. They've come to Tucson -- at considerable expense -- to see the oriole, to gain another merit badge in pursuit of the avian obsession.

"There are 654 species of birds considered nesters or migrants that can be reliably counted on to be seen. That leaves 46 birds occasional," DuMont explains. The rest are rarer still and are called accidentals. They are birds that have strayed from other parts of the hemisphere into the extremes of this country where, says DuMont, he and Sykes now have to go: Florida, Southern Texas, California, Alaska, Southeastern Arizona.

But, unlike arch-rival Joseph Taylor from Honeoye Falls, F.Y. -- who flew from Kenya to Massachusetts to see the rare Ross' gull, and then right back to his safari in Kenya -- DuMont and Sykes aren't quite prepared to go to any lengths to see a bird. For one thing, they're not independently wealthy and work schedules aren't always malleable.

On the other hand like fellow bird watchers and former cabinet members James Schlesinger an Elliot Richardson, they have far surpassed the mild interest of illustrious birders of the past -- from Pliny the Elder to Frederick the Great to the young Winston Churchill.

Robert Arbib, editor of the National Audubon Society's publication, estimates the number of true American birders -- people who go bird watching by themselves -- at about a million, although the U.S. government puts the figure 10 times higher.

Arbib says the number of birders in the "600 club," (600 species of North American birds seen) is a mere 150. No more than 10 U.S. birders have seen more than 700 species of U.S. birds.

This elite group comprises the bird watcher's grapevine responsible for alerting DuMont and Sykes to the oriole in Tucson.

Scarlet-headed orioles, rare this far north of the border drew DuMont and Sykes to Tucson three years ago. But by the time the two men arrived, the birds had been eaten. A Cooper's hawk had gotten to them first. For both DuMont and Sykes, trips like this are not simple. "I have a wife, three kids and a mortgage," Sykes said, so when he does flit cross-country it's usually for a sure bird. home of Gale Monson, a long time home of Gale Monson, a long-time friend who is out of town. His wife Sally who is only thankful her orioles aren't as rare as the crowd-drawing Ross' gull, ushers the two men in and right away points them to the kitchen and study windows, which act as one-way mirrors to reflect the sun's heat.

A yellow and red plastic hunningbird feeder swings from a tree 10 feet beyong the reflecta-shield glass. The birds either go to the feeder, Monson says, or to the birdbath, and because of the special glass they can't see in through the windows. Sometimes it's only the male. Other times it's one of the two females.

This is only the sixth time scarlet-headed orioles have been sighted in Arizona. Their home turf is 370 air miles south of Tucson. No one knows how they got here or how long they'll stay.

Asking her guest about mutual friends, Monson ticks names of other birders who've come to Tucson to see the orioles. Jim Vardaman, the Mississippi lumberman who's trying to se 700 species in a single yearar (he's only 10 short, but Sykes and DuMont don't think he'll make it; the Indianan who spent the night outside the Monsons' in his rented car; a man from Oklahoma, another from Michigan; and myriad local birders.

Outside, only Anna's hummingbirds fly around the feeder. DuMont and Sykes talk and watch anyway. Then, they stop talking, simultaneously. An oriole has come in.

"Look at all that white in the wing." Sykes adjust his binoculars. "the streaks are broken. They look like spots." DuMont moves back to get a better view. "How nice." Pause. Then a handshake. The orange, black and white oriole is gone.

There are no shouts, no slaps on the back, nothing to indicate excitment or even relief. Instead, once the male bird has fled, DuMont and Sykes get down to the nitty-gritty -- How odd the black and white streaking on the back was, how the beak was down-curved instead of straight, how they're sorry H. Granville Smith, a 693-count birder, didn't make it in time -- until the door bell rings.

It's H. Granville Smith. Up from Green Valley, a retirement settlement just south of Tucson, he doesn't know DuMont and Sykes have flown into town. They surprise him, with a greeting far more effusive than their emotionless reaction to the oriole.

Maybe, though, that's because they know the bird will reappear. It has to.

H. Granville didn't see it the first time.

Sure enough, the male zips in again.

He lights on a branch and moves to the feeder. He clutches the base, wraps his body around it and starts sucking sugar water from one of the yellow flowers. He stops ever now and then, in his split second appearance, to look, flashing his dark eye-bar and hiding his deep orange (not scarlet) cap. Then, he skitters off.

H. Granville, much more pleased than DuMont or Sykes, is excited. Pulling out his bird books, he begins comparing the books' drawing to the actual bird. He finds the orange on the bird much brighter than the orange in the book. And then, there's the cap -- which isn't scarlet.

That's a topic for new debate, and the three birders are off. Now all of a sudden, they seem eccentric. And now, in the light of day, they look vaguely possessed.