Mark Obmascik needed a change. The Denver Post reporter had spent too much time with death and disaster. He'd been lead writer on the Columbine High School massacre, a series that won the Pulitzer Prize. He'd covered the Texas Seven jailbreak and the devastating Colorado wildfires. "It was one gruesome story after another," he says. "I wanted to write something my kids could read. I wanted a break."

Trolling for something lighter and a lot more fun, he contacted the American Birding Association. Obmascik, who received the 2003 National Press Club Award for environmental news coverage, had written about birders before, knew of their sometimes-quirky nature.

He soon found himself enthralled by master birder Sandy Komito, embodiment of an odd competitive birding subculture.

Obmascik knew a good story when confronted with it, identified it as easily as Komito could identify a Nutting's flycatcher.

He had his subject, obsession. He'd write a book about extreme birders (primarily men) who give up a year of their life to crisscross North America on a moment's notice simply to compile the longest list of sighted species. Ptamigans in Colorado, hummingbirds in the Arizona desert, owls in Minnesota and boobies in South Florida.

In the birding community, it's called the North American Big Year. It begins before sunrise on Jan. 1 of each year. And 1998, for a convergence of reasons, was a remarkable year.

An amazing 745 species were sighted by the top birder, a record many experts say may never be broken.

Among the crazed contenders were 1987 winner Komito, a bass-voiced New Jersey industrial contractor and legendary storyteller; Al Levantin, a chemist and retired Fortune 500 executive from Aspen with "40 years of repressed obsession"; and Greg Miller, a 5-foot-7, 225-pound nuclear power plant computer contractor from Maryland who was pining over his recent divorce, but who, Obmascik notes, "got more hugs per mile than any man I've ever met."

This unlikely mix of characters had only one thing in common: "a consuming passion, birds."

For that, they endured danger, exhaustion, sickness, and in the case of Miller, mounting debt.

"They were like grown-up Tom Sawyers, gallivanting around the globe chasing creatures that have a brain no larger than your belly button," says Obmascik, who was in South Florida recently to promote the resulting book, The Big Year, A Tale of Man, Nature, and Fowl Obsession, (Free Press, $25).

Obmascik never witnessed a single day of the grueling 1998 competition, having begun the book well after the year ended. But through interviews and fieldwork and compelling storytelling ability, he has imbued the tale with a riveting immediacy.

Besides re-creating the intense rivalry of the obsessive, breakneck chase and the hardships encountered, he intersperses in the pages a fascinating mix of bird science and birding history.

There are 675 homies, or homegrown birds, in North America, he notes, birds that either live here or migrate through. The additional 70 birds that made for the '98 record "were all birds blown off course by the strongest El Niño on record, or just birds that got lost. These birds are reported on the Internet and through rare bird alerts."

Extreme birders pay to be alerted by pager or phone. Hundreds if not thousands of people in North America, says Obmascik, drop everything when an alert comes in.

Obmascik's competitors were no exception. "They were," he says, "away from home for 270 days, they traveled 270,000 miles, they lived for weeks on end on a desolate Alaskan isle [Attu] that is 1,700 miles from Anchorage and 200 miles from Siberia. And they stayed and waited for ... El Niño ... to blow Asiatic birds into North American air space just so they could count them."

That icy destination paid off in an avalanche of numbers.

In their feverish pursuit, the trio stood in sleet and rain, helicoptered into cloud-shrouded mountains, slogged through swamps, muck and landfills, the latter whose stench could make grown men swoon, and they suffered sleeplessness, seasickness, loneliness and hunger, just to see a bird.

While their paths sometimes crossed, and they'd find themselves uncomfortably sharing the same boat, the same mountaintop or island, they were pitted in a heady, solo competition.