FRESNO, Calif.—Biologists at Pinnacles National Monument are celebrating the first condor egg laid by a mating pair inside the park boundaries in more than a century.

The egg marks the latest encouraging development in the slow recovery of the endangered flying giants in the regions they historically inhabited. The effort has been hampered by hunters and lead poisoning of the birds.

A female released in 2004 in the Central California park and a male released the same year 30 miles west at Big Sur had been observed engaged in courtship behavior earlier this year, park spokesman Carl Brenner said.

"They are now the proud parents of a small egg," Brenner said.

Biologists confirmed the presence of the egg after hiking to the site on Friday.

In 1982, the last 22 California condors were placed in a captive breeding program. Today, there are 348 in the world, with about 180 flying free at three locations in California and at the Grand Canyon in Arizona. Another dozen are in Baja California.

The goal is to have 450 birds in three distinct populations, with 15 breeding pairs in each group.

"We had a good year last year in Southern California, but it's not universal because we had a number die of lead poisoning in the Pinnacles area and Central Coast," said Michael Woodbridge, a spokesman for the U.S. Fish and Wildlife Service Condor Recovery Program.

One of the dead birds was the mother of a male chick that eventually learned to fly in the wild last April on a ranch outside of Pinnacles National Monument. The chick survived and lives with its father.

Some birds suffer lead poisoning after eating gut piles left by hunters, despite a ban on lead bullets in condor country.

Of the 77 eggs laid in the wild since 2001, 33 lived for at least six months—long enough to fly—with the success rate increasing every year, Woodbridge said.

"That's close to 50 percent, which is probably on par for any species in the wild," Woodbridge said.

Condors, with 10-foot wingspans, generally mate for life. By coincidence the Pinnacles pair with the egg are numerically sequenced—female 317 and male 318 in the population being tracked. It was the first mating attempt by both.

The female was part of the second of six groups of condors released since 2003 at Pinnacles, part of the birds' historic range. The park was attractive to biologists involved in the recovery effort because of the numerous potential nesting sites along craggy cliffs, including the cave being used by Nos. 317 and 318.

It's a two-mile hike over a gain of nearly 1,200 feet in elevation to a viewing site, but the birds "have given us a comfortable place to sit and watch," Brenner said. The viewing area is located across from a bench offering expansive views of the park.

Pinnacles biologists have swapped out the new egg for a wooden one, Fifty-seven days from now—or shortly before the egg is due to hatch—they will replace it with a viable egg produced by condors in captivity.

The swap is standard procedure for most of the Central Coast birds, which sometimes feed on dead sea lions and other pinnepeds that wash up along the Big Sur coast. Those animals, however, often harbor PCBs and the DDT derivative DDE in their blubber. Birds that ingest the chemicals can produce eggs with thin shells.

The real egg produced at Pinnacles will be hatched in a zoo, Brenner said, ensuring an offspring for the pair of condors.

"They are first-time parents, and we don't want them to get discouraged," he said.

Visitors with spotting scopes can see the nesting site from Scout Peak bench on the popular High Peaks Trail.

ps 05/10/10 - Have you actually read all of this? In my 140 page medical entomology final, I inserted a paragraph around page 80 asking if my instructor was still reading my dribble and if he was enjoying his skiing vacation. He gave me an A+. Haha. That's beside the point I want to make... What's up with this wooden egg thing? And then swapping the chick? Haven't they heard of the horror stories of swapped embryos with IVF? I sometimes think we humans like to play God. No good can come from this in the long-term.