California Condor Found Dead Near Pyramid Lake : Wildlife: The bird was one of two released to the wild in January. It appeared healthy and had not been injured so a toxicology test has been requested.

One of the first two California condors to be released to the wild has died, dealing a stunning blow to biologists who are working to save the species from extinction.

The death of 15-month-old Chocuyens (Cho-KOO-yenz) has left 17-month-old Xewe (GAY-wee) to fly alone, and has saddened and mystified biologists who recovered his carcass Thursday from a rocky ledge near Pyramid Lake Dam.

A necropsy at the San Diego Zoo found that Chocuyens was apparently healthy and showed no signs of injury, but tissue samples have been sent to the Patuxent Wildlife Research Center in Laurel, Md., for toxicology testing.

“If it was a healthy bird and died that abruptly, you’d expect to find some physical evidence,” said Robert Mesta, condor program coordinator for the U.S. Fish & Wildlife Service.

“They didn’t find anything,” he said. “The X-rays didn’t reveal any broken bones, there was no brain damage like it had suffered a concussion. . . . I was told it looked like a very healthy bird.”

Chocuyens’ death has forced the condor biologists to change their plans.

Last week, they trapped No. 38 and No. 39, two Andean condors that had been released with Chocuyens and Xewe to act as mentors in the wild.

Chocuyens and Xewe then were to have taken the role of elder guides for six more 6-month-old California condors scheduled for release in December.

Now, the biologists must re-release No. 38 and No. 39 to keep Xewe company until the other California condors arrive, Mesta said.

“Having a single Californian out there makes us nervous,” he said. “They’re not a solitary species, they’re very gregarious.”

The news of Chocuyens’ death hit hard.

“I didn’t cry last night till I was alone,” said biologist David Clendenen. “You spend so much of your life working with them and trying to keep them healthy, and something like this happens. It’s devastating.”

Before the last wild condor, AC-9, was captured in 1987, the birds had been dying from gunshots, lead poisoning from shotgun pellets in carcasses they fed upon, collision with high tension wires and shrinkage of their habitat. By 1987, their numbers had dwindled from thousands to 27.

That year, biologists captured the remaining birds and began the breeding program at the Los Angeles Zoo and San Diego Wild Animal Park.

Clendenen had helped trap AC-9 and added it to the breeding program, which has increased the number of captive California condors from 27 to more than 50.

And he had ushered AC-9’s daughter Xewe and Chocuyens from the hands of their San Diego caretakers in October, 1991, to a lofty site in the Sespe Wilderness in Ventura County. The two were released there in January.

“I talked to an old friend who was a veterinarian on the project and moved to Melbourne,” Clendenen said Friday. “I talked to her on the phone and I broke down at that point. We cried together.”

On Thursday, he helped retrieve the carcass of the giant bird, which had grown to 20 pounds and had a wing span of more than 8 feet.

Biologists had monitored daily, by lens and radio, the only two wild California condors. They had fitted them with radio transmitters on both wings, one battery-powered and the other a solar-powered backup, Mesta said.

Chocuyens’ signal showed he had not moved since Tuesday.

Late Wednesday afternoon, field biologist Dan Peterson spotted him through a high-powered scope about 500 meters away, face down on a ledge where the two condors had habitually roosted in the past, Clendenen said.

At dawn Thursday, the biologists strapped on cameras, slung ropes over their shoulders and picked their way across the 400-foot-high cliff face to the roost.

They found no clues at all to his death, Clendenen said.

They slipped the carcass into a nylon sack, hauled it back to the cliff top, packed it in ice and drove it to the San Diego Zoo.

There, zoo pathologist Marilyn Anderson spent three hours on a “cosmetic necropsy,” examining the carcass but leaving it pristine enough to preserve and mount for later study, said zoo spokesman Jeff Jouett.

Jouett said that Anderson found none of the lead shotgun pellets that have poisoned condors in the past, no intestinal blockages that could have starved Chocuyens to death, no splinter of evidence on which to hang a theory.

“I think that we expected birds to die through the whole thing,” Clendenen said. “It’s hard to take when it happens, but it’s just part of the game. We’re going to keep marching on and hopefully, if we can find out what killed the bird, we can negate that in the future.”

Results from the Maryland toxicology tests should arrive in a few days, Mesta said.

“We’re just really perplexed at this point,” Mesta said. “It was a shock, it really was. We didn’t expect it, and we’re really anxious to find out what happened.”