EXPERIMENT IN SURVIVAL : YOUNG CONDORS PERCHED ON POINT OF NO RETURN.

Byline: Heather Dewar Knight-Ridder Tribune News Service

On a clear mid-December morning, six California condors will awaken to find the nets that have restrained them have been taken away, and, for the first time in their lives, they are free.

What happens next cannot be foretold.

Will the young condors spread their nine-foot wings, face the warm wind climbing the cliff face and soar over canyon country as their ancestors did 10,000 years ago? Or will the endangered birds retreat to their plywood ``cave,'' unwilling to leave their haven on these red sandstone cliffs?

The long, emotional, controversial struggle to rescue the condor from extinction and return it to the wild has reached a critical point. After 15 years, captive breeding has brought the condor population back from an abyss. But the survivors still depend on humans for their food - and humans are the gravest threat to their existence in the wild.

Now scientists are trying a risky experiment that attempts to radically change the big birds' behavior. Using a kind of aversion therapy borrowed from psychology, they're hoping to kick the condors' eons-long evolution into high gear, rapidly teaching them how to share the land with a booming human population.

``The world their ancestors knew is gone forever,'' said Michael Wallace, curator of conservation at the Los Angeles Zoo and the nation's chief condor scientist. ``We're doing our best to help them adapt to a new world, but we don't have all the answers.''

The great carrion-eaters, North America's largest and most awe-inspiring birds, came perilously close to extinction in the 1980s. Only six wild birds inhabited the mountains of Southern California in 1987, when a mysterious spate of deaths convinced most scientists that the only way to save the species was to capture all the survivors and confine them in zoos for captive breeding.

Since then the zoo-bred population has climbed to 123 birds, but efforts to re-establish a wild population in California's Los Padres National Forest have met with meager success. Many birds have died. Some have had to be recaptured. And of the 20 condors in Los Padres now, none can find their own food without human help.

The Arizona release, now scheduled for Thursday, is the first effort to establish a wild population outside California and the best hope for restoring the condors to a self-sufficient way of life. Ultimately, wildlife managers hope 150 condors will make a home on these remote cliffs of brilliant red sandstone, roaming a sparsely settled territory that stretches 40 miles south to the Grand Canyon and 60 miles north to Zion National Park.

But first biologists have to teach the young birds survival skills that the zoo-bred population has lost, as well as new ways to avoid the threats posed by humans. And to prevent the birds from becoming dependent on people, the human tutors must do their work in secret, staying completely out of sight.

In the Los Angeles and San Diego zoos where the condors are bred, young birds are subjected to a kind of aversion therapy, designed to teach them to avoid two major threats to their survival - people and power lines.

The fledglings are administered low-grade electric shocks whenever they perch on an artificial power pole in their pen. The first humans they see are attackers, who rush shouting into their enclosure, throw nets over them, shove them into cages and lock them up overnight. The lessons are repeated until the highly intelligent birds learn to avoid the threats. It doesn't take long, Wallace said.

``We don't want to harass these guys,'' he said, ``but we don't want them to be garbage birds, feeding on french fries at campsites.''

In the primitive conditions of an Arizona wilderness, that training cannot be fully duplicated. So the birds' handlers are improvising as they go along.

From a camouflaged bird blind 200 yards away from the condors' enclosure, wildlife biologist Mark Vekasy gazed at his charges with the wistfulness of a worried parent. ``These birds are really on their own,'' he said. ``We can't even help them that much. We do what we can, but it's nothing compared to an adult condor can do for them.''

The way of life that Wallace calls ``condor culture'' is learned, not instinctive. Since the last Ice Age, when condors shared the Southwest with mastodons, dire wolves and saber-toothed tigers, the sociable birds have passed down hunting and nesting skills from generation to generation.

In nature, condors lived in groups of about 30, each with its own complicated pecking order. Feeding only on animals that were already dead, they found food not by smell, but by sight and intelligence: soaring at heights of 6,000 feet or more, they scanned the landscape for clumps of ravens, vultures or coyotes gathering at a carcass, then swooped in en masse and took over.

They mated for life, rearing only one chick every two years. The chicks learned how to socialize, hunt and pair off by watching adolescent birds who formed a pack, like a kind of avian 4-H Club.

But human settlement threw the inquisitive condors' way of life into turmoil. Humans shot and killed many; others died of lead poisoning from the bullets they found in animal carcasses, or of eating poison baits set out for livestock raiders like coyotes. Collisions with power lines killed a handful, and at least one died after drinking from a puddle of antifreeze.

When wildlife biologists removed the last birds from the wild, ``I really lamented that we had to do this, because I knew we were breaking the chain of condor experience out there in the wild, and we'd have to start from scratch,'' Wallace said.

In captivity, the scientists hide from the hatchlings behind one-way glass. They use giant condor puppets to handle the birds and feed them as their parents would on rat carcasses.

Once the young birds are old enough to go into fenced and net-covered outdoor pens, their human caretakers hide behind plywood screens and leave food in the pens under cover of darkness. Here, too, the birds are conditioned not to sit on power poles and are subjected to mock attacks.

By the time they're five to six months old, the young condors weigh 15 to 20 pounds, have wingspans of eight feet or greater, and are on the verge of flying. Most will remain in captivity, but a few are destined for release in the Southern California forest.

The 5- to 6-month-old birds now perched on a 6,000-foot Arizona cliff were brought here in October. Since then they've been tended by a team of biologists from The Peregrine Fund, a Boise, Idaho conservation group working with the zoos, the federal government and state agencies.

The biologists live and work in a tent atop the cliffs, more than 20 miles from the nearest tiny townlet and a quarter-mile from the condors' alcove of red sand and juniper trees. A winding, carefully camouflaged trail leads to a trio of observation blinds - dun-colored plywood boxes, with tiny openings further concealed by aromatic branches of sagebrush.

The scientists speak in whispers within earshot of the jet-black birds. They take careful notes as the young condors, already nearly full-grown size, stretch enormous wings to catch the cliffside breeze or lazily groom themselves in the sun. Every other night while the fledglings are asleep, their keepers hide behind sheets of plywood to sneak into the 20-by-40 foot flight pen and drop off the carcass of a stillborn calf, a donation from a local dairy.

The scientists will continue setting out food for the young birds after their release, gradually moving the calf carcasses farther away from home base. If all goes well, within a year the condors will be crossing the desolate valley below to feed on the nearby Kaibab Plateau, a thickly forested limestone ridge that is home to fat mule deer. Once there, experts hope the big birds will begin to discover deer carcasses and other natural prey, gradually weaning themselves from human-supplied food.

It's an optimistic scenario, and even if it works the birds' survival is far from certain. The Kaibab Plateau is one of Arizona's most popular hunting spots, and scientists don't yet know how to reduce the birds' risk of lead poisoning from hunters' bullets.

Even if they avoid that peril, no one knows whether there's enough game in the area to feed the great birds. After all, the mastodon and dire wolf vanished 10,000 years ago, and only a handful of buffalo remain. If the land can support condors, some scientists wonder, why aren't they living there already?

Underlying these practical questions are even tougher philosophical ones:

What does it mean to ``save'' a species? Is it enough to preserve a few of each kind in a zoo, a wilderness preserve or some other modern ark? Or is that kind of conservation simply a sop to humankind's conscience? And if saving a species means saving its wildness as well, do we humans understand other creatures well enough to do that?

People working on condor conservation have vehemently argued those points for more than a decade. For the time being, they've uneasily settled on this reply:

``Temporarily reducing the condor to a mere creature of captivity is still better than having a dignified but dead condor,'' wrote biologist Lloyd Kiff in 1990. ``The condor going back into the wild will be the offspring of environmental tinkering, but it will be no less a condor.''

Even some members of the condor recovery team have doubts about the path they've chosen, Wallace said.

``There are people who bite their nails and say, gee, do we really have to be this invasive with our conditioning of the birds?'' Wallace said. ``There are people who ask, how can you justify putting birds out into the same damaged environment that endangered their ancestors in the first place?

``Well, what's the alternative? Condors in theme parks?

``People want to see condors flying wild and unchanged as they did in prehistoric times. That environment is gone. We have to produce a new kind of condor, a condor that's going to survive in a human-dominated environment.

``I think they can do it. I know they can do it. It just may take them some time.''

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Photo

Photo: Young California condors get used to their Arizona surroundings in a netted cage, which biologists will remove soon to free the birds.

Knight-Ridder Tribune