TWENTY years ago, in a cliff-top cave near Los Angeles, a condor chick pecked his way out of his egg. As he broke away the rest of the shell and his mother nuzzled him, neither could have had any idea that their species was nearly extinct, and that in just a few months鈥� time they and the remaining 25 members of their kind would be heading for protective captivity.
The 1980s were a dark time for the California condor. Its numbers were in free fall from the effects of human encroachment, forcing ecologists to revise their initial plan to try to maintain a population in the wild. So in 1984, the US Fish and Wildlife Service petitioned the California Department of Fish and Game for permission to bring in the remaining condors for a breeding programme. Critics fiercely attacked the move, arguing that the birds would lose their 鈥渨ildness鈥� forever. But it was considered the only way to save the California condor. By 1987, the last free-flying condor had been captured and taken to the San Diego Wild Animal Park which, along with Los Angeles Zoo, would run the programme.
The decision appears to have been the right one, as there are now more than 200 condors. Half of them live in the wild, and this spring some of these even bred. It looks like conservationists have succeeded in doing what many said was impossible 鈥� they have saved the California condor.
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Or have they? From a genetic standpoint, at least, the recovery programme has been hugely successful, producing a gene pool that is as diverse as possible, given the starting population of only 27 birds. But, like many animals, a condor鈥檚 essence is not just in its genes but in behaviours passed down the generations from older and more experienced birds to juveniles. This 鈥渃ondor culture鈥� is far more nebulous than their genes, and harder to preserve. It is also crucial if the bird is to survive in the wild. If the project has taught conservationists one thing, it鈥檚 that captive animals cannot be truly wild again unless they retain their learned customs as well as their genetically programmed behaviour.
The project workers were mindful of this from the outset. 鈥淕enetics were only part of the conservation challenge,鈥� says recovery coordinator Bruce Palmer. 鈥淭hese birds are very social and intelligent. If you watch them interact, you can see them studying and learning from each other all the time.鈥� While in captivity, the aim was to encourage this flow of information between the birds, but at the same time prevent them from learning new tricks from their captors. 鈥淲e could not have the birds interacting with humans and studying our behaviour if we wanted them to stand a chance of becoming wild again,鈥� says team leader Mike Wallace from the Zoological Society of San Diego.
Model parents
Having no interaction with humans created complications, though, especially at the start. California condors lay only one egg a year, but Wallace knew from his experience recovering Andean condors in Peru that if they took away the first egg and incubated it artificially, the parents would probably lay another one soon after and act as though nothing had happened. The problem was how to hand-rear that first chick without any human contact.
The trick was to use hand puppets resembling the heads of condor parents. These didn鈥檛 just feed the chicks, they also served a psychological purpose. 鈥淭he puppets gave the young birds an adult condor image to focus on,鈥� says veteran condor puppeteer Mike Clark. And as the chicks grew they were denied any opportunity to watch people. For a short time at the start of the project, the chicks were even exposed to adverse conditioning, where keepers would come in and harass them, but this was stopped because of concerns for the safety of the birds 鈥� and the keepers.
With many parents producing two chicks a year, the numbers grew steadily, and by 1992 the team felt it was time to try some releases. The results were not good. Of the two birds initially freed, the first died after swallowing antifreeze and the other had to be recaptured because it kept dicing with death by landing on power poles and pylons.
Undaunted by their initial failure, the team released six more birds in late 1992, all raised in captivity. Three died in collisions with power lines and the rest were brought back to the zoo because their habit of landing on pylons was considered too risky. Towards the end of 1993, more birds were released, this time in areas far away from any poles or pylons. But it made no difference: they eventually found their way back to civilisation and, again, those that didn鈥檛 die from electrocution had to be recaptured.
鈥淲e realised that we were going to have to rethink what we were doing,鈥� says team member Greg Austin. 鈥淚t really was an excessively high mortality rate.鈥� Zero interaction may have been a good way to keep captive condors as true to their natural state as possible, but the birds obviously didn鈥檛 possess all the knowledge they needed to survive in the wild, in an environment that was now very different from the one in which they had evolved. Their captors would have to do something about it.
鈥淥ur main problem was the power poles,鈥� says Wallace. 鈥淪o we decided to try and teach our birds to stay away from them.鈥� In 1994 the researchers installed wooden cross-beam power poles in the enclosures. They positioned them quite high up, so that the condors would see them as desirable perches, then rigged them to give any bird landing on them a mild electric shock. 鈥淲e were really saying, 鈥楥ome on guys, we dare ya to give it a try鈥�,鈥� says Austin. 鈥淚t was a lesson they needed to learn.鈥�
The place not to be
Wallace recalls how some of the adult birds touched the poles up to 10 times before the message sank in. But many never went near them. 鈥淚鈥檓 not sure if some of them could see the electromagnetic waves or if they were being told by others that power poles are unpleasant to sit on.鈥� But the training must have worked, since of the 28 birds released over the next two years, not one died from power cable collisions or electrocution.
The success of this aversion therapy, however, served to highlight another problem of putting captive-bred birds into the wild. At this stage the recovery team was releasing primarily young birds raised using the hand puppets, because there were very few parent-reared youngsters and the researchers needed to keep the original wild population for breeding. The trouble was, when these juveniles got together in the wild, they were not behaving properly. Rather than fly around looking for carrion, many preferred to investigate centres of human habitation. They would congregate around oil pumps and play with bits of garbage, or chew on the roof tiles of houses. 鈥淲e were putting teenagers together without adult supervision,鈥� says Wallace, 鈥渁nd they were behaving like a bunch of hooligans.鈥�
The youngsters obviously needed some discipline. And that meant changing the way they were brought up. After watching videos of condors feeding their young, the puppeteers learned to be tougher parents. Chicks were no longer allowed to push the parent puppet around but instead were forced to behave more submissively, as they do with real parents.
Once weaned, small groups of youngsters would be placed in a large enclosure with a 鈥渕entor鈥�, an older bird that ideally was once wild. 鈥淭he mentors quickly put a lot of the young ones in their place,鈥� recalls Palmer. When juveniles flew onto the best perches they would get swatted away by their elders. And when feeding, the mentors would make the younger birds wait until they鈥檇 had their fill. It was essentially a course in condor etiquette.
This social training worked wonders. Birds that had been through the programme started acting more like adult condors when released. In fact, the researchers were so pleased with the mentoring that they decided to extend it, to see whether having a mentor in the wild would encourage captive-bred birds to start using traditional nesting sites, watering holes and feeding grounds. It was a gamble because it would mean releasing one of the nine remaining original wild condors responsible for the genetic diversity of the population, and there was no guarantee that it would remember its old haunts and habits, let alone pass the knowledge on to the next generation.
In the end, the team chose a bird called AC-8, or Adult Condor-8. She had produced more than her fair share of chicks during the early years of the breeding programme but had suddenly stopped laying eggs, probably because of her age. Letting her go would therefore make no difference to the population鈥檚 gene pool.
So, on 28 March 2000, after 14 years in captivity, AC-8 took to the skies above her old home territory in southern California. She integrated seamlessly into the new condor community there, and the researchers believe she started teaching them some of her old tricks. Within months, new movements of the birds led the team to suspect that condors were flying to watering holes and using roosting sites that had not been visited since before the captive breeding began. 鈥淪he was giving them something we could not,鈥� says Palmer. 鈥淪he was keeping condor traditions alive.鈥�
AC-8鈥檚 release was so beneficial that the researchers decided to return another original bird to the wild, and on 1 May 2002 the last wild condor captured, AC-9, was given his liberty. The knowledge of these veterans has been invaluable in establishing a new California condor community in southern California. But there are still problems. For example, lead poisoning from ingesting bullets has been a major cause of death since the releases began and the birds seem unable to learn from each other to avoid prey that has been shot. The recovery team now drops stillborn calf carcasses in the middle of the night to try to persuade the birds to eat only in one area where there is no risk of consuming lead shot with their dinner. This is proving difficult because the birds prefer the carrion they find themselves.
That aside, this spring there was a major breakthrough in the conservation efforts with the birth of the first wild California condor chick for more than 20 years. The chick is the first of three so far and was born to a pair of condors that had been part of a trio the year before. While courting two females, the male had been unable to spend enough time with either to reproduce, so one of them had to be removed from the wild. 鈥淲ith so few mature males in the wild, there are a lot of distractions,鈥� says Palmer. No such measures were necessary with the other new parents, however. What鈥檚 more, all three chicks have survived the hazards of early condor life and are now the size of turkeys.
Able to cope
But there is still a long way to go. To pull the condor off the endangered species list the recovery team must establish two stable wild populations of 150 birds each and maintain a captive population of 150. They are optimistic though. 鈥淔our hundred and fifty birds by 2020? We can do it,鈥� says Wallace.
No one in the project is under the impression, however, that things will one day be as they were. Palmer points out that any species that falls in number as drastically as the California condor is bound to lose genetic variability, and that may limit its ability to deal with changing conditions. That鈥檚 bad news because as humans encroach on condor territory, the biggest threat to their survival is the changing environment. But these are intelligent birds and Palmer is convinced they can learn to cope. 鈥淎 new condor community consciousness will arise for the new, people-shaped, world they now live in,鈥� he says.
Meanwhile, the conservationists also continue to learn. And the insights they gain may prove crucial to the survival of the many other animals being squeezed out of their natural habitats by humans. 鈥淎ll major vertebrates will need to be managed if they are to survive [modern human activities] 鈥� even if that management is just staying away and giving them breathing space,鈥� says Wallace.
The California condor project shows that even animals on the brink of extinction can be returned to the wild. It also highlights the fact that human activities change the natural world irrevocably. 鈥淲e will never see the wild condor behaviour that existed before our cities appeared,鈥� says Wallace. 鈥淲e have created a new landscape 鈥� but that needn鈥檛 be a landscape without condors.鈥�
