Podcast: The California condors are back from extinction, but still endangered:

The California condor perched in a tree at Pinnacles National Monument is anything but a pretty creature. Its bald pink head, uniform black plumage, and vulture-like profile cause more disdain than awe. It makes one wonder why conservationists invested so much money and effort into saving this scavenger from extinction in the 1980s. But suddenly the condor opens its wings, with a span double that of a man's arms, its primary feathers sticking out like fingers. As it soars the sky, the answer comes naturally: This bird is an icon of North America's wilderness.

"The condor is the poster child of all endangered wild species," says toxicologist Donald Smith of the University of California, Santa Cruz. But its recovery is far from perfect. Smith's team recently showed that the lead poisoning killing some condors comes from bullets the birds ingest when eating the carcasses of hunted animals. Lead poisoning is the main ongoing threat, but the released condors also collide with power lines, feed trash to their chicks, and grow too comfortable with humans. Ecologists are now debating how to adapt the program so condors will thrive for decades to come.


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The condors at Pinnacles, near Hollister, California, will soon face these dangers. Five juvenile birds rest peacefully inside a flight pen on the top of a hill. They arrived a few weeks ago from the World Center for Birds of Prey in Boise, Idaho. The biologists will keep them in the isolated facility with an adult mentor for a few months to get them used to their future habitat. Neither the juveniles nor their mentor pay attention to the four wild-flying condors eyeing them from outside.

"They came to check out the new kids on the block," says Court VanTassell, field supervisor of the Pinnacles program. VanTassell, like others in the recovery program, declares himself fascinated with condors. "The condors are so unique and intelligent. They're similar to primates," he says. This enthrallment helps him bear not-so-glamorous work days up to his elbows in calf carcasses, which biologists feed to the condors. "Really, you end up losing your sense of smell in this program, just out of survival."

On the verge of extinction

Thanks to the efforts of people like VanTassell, the condor population has risen from a low of 22 birds in 1982 to 279 in March 2007—with 151 in captivity and 128 flying free in California, Arizona, and Baja California, Mexico. Condors first made the endangered species list when about 50 birds remained in 1967, before the Endangered Species Act was formally passed by the U.S. Congress.

Not until 1978 did a national panel convene to study the condor's fate. The panel—including members from the American Ornithologists Union, the National Audubon Society, the California Department of Fish and Game, and the U.S. Fish and Wildlife Servicerecommended captive breeding, gradual release to the wild, and a more aggressive research and conservation program. The report called for radio transmitters to keep track of wild-flying condors and intensive field work to manage them. That spawned the recovery program in January 1980.

Initially, the program was polemic. Environmental groups such as Friends of the Earth and the California chapter of the Sierra Club were against "hands-on" management of the condors. These ecologists advocated letting the condor die free rather than keeping it under "house arrest."

"People used to say the condors were Pleistocene relics," says Brian Walton, coordinator of the Santa Cruz Predatory Bird Research Group and former participant in the recovery program. "But all birds are Pleistocene relics, so there is no reason to let any bird go extinct." With help from a cousin of the California condor, the even-larger Andean condor, the number of free-flying condors started to grow steadily after 1992 when the first captive-bred condors were released. Most opposition to the program subsided.

Its success surprises Walton. He recalls that in the 1980s he took his 2-year-old son to southern California to see the last remaining free-flying birds. "I held him up in the air so he could see them and see what they looked like, because I wanted to be able to tell him that he had actually seen a condor before they went extinct," Walton says.

One of the program's strengths is producing new chicks. Biologists learned how to induce condors to breed annually rather than every other year, their natural rate. They also doubled birth rates by removing the first egg the females laid, which made them produce a second one. The first egg was then incubated; the resulting chick was reared either by human caretakers (using condor puppets to feed the baby birds) or by real condor parents.

Dangerous liaisons

Despite the success of captive breeding, condors face hazards as soon as they fly into the wilderness. Most notably, Walton thinks biologists release the birds too late, when they have lost their wild instincts and have grown too used to humans. Walton's own group breeds and releases falcons and eagles as soon as those predatory birds fledge the nest. They have never had a juvenile falcon or eagle seek human contact. But this problem plagues condors, which stay in captivity up to 11 months longer.

"It's hard for people to understand the impact they have on animals in captivity, whereas if you had them in the wild as early as you can they would rely more on instincts and try to stay away from humans," Walton says.

Lloyd Kiff at the World Center for Birds of Prey disagrees. Kiff, who has worked with condors since the 1960s and directed the recovery team for 10 years, thinks the birds run into problems just because they are too intelligent. "That makes it very hard to work with them. This is not like releasing an eagle," Kiff says. "Eagles are really stupid: They have stereotypic behaviors, they don't think, while condors are thinking all the time. They would sit on top of a car at a McDonald's and take free hamburgers if you let them get away with it."

At Pinnacles National Monument, Court VanTassell explains that if he and his colleagues observe a released condor approaching people constantly, they haze the animal with squirt guns and by yelling and clapping at it. This forces a negative relationship with humans. If that measure doesn't work, the biologists trap the bird and bring it back to captivity for months to years.

In the flight pen, the human-friendly birds are isolated from people and have to deal with other condors, outgrowing their unnatural habits as they age. Moreover, re-captured condors lose their social status in the wilderness while in captivity. When they are released again, regaining their place in the condor hierarchy leaves little free time for them to linger around humans.

But the first measure to prevent condors losing their wild instinct is minimizing human contact while rearing them, VanTassell observes. Caretakers feed the condors only at night, so the birds don't see people. They also try to handle the birds just once before releasing them, to place a tag equipped with a transmitter on their wings and to take blood samples to gauge the amount of lead in their bodies.

Poisonous bullets

Lead levels in the blood of condors are extremely low before they are released. But as the biologists monitor the birds' health each year, they observe a dramatic increase in lead contamination. This can be a death sentence: Lead is a poisonous metal that alters brain and kidney function. It ultimately paralyzes the digestive tract, causing slow and painful starvation.

If biologists detect the poisoned condors in time, they receive therapy with a drug that binds to lead and removes it from tissues. Not all the birds survive, and the therapy is invasive. It requires trapping the condor twice a day to give it shots for a week or more, then keeping it under surveillance until its lead levels decline.

Conservationists had long suspected condors poison themselves by eating leaded bullet fragments from the carcasses and guts of animals discarded by hunters. In 2006, a team of researchers including Molly Church and Donald Smith from UC Santa Cruz confirmed this suspicion. The team showed that the unique chemical fingerprints of bullets match those in blood from poisoned condors.

The researchers took blood samples from 18 free-flying condors and 8 birds in captivity. They found the lead levels in the blood of free-flying condors were nearly 10 times higher, on average, than those in captive birds. The lead's composition matched the chemical fingerprints of lead in ammunition sold in the area.

Previously, the California Fish and Game Commission—which dictates the state's hunting practices—maintained there was insufficient evidence to indicate that ingesting ammunition killed condors. Therefore, agency officials felt no cause to take action against leaded bullets. "We undertook this study to demonstrate unequivocally. . . that there really was a direct link between leaded ammunition and high blood levels of lead in the reintroduced California condors," says Smith.

Prior to this study, a lawsuit seeking a ban on lead bullets in the state's condor ranges was set in motion. And in November 2006, a coalition of conservation and health organizations sued the California Fish and Game Commission and the California Fish and Game Department. Andrew Wetzler, an attorney with the Natural Resources Defense Council, is confident about winning the lawsuit.

Meanwhile, there are individual initiatives to eliminate lead ammunition. For instance, directors of the Tejon Ranch Company in Kern County announced they would ban lead bullets on their property, starting in January 2008. The company owns 270,000 acres of land where the condor ranges. Nearly 2,000 hunters come to the ranch each year to hunt deer, elk, wild pigs, and other game.

In search of safe meals

"When you step back and take a look, you see there's really no way you can have a sustainable [wild condor] population with lead in the environment," says Jesse Grantham, California condor coordinator for the U.S. Fish and Wildlife Service in Ventura, California.

Grantham says the lead problem exists in all the release sites. In Arizona, four condors died in January 2007 because of lead poisoning. An additional problem imperils the birds in the Grand Canyon State: The population there is "experimental" and is not covered under the Endangered Species Act, because it is not within the historic condor range. Even so, the Arizona Game and Fish Commission voluntarily started offering lead-free bullets to hunters in 2005, focusing on areas frequented by condors.

Meanwhile, conservationists feed condors with calf carcasses to ensure a safe source of food. Each release site has semi-permanent feeding areas, surrounded by electric fences to keep predators away. But even with these reliable meals, the condors keep getting poisoned by leaded fragments because they are excellent foragers, explains VanTassell. "It is unfortunate that usually the birds flying farthest and doing best in the wild are those that find trouble," the biologist says.

Furthermore, these naturally curious birds, when given a bunch of time and no concerns about food, usually start behaving oddly. They may approach humans or pick up small pieces of toxic trash, like PVC plastic, wire, or glass, and feed them to their chicks. If the trash blocks the baby condor's intestinal tract, it will die.

Biologists are puzzled about why condors do this. There are two possible explanations, according to Jesse Grantham. First, condors have a naturally calcium-deficient diet, so they compensate by ingesting small pieces of bones. Possibly, they mistake microtrash for bones. Alternatively, condors may ingest rough-edged pieces to aid their digestion by grinding up food.

As attempted solutions, conservationists make the birds spend much more time looking for food, setting new feeding sites in different areas to prompt their natural foraging behaviors. They also provide the condors with chipped-up bone fragments.

Emerging dangers

Some of the hazards the condors faced when biologists started releasing them in the early 1990s have declined. "Electrocution is actually not quite as big," Grantham says. The last time a bird hit a power line was in July 2006. Three measures led to this success. The first one is placing a mock power pole inside the flight pen, where the young condors are kept before release. The power pole emits a small electrical charge when a condor tries to land on it, so the juvenile birds learn to avoid perching there.

But this doesn't prevent the condors from flying into electric wires. That's why the electrical utility company PG&E collaborated with the recovery program by attaching two types of "flight diverters"—yellow coils and clips with a spinning reflector—to the power lines. These diverters make the lines more visible so birds can avoid them. Finally, biologists have located safer release sites, with fewer chances for condors to strike power lines.

However, Grantham warns, there are emerging hazards. Last year, biologists began suspecting the condors are encountering DDT through marine animals along the central California coast. The suspicion was aroused by finding a thin-shelled egg matching the pattern of DDT-affected eggs in the 1960s. "We are waiting for birds to nest again this year to see what the story is," Grantham says. Re-emergence of DDT—thought to come from condors feeding on sea lions and other marine-mammal carcasses—could lower condor hatch rates.

The last serious hazard is the growing human population in the condors' historic habitats. "Places that 25 years ago were considered fairly remote and pristine are now becoming important recreational sites, like Los Padres National Forest," Grantham says. He believes these pressures will escalate tremendously within the present range of the condor. Soon, biologists will need to find new, less-crowded release places.

For the condor to escape the endangered species list, three targets must be met: two different breeding populations of 150 individuals each in Arizona and California; 15 breeding pairs in each population; and a positive population growth. So far, the results paint a bleak picture of the condor's future. The recovery program has released birds for 15 years, but of 17 nesting attempts by condors in the wild in California, only two wild chicks have fledged successfully. In Arizona, there are now three wild-fledged young birds flying free, with one other in temporary captivity.

Will condors ever overcome the hazards they face to reach those objectives, or will they perpetually depend on human caretakers? "The condors are behaviorally, instinctively, and biologically prepared for anything they naturally encounter," says Court VanTassell, outside the holding pen at Pinnacles. But their recovery hinges on whether society will make room for these iconic birds and protect them for generations.


ABOUT THE WRITER

María José Viñas
B.Sc., veterinary medicine, Universitat Autònoma de Barcelona, Spain
B.A.,journalism, Universitat Pompeu Fabra, Spain
Internship: Sea Studios, Monterey

Maria Jose Vinas According to one of my high school teachers, I was good at both science and humanities. When she told me that science would be a more useful thing to study, I believed her. My mother insisted that I study medicine as a university student, but in a rebellious outburst I chose veterinary medicine instead. (Ok, I wasnít such a big rebel). Soon I was facing hysterical pet owners, filthy pig farms, and monotonous lab work. The drudgery made me realize I wasnít meant to be a vet. I was angry with science, and I didnít want to deal with it again. But once I began to work as a journalist, I realized scientists are some of the most interesting subjects to interview, because they are enthusiastic about their work. Now, through my stories, I want to spread their passion.

ABOUT THE ILLUSTRATOR

Pedro Fernandes
Licenciatura, geology, Faculdade de Ciências da Universidade de Lisboa, Lisbon, Portugal

Pedro Fernandes It all began a long time ago: the indecision between a life in science and a life in arts. The decision fell upon science, and I ended up taking a degree in geology, where I got very interested in paleontology (indecisions, indecisions, biology or geology? Paleontology allows you to have both!). Apart from geology, I had some other interests in natural sciences: ichthyology first, ornithology soon after. And although I tried to focus just in being only a scientist, for some reason I kept sketching. But something was amiss. I found out what when I met Pedro Salgado, former Science Illustration student at UCSC. With him I learned that there was a contact point for illustration and art. Thanks to Pedro, I learned about Science Illustration, and found my way to Santa Cruz. It took me 8 years to finally take that leap. But I never really had an option…