Oakland Zoo to treat endangered California condors for lead poisoning

Prehistoric animals with wingspans the length of automobiles will be arriving at the Oakland Zoo soon to receive treatment for the health effects of a chemical that continues to threaten their survival. The California condor, the largest flying land bird in North America, has been on the endangered species list since 1967, and now sick pairs of the bird are slated for arrival at the zoo’s new condor treatment center in March.

California condors’ survival has been threatened by a pollutant that conservationists have been fighting to regulate for decades—lead. “Lead poisoning is the number one threat to these guys,” said Andrea Goodnight, an associate veterinarian at the Oakland Zoo. Condors are strictly scavengers, Goodnight said, that eat dead mammals such as deer, sheep and cattle. The vulturous creature contracts lead poisoning when it feeds on carcasses of game that have been shot with lead bullets. Shot animals and gut piles are sometimes left on the field by hunters, Goodnight said, and ingested by scavengers like the condor.

Cases of condors acquiring lead poisoning were so rampant that by 1987, there were only 22 condors left in the world, with the US Fish and Wildlife Services listing lead poisoning and random shootings as the main causes of their declining numbers.

Lead poisoning causes neurotoxic effects, first making the birds lethargic. “They get very weak,” Goodnight said. “They can’t really walk. You’ll see them kind of falling over and then eventually they can’t feed themselves.” That’s because the poisoning slows down their gut and makes it so that their gastrointestinal tract—the part of the digestive system that transports water and nutrients—can’t move. “Basically, the bird slowly starves to death,” Goodnight said.

In July 2008, a state law began prohibiting the use of lead ammunition for hunting deer, elk, wild pig, and pronghorn antelope in areas inhabited by the condor. But the problem, Goodnight says, is that the birds sometimes fly out of their range to find meat to scavenge, so lead continues to be a threat to the species.

Today there are approximately 200 condors in the wild, and another 200 in captivity, Goodnight said. Every surviving wild California condor is currently tracked with GPS and satellite tags, so biologists know where the birds are and can detect when they are moving more slowly, a sign that they might be sick.

This fall, the Oakland Zoo partnered with the California Condor Recovery Program, a conservation effort involving the US Fish and Wildlife Services and a number of wildlife facilities, to help the condor population grow by treating them for lead poisoning. The zoo’s new facility, which was funded by its conservation fund and donations from companies including FedEx and AT&T, is very simple, Goodnight said. It has an indoor workroom and two chain-link fence pens that are each 15-by-15 feet wide and 9 feet tall. A partition board separates the two pens, since biologists have learned that, despite being social creatures, not all condors are compatible. Part of the facility has an overhang; the other part is out in the sun. Inside the facility, zoo staffers will administer chelation therapy, which pulls lead out of the birds’ blood.

Visitors to the zoo will not be permitted inside the condor treatment facility, Goodnight said, to prevent the birds from socializing too much with humans and losing their natural instincts. But a live webcam has been placed in their pens, so that once the birds arrive, Internet users can watch them all day and all night. “We want them to stay acclimated so that they can return to the wild,” Goodnight said. “The goal is to return the birds as quickly as we can to their natural habitat.”

Goodnight said that the zoo will most likely receive its first sick condor in March when biologists at the Ventana Wildlife Society (in Big Sur) and Pinnacles National Park (in the Central Valley) test the lead levels of the condors currently living in these wild spaces. Biologists test the wild condor population two times a year. Prior to the creation of the Oakland facility, the nearest place to treat condors living in Big Sur and the Central Valley were the Los Angeles or San Diego zoos, Goodnight said.

“This project was huge for us,” said Nicky Mora, the spokesperson for the Oakland Zoo.

Nancy Filippi, the operations manager at the Oakland Zoo, also expressed enthusiasm at the zoo’s new ability to help a nearby species. “This is near and dear because it’s right in our backyard,” she said. Teams of biologists, conservationists and veterinarians like Goodnight are pushing for the public to be aware of the plight of the condor and the continuing need to preserve the species. In one effort to promote awareness of conservation, the first condor cameras in the wild are being set up in Big Sur by Camzone Networks, a live streaming video and web cam service provider, so that footage of the state’s condor in its natural habitat will be accessible to bird watching novices and experts alike.

It’s important to pay attention to the health of the condor, Goodnight says, because if a species that’s been around for nearly 100,000 years can perish due to man-made causes, so can other kinds of animals. “Even if you don’t care about the condor in particular,” she said, “if the condor goes, other species are going to follow.”