Lead is Poisoning California Condors to Extinction

The population rebound of the California Condor stands as one of the greatest conservation stories ever, with the species surviving whilst on the brink of destruction. At one point, there were only 22 of the birds left. Now there are nearly 400. So, while it’s out of the extreme red zone, the condor is still one bad turn away from extinction. That stroke of bad luck may have arrived in the form of lead-poisoning that’s reached epidemic levels.

According to a report out today in PNAS, the condor population is being systematically being poisoned by lead, which is most commonly attributed to lead shot and bullet fragments. The study reviewed more than 1,100 blood samples taken from 1997-2010 from wild California condors and found lead levels high enough to kill without treatment in 48% of the birds.

Condors are scavengers, and eat “between 75 and 150” animals a year, which means leaves ample opportunities for a bird to ingest lead.that any bullet fragments floating around can end up killing a condor.

“Lead poisoning is preventing the recovery of California condors,” Myra Finkelstein, a research toxicologist at UC Santa Cruz and a lead author of the study, told the Mercury News “The population is not self-sustaining.”

“If just one has a lead bullet fragment, that can be enough to kill the bird,” she said.

Of course, the lead threat to condors isn’t news. Then-Governor Arnold Schwarzenegger signed a partial ban on the use of lead shot in 2008, which, despite lead alternatives being available, still was met with uproar by hunting groups. The partial ban hasn’t worked; the study found no difference in lead levels between birds tested before and after the regulation was passed.

“Lead exposure and poisoning levels in condors continue to be epidemic,” co-author Dan Doak, a professor at CU-Boulder, told PhysOrg. “Despite the current efforts to help the species, the wild population will decline again toward extinction in a few decades unless these unsustainable and very expensive efforts continue in perpetuity.”

The condor recovery program isn’t cheap: the study said the bill for the efforts, which includes the U.S. Fish and Wildlife Service and numerous state agencies, runs $5 million a year. That on its own makes efforts harder to support with tight state budgets, but, as the authors state, the program itself is unsustainable: the work still only mitigates the adverse effects of lead poisoning, and isn’t helping create stable population growth. So what’s the solution? Well, either we figure out how to make the lead disappear, or we’ll keep putting a very expensive band-aid on the problem until the California condors themselves are gone.

Follow Derek Mead on Twitter: @derektmead.

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