Finkelstein's research quoted in article on extreme condor treatments
With wingspans of up to 3 metres, it should be hard to miss the largest bird in North America – but there aren’t a lot of them. The California condor is only just hanging on in its home state, but thanks to a gargantuan conservation effort, the tide may finally be turning.
To save the species, the last few California condors were taken from the wild in the late 1980s, after lead poisoning from gun ammunition nearly drove the birds to extinction, with only around 22 birds left in the wild. Since 1992, there have been multiple reintroductions to the wild, and there are now more than 150 individuals flying over California and nearby areas in Arizona, Utah and Baja in Mexico, but their survival is still dependent on help from humans.
To establish themselves in the wild, condors have to survive long enough to reproduce. Now, thanks to regular monitoring, training and medical treatment, they are finally on the brink of forming a self-sustaining population.
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A partial ban of the use of lead ammunition throughout the condor’s range in 2008 seems to have had little effect. Condors are usually re-captured about twice a year for blood testing and a study by Myra Finkelstein from University of California, Santa Cruz, and her colleagues, published in 2012 found that about a fifth of wild birds had blood levels that required clinical intervention to prevent sickness and death (PNAS, DOI: 10.1073/pnas.1203141109).