Biologists at Pinnacles National Monument have captured 10 of the 11 free flying California condors that fed on rodent carcasses shot outside the monument with lead ammunition. Initial field tests Friday, June 23rd and Tuesday, June 27th, revealed that four juvenile condors have elevated levels of lead in their bloodstream, between 30 and 51 micrograms of lead per deciliter of blood (µg/dL). "This level of lead found in these condors is of concern because it proves these birds ingested a significant amount of lead" explained Jim Petterson, Supervisory Wildlife Biologist for Pinnacles National Monument. Had we been able to immediately capture the birds while they were feeding on these rodents, their blood lead levels would have likely been high enough to warrant x-rays and possibly required transporting to the Los Angeles Zoo for further treatment.
The remaining captured birds have tested below 20 µg/dL, a currently accepted level based on the condition of the environment. All recaptured birds have been given shots of Vitamin K-1 to counteract the effects of possible rodenticide ingestion. National Park Service scientists are attempting to trap condor 307, the remaining bird in question.
The Pinnacles condors may still face health problems because of the elevated levels of lead in their blood. While the levels measured are not high enough to warrant emergency measures, long term exposure to non-lethal levels remains a serious problem. Lead in a condor’s bloodstream will be absorbed into its bones, where it can slowly leach back into the blood for more than a year.
The vast majority of research on the health effects of lead exposure is based on humans, butcomparisons can be made for animals. When a child's brain is developing, even low levels of lead in the body can slow the child's development and cause learning and behavior problems. It can change the way blood-forming cells work, alter the way nerve cells signal each other, and disturb or destroy the way the brain makes connections for thinking. Some of the Pinnacles condors are testing at three times the level that would initiate a medical response in humans as outlined by the Center for Disease Control. At this time, the effects of lead exposure on juvenile condors are only measured in mortality rates.
The local community has shown increasing support for the Condor Reintroduction Program. In the last two weeks, local ranchers have helped biologists place a remote trap to capture the condors roosting outside the park and many have committed to using non-lead ammunition.
Without community support, this opportunity to bring California condors back into the wild will not succeed.
• Jim Petterson, Supervisory Wildlife Biologist, Pinnacles National Monument, 831.389.4485 x 223
• Denise Louie, Chief of Research and Resource Management, 831.389.4485 x 222
• Chris Ketchum, Ranch Foreman, Paicines Ranch, 831.801.7910 (Local rancher who switched from lead ammunition to copper in response to the condor reintroduction.
Last updated: February 28, 2015