Recently captured condors have elevated levels of lead
More than half of the California condors from Pinnacles National
Monument and Big Sur had elevated levels of lead in their systems
when tested this week.
Recently captured condors have elevated levels of lead
More than half of the California condors from Pinnacles National Monument and Big Sur had elevated levels of lead in their systems when tested this week.
“The level of lead found in these condors is alarming not only because they are some of the highest recorded levels, but because we are unsure of the extent of developmental and long-term health problems resulting from the significant amount of lead they have ingested,” said Court VanTassell, a wildlife biologist at Pinnacles National Monument.
Three of the birds had levels indicating lead poisoning – 306, 318 and 242 – and were taken to Los Angeles Zoo for emergency chelation, according to a Pinnacles National Monument press release. The process removes heavy levels from the bloodstream when lead levels are higher than 40 micrograms per deciliter of blood. Ten other birds also had lead levels that showed they were exposed to the metal.
Biologists captured the birds for testing after they saw five condors feasting on a pig carcass outside the park that had been shot with lead ammunition.
One of the Big Sur condors had a lead level of 610 micrograms – more than 15 times the safe level – and another bird from Pinnacles had a level of 164 micrograms.
Research conducted by the University of California, Santa Cruz and Pinnacles staff has shown lead ammunition is a significant source of lead exposure and poisoning in California condors, though they are still researching pathways of transmission.
Research is still needed to understand the long-term effects of non-lethal levels of lead in condors. Lead can be absorbed from the bloodstream into a bird’s bones and then leach back into the blood in the future.
Most of what is known about the effect of lead is based on studies of human exposure. Low levels of lead slow brain development in children, and can cause learning and behavioral problems. It may also change how blood-forming cells work, alter the way nerve cells signal each other and disturb or destroy the way the brain makes connections for thinking. In addition, lead causes problems for kidneys and the immune system.
For more information on the Condor Reintroduction Program or on Pinnacles National Monument, visit www.nps.gov/Pinn or by calling 389-4485, ext. 0.
