Studying Lead in Condors

Researchers from the Weisskopf Lab measured the bone lead of condors at the Vermilion Cliffs near Marble Canyon, AZ (near the north rim of the Grand Canyon) from January 12-15 2018.

Lead-based ammunition is a primary source of lead exposure, especially for scavenging wildlife. Lead poisoning remains the leading cause of diagnosed death for the critically endangered California condors, which are monitored annually via blood tests for lead exposure. The results of these tests are helpful in determining recent exposure in condors and in defining the potential for exposure to other species including humans. Since condors are victim to acute and chronic lead exposure, being able to measure both would lend valuable information on the rates of exposure and accumulation through time. Our group has validated the use of a portable x-ray fluorescence (XRF) device for measurements of bone lead in vivo in humans and in lab samples from condors. Since most of the surveillance data for condors is collected in the field, this device can contribute valuable information on lifetime lead exposures by measuring bone lead in avian species. Working with the The Peregrine Fund, a non-profit organization dedicated to saving birds of prey from extinction, our study aimed to validate the measurements of bone lead against serial blood lead measures, and use other tracking data to identify potential differences in behavior and associated health outcomes in the condors.