All Birds of Prey, especially vultures, are at risk of lead poisoning. This is caused by the ingestion shards of lead-based ammunition, from both feeding on carcasses of production and domestic animals that have been deliberately killed using lead bullets, or by ingesting entrails or carcasses left behind by irresponsible hunters.
When ingested in large enough quantities, lead has detrimental effects on the nervous and reproductive systems. Birds with lead poisoning will exhibit loss of balance, gasping, tremors and impaired ability to fly. Emaciation follows and death can occur within 2 to 3 weeks after lead ingestion.
In order to lessen the effect that remains of lead ammunition is having on our endangered vulture populations, farmers and landowners leaving need to understand the risks of lead poisoning. If carcasses killed using lead bullets are to be left accessible to vultures, bullets and any shards of lead need be removed. Similarly, hunters need to be made aware of the impacts of lead on the environment, and the use of environmentally safe, non-fragmenting copper bullets needs to be endorsed and encouraged.
Many landowners in the Maloti-Drakensberg range will deliberately leave lead bullet-slaughtered animals accessible to vultures, believing they are providing a safe meal for the birds, when in fact they are unknowingly contributing to the demise of the species.
For more information, check out this site detailing the benefits of non-lead bullets