Bird Studies Implicate Lead Bullet Residues as a Possible Threat to Human Health

For Immediate Release: April 30, 2008

, American Bird Conservancy, 202/234-7181 ext. 216
Susan Whaley, 208-362-8274, 208-860-2641 cell,




(Washington, D.C.) Studies of several bird species, including the endangered California Condor, have provided extensive documentation of the health hazard posed to birds that ingest lead ammunition residues in the remains of gun-killed animals. Now, new studies suggest that humans who eat game shot with lead ammunition may also be at risk. A conference to further explore these links, "Ingestion of Spent Lead Ammunition: Implications for Wildlife and Humans," sponsored by The Peregrine Fund, will be held May 12-15, 2008, at Boise State University.

X-rays revealed that packages of venison contained lead fragments (circled in red) in a study by The Peregrine Fund. Photo: The Peregrine Fund.

“We’ve been studying the effects of condor lead ingestion for years,” said Rick Watson, Vice President of The Peregrine Fund, a conservation organization that leads the California Condor recovery program in Arizona. “Condors are sickened and some die from eating the remains of shot animals. The possibility that other species, including humans, are also at risk prompted us to organize this conference.”


Recently published research suggests that even very low levels of lead exposure in children can cause learning disabilities, and in adults may increase risk of Alzheimer’s disease and death from stroke or heart attack. Lead is also associated with impaired visual and motor function, growth abnormality, neurological and organ damage, hearing loss, hypertension and reproductive complications. The degree of lead exposure associated with many of these problems is much lower than previously believed.


North Dakota state health officials recently ordered food banks to discard donated venison because it can contain lead fragments. Dr. William Cornatzer, a Bismarck physician and member of The Peregrine Fund board of directors, made the discovery after learning about the problem in a Peregrine Fund report. Cornatzer collected about 100 one-pound packages of ground venison from food pantries in December and ran CT scans on the meat. The North Dakota Health Department confirmed the presence of lead in its own tests. Cornatzer plans to present his findings at the conference.


"The lead studies have once again shown us that we ignore the plight of birds at our own peril," said Dr. Michael Fry, Director of Conservation Advocacy at American Bird Conservancy. "Condors, eagles, ravens, and other wildlife have given us advanced warning of a problem that we are now learning may also have human health consequences."


The Peregrine Fund will present results of its own recent investigation on lead in hunter-killed animals at the conference. The group is studying the amount of lead in venison from deer shot with standard lead bullets, which fragment into hundreds of tiny pieces upon impact. Their previously published research has shown that these fragments scatter widely into the meat along the bullet’s path of travel. Preliminary results of The Peregrine Fund’s current study will be given at the conference on May 13. The final report will be published in a peer-reviewed journal.


California Condor. Photo: FWS

A recent study found elevated levels of lead in Common Ravens during the hunting season for deer and elk in the Yellowstone region. Scavengers, such as ravens and raptors, eat offal piles left by hunters, or animals that were shot and not recovered. These remains contain lead bullet fragments. Derek Craighead and co-authors of the raven study, are expected to present additional data at the conference showing that lead is also reaching elevated levels in Golden Eagles, Bald Eagles, and other scavengers during the hunting season.

"Unfortunately, the study of ravens in the Greater Yellowstone Ecosystem indicates that poisonings of birds, both scavengers and raptors, by lead bullets is a widespread problem," said Dr. Fry.


Recently, there has been a great deal of attention on the problem of lead bullets due to the poisonings of endangered California Condors, highlighted by several independent studies that will be presented at the conference. The use of lead bullets has been banned in the California range of the condor, and work continues to protect the species in Arizona through voluntary use by hunters of non-lead ammunition.


"When informed of the severity of the problem for condors, most hunters in Arizona have chosen to use non-lead ammunition to benefit wildlife," added Watson, "and once the results from the conference become widely understood, hunters may also choose non-lead ammunition to benefit themselves and their families."




Established in 1970, The Peregrine Fund works worldwide to conserve biological diversity by restoring endangered birds of prey and identifying their key environmental threats, ecology, and relationship with humans. The organization restores rare species through captive breeding and releases, conserves habitat, improves capacity for local conservation, and conducts scientific research and environmental education. More than 80 percent of The Peregrine Fund’s annual budget is privately funded. Administrative costs are almost entirely funded by an endowment, allowing 96 percent of donations to go directly to raptor recovery.


American Bird Conservancy is the only organization that works solely to conserve native wild birds and their habitats throughout the Americas. ABC acts to safeguard the rarest bird species, restore habitats, and reduce threats, while building capacity in the conservation movement. ABC is the voice for birds, ensuring that they are adequately protected; that sufficient funding is available for bird conservation; and that land is protected and properly managed to maintain viable habitat. ABC is a 501(c)(3) membership organization that is consistently awarded a top, four-star rating by the independent group, Charity Navigator.