New study shows fatal effects of lead poisoning on Bald and Golden Eagles throughout North America

Golden eagle scavenging a deer carcass in Pennsylvania. © David Brandes

Cape May, NJ – A paper recently published in the journal Science by researchers at Conservation Science Global, Inc., the U.S. Geological Survey, West Virginia University, the U.S. Fish & Wildlife, and others, shows that nearly half of studied Bald and Golden Eagles exhibited chronic lead poisoning, and that lead poisoning is a substantial barrier to the growth of eagle populations across North America. This paper, “Demographic implications of lead poisoning for eagles across North America,” is the first to show continent-wide consequences of lead poisoning on any species of wildlife.

Lead is a highly toxic heavy metal that is ingested by eagles and other scavenging wildlife when feeding on the remains of animals that have been shot with lead ammunition. “This is the first study of lead poisoning of wildlife at a nationwide scale, and it demonstrates the unseen challenges facing these two iconic eagle species” says lead author on the study and Research Wildlife Biologist for Conservation Science Global, Dr. Vince Slabe. “Medical science tells us that, for humans, there is no safe amount of lead. Today we also know that redistributed lead in our environment is harming eagle populations across North America.”

This study evaluated lead exposure in more than 1,200 Bald and Golden Eagles sampled between 2010 and 2018 and found age-related and seasonal variation in lead poisoning. “A few studies have shown these trends at a local level” says Dr. Todd Katzner, co-author and Research Wildlife Biologist for the U.S. Geological Survey, “but demonstrating these patterns at a continental scale helps us to understand what causes this variation and, potentially, how to address the issue.”

Chris Parish, President and CEO of The Peregrine Fund and co-founder of the North American Non-lead Partnership agrees, “With an ever-growing body of scientific findings, we hunters have an ever-improving understanding of the details of preventable exposure. The hunting community has a long-standing tradition of conservation of wildlife in the United States, and we are the key to solving the problem. Through the efforts of the North American Non-lead Partnership, we are finding that with appropriately delivered information, hunters and anglers who are asked to help are eager to do their part in improving ecosystem and wildlife health. Wildlife agencies, sporting groups, and tribal communities, are coming together to increase awareness and solve this problem on behalf of wildlife across North America.”

“Now that we have evidence that lead is affecting eagles nationwide, we are poised to address this problem”, says Slabe. “Already, Native American tribes, groups like the North American Non-lead Partnership, Conservation Science Global, and others, are encouraging voluntary use of non-lead ammunition. As a scientist and hunter, I value our conservation heritage and I see this study as another opportunity to grow awareness of this issue.”

Conservation Science Global (CSG) was founded in 2016 to benefit local, regional, and global communities by conducting scientific research to advance conservation and management of natural resources. CSG educates the public, scientists, and policy makers about the results and implications of this research. From studying Golden Eagle and California Condor movements to tackling the issue of lead in wildlife, we are advancing conservation and management of our natural resources through science and education. CSG is a 501c3 non-profit supported mainly by foundation, corporate, and government grants.