Bald Eagle Poisoned By Lead: Patient 22-1974
As rehabilitators, we always strive to do our best, but sometimes, the outcome is not always a triumphant one.
Patient 22-1974 came to us on GivingTuesday in November 2022 in severely emaciated condition. The Bald Eagle was found grounded (unable to fly) in Felton, PA, and upon examination, the outlook was grim — He showed several signs of lead poisoning.
Pennsylvania Bald Eagle Populations
Bald Eagles have experienced their ups and downs in Pennsylvania. In the late 1970s, there were only three nests left in the whole state. Populations had been in decline for years because of over hunting, unintentional poisoning from DDT (an insecticide), lead poisoning and habitat destruction. Numerous conservation efforts nationwide, plus the banning of DDT, worked to restore these majestic birds to the skies. Now ,there are more than 300 nests in Pennsylvania!
However, the plight of the Bald Eagle is far from over, and their struggles come straight from the hands of humans. Wildlife rehabilitators and other conservation organizations are working to help preserve these emblematic birds.
Lead Poisoning in Bald Eagles
Of all the Bald Eagles tested by Pennsylvania wildlife rehabilitation centers between 2006 and 2016, 1/3 of them had measurable levels of lead in their systems. At the Wildlife Center of Virginia, 75% of the Bald Eagles they have admitted within the past 10 years were found with the same lead poisoning.
As scavengers, Bald Eagles (and other birds of prey) are highly susceptible to lead poisoning. Lead poisoning occurs when an animal — or human — ingests traces of lead. For eagles, this lead can come from ammunition fragments left in unrecovered carcasses or gut piles, or from lead fishing tackle that was lost or improperly disposed of.
When an eagle eats parts of a deer or other carcass that contains lead, the lead dissolves and absorbs into their bloodstream. Even if the fragment fully passes through their digestive system, the lead will remain in their body and continue to cause problems. A fragment of lead the size of a grain of rice is enough to kill a Bald Eagle.
Detrimental Effects of Lead Poisoning
Lead poisoning can cause an eagle to become uncoordinated, resulting in impaired mobility. In patient 22-1974, that meant he was unable to fly. Poison continues to weaken any animal that’s ingested it, causing them to starve. In some cases, it can even lead to seizures. In the wild, lead poisoning is often fatal for eagles, but in rehabilitation, the best cases of treatment can require long-term supportive care. Unfortunately, patient 22-1974 was unable to survive, passing away shortly after admission.
Our Responsibility
It’s our responsibility to prevent cases like 22-1974’s from happening again. While lead ammunition was banned for waterfowl hunting in 1991, it’s still legal in all other types of hunting. Lead hooks and tackle are also still legal for use in fishing.
Choosing to use alternative types of ammunition and tackle like copper bullets or tungsten fishing weights, can prevent animals from ingesting detrimental pieces of lead. If you’re still using lead ammunition to hunt, be sure to obscure any carcasses or gut piles by burying the remains you won’t use to prevents eagles (or any wild animals) from scavenging the poisoned meat.
While the end of patient 22-1974’s story may not have been a happy one, we can work together to write new, happy stories for the other Bald Eagles of Pennsylvania.
Resources and Further Reading
Bald Eagle from IUCN Red List
Bald Eagles & Lead from Pennsylvania Game Commission
Bullet Fragments in Deer Remains: Implications for Lead Exposure in Scavengers by Hunt et al.
The Case of DDT: Revisiting the Impairment from U.S. Environmental Protection Agency
How Do Raptors Get Lead Poisoning? from Wildlife Center of Virginia
Lead Toxicity in Raptors from Wildlife Center of Virginia
