By Dr. Becker
The Blue Mountain Wildlife Center in Oregon is among a growing number of rehabilitation centers caring for lead-poisoned bald eagles. In March 2017, they described one eagle with lead levels of 622 micrograms per deciliter of blood, and another with 385 deciliters.
For comparison, children who have blood lead levels of 45 or higher are recommended for immediate treatment, according to the U.S. Centers for Disease Control and Prevention (CDC).1
Lead is toxic in animals, as it is in people. Eagles and other wildlife exposed may have trouble balancing and flying and may suffer from tremors. The birds often stop eating, and may become paralyzed or blind, or suffer from brain damage and organ failure.
Animals and birds may be poisoned by lead in a number of ways, from eating spent lead shot, bullet fragments and lead fishing sinkers while foraging for food to eating another contaminated animal. Eagles, in particular, commonly eat animals that have been shot with lead ammunition, leading to poisoning.
Sadly, raptor biologist Glenn Stewart told The Guardian that up to 15 percent of bald eagles die before their first birthday due to lead poisoning, in large part because the young birds eat primarily carrion.2
US Secretary of the Interior Revoked Ban on Lead in Ammunition and Fishing Tackle
Lead shot was banned for use in waterfowl hunting in 1991, but was still allowed for other types of hunting. A new rule enacted during the Obama administration's last day called for lead ammunition to be banned for use on national wildlife refuges.
Newly appointed Secretary of the Interior Ryan Zinke revoked the ban, however, saying, "It worries me to think about hunting and fishing becoming activities for the land-owning elite."3 Others assert the ban was not an affront to hunting, as alternatives to lead ammunition are readily available.
In March 2017, a group of doctors and scientists sent a letter to the Department of Interior strongly supporting the rule. Defenders of Wildlife also had this to say:4
"It is terribly unfortunate that among the first actions of Secretary Zinke in assuming stewardship of the Department of the Interior was his peremptory revocation of an order that simply sought to protect the wildlife under his care from lead poisoning.
While the issuance of the Director's order triggered complaints from sportsmen's groups regarding lack of consultation, the fact is that the use of lead ammunition is simply unacceptable in this day and age, when there are readily available alternatives on the market and we know the incredible harm that lead poses to people and to wildlife.
Lead ammunition and fishing tackle poison and kill many millions of birds and other animals each year, and risk contamination of our waterways and drinking water."
Unfortunately, without the new rule it will remain legal to use lead ammunition for hunting all wildlife other than waterfowl, except in California. So many California condors were dying from lead poisoning that the state banned all lead hunting ammunition, which is to be phased out by July 2019.
A number of other states have expanded restrictions on lead ammunition beyond the waterfowl hunting ban, but California remains the only state with a statewide ban.
Lead Ammunition Breaks Up on Impact
Once an animal is shot with a lead bullet, the ammunition fragments into hundreds of tiny pieces. It takes just a few of these fragments to kill or poison a bald eagle or California condor, according to the U.S. National Park Service.5
According to the University of Minnesota Raptor Center, 90 percent of the bald eagles that come in to their center for care have elevated lead residues in their blood, with up to 25 percent having levels high enough to cause lead poisoning.6 Over the last 24 years, the center has lost more than 500 eagles due to lead.
A study conducted by the center determined that lead ammunition used in the hunting of white-tailed deer is significantly associated with lead poisoning in eagles.7
Many are not aware that this poses a risk not only to the raptors but also to the people who eat the meat. In a study of packaged venison, for instance, 34 percent contained metal fragments that were made up of 93 percent lead.8
Other animals known to be harmed by ingesting lead include hawks, ravens, turkey vultures and grizzly bears.9
Lead-Free Ammunition Proven to Help Reduce Lead Poisoning in Wildlife
There's no good reason to continue using lead ammunition, particularly since the U.S. Fish and Wildlife Service (FWS) has approved 13 non-toxic alternatives for hunting.10
Ammunition made of steel, copper and bismuth, for example, is widely available in stores and online. Even the U.S. Army is taking steps to get lead out of many of its bullets.
History has shown that switching to lead-free ammunition can have a dramatic protective effect. When the 1991 federal ban on lead ammunition for hunting waterfowl was enacted, major improvements were seen.
Within six years, death of mallard ducks from lead poisoning dropped 64 percent and about 1.4 million ducks were saved each year.11 As toxicologist and condor researcher Myra Finkelstein told The Guardian:12
"The science is overwhelming … The answer is so clear that I wish we could just make the switch and protect human and wildlife health … This has nothing to do with people's right to hunt …
We took lead out of gas and out of house paint. That doesn't mean you don't drive a car or paint your house. It's about using something that's safe for you and your family as well as an animal that comes upon it."