Bald eagles are being poisoned by lead across South Carolina, and in some cases, the majestic birds are dying from exposure to the toxin that scientists blame for eagle deaths nationally.
Since 2013, two-thirds of the eagles tested at a Lowcountry wildlife center have shown potentially harmful levels of lead in their blood.
Last year, 78 percent of the eagles brought to the Center for Birds of Prey had elevated lead levels, the Charleston County organization reports. The center, which treats birds for injuries and illness, tests every eagle brought in for medical attention.
“We have birds that come in that appear dead or comatose,’’ center director Jim Elliott said. “Some we are able to revive and some we have lost. We’ve had birds die with lead poisoning that are beyond the point of treatment when they arrived.’’
Test results by Elliott’s organization bolster years of concerns nationally about lead’s effects on bald eagles, iconic raptors that became the nation’s symbol more than 200 years ago.
Numerous scientific studies have documented elevated lead levels in the blood of bald eagles in recent decades.
Studies during the past 40 years by the University of Minnesota’s raptor center show that 90 percent of the eagles tested annually have elevated lead in their blood. In New York state, 83 percent of the more than 300 eagle carcasses examined since the mid 1990s showed exposure to lead, according to 2017 Associated Press story.
Any number of reasons could be to blame for the elevated lead readings, but evidence suggests that eagles are eating the remnants of animals killed by hunters who use lead ammunition. The lead, still contained in the carcasses of animals that are killed, works its way into the blood stream of eagles after they consume the leftover meat.
In 2013, more than a dozen respected scientists called for a reduction in the use of lead ammunition by hunters. The group, which included researchers from Harvard University and the University of California, said lead bullets can fragment into hundreds of small pieces and be ingested by scavenging wildlife.
"Many hunters don't realize that as much as 50 percent of a bullet may remain in the deer as fragments," Virginia wildlife researcher Ed Clark told the AP last year. “A sliver the size of a grain of rice is enough to kill a bald eagle in 72 hours."
Some hunters sharply dispute arguments that lead bullets are to blame,saying evidence is inconclusive. Many prefer to use lead bullets and shotgun shells because the ammunition is cheaper and more accurate.
Larry Bachman, a South Carolina hunter active in the National Wild Turkey Federation, said a box of lead shot is about half the price of some other types of ammunition. Bachman said he also would be surprised if lead shot was the reason eagles are showing lead in their blood.
“I would think it is more the lead in the atmosphere or lead pollution from (industrial) plants,’’ Bachman said.
Either way, experts say there’s little doubt lead is a threat to bald eagles across South Carolina.
“It turns out the majority of the birds we’re testing have elevated blood lead levels,’’ Elliott said. “It certainly is a real threat to these birds. Understanding more about how they might be exposed and what we might do is important.’’
In at least one instance, eagles tested in the Palmetto State have had higher levels than were found two neighboring states, a Birds of Prey Center researcher said. The U.S. Department of Agriculture recently found that eagles tested for lead in South Carolina had higher levels than eagles in Florida or North Carolina, said Debbie Mauney, the Birds of Prey Center’s medical clinic director.
Eagles exposed to high amounts of lead become lethargic or act erratically, or in some cases stop eating and become emaciated. Lead is a naturally occurring element used for an array of purposes, but it is toxic to both people and wildlife, according to the U.S. Environmental Protection Agency.
Charlotte Hope, a biologist with the S.C. Department of Natural Resources, said concerns about eagles ingesting lead are no surprise. Bald eagles are known as fierce predators that hunt small animals and fish, but Hope said they also are voracious scavengers that will peck at contaminated carrion.
One of the most likely sources of lead contamination are deer “gut piles,’’ or mounds of deer carcasses not carved away by hunters, some experts say. These piles still contain, in many cases, the lead-based shot hunters used to kill the deer. When eagles see a deer pile, they swoop in and begin eating the lead-contaminated meat.
In the past, bald eagles have been sickened from eating the carcasses of dogs and cats euthanized at animal shelters, Hope said. The animal carcasses still contained the drugs that killed the animals.
“They can get into trouble more often than some other birds of prey,’’ Hope said.
So far, the widespread effect of lead on bald eagles has not hurt the resurgence of the once rare bird, statistics show. South Carolina has about 3,000 bald eagles today, including about 370 nesting pairs, Hope said. In 1985, about 330 eagles were found in South Carolina, including about 30 nesting pairs. A ban on DDT, a chemical that was killing bald eagles in the 1960s, helped populations recover.
Bald eagles are dark brown birds distinguished by their white heads and tail feathers. Powerfully built, they can weigh up to 14 pounds and have wingspans of eight feet, according to the U.S. Fish and Wildlife Service. Bald eagles live near lakes, rivers and marshes across South Carolina.
The federal government outlawed the use of lead shot by duck hunters nearly 30 years ago after evidence mounted that waterfowl were mistakenly eating fragments of ammunition that fell to the ground. But the use of lead shot for other hunting was never banned nationally or in South Carolina.
That needs to change, animal welfare groups say. Nicole Paquette, a vice president at the Humane Society of the U.S.,said hunters should shift to other forms of ammunition that are not as toxic, such as copper or steel bullets.
President Barack Obama issued an order before leaving office that would have banned lead ammunition by hunters on federal land, but that was quickly overturned after President Donald Trump took office last year. Trump’s Interior Secretary, Ryan Zinke, dropped the Obama lead shot ban, saying it was not necessary.
Some hunting groups, including the National Rifle Association, applauded Zinke’s action.
State Rep. Mike Pitts, a Laurens County Republican active in hunting issues, said he’s seen no conclusive evidence that lead shot or bullets are hurting eagles or other wildlife.
Efforts to ban lead ammunition could chill hunting by making it more expensive for sportsmen. A father wanting to take his children hunting could encounter quite an expense if ammunition prices rise, Pitts said. Pitts also said the use of lead shot is actually more humane because it kills animals faster.
“It’s cheaper, it’s more accurate and it hits with more energy,’’ Pitts said. “You have much fewer wounded animals with lead shot than you do with steel shot. It does the job. If I’m shooting doves or quail, pheasant, no matter what, if I hit them with lead shot, they go down. With steel shot, they may fly off and die.’’
Eagles and lead poisoning
The S.C. Center for Birds of Prey says most of the eagles it treats for injuries or illness have elevated levels of lead, a toxic metal, in their blood.
Eagles with high lead levels