2 Illinois eagles died from lead poisoning this month, and toxic hunting ammunition is likely the culprit
The bald eagle was struggling for breath when it arrived at the Illinois Raptor Center in Decatur. Seizures shook the bird’s iconic snow-white head. Its dark wings rose and stiffened at awkward angles.
“Aw, man,” program director Jacques Nuzzo said to himself. “This is lead.”
He rushed to the eagle’s aid and stayed late into the night, dispensing difficult-to-obtain medication, as well as fluid for hydration and kind words for comfort. But the seizures continued, racking the bird’s body every five or 10 minutes.
By noon the next day, the patient was dead.
Such suffering is largely preventable, experts say, with studies showing a strong link between widespread lead poisoning in eagles and the use of lead ammunition by deer hunters. The ammunition fragments and disperses in a deer’s body, and eagles ingest it when they feast on “gut piles,” the internal organs that hunters remove and leave behind.
Other forms of ammunition are available — including copper and tungsten options — but information hasn’t been readily available to hunters, and uptake has been slow.
“It gets more frustrating every time I see one (of these cases). It’s really awful,” said Nuzzo, who treated the lead-poisoned eagle March 8, just two days after another eagle with lead poisoning died on its way to the same raptor center.
“This is a problem that has been going on for over 80 years, and it’s a little mind-blowing that nothing has really, majorly, been done about it,” Nuzzo said.
The Illinois Raptor Center, a 25-acre wildlife rehabilitation and education facility, has admitted 38 bald eagles since 2018, Nuzzo said. Of those, 19 had unhealthy lead levels and 8 died from lead poisoning.
The lead-poisoning issue got additional attention in February when the journal Science published a study of more than 1,200 eagles in 38 states that were tested for lead from 2010 to 2018. Almost half the eagles in the study had chronic lead poisoning.
The study found that cases of recent lead poisoning rise in winter, when eagles are most likely to be feeding on contaminated deer carcasses and gut piles.
Other studies show similar correlations and older research — conducted with portable X-ray devices up to 20 years ago — found that hunters’ discarded carcasses often contained lead fragments, according to study co-author Vincent Slabe, a wildlife research biologist at the nonprofit Conservation Science Global in Bozeman, Montana.
In addition, wildlife rehabilitation centers with X-ray machines have been able to show that when eagles have high lead levels, they often also have lead fragments in their digestive systems.
“When you start piecing all of that together, there are very strong correlations suggesting that this is the pathway whereby eagles are lead-poisoned,” Slabe said.
The U.S. banned the use of lead ammunition in waterfowl hunting in 1991, due in part to concerns that the birds were experiencing lead poisoning, and California banned all lead hunting ammunition in 2019. A lead hunting ammunition ban was introduced in the Illinois Senate in 2019 but didn’t gain traction.
The Congressional Sportsmen’s Foundation, which has opposed lead ammunition bans, could not be reached for comment.
Some eagle advocates lean toward a ban, with Nuzzo saying that at this point “it’s probably the best bet.”
But Slabe disagreed, saying that bans can easily backfire, putting hunters — who tend to be pro-conservation and sympathetic to eagles — on the defensive.
“I’m pro-hunter. I’m pro-conservation. I’m also pro-eagle,” Slabe said.
He said information about the affect of lead on eagles hasn’t been widely available, and he cited an Arizona study that found that after a comprehensive public relations and education program, more than 80% of hunters took steps to protect California condors from lead poisoning. The hunters either switched to non-lead ammunition or put their gut piles in trash bags and removed them from wildlife areas.
Slabe said that when a deer is shot, lead bullets fragment and disperse in the animal’s body, leaving dozens — or even hundreds — of pieces of toxic metal, some of them only a little larger than the head of a pin.
If an eagle eats the contaminated meat, lead can cause problems with breathing, circulation, reproduction or respiration. Some eagles with lead poisoning lose their ability to fly. Eagles can also suffer brain damage or get food stuck in the crop — a storage area in the esophagus — and starve to death.
The lead poisoning problem is serious enough to suppress population growth for the estimated 340,000 eagles living in the United States, Slabe’s study found.
The bald eagle population, which currently increases by 10% a year, would increase by about 14% without lead poisoning, the study found. Similarly, the golden eagle population would grow at a rate of about 1% a year, up from zero growth today.
A hunter and fisherman, Nuzzo had already eliminated lead from most of his outdoor equipment when he treated the lead-poisoned eagle earlier this month, but that experience has inspired him to go further.
Now, he said, he’s working on removing the last remnants of the toxic metal from his fishing gear.
“It has to start with us,” Nuzzo said. “It would be a lot easier if you made the choice, rather than the government telling you what to do.”
