When fall and winter arrived, Dickerson Park Zoo started seeing a disturbing trend — rescued bald eagles sick, weak and unable to fly because of lead poisoning.
The zoo's Raptor Rehabilitation Program does its best to save the big birds — our nation's symbol. But Dr. Stephanie Zec, the zoo's veterinarian, said that since 2020 only five out of 12 bald eagles sickened with lead were able to be successfully treated and released to the wild.
The other seven? They're euthanized.
“These cases are intense,” Zec said during an interview at the exam table where dozens of eagles have been treated in recent years. “We give them a drug that binds the lead and pulls it out of their system, but it's a race against time. These are not easy cases to turn around.”
About a month ago, a conservation department agent rescued an eagle in the West Plains area that was sickly and unable to fly.
Before taking the bird to Dickerson Park Zoo, the agent did an educational show-and-tell at a West Plains school to convey to the youngsters the seriousness of lead poisoning in bald eagles.
The agent caught a lot of heat from bird lovers for not immediately taking the eagle to the Raptor Rehabilitation Program. Zec, however, said the one-day delay wouldn't have made any difference with the eagle she nicknamed Long Shot.
She said eagles begin to show signs of sickness when lead levels reach 10 or 20 micrograms per deciliter in the blood.
“When Long Shot came in, it had 1,094 micrograms per deciliter in its blood,” Zec said. “We tried to save him. We had him for a week and a half before we had to put him down.”
In December, three eagles arrived at the raptor program suffering from lead poisoning, followed by three more in January.
Zec, and wildlife researchers in other states, believe the odd clustering of lead poisonings in the fall and winter might be a result of eagles scavenging on gut piles left in the wild by deer hunters, a disposal method long accepted by conservation officials.
“There seems to be a seasonality with lead,” Zec said. “We think that lead fragments from bullets end up in the gut piles. Eagles are scavengers and they go for the gut piles. Even the tiniest fragments of lead can break down quickly in an eagle's acidic digestive system.”
Zec said it's possible that eagles might also be ingesting lead if they catch or scavenge fish that have swallowed lead fishing lures or tiny lead fishing weights. But the fact that most lead-poisoned eagles are found in the fall and winter — during and after deer hunting seasons — makes the fish connection less likely.
Zec emphasized that the zoo is not against deer hunting, which she noted has a long tradition in Missouri. She added that several zoo staff members are deer hunters.
However, the zoo is planning a “Get the Lead Out” campaign in the fall to help educate the public about the lead problem and hopefully encourage hunters to consider using non-lead bullets, such as solid copper projectiles, when they go afield.
They hope that educational message could slow the trend of lead-poisoned eagles like the bird nicknamed No Fly, which is currently in long-term rehabilitation at the Raptor Rehabilitation Program.
During a recent visit to No Fly's enclosed flight cage, Zec said the male eagle got its name because it just would not fly, despite making progress with its overall health.
The eagle arrived in December and still had not flown — until a reporter stepped inside the enclosure with Zec to take some pictures. The eagle flapped its wings and then surprisingly swooped up to an elevated perch.
“He hasn't been able to get height like that,” Zec said. “He's not ready for the big leagues (release) yet. I am encouraged to see him get up to the big perch today.”
Francis Skalicky, a spokesperson for the Missouri Department of Conservation, said the agency is aware that lead is affecting some Missouri eagles and other scavenger wildlife. Although MDC is not actively researching the problem, he said the agency is working with the Midwest Association of Fish and Wildlife Agencies “to investigate how much of an issue this is.”
“This is not an anti-hunter issue, it's an educational issue,” Skalicky said. “Hunters have always been on the side of wildlife. That's what they enjoy, being outdoors and seeing wildlife. But hunters who are doing nothing wrong could be a part of it.”
Skalicky said he was aware of studies in other states that appear to show lead bullet fragments as a source of lead poisoning in eagles. A Cornell University study of seven northeastern states, for example, found higher death rates in eagle populations because of lead poisoning, and also a correlation between lead poisoning and deer hunting seasons.
Why not just switch to non-lead bullets for hunting?
Solid lead or lead-cored bullets covered by a copper jacket are typically less expensive than solid copper or other non-lead bullets. There would be a financial cost for hunters who decide to make the switch in an effort to protect eagles from lead poisoning.
Nick Newman, owner of Cherokee Firearms in Springfield, said it's more costly to manufacture solid copper bullets than lead core ones.
He looked up the pricing on a typical .30-06 deer hunting round. A box of 20 with copper-jacketed lead bullets was selling for $32, or $1.60 per round.
He said a box of 20 solid copper cartridges cost $55, or $2.75 per round.
“If I'm going to Colorado to hunt elk, there's not that much difference in going from lead to copper, compared to the overall cost of the trip,” he said.
Skalicky said MDC currently has no plans to require hunters to switch to non-lead bullets or change the way they dispose of deer gut piles.
“MDC is about education on an ongoing basis,” he said. “If we need to bury gut piles or move to nontoxic shot that's a conversation we can certainly have.”
Lead poisoning of bald eagles is not just a problem in Missouri. In January 2017, former President Barack Obama directed the U.S. Fish and Wildlife Service to phase out the use of lead ammunition and lead fishing tackle by 2022, because of lead's toxicity to eagles and other wildlife.
However, on his first day in office, former President Donald Trump had his Interior Secretary Ryan Zinke reverse Obama's order.
In 2013, California became the first state in the nation to begin phasing out the use of lead-based hunting ammunition because the state's rare and endangered condors were ingesting lead and becoming sick and dying after scavenging hunter-killed animal carcasses.
California's ban on lead hunting ammunition took full effect in July 2019.
In 1991, the U.S Fish and Wildlife Service banned the use of lead pellets for waterfowl hunting nationwide. Lead pellets scooped up by ducks as they fed proved to be lethal to them. And eagles or other raptors that hunted lead-contaminated waterfowl also developed lead poisoning.
Steel shot or other nontoxic shot is now required in waterfowl hunting areas.
Skalicky said he thinks any regulatory change about the use of lead bullets for hunting would likely come at the federal level.
