ALBANY — Bald eagles have made a remarkable recovery across the United States since the pesticide DDT was banned 45 years ago, but the majestic birds are still dying from another environmental poison: lead from bullets and shotgun pellets in wildlife carcasses left behind by hunters.
In New York State, which has been a leader in the bald eagle restoration in the Northeast for four decades, state wildlife researchers have documented a growing number of eagle deaths from lead poisoning in recent years. Wildlife rehabilitators have also seen increasing numbers of eagles testing positive for lead in Minnesota, Oregon, Virginia and other states.
Eagles and other scavengers eat the guts of deer or the carcasses of coyotes, woodchucks and other game shot by hunters. Bits of lead bullets consumed along with the meat break down quickly in an eagle’s stomach and enter its bloodstream.
Elevated lead levels cause blindness, paralysis, lack of appetite and neurological problems that make eagles more likely to fly into buildings or vehicles — if they don’t succumb to lead poisoning first.
Ed Clark, president of the Wildlife Center of Virginia, said about 60 percent of the 35 to 40 eagles they treat each year have lead in their blood.
“Many hunters don’t realize that as much as 50 percent of a bullet may remain in the deer as fragments,” Carter said. “A sliver the size of a grain of rice is enough to kill a bald eagle in 72 hours.”
In New York, lead poisoning was confirmed as the cause of death in 38 of 336 bald eagles brought to a Department of Environmental Conservation lab near Albany between 2000 and 2015, said state wildlife biologist Kevin Hynes, who does the necropsies. Nine bald eagles were confirmed as lead-poisoning deaths in 2016, and seven so far this year.
While lead poisoning isn’t threatening the eagle population as a whole, the impact on individual birds is worrisome, Hynes said.
“We’re getting more eagle deaths overall because the eagle population has increased,” he said.
When state biologists launched a restoration program in 1976, hand-rearing baby eagles captured in Alaska and releasing them in New York, there were no reproducing bald eagles in the state. This year, New York’s bald eagle population hit a record 323 breeding pairs.
The Humane Society of the United States has long sought restrictions on lead ammunition, beyond the 1991 federal ban on lead shot for waterfowl hunting. California is the first state to ban hunting with lead bullets, phasing them out by 2019 in favor of less-toxic copper or steel.
On former President Barack Obama’s last day in office in January, Fish and Wildlife Service Director Dan Ashe signed an order calling for phase-out of lead ammunition on federal lands by 2022. President Donald Trump’s new Secretary of the Interior, Ryan Zinke, reversed Ashe’s order on his first day in office.
Such restrictions are vehemently opposed by the National Rifle Association and other hunting and gun rights organizations.
Copper bullets, the main alternative to lead, are more expensive and harder to find than traditional ones. There’s also a debate over whether they perform as well.
Virginia wildlife advocate Clark said that rather than focusing on banning lead ammunition, his group is seeking a public education campaign to educate hunters about the problem and how they can help.
“It can be easily solved by not leaving the remains of animals where scavengers can get to them, or to simply use non-lead ammunition,” he said. “This information needs to be in every hunter safety course.”