HAMILTON TWP., MONROE COUNTY, Pa. — It was an emotional moment late last month when Napoleon, an adult bald eagle, was released into the wild after months of treatment for heavy metal toxicity.
“You cry tears of joy, because he is back out there, and tears of you’re going to miss him, almost — but this is what we want,” said Kat Schuster, a licensed wildlife rehabilitator and lead clinic manager at Pocono Wildlife Rehabilitation & Education Center.
“This is the outcome that we were looking for and for him. When he first came in, he was eating on his own, then he stopped. There were ups and downs with him.”
Napoleon’s rehabilitation and release into the wild is a bright spot amid a dangerous time for bald eagles in the Lehigh Valley and the rest of the commonwealth.
Bird flu continues to threaten wild bird populations, causing so far more than a dozen bald eagles to be euthanized across Pennsylvania.
‘Positioned to withstand losses'
While local and state experts said decades of conservation work has bolstered the species enough to weather the recent surge of infection, there are plenty of other threats to bald eagles still out there — especially heavy metal toxicity, negatively impacting the species.
Since December, 18 bald eagles statewide have been euthanized because of symptoms of HPAI, or highly pathogenic avian influenza — commonly called bird flu — according to data from the state Game Commission.
That total includes three in Northampton County and four in nearby Berks County.
“Our population also has an abundance of non-breeding adults that are awaiting an opportunity to pair up and often do very quickly. So, eagles would seem well-positioned to withstand losses related to HPAI.”Travis Lau, communications director with the state Game Commission
“In general, bald eagles have a healthy population here,” state Game Commission Communications Director Travis Lau said.
“They are no longer on a list of any threatened or endangered species, which says a lot for a species that as recently as 1983 had only three known nests in Pennsylvania.
“Our population also has an abundance of non-breeding adults that are awaiting an opportunity to pair up and often do very quickly.
"So eagles would seem well-positioned to withstand losses related to HPAI.”
Risk to people remains low
An influenza type A virus, HPAI or H5N1, is highly contagious and often fatal in birds.
It can be easily spread from bird to bird in some species through direct contact with an infected animal’s mucous membrane, feces and/or blood.
The virus, which hit the United States in 2022, has jumped from birds to dairy cows, as well as other mammals, and has caused one human death.
Since early January, thousands of wild and domestic birds in the Valley have been reported infected, including 5,000 migratory snow geese in Nazareth and Upper Macungie townships and a 50,000-bird egg-laying chicken flock on a commercial farm in Lehigh County.
Early last month, the Valley’s two major health networks announced their strategies for the possibility of human cases.
There have been no reported bird flu infections in dairy cows or people in Pennsylvania. Health officials, both locally and nationally, say the risk to people remains low.
‘The worst is behind us’
Recent infections have come amid the annual snow geese migration. However, with warmer weather around the corner, the snow geese should be making their way out of the region.
Each spring, tens of thousands of migratory snow geese make their way through Pennsylvania, heading north to colder climates to breed.
They tend to gather in large, concentrated flocks, increasing the amount of pathogens to which they're exposed.
“I think there’s a lot of hope that the worst is behind us regarding this resurgence of HPAI.”Travis Lau, communications director with the state Game Commission
“Things have tapered significantly in recent weeks, which is reflected by the detection list showing none since March 4,” Lau said.
“Meanwhile, snow goose migration is wrapping up, with the majority of snow geese having already pushed through Pennsylvania.
“So I think there’s a lot of hope that the worst is behind us regarding this resurgence of HPAI.”
The three Northampton County eagles euthanized included birds known to residents, such as one of a mated pair at Minsi Lake Wilderness Area.
Last month, a mature mother bird, known to nest alongside the same mate in a tower at Saucon Park also tested positive. Her surviving companion has since found a new mate.
In addition to bald eagles and snow geese, bird flu has claimed several other of the Valley’s wild animals.
In Northampton County, bird flu is cited as the cause of death for three red-tailed hawks, a great horned owl, a red-shouldered hawk and a black vulture, according to Game Commission data.
In Lehigh County, the virus has caused the death of a red fox, an American cow and two red-tailed hawks.
‘It's common’
Napoleon, found in August in Lehigh County, was covered in human waste and unable to fly by the time Pocono Wildlife rehabilitators worked with him.
“He was basically, completely lifeless,” Schuster said. “We don't know exactly where he got covered in the goo that he was covered in, or how that happened to him. He didn’t tell us.
“He was cleaned up. He was very weak. We did a blood toxicity level — it was high. He did go to the vet several, several times.”
Napoleon, named for his short stature and feisty demeanor, was found to have zinc and copper toxicity, as well as suspected blindness in one eye.
“A lot of the birds that we get in that are high levels, it's lead,” Schuster said. “It's from sinkers, it's from BB guns or bullets. It's very unusual to have zinc and copper.”
Heavy metal toxicity, especially lead, appears to be an increasing problem for bald eagles countrywide. It can cause neurological issues, leg paralysis and organ failure.
“It's common,” Pocono Wildlife lead avian specialist Sampson Metzgar said.
“All eagles have lead in their system that come in — it's just a matter of how high they are. If it's over a certain amount, then it's considered detrimental.”
‘The silent killer’
A 2022 study cited by the American Eagle Foundation found just shy of half of bald and golden eagles surveyed had signs of chronic lead poisoning.
“A lead fragment the size of a grain of rice is lethal to a mature bald eagle, meaning that a standard 150 grain lead bullet can poison 10 eagles."American Eagle Foundation
“A lead fragment the size of a grain of rice is lethal to a mature bald eagle, meaning that a standard 150 grain lead bullet can poison 10 eagles,” according to the foundation’s website.
“The deadly metal accumulates in an eagle’s system over the course of their lives, meaning that there is no safe amount of lead exposure.
“For this reason, lead is often called ‘the silent killer.’”
When a bird comes to the center with heavy metal toxicity, it’s heartbreaking, Schuster said.
“They lose weight, they stop eating,” she said. “They are just basically sitting there with their head hanging. And to see a majestic bird in that state is heartbreaking.”
Research shows exposures often are the result of unintended consequences from lead ammunition fragments and fishing tackle that are left behind in the field.
“You have the hunters that hunt responsibly, and the fishers that fish responsibly make sure that they're taking their arrows, sinkers back with them,” she said.
However, there are many who don’t, and it’s only a matter of time before wild animals become exposed.
“We don't know how [Napoleon] ingested that much zinc or copper, but he was on what's called chelation off and on for several weeks, back and forth to the vet,” she said.
Chelation therapy binds heavy metals, removing them through excretion.
‘They're all success stories’
While Napoleon came into the center eating on his own, he soon stopped, but staff continued to work with him, eventually finding success.
By December, he was eating well and his blood tests were coming back normal, officials said.
“I like to think it was a trust thing and that he was feeling much better and getting his strength back,” Schuster said. “But there’s no way to really know.”
There was worry that he wouldn’t be releasable, because of the blindness in one eye, but Schuster said he started following his food with that eye, too.
He soon moved to a larger enclosure, where he built his strength and bided time, waiting for a break in the icy winter weather.
“He was flying around the cage. He was landing on the perches,” she said. “We have a large tree stump in there that he would land on and eat.
"The prey testing went well, and then it was a matter of just waiting for weather. February was so snowy and so icy.”
Near the end of February, Napoleon was released on the grounds of the center. Staff watched as he flew around before landing on the top of a tree.
“For me, they're all success stories,” Schuster said. “Because even if they don't make it, they were warm. They were safe. They weren't being attacked by something else and dying in that way.
“These things matter to us — the quality of life and the quality of death.”
Residents who see a dead or sick animal, can report it to the state Game Commission by calling 1-833-PGC-WILD (1-833-742-9453).
