On Thursday, April 21, 2022 at 2:52:42 PM UTC+8, David P. wrote:
> At Least 36 Bald Eagles Have Died in Bird-Flu Outbreak
> By Jennifer Calfas, Apr. 18, 2022, WSJ
>
> Bald eagles are among the millions of birds nationwide being
> infected with highly pathogenic avian influenza, a viral disease
> with a high mortality rate for birds like chickens and raptors.
> Since February, at least 36 bald eagles have died from the
> bird flu across the U.S., according to the U.S.D.A.
>
> The escalating bird-flu outbreak is one of the worst in the U.S.
> in several years, according to the Agriculture Dept, spreading
> along Florida, up the East Coast and as far west as Colorado
> and the Dakotas. The highly contagious disease is also hitting
> egg-laying flocks of chickens, as well as commercially raised
> turkeys, leading to a surge in egg and turkey breast prices.
>
> For the bald eagle, the outbreak comes as the population faces
> another deadly problem: a high incidence of lead poisoning. A
> study published in February found population growth rates for
> bald eagles are being suppressed by 3.8% because of lead exposure.
> Lead, a neurotoxin, has many sublethal effects on eagles that affect
> their health and ability to defend their territory and produce eggs.
>
> “It’s concerning,” said Victoria Hall, executive director at the
> Raptor Center at the University of Minnesota. “You’re pairing a
> population who’s already dealing with a lead toxicity problem
> now with highly pathogenic avian influenza.”
>
> In recent weeks, 12 bald eagles with bird flu have arrived at
> the Raptor Center. The eagles, who were otherwise at their prime
> age for breeding, were at the end-stage of the virus and suffered
> from issues like seizures and being unable to stand, according to
> Dr. Hall. Humane euthanasia was the best option for them at
> that stage, she said.
>
> “We’re seeing more bald eagles die from high-path avian influenza
> than we’ve previously documented in any outbreak of this virus,”
> Dr. Hall said. “And it’s interesting, because many of these birds
> also have lead poisoning.”
>
> About 85% to 90% of eagles brought to the center have levels of
> lead in the blood—and about 25%-30% have lethal levels, Hall said..
>
> Eagles are hunters, but they also scavenge, including on dead
> animals and bits of carcass shot and left behind by human hunters.
> Most hunting ammunition is made of lead, and bullets can fragment
> when entering an animal’s body, possibly contaminating remains.
>
> “Right now I don’t think we can say anything except both lead
> toxicity and HPAI were present in some of the birds,” said Hall.
>
> The U.S. CDC said last month the bird-flu outbreak poses a low
> risk to the general public, as it is predominantly an issue among
> animals. Human infections from bird-flu viruses are rare, according
> to the CDC.
>
> Bald eagles were removed from the federal list of endangered species
> in 2007. Their population in the lower 48 states has grown from
> 72,434 individual birds, including 30,548 breeding pairs, in 2009,
> to 316,700 individual eagles, including 71,467 breeding pairs,
> between 2018-2019, according to a report from the Interior Dept last year..
>
> It's unclear what the broader and long-term impact of this bird-flu
> outbreak on the bald eagle’s population will be as it is still under
> way, Dr. Hall said.
>
> “We're seeing significant mortality,” she said, “and the better
> data we can collect about what is happening in these populations,
> the better we can figure out how we can best support them.”
>
> https://www.wsj.com/articles/at-least-36-bald-eagles-have-died-in-bird-flu-outbreak-11650302381

If lead is found in bird's ecosystem, not only eagles can have it, but also include of other birds, too. One key thing in US is that they still use lead pipe in the water piping system to households and so on. The lead in the water system drank by birds in the ponds or water bodies will have a detrimental effect on them, too.

The bird will have virus respiratory and liver problems from lead infection.. Some birds like eagles ate rats and small animals that were infected with leads, too. The infection from small rat or animals will cross-infect the eagles or birds when they ate them.

Whatever, food remnants left behind by the birds will be ate by other small animals and insects, too. They will also be infected with similar bird-flu virus in the respiratory and liver system. However, much depends on their immune system to fight the their infection or else they will perish as dead animals or insects for other insects and animals to eat them as foods, too..