ARI SHAPIRO, HOST:

Bald eagles have made a remarkable recovery from when they were an endangered species in the 1960s. In fact, there are so many now that a lot of them get injured by cars and poisoned by lead. Randi B. Hagi with member Station WMRA visited a rehab hospital in Virginia that's seen a record number of eagles in recent years.

(SOUNDBITE OF BALD EAGLE SQUAWKING)

RANDI B HAGI, BYLINE: Two new patients were en route to the Wildlife Center of Virginia in the foothills of the Blue Ridge Mountains when I visited.

(SOUNDBITE OF BALD EAGLE SQUAWKING)

HAGI: Dr. Karra Pierce was expecting the arrivals.

KARRA PIERCE: One of them - I think it just was found on the ground, not flying. And then the other one is coming from, I think, Virginia Beach - is a transfer from a rehabilitator. And I believe it had a leg injury.

HAGI: While eagles have made a remarkable recovery, with increasing numbers come more eagles trying to find habitat and food alongside humans. That's when they get hurt.

PIERCE: We get a ton of bald eagles that were hit by cars. Oftentimes they're actually scavenging on the side of the road.

HAGI: This center alone admitted a record-breaking 66 bald eagles last year. They're on track to match that number again this year. Besides roadkill, eagles also feed on the remains of carcasses left behind by hunters. That heightens the risk of lead poisoning from fragments of ammunition.

PIERCE: They have a really, really, really acidic stomach, so that acid interacts with the lead and basically leeches the lead out.

HAGI: Pierce said three out of every four eagles coming in here test positive for some amount of lead in their blood. The American Eagle Foundation warns that a lead fragment the size of a grain of rice can be lethal to a bald eagle.

PIERCE: The biggest impact we see is certainly from the neurologic effects.

HAGI: When their brains are impaired by lead poisoning, they have a harder time avoiding cars. Federal agencies and outside researchers think ammo is the most likely culprit, but there could be others. Some experts noted cases of poisoning were most common during hunting season. Federal efforts to ban lead ammo have so far failed in Congress.

PIERCE: For lead intoxication, we're going to be starting them on a lot of different medications that basically pull the lead out of the blood so they can excrete it themselves.

HAGI: If an eagle responds to this treatment, it goes through rehab at the center and is eventually returned into the wild. Last year the center released just nine bald eagles. The other 57 died or were euthanized due to their injuries. For NPR News, I'm Randi B. Hagi in Waynesboro, Va.

(SOUNDBITE OF SEAL SONG, "FLY LIKE AN EAGLE") Transcript provided by NPR, Copyright NPR.

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