Lynn Thompkins of Pendleton prepares a bird for an X-ray at Pendleton Veterinary Clinic. - AP

Lead poisoning found in raptors

PENDLETON — Last April, a golden eagle was brought to Blue Mountain Wildlife, a raptor rehabilitation center in Pendleton. Center director Lynn Tompkins said the bird was suffering from classic symptoms of lead poisoning.

The poisoning caused nerve dysfunction to such a degree that the eagle clenched its talons and couldn't unclench them. They were so tightly contracted the bird was walking around on his knuckles, Tompkins said. In addition, the eagle was emaciated because poor muscle control prevented hunting.

Tompkins took the eagle to Pendleton Veterinary Clinic where a lead toxicity test was done. The eagle had a lead level of 66.4 micrograms per deciliter. A normal level is under 6 micrograms per deciliter. Tompkins said the eagle was named "66" after the alarming lead level.

Raptors get lead poisoning from eating prey that has been killed or wounded by lead shot. The eagle eats the pellet along with the other meat, and while it sits in the eagle's stomach, lead slowly poisons its body.

The lead usually doesn't stay there. Like other raptors, eagles regurgitate pellets containing any indigestible material. Anyone who has happened upon an owl pellet has seen bone and feathers wrapped in a neat little bundle.

So when Tompkins receives an injured eagle and gives it an X-ray, lead shot will probably not show up. But lead poisoning will be present in the eagle's blood.

Seven months later, 66 has been cured of lead poisoning, but suffers arthritis as an aftereffect. Tompkins said 66 can't be released into the wild, and she is looking for a permanent home at an educational facility.

Unfortunately, 66's case of lead poisoning wasn't the only one this year. The bird is the fourth golden eagle that has come up positive for lead poisoning. The other three eagles were not showing obvious symptoms. Tompkins said the only way she knew was by running the tests.

"It might not be obvious that they have lead, but it could affect coordination," she said.

As a result, these eagles are often hit by cars or suffer other coordination-related injuries.

One eagle Tompkins took in was found hanging from a power pole.

"He couldn't let go," she said.

The second golden eagle's lead level was 33 micrograms per deciliter. That eagle was brought to the rehabilitation center because it was hit by a car.

The third bird was 66.

Then on Oct. 30, a golden eagle was admitted that had been hit by a car. Blood tests revealed it had a lead level of 61 micrograms per deciliter. Unlike 66, it did not show any obvious signs of lead poisoning.

Oregon Department of Fish and Wildlife biologist Mark Kirsch said bald eagles will often eat waterfowl (such as ducks) since they hunt along waterways such as the Columbia River.

But golden eagle territory is usually more upstream. The golden eagles ingest lead shot from eating wounded or dead upland game birds or small mammals, Tompkins said.

"Anything that's injured sticks out like a sore thumb," she said. "It only takes one pellet."

And the more carcasses the eagles eat, the more lead is absorbed by its system. Over time, the result is a lead-sickened raptor like 66.

Tompkins said it's equally likely the hawks she receives at the center may also suffer from lead poisoning without showing symptoms. But she does not have the appropriate funding to test the hawks under her care, just the eagles.

Cooney said there is a national movement to lower lead levels in animals all along the food chain.

This is especially the case for waterfowl, he said. Not only is there the secondary danger to eagles and other water raptors, but there is the initial danger to ducks, swans and geese.

Often, a hunter who shoots lead shot misses. That lead then sinks to the bottom of the lake or river, which is where the waterfowl eat. Unlike raptors, these birds cannot regurgitate the lead they ingest. Instead, it just sits in their systems, slowly poisoning them.

Kirsch said in Oregon, lead shot and other poisonous ammunition is illegal to use on waterfowl.

That's not the case for upland game birds, where golden eagles hunt. He said hunters see lead as a superior projectile to alternatives like steel. Lead is more dense. It can fly farther and carry more energy as it flies, making it more likely to kill a bird.

Steel shot can also damage some gun barrels that weren't made for it.

For Tompkins and Cooney, who see the far-reaching effects, the answer is simple.

"Don't use lead shot," Tompkins said. "There are non-lead alternatives."

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