August 27, 2001
Wausau Daily Herald
By Pat Peckham
Wausau Daily Herald
A common pesticide probably poisoned two adult eagles in Wausau this summer and made it more difficult for them to feed their young, an expert says.
Marge Gibson, who cares for injured and orphaned raptors in Antigo, said a video of the adult eagles revealed their feet were clenched. She said she thinks they ingested a type of pesticide that contains organophosphates, chemicals that can cause the clenching.
The disorder interferes with an eagle's hunting, landing and perching.
Gibson still is caring for a young male eagle which left the nest on Wausau's north side on July 12 before it was able to fly. The second eagle chick in the nest has been able to fly on its own and was last seen by residents of the area on Aug. 14.
The male is gaining strength and likely will be released in late January below the Prairie du Sac hydroelectric dam, a wintering area for bald eagles. The eagle, known as No. 42 or "Mino's Eagle" because of the proximity of the nest to Mino's Cucina Italiana restaurant, is now 16 to 17 weeks old, Gibson said.
Gibson said there's probably no way to tell where the adult eagles picked up the pesticides.
"It's pretty much everywhere. It's used as a defoliant, a fungicide, an herbicide and on grass in residential areas," she said. "It's really used a lot."
The adult eagles' ability to hunt was impaired, so they were not able to feed their young like a healthy pair could have. With time, the birds can recover as chemical levels in the body subside.
Julie Langenberg, a DNR wildlife veterinarian, said pesticide poisoning can't be confirmed without lab tests, but Gibson could be correct.
"She's making a very educated guess and Marge Gibson's experience with eagles exposed to toxins is great," Langenberg said. "We regularly see cases of pesticide poisoning, including organophosphates, and I'm sure what we see is the tip of the iceberg. I think pesticides are a major issue for eagles in the state."
Gibson and Langenberg said the organophosphates affect the long muscles in a bird's body, so it can use its wing muscles to fly but landings are clumsy and perching can be difficult.
Gibson said she became more sure there is a problem in the Wausau area when someone brought a Cooper's hawk to her from the Franklin Street area last week. Its talons were clenched and it died.
Copyright © 2001 Wausau Daily Herald