Wobbly Bald Eagles Dying From Brain Disease

Seven more bald eagles have been found dead at Thurmond Lake this week, bringing to eight the number of eagles believed to have been killed in Georgia this year by a mysterious malady first diagnosed five years ago.

The eagles, found in Lincoln County, may have died of Avian Vacuolar Myelinopathy, said Vic VanSant, a Georgia Department of Natural Resources biologist.

AVM first was diagnosed in eagles at DeGray Lake, Ark., in 1995, where 58 birds have died. Scientists have since been unable to determine the origins of the condition.

Erratic Behavior Before Death

“None of these eagles have been confirmed as having AVM, but it’s suspected, obviously, because all the symptoms are there,” VanSant said.

The symptoms — wobbly, erratic behavior and an inability to fly — are caused by microscopic lesions that destroy the brain. Ducks and geese also have been found with AVM, which is always fatal.

Thurmond Lake was the first location outside of Arkansas where AVM was identified. Two eagles died at the 70,000-acre lake in 1998, and a third — found at Savannah River Site — also was diagnosed with AVM.

The seven eagles found this week — and one found in Columbia County before Thanksgiving — will be analyzed by the University of Georgia’s Southeastern Cooperative Wildlife Disease Study Center.

The Athens-based facility is working with the National Wildlife Health Center in Madison, Wis., the U.S. Fish & Wildlife Service and other agencies and universities to determine the causes of AVM.

Scientists from the National Wildlife Health Center were to be at Thurmond Lake today, along with researchers from the Corps of Engineers’ Waterworks Experiment Station in Vicksburg, Miss., to discuss the eagle deaths.

One theory is that coots, aquatic birds, ingest material associated with an algae bloom that may produce toxic agents fatal to bald eagles, which often dine on coots.

Tests of coots along the Savannah River have confirmed the presence of the condition, and at least one Canada goose also was confirmed to have died from AVM.

Wildlife authorities are concerned another outbreak of AVM would harm the already-sparse eagle population along upstate South Carolina reservoirs. Two eagles were found dead in South Carolina last year, and five died in Arkansas.