(CNN) - Some of the nation's top experts Tuesday were looking for clues into sudden, mass deaths of birds in two states over New Year's weekend.
"This one is unusual because of the time period over which so many birds died," said LeAnn White, a field investigator with the National Wildlife Health Center in Madison, Wisconsin. The center, part of the U.S. Geological Survey, is receiving samples from Arkansas, where as many as 5,000 red-winged blackbirds and starlings fell from the sky in a square-mile area in less than an hour on New Year's Eve, according to the Arkansas Fish and Game Commission.
The center will also examine samples from Louisiana, where 500 red-winged blackbirds, starlings and grackles were found dead in Labarre.
A preliminary report conducted Monday by the Arkansas Livestock and Poultry Commission found that the birds in Beebe, Arkansas, likely died from massive trauma.
There had been reports of loud sounds in Beebe before the reports of birds falling began to come in. It's possible the sounds made the birds disoriented, and they went into sudden, chaotic flights, crashing into each other and into objects, White said. "You're disturbed, you're disoriented, you're trying to figure out where you are. We have seen some stuff like this before when there's heavy dense fog, and they'll run into towers and power lines," she said.
Other bird experts agree that that's a likely explanation. Still, the sudden deaths are quite unusual. "It's kind of a freak event," said Greg Butcher, director of bird conservation for the National Audubon Society. "You just don't see these kinds of mass deaths very frequently at all."
At this time of year, blackbirds are in huge roosts, particularly throughout the southeastern United States, he said. They generally don't fly at night.
Filed under: 360° Radar
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