Two tiny songbirds have successfully traveled thousands of miles from their wintering grounds somewhere in South America back to the North Carolina mountains, all with a tiny backpack strapped to their rumps.
Earlier this month, biologists snagged two Golden-winged Warblers in mist nets in Madison and Yancey Counties—the same individuals that they trapped and tagged with a tracking device in the same location last spring.
The tracking devices send out radio signals, which are picked up by towers outfitted with receivers, called Motus towers, as the birds fly by.
A total of 14 Golden-winged Warblers were tagged by Audubon, the NC Wildlife Resource Commission, and our partner researcher Dr. Darin J. McNeil of the University of Kentucky. According to data collected with the devices, one of the recovered birds and another tagged in Ashe County last spring traveled south after the breeding season and pinged towers at St. Marks Wildlife Refuge and Chasshowitzka National Wildlife Refuge on the west coast of Florida.
After that, the data go dark, although the birds themselves likely traveled to wintering grounds in Colombia or Venezuela, before returning to the very same hillside in North Carolina this spring.
“No matter how long I’ve been doing this, I forget sometimes how absolutely stunning and amazing these birds are,” said Curtis Smalling, Interim Executive Director at Audubon North Carolina. “A Golden-winged Warbler weighs less than the change in your pocket, yet these two birds flew across the hemisphere to return to the very same spot they were initially tagged right here in our backyard. We’re hopeful that the data they are generating will help us better protect and restore the places they need most.”
The birds are part of a long-term project to study the movements of Golden-winged Warblers, coordinated by Audubon and many partners and led by Amber Roth at the University of Maine. Across the East Coast and Midwest, researchers are trapping Golden-wings and outfitting them with light-weight radio trackers called nanotags.
The goal is to learn more about how this rare songbird moves across its range, and what threats might be causing its population to dwindle. In southern Appalachia, Golden-wings have declined as much as 98 percent since 1966.
Because the Motus tower network is still being built out, there’s no guarantee when or where tagged birds will be detected, or if they will ping any towers at all. That’s why Audubon and our partners are working to bring more towers to North Carolina. Last year, we worked with Cape Fear Audubon and UNC Wilmington’s Danner Lab to install a new Motus tower at Lea-Hutaff Island, which has already revealed interesting insights into shorebird migration.