MANNS HARBOR - The annual summer purple martin roost has begun on Croatan Sound, and that means it is time for motorists to slow down for the birds.
From late July through August, the west end of the William B. Umstead Bridge becomes home to thousands of purple martins as they prepare for their annual migration to Brazil. The birds roost under the bridge at night, departing at dawn to feed and returning at sunset. In the past, the flock has been so large during its peak that it could be seen on radar.
To better protect drivers and the birds, the N.C. Department of Transportation has temporarily lowered speed limits from 55 mph to 20 mph on the William B. Umstead Bridge at dusk and dawn. The Umstead Bridge in Dare County is known locally as the Old Manns Harbor Bridge.
Since 2007, NCDOT has partnered with the Coastal Carolina Purple Martin Society to educate the public about the flock and protect the birds and motorists. NCDOT activates flashing lights and lowers the speed limit on the bridge at sunrise and sunset. The speed limit is monitored by law enforcement and allows motorists and birds safe passage across the sound. Since the lights and speed limits were installed, the Coastal Carolina Purple Martin Society has seen a dramatic decline in bird deaths around the bridge.
This year, a bridge preservation project is also underway on the Umstead Bridge, and a lane closure is currently in place at the west end, controlled by portable traffic signals. However, the project is not expected to impact the birds, as work will not be occurring between 7 p.m. and 7 a.m. during the nesting period.
As an alternative, motorists can use the Virginia Dare Memorial Bridge. Those wishing to view the flock safely can do so at Dare County’s multi-purpose pier at the west end of the bridge.