Slow down for purple martins

By on July 25, 2022

NCDOT temporarily lowers speed limits on Umstead Bridge

(North Carolina Department of Public Transportation)

A purple martin house at the William B. Umstead Bridge in Manns Harbor. (NCDOT)

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.

Beginning July 25, the N.C. Department of Transportation will temporarily lower 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.   

From late July through August, the west end of the bridge becomes home to as many as 100,000 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. The flock is so large during its peak that it can be seen on radar.

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.

As an alternative, motorists can use the Virginia Dare Memorial Bridge. Those wishing to view the flock safly can do so at Dare County’s multi-purpose pier at the west end of the bridge.






  • Michael E C Gery

    For the third straight summer, the population of purple martin families roosting overnight at the bridge is far lower than in the past. The Coastal Carolina Purple Martin Society has no satisfactory explanation for this, but we are looking into it. Meantime, visitors to the Umstead Bridge at dawn and dusk between now and mid-August will not see the usual swarms of birds that have roosted here for more than 40 years. We thank NCDOT, Dare County Sheriff’s Department and everyone for their interest and support. —The Coastal Carolina Purple Martin Society

    Tuesday, Jul 26 @ 8:05 am
  • surf123

    Instead of the birds we need NCDOT to lower the speed limits to 25mph where it is currently from 35mph. This will save humans. The birds are irrelevant when compared to a single human life.

    Tuesday, Jul 26 @ 10:07 am
  • Dethrol

    Damn nonresident, tourist birds…..

    Wednesday, Jul 27 @ 2:14 pm
  • Charles

    Can we get some of these birds to pop over to Rt 12 to slow people down ?

    The speed limit signs don’t work.

    Friday, Jul 29 @ 1:00 pm
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