the purple martins of the outer banks
The largest member of the swallow family, Purple Martins are completely dependent on manmade structures to survive east of the Mississippi. The old Manns Harbor Bridge is a natural roost for the birds and they come and go by the hundreds of thousands in the morning and evening. Writing for Outer Banks Common Good, Nancy Proctor does a great job of describing what is happening at the bridge.
“The Outer Banks of North Carolina are famous for beautiful beaches and other natural attractions, including a fascinating roost of purple martins at William B. Umstead Memorial (“Old Manns Harbor”) Bridge. East of the Rocky Mountains, martins are completely dependent on people to provide them with nesting structures in which to raise their young. Without these caring “landlords,” martins would likely become very rare throughout the eastern United States.”