Least terns (Sternula antillarum) are the smallest seabird that nests on South Carolina’s coast. It is similar in size to a Northern Cardinal (Cardinalis cardinalis). The least tern also begins nesting earlier than most seabirds like royal terns and brown pelicans. In late April, the least tern arrives at the coast from South and Central America and begins nesting in mid-May. Like other seabirds the least tern nests in a group called a colony, but unlike other seabirds in South Carolina, the least tern often nests on flat pea gravel covered roofs. This year in South Carolina 60 percent of the least tern nesting sites were on roofs.
Since the early 80's in South Carolina, least terns have nested on roofs. Because of increased coastal development, less suitable beach nesting habitat remains for the least tern, and it has adapted to making its shallow nest scrapes in the pea gravel substrate found on some roofs. During the 2013 nesting season least terns nested on 13 roofs found in Charleston, Berkeley, Horry, and Kershaw Counties. The largest least tern colony on a roof was at the ALCOA plant near Goose Creek in Berkeley County; this roof had 126 nests. The most successful colony was at the Springmaid Resort in Myrtle Beach, Horry County with 94 nests and at least 74 fledged young terns. The colony furthest away from the coast (105 miles as the crow flies!) was at Camden High School in Kershaw County. The most unusual colony site was beneath the Ravenel Bridge in Charleston. The least terns nested on the flat surfaces of concrete supports which were covered in broken clam shells. The shell pieces were left when during the winters gulls broke open the clams after dropping them on the supports. “The concrete supports are shaded during part of the day and the least terns are not disturbed!” said biologist Mary-Catherine Martin of the Ravenel Bridge colony sites.
The S.C. Department of Natural Resources (DNR) works with business owners who have least terns nesting on their roofs provide an environment which enhances the reproductive success of the nesting terns. Questions about the nesting terns are answered; roof enhancements like a hardware cloth fence to keep young from falling to the parking lot and additional shade structures are provided and placed. The business is recognized as a partner with DNR in providing habitat for the least tern which is a state recognized “non-game species in need of management.” If while shopping next summer in the Myrtle Beach area and you notice a small sign in the window recognizing the business as a least tern conservation partner, please thank them!
For additional information, contact Mary-Catherine Martin at MartinMC@dnr.sc.gov.
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