Tropical Storm Idalia dramatically alters Deveaux Bank Seabird Sanctuary

September 14, 2023

Tropical storm Idalia made dramatic impacts on Deveaux Bank Seabird Sanctuary, a protected and critical seabird habitat located in the mouth of the North Edisto River that is owned and managed by the S.C. Department of Natural Resources.

Two-thirds of the island is now underwater from mid-tide to high tide due to overwash and erosion caused by the storm. The western tip of the island, closest to Edisto Island, and the stretch of beach along the oceanfront bore the brunt of the storm’s impacts, while the dune ridge along the northern edge of the island, facing Seabrook Island, remained dry and intact. SCDNR biologists surveyed the sanctuary after the storm had passed to assess habitat.

"Fortunately, the brown pelicans that nested along the side of the island facing Edisto Island had mostly fledged (could fly), so we expect not many young birds perished," said biologist Felicia Sanders, who leads the SCDNR Coastal Bird Program.

At least 500 downy pelican chicks remain on the high ground of the island where adult pelicans had nested later in the season. Many juvenile pelicans as well as migratory shorebirds are utilizing the newly formed sandflats to rest and forage, and for this reason, the seasonal closures remain in place with portions of the island closed to boat landing until Oct. 16.

After making landfall in Florida, Hurricane Idalia came across to the coast of South Carolina during the late afternoon hours of Aug. 30. This coincided with a full moon high tide at 8:24 p.m., which was predicted to be 6.9 feet in Charleston Harbor. With the associated wind and water from post-tropical cyclone Idalia, the tide in Charleston Harbor crested at 9.2 feet that evening. It was the fifth-highest peak tide on record for Charleston, just shy of the high mark during Hurricane Matthew in 2016 (9.29 feet) and Hurricane Irma in 2017 (9.92 feet).

Deveaux Bank Seabird Sanctuary was established to protect important habitat for nesting and migrating seabirds and shorebirds. Currently and historically, Deveaux supports thousands of colonial nesting waterbirds, such as royal and sandwich terns, black skimmers and egrets on its banks.

In many years, Deveaux Bank supports more nesting brown pelicans than any other site on the Atlantic coast, making it one of the most important islands in the region for pelican survival. In addition, declining migratory shorebirds, such as red knots, piping plovers and whimbrels, flock to Deveaux in need of rest and food at beaches that are free from disturbance, essential for their survival after long journeys. Birds utilizing Deveaux Bank are of high conservation concern, so the public is asked to please follow closures in place and no-dogs-allowed rules.

For more information about SCDNR Seabird Sanctuaries, please visit: SCDNR - Coastal Birds in South Carolina - Seabird Sanctuaries.

For additional information, contact Felicia Sanders at sandersf@dnr.sc.gov.