Beaufort Terrapin Project

The Lowcountry of South Carolina is home to one of the most distinctive reptiles in the world: the diamondback terrapin (Malaclemys terrapin). The only turtle that lives exclusively in saltmarsh estuarine systems—a habitat that is abundant in Beaufort County—the diamondback terrapin is truly a gem of the marsh. Yet across much of its range, populations have declined markedly. Historically, overharvest for human consumption drove severe reductions, and today ongoing declines are largely associated with habitat loss and alteration, blue crab trap bycatch, and road mortality of nesting females.

In response to these concerns, the Center for Biological Diversity has petitioned NOAA Fisheries to list the diamondback terrapin as Endangered under the U.S. Endangered Species Act. The species is currently categorized as Vulnerable by the IUCN Red List of Threatened Species, reflecting rangewide conservation concern. In South Carolina, where this project takes place, the South Carolina Department of Natural Resources identifies the diamondback terrapin as a high‑priority species in its State Wildlife Action Plan. Taken together, these designations underscore the need for long‑term population monitoring in strategic locations to understand trends and inform management in the face of ongoing threats.

The Beaufort Terrapin Project began in 2024 in tidal creeks around St. Helena Island. Modeled after a long‑term monitoring program on Kiawah Island, the project uses mark–recapture methods to assess a terrapin population adjacent to a busy roadway in an area experiencing increased coastal development and boat traffic. Sampling occurs three times per year, providing a seasonal snapshot of this focal population. The mark–recapture effort is paired with a road mortality survey during the nesting season, designed to quantify the frequency and spatial distribution of female terrapins killed while crossing an adjacent road. These road surveys are patterned after similar efforts conducted on Tybee and Jekyll Islands in Georgia, allowing for comparisons across coastal systems.

This project is coordinated in partnership with the Port Royal Sound Foundation, Turtle Survival Alliance, and the University of South Carolina Beaufort. Additional participating organizations include the South Carolina Department of Natural Resources (SCDNR), Fripp Island Nature Center, South Carolina State Parks, and Georgia Southern University. Together, these partners are working to generate the baseline data needed to conserve diamondback terrapins in the Beaufort County region.

Read more about the Beaufort Terrapin Project: