In May 2012, oyster castles were installed near a U.S. Army Corps of Engineers, Charleston District disposal area south of the Isle of Palms. The purpose of this pilot project was to assist in the prevention of erosion and benefit the natural environment by establishing habitat and encouraging oyster recruitment. Since the installation, the District’s contractor, Aerostar Environmental, has visited the site quarterly throughout the first year to monitor the progress of the castles and the surrounding area.
Each inspection has shown positive growth. There has been a 97 percent growth rate in oyster shell height from 15 millimeters at the first visit to 29 millimeters at the second. However, due to their growth in height, there has been a decrease in the number of oysters per square meter. Spartina grass and sediment elevation behind the castles has increased by more than 3.5 inches, promoting bank stabilization and habitat structure formation.
District employees joined Aerostar for the fourth quarter site visit on June 21, where evidence of other aquatic species was observed, such as different species of crabs, fish and snails, as well as signs that birds had been feeding on the oysters. These castles have not only begun to protect the shoreline, but have established a habitat for many other species besides the oysters.
“We hope that the positive results obtained from this oyster pilot project will encourage support for more opportunities to protect our shorelines,” said David Warren, project manager. “The project will also enhance local species population growth, which will benefit the Atlantic Intracoastal Waterway’s ecosystem.”
After hearing of the success of The Nature Conservancy’s oyster program in Cape Romaine, the District thought this was an exciting, low-cost solution for erosion control and oyster restoration. TNC is pursuing the installation of the castles at James Island County Park.
“We used volunteers to build human chains for loading and unloading the blocks, stacking the blocks, and ultimately building a reef about 60 feet long by 3 feet wide,” said Joy Brown of TNC. “This promotes oyster substrate growth and animal species population growth.”
The continuation and promotion of oyster castle installation will offer benefits to the environment for years to come.