In South Carolina, research has shown that the oyster (Crassostrea virginica) population is limited by the availability of hard substrate suitable for settlement. In recent years, the SCDNR has experimented with alternative substrates. A cement-coated crab trap method has proven to work extremely well at recruiting oysters. The SCDNR collects abandoned and donated crab traps and coats them with a thin layer of cement in order to create a hard substrate that larval oysters require for settlement, recruitment, and growth.
In the current project a potential method of introducing a larger-scale, intentionally fabricated, and more cost-effective structure, using cement-coated mesh materials was evaluated as a viable option for future oyster reef restoration by private residents. Thirty modified crab traps were deployed in the spring of 2016 at each of the two sites; the Ashepoo-Coosaw Cut in the ACE Basin NERR and the Chechessee River in Port Royal Sound. This created 480 square feet of new reef surface and served to increase oyster reef habitat in these watersheds. This was performed by SCDNR researchers, but would be feasible by an individual home owner wishing to adopt this strategy to create a living shoreline adjacent to his/her property to address erosion concerns, as an alternative to a bulkhead or seawall. Installation of the reef structures required manual efforts but no machinery. One person could easily pick up and move a cement-coated modified crab trap.
Oyster larvae settled onto and attached to the modified traps at both the ACE Basin and Port Royal sites showing that they work at attracting larval oysters. Continued monitoring of these structures will better inform researchers and interested homeowners as to their effectiveness to serve not only as reef habitat but also to support shoreline protection as living shorelines.