Each oyster in a cluster is used by succeeding generations. The cluster continues to grow as each new set occurs. Sometimes clusters reach a foot or more in thickness. The added weight of additional individuals tends to push the lowermost oysters into the mud where they eventually suffocate. Only the outermost oysters remain alive.
Harvesting is done by hand at low tide.
Oyster predators suffer more from exposure to the elements than do oysters. Therefore, intertidal oysters are subjected to less predation than oysters which grow subtidally. The blue crab, as well as other crab species, oyster drills, starfish and boring sponges cause mortality, especially among small oysters. Abundance of oysters in South Carolina has remained relatively stable in recent years, although populations are lower now than they were in 1900. Declines, in part, have been related to increased siltation resulting from alterations in stream flow, overharvesting, and physical distubances to the shell bed.