Bioerosion can be important to the configuration and destruction of coral reefs. Echinoids as grazers and burrowers can contribute significantly to coral reef erosion. Studies done on the turnover of gut contents of the two major burrowing echinoids on Enewetak atoll (Echinometra mathaei and Echinostrephus aciculatus) show a range of total CaCO2 erosion by both species from 80-325 g m-2 y-1....