Coral reef rehabilitation through transplantation of staghorn corals: effects of artificial stabilization and mechanical damages

In order to develop and test a low-cost method of coral reef rehabilitation, the staghorn corals Acropora muricata and A. vaughani were transplanted to a shallow site with unstable substrate. To avoid abrasion, dislodgement and transport due to water movement, the transplanted corals were tied to string sections, which were connected at the seabed to form a grid. This created stability and improved the survival of the corals. The average increase in weight of live coral over 1 year was 56%, eight times more than the control treatment with unattached coral branches. This difference was mainly due to a reduced partial mortality among smaller coral fragments in the stabilized treatment. Survival was positively related to initial size among the loosely placed coral branches, whereas the attached treatment showed a negative relation between size and relative increase in weight of the surviving parts of the coral branches. Coral fragments were not significantly affected by severe physical damage simulating the effects of handling.