Lesion recovery of two scleractinian corals under low pH conditions: Implications for restoration efforts

Some coral restoration efforts are involving cultivation of coral microfragments in land-based pools under controlled conditions until they reach viable size for outplanting. However, gaps in knowledge with these efforts include effects of changing pH on regeneration rates of tissue lesions and other physiological responses on different size fragments. To address this, two fragment sizes of Porites porites and Porites astreoides were artificially inflicted with lesions and incubated in two pH treatments to follow effects on recovery and physiological performance. Recovery was significantly reduced at reduced pH for P. porites in both fragment sizes; while recovery of P. astreoides was reduced only in the larger fragments. Different responses were also seen for Symbiodinium density and total protein with pH and fragment size. Effects on lesion recovery rate from pH and fragment size were species specific and may be related to morphology and/or energetic constrains.