Abstract Summary
Many factors go into decisions of where and what species to use for restoration, including reef-protection status, presence of live corals, historic coral success, and environmental conditions at sites being considered. We report on a study, started in 2009, measuring coral-calcification rates at six outer-reef tract sites in the Florida Keys, U.S.A. To date, we have measured the growth of Siderastrea siderea, Orbicella sp., Porites astreoides, Acropora cervicornis, and A. palmata by monitoring buoyant weight of corals for two-year periods. Generally, calcification rates were highest at the most remote site in Dry Tortugas National Park compared to the other 5 sites, and partial mortality was highest at sites in the Middle Keys, indicating that local conditions may modulate the success of restoration. Calcification rates on a planar-surface (“canopy”) basis (mg cm-1 day-1) were 1.5 for Orbicella sp., 2.7 for S. siderea, 3.3 for P. astreoides, 4.7 for A. palmata, and 5.8 for A. cervicornis. The estimates for Orbicella sp. and P. astreoides are likely low because of high-temperature stress during the summers of 2014 and 2015, respectively. An additional experiment showed that grow-out methods (“tree” vs. “block”) affect the robustness of A. cervicornis outplants and that there is likely a genetic basis for differential calcification rates. Our study suggests that achieving restoration goals for ecosystem services like shoreline protection and habitat provision requires matching species selection with physical-site considerations, and we suggest shifting more effort to restoring A. palmata.
