Acropora palmata is a threatened, reef-building coral native to Florida, the Bahamas, and the Caribbean. Once prevalent throughout its range, A. palmata has suffered extreme losses (>90%) in the past decades attributed largely to bleaching, disease, and hurricanes. These corals thrive in shallow regions with high wave action and are extremely susceptible to storm damage; however, their ability to reproduce asexually when storm fragments attach themselves to a nearby substrate can provide resiliency when exposed to storms of low frequency and intensity. In September, 2017, catastrophic hurricanes Irma and Maria severely impacted the populations of A. palmata in St. John, USVI, with many mature colonies being severely damaged or destroyed. Teams of student-researchers have been surveying populations in Salt Pond Bay, St. John, USVI for the past three years as a part of a field course from Georgia State University. This provided us with a unique opportunity to investigate hurricane impacts on coral population health and recovery. Underwater images of A. palmata taken six and eighteen months after the 2017 storm events are being visually analyzed, placed into morphological stage classes, and evaluated for surface area using CPCe. Preliminary results indicate a twofold increase in surface area of the A. palmata colonies assessed. Many colonies and fragments have transitioned from the crust stage observed in 2018 to measurable early branching forms in 2019, a sign of transition into the colony (mature) stage. These results may indicate that A. palmata in this study are recovering at a faster rate than those predicted by existing models, particularly regarding a hurricane of Irma’s intensity. As storm intensity and frequency in the Caribbean are predicted to increase with increasing sea surface temperatures due to global climate change, understanding the recovery rate of these threatened corals is critical to developing comprehensive conservation and management plans.
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