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This study describes the health status of Siderastrea siderea in Little Cayman before, during, and after the 2015 Caribbean-wide elevated temperature anomaly. Colony color was used as a proxy for health during snorkel and scuba surveys of shallow (<2 m depth) and deep (6 -16 m depth) reefs. Baseline demographics indicated that 6% of this species were pale or blue pre-disturbance. When seawater temperatures exceeded 30.5˚C, S. siderea were early indicators of reef stress and among the first corals to bleach. Depth and site resilience did not significantly impact temperature susceptibility; however, smaller colonies (<200 cm 2 surface area) were more likely to change color than the larger size classes. Little Cayman's S. siderea were capable of surviving large-scale (>80%) bleaching: mortality was observed for only one colony. Resilience rates varied considerably: one-third of the impacted population returned to the normal brown color within two months, one-third required 3 -9 months to recover, and the fates of the remaining one-third remain to be determined. If the return to normal color is indicative of resistance to reef disturbances, S. siderea may be among the "winning" coral species following elevated temperature anomalies which are predicted to occur with increasing frequency and severity as a result of climate change.

Individual massive coral colonies, primarily faviids and poritids, from three distinct assemblages within the southeastern Arabian Gulf and northwestern Gulf of Oman (United Arab Emirates) were studied from 2006–2009. Annual photographic censuses of approximately 2000 colonies were used to describe the demographics (size class frequencies, abundance, area cover) and population dynamics under “normal” environmental conditions. Size class transitions included growth, which occurred in 10–20% of the colonies, followed in decending order by partial mortality (3–16%), colony fission (<5%) and ramet fusion (<3%). Recruitment and whole colony mortality rates were low (<0.7 colonies/m2) with minimal interannual variation. Transition matrices indicated that the Arabian Gulf assemblages have declining growth rates (λ<1) whereas the massive coral population is stable (λ = 1) in the Gulf of Oman. Projection models indicated that (i) the Arabian Gulf population and area cover declines would be exacerbated under 10-year and 16-year disturbance scenarios as the vital rates do not allow for recovery to pre-disturbance levels during these timeframes, and (ii) the Gulf of Oman assemblage could return to its pre-disturbance area cover but its overall population size would not fully recover under the same scenarios.