Tracking the Fate of Bleached Corals Following the 2015 Thermal Bleaching Event in Maui, HI

As thermal bleaching events are expected to increase in frequency for many coral reefs around the world, the 2015 bleaching event in the Main Hawaiian Islands was only the second ever recorded archipelago-wide bleaching event. Understanding baseline changes in the reefs after a bleaching event allows local managers to make informed decisions to support recovery of reefs. Using benthic imagery taken just days after the peak of bleaching and at 6 month and 1.5-year intervals, this project followed five of Maui’s most abundant coral species through a post bleaching time series analysis. Beginning with an assessment of bleaching severity, the fate of individual corals on two Maui reefs was tracked to understand if corals recovered, suffered partial mortality, or suffered full mortality. Corals from the Olowalu site showed a trend toward reduced size class of corals after the bleaching event while corals from the Kahekili site showed a trend toward larger size class of corals after the bleaching event. Overall at both sites, corals that bleached less severely recovered more healthy tissue between 2015 and 2017