Disease outbreak investigation on the reefs of Kauaʻi
PRINCIPAL INVESTIGATOR: Greta Aeby
Co-INVESTIGATORS: Sean Callahan
Graduate Trainee: Christina Runyon
Outbreaks of coral disease can kill large numbers of corals and are occurring more frequently on the reefs of Hawaiʻi. In 2012, an Eyes of the Reef member reported a high number of rice corals (Montipora sp.) with progressive tissue loss. This project was initiated to determine the cause of the disease and how widespread the problem might be on the reefs of Kauaʻi. The disease was found to be black band disease (BBD), which occurs on reefs worldwide but this was the first discovery of BBD in Hawaiʻi. We found BBD on corals at 23 sites around Kauaʻi exclusively on the north and east sides of the island. Tagged colonies showed BBD to be a progressive disease that resulted in complete mortality of 28% of the corals within 10 months. A method of disease treatment, lesion occlusion, was successful at stopping the disease except on corals with large established lesions. Presentations on the results of this study were given to resource managers, interested community members and at academic meetings. BBD has not been found anywhere else in Hawaiʻi despite extensive surveys. Future work includes examining the relationship between disease occurrence and environmental variables to help explain why BBD is found exclusively on Kauaʻi.