Award: IOS-1728002

Corals are threatened by diseases globally, and understanding coral disease is key to protecting coral reefs. Diseases are a major cause of coral mortality, yet there is surprisingly little information on the causes and progression of diseases in corals. Currently, there is a widespread coral disease outbreak occurring on the reefs of Florida that has already resulted in massive die-offs in multiple coral species. The severity of the outbreak of tissue loss disease affecting multiple species of corals and extending across most of the Florida Reef tract is unprecedented in the history of the study of coral reefs around the world. The high number of species affected, amount of coral loss, and spatial and temporal extent of the disease illustrate how devastating disease can become. Our studies found that the current disease affecting Florida?s reefs can be transmitted between coral fragments by direct contact and through the water column, and it can be transmitted to multiple species of corals. A therapeutic diagnostic approach using antibiotics halted the disease, suggesting it is a bacterial infection. Studies to identify the specific bacterial pathogen are still underway. We also examined potential methods of coral disease treatment using beneficial bacteria (probiotics). We found some of the bacteria on healthy corals can kill or inhibit the growth of known or suspected bacterial pathogens. We are currently testing the ability of these potential probiotic bacteria to protect coral from disease or slow the disease down. Diseased colonies were tagged in July 2017 and were followed through time to determine how virulent the disease was on coral colonies. After 11 months, 3 out of 20 Montastraea cavernosa colonies died and all others had some degree of tissue loss. However, some of the corals outlived the infection and are currently disease-free. We will continue to monitor these corals for disease re-occurrence or recovery. The combined efforts of multiple researchers and agencies, addressing different components of the disease outbreak, has provided much needed answers to questions concerning marine diseases, which will likely be applicable not only to the Florida coral reefs but to coral diseases world-wide. Gaining this much understanding of the ecology of this coral disease, so quickly, illustrates how it is critical to study coral disease from the ecological to the molecular level in a team effort. Furthermore, this project provided the next generation of marine scientists the training and tools to combat coral diseases in the future. This research will be beneficial to those who rely on coral reefs as a resource for food, recreation, and coastal protection. Our research also provides these answers to the coral reef resource managers struggling to contain this current disease outbreak in Florida. We gave training workshops for Florida coral reef managers and marine biologists on coral disease, bringing them up to speed in dealing with this current catastrophe. Reports were regularly provided to managers to assist them in decision-making for disease management. Our prior experience in in-situ disease treatment was shared, allowing managers to start to develop the capacity to save some of the iconic large corals in Florida. Last Modified: 10/02/2018 Submitted by: Valerie J Paul