Stony Coral Tissue Loss Disease Monitoring and Action Plan

Stony coral tissue loss disease (SCTLD) was first seen in Florida in 2014 and since, other locations in the Caribbean have identified similar signs of the disease on their reefs. As of August 1, 2019, the disease has been confirmed in the Caribbean countries and territories of Jamaica, Mexico, Sint Maarten, the Dominican Republic, the U.S. Virgin Islands (St. Thomas), the Turks and Caicos Islands and Belize. The disease is characterized by its high mortality rate. Affected coral colonies present lesions that rapidly expand outward and can ultimately kill all live tissue.

The disease affects over 20 coral species of hard corals (Table 1) and is contagious between individual corals and among coral species. Highly susceptible species, such as the pillar coral (Dendrogyra cylindrus) are often the first to show signs of the disease, with the species of intermediate and low susceptibility showing signs thereafter. It is water-borne and can also spread through contact. Research to determine the pathogen(s) involved is ongoing and although one is yet to be determined, applications of the antibiotic amoxicillin have curbed disease progression in both laboratory and field experiments. Identification of SCTLD is based on a multi-factor field diagnosis based on the characteristics such as species affected, the order in which species are affected, and
prevalence of affected colonies within a given area.