A virulent and fast-moving coral disease that has swept through the Caribbean could be linked to waste or ballast water from ships, according to research.
The deadly infection, known as stony coral tissue loss disease (SCTLD), was first identified in Florida in 2014, and has since moved through the region, causing great concern among scientists.
It spreads faster than most coral diseases and has an unusually high mortality rate among the species most susceptible to it, making it potentially the most deadly disease ever to affect corals. More than 30 species of coral are susceptible. It was found in Jamaica in 2018, then in the Mexican Caribbean, Sint Maarten and the Bahamas, and has since been detected in 18 other countries.
In Mexico, more than 40% of reefs in one study had at least 10% of coral infected by SCTLD, and nearly a quarter had more than 30%. In Florida, regional declines in coral density approached 30% and live tissue loss was upward of 60%.
Scientists have not yet been able to determine whether the disease is caused by a virus, a bacteria, a chemical or some other infectious agent, but the peer-reviewed study in the journal Frontiers in Marine Science supports the theory that ballast water from ships may be involved. Conducted in the Bahamas by scientists at the Perry Institute for Marine Science, it found that SCTLD was more prevalent in reefs that were closer to the Bahamas’ main commercial ports, in Nassau and Grand Bahama, suggesting a likely link between the disease and ships.