What does SCTLD look like?

SCTLD presents with focal or multifocal lesions. It is characterised by a rapid progression (up to 4cm per day). A bleached margin precedes the lesion.

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How does it affect our reefs?

SCLTD affects 25+ species of hard coral and has rapid tissue mortality and colony death. Once a coral is infected by SCTLD and begins to lose live tissue, it is likely that the colony will die within weeks to months with a 60-100% mortality rate (Precht et al. 2016).

SCTLD has a high transmission rate and affects a large geographic range. It is active year-round and can remain present for multiple years. The loss of coral density and species diversity affects overall coral reef health and can have catastrophic impacts on the ecosystem services that they provide (e.g. tourism, coastal protection, food, and recreation, etc.).

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What is the DoE response?

The Department of Environment has been facilitating the responsible management and sustainable use of the natural environment and the natural resources of the Cayman Islands since 1984. For almost 35 years, there has been some historical protection for our reefs through our Marine Parks Regulations.

After the confirmation of SCTLD in June 2020, the DoE held a meeting with watersports and dive operators on the 16^th October to update persons in the industry about the nature of this disease and DoE’s response, to request the public’s assistance in reporting any possible disease sightings, and to request that dive sites in diseased areas be avoided. The DoE held an update meeting on the 26^th February 2021 for all watersports and dive operators given that the disease had progressed beyond the DoE’s managed firebreak.

Despite efforts to stop the spread by removing sick corals, closing dive sites, disinfecting dive gear, and even applying experimental antibiotic paste to sick corals, SCTLD spread completely around Grand Cayman within 18 months.  Once SCTLD lesions are visible, corals are already infected so the various methods developed to treat the disease are ultimately ineffective at stopping the spread. This conclusion is supported by laboratory results from other coral researchers around the region dealing with the devastating effects of SCTLD. 

Though the spread of the disease could not be contained, best practices were successful in delaying transmission to Little Cayman by around 5 years. Efforts therefore remain focused on preventing the disease from spreading to Cayman Brac by continuing to promote the isolation of dive and snorkel gear to home islands and the disinfection of gear and boat bilge water.