SCTLD Frequently Asked Questions

What is SCTLD and where is it?

Stony Coral tissue Loss Disease (SCTLD) is a new deadly coral disease that appeared on Florida’s reefs in 2014 and has now spread to several countries in the Caribbean.

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What is the cause of this disease?

Researchers have been unable to determine the cause and method of transmission. Evidence suggests that it is a bacterial pathogen that is transmitted by touch and water circulation (Aeby et al., 2019). There is presently no known cure for this disease.

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

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?

Our coral reefs have had a good foundation to fight disease based on the previous efforts of the DoE. This agency has been working on 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. The Cayman Islands also has very little pollution and run-off from the land. We are aware that Cabinet is now considering an increase in the management and protection of coral reefs and marine habitats to 46%.

The DoE will continue to monitor the spread of SCTLD and continue treatments on the north coast and inside the North Sound. In creating a DoE managed firebreak, we removed the three most highly susceptible species from a large area in the hope of slowing or stopping the disease. This was successful in slowing the disease however it has not stopped it. The disease has now jumped the firebreak and is progressing toward Seven Mile Beach. Given the rapid spread of the disease, we need to select and protect ‘priority’ reefs based on their vulnerability to the disease.

We are actively training volunteers on disease identification and how to use treatment options while expanding our citizen scientist reporting efforts to engage the public in helping us to identify diseased coral. We are engaging in regional and international collaboration, and our team has extracted over 250 samples for epidemiological research. The most effective treatment option available is to use Amoxicillin + Base2B. Our control study has seen a 100% success rate treating lesions on 80 highly susceptible corals however, reinfection of healthy-looking is possible. While efforts are being made to study and understand SCTLD, we will continue disease mitigation until alternative treatments become available.

Can we dive on the north side?

Yes….providing that procedures and protocols are followed:

    1. All diving or snorkeling on the same day should be done in the same geographical location
    2. Avoid monitoring and control sites: Penny’s Arch and Max’s Garden
    3. Disinfect dive gear
    4. Disinfect bilge water

How do I disinfect my dive gear?

Pathogens on dive gear may survive for extended periods and can be transferred among reefs on subsequent dives, and, potentially, transmitted to reefs internationally, unless your gear is disinfected. If you are diving or snorkeling anywhere in the Cayman Islands, and before travelling between Grand Cayman and the Sister Islands, please disinfect your gear.

Disinfect your gear in a 1% bleach solution for 10 minutes before diving or snorkeling in a new location ( You can also use sodium percarbonate (sodium carbonate + hydrogen peroxide) or ‘oxi’ type cleaners that contain it. Examples of best practices can be found here:


The following protocols from NOAA ( Credit: Athena Burnett/NOAA) should be used by all persons diving or snorkeling anywhere in the Cayman Islands.

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If you have any questions, please email

How do I disinfect my bilge water?

Please disinfect bilge water with sodium percarbonate (sodium carbonate + hydrogen peroxide):

    1. Before travelling between Grand Cayman and the Sister Islands
    2. If moving from the north side to the west or east side

Bilge Water Decontamination Video:

How can the public help?

The public can help by reporting suspected sightings of SCTLD, volunteering time and resources, and spreading the word about this disease.

If you see something, say something. If you suspect that coral is diseased, report this with your photos and location at:

Volunteer Time
We are seeking volunteers who are nitrox trained, have dive insurance (preferably DAN), have their own dive gear; with a minimum of 100 dives; and available at least 2 days per week for training and SCTLD search. If you meet these requirements, send an email to with the following information:

a) Full name:
b) Date of birth:
c) Photocopies of highest diving certification and nitrox qualification:
d) Photocopies of DAN insurance information:
e) Number of dives to date:
f) Days/Dates available to assist:
g) When you have your own dive gear:
h) Date of last dive:

Volunteer Resources
If you have resources to support the project such as a boat or staff, please send an email to with the following information:

a) Name of your company:
b) Contact details:
c) Number of boats offered:
d) Whether you can provide tanks and air:
e) Number and names of staff available:
f) The days/times/duration offered:
g) Whether compensation is required:
h) Which volunteers have a science background:
i) Which volunteers have coral identification skills:

Public meetings
Arrange a meeting with your watersports company, dive buddies, ocean conservation group, or any other group interested in protecting our coral reefs. We will do a short presentation and answer any questions that you might have.

Training Workshops
We can organise a training session so that you can learn to identify SCTLD and other coral diseases. This is helpful for person who are often in the water or who might be interested in volunteering.

Keep Updated
Follow us on social media to keep up-to-date with our team’s work. You can find us on Facebook, Instagram, and Twitter using @doecayman

Who do I contact for more information?

For more information, contact the Lead Coordinator for the SCTLD Response Project, Tammi Warrender at: or the SCTLD hotline at +1 (345) 926-0680.

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