Header & Organization Information

STONY CORAL TISSUE LOSS DISEASE

Sub-title: Mitigating the Spread by Ballast Water Management

Logos present: USCRTF (United States Coral Reef Task Force), Florida Department of Environmental Protection Coral Reef Conservation Program, and Sea Grant Florida.

Central Informational Box: What is Stony Coral Tissue Loss Disease?

• Stony coral tissue loss disease (SCTLD) is a highly destructive disease that impacts important reef building coral species.
• Once disease signs appear, corals can die quickly in just weeks to months.
• SCTLD has only been observed in the Atlantic/Caribbean, where outbreaks have occurred sporadically and often near commercial ports, suggesting ships may play a role in transporting the disease.
• Susceptibility of corals to SCTLD in other regions is not yet known.

Four Core Ballast Water Management Practices

1. Avoid Uptake in Affected Areas (Marked with a Red X)

• Ballast water is seawater held in tanks and cargo holds of ships that provides stability and maneuverability during a voyage.
• When ships uptake seawater in their ballast tanks, they also take on microorganisms, such as bacteria and viruses, present in that water.
• Scientists don’t know what causes SCTLD, but currently believe microorganisms are involved.
• Ballast water sourced in regions impacted by SCTLD could potentially spread SCTLD to new regions.
• Visual graphic description: A diagram of a large cargo ship next to a magnified circle showing bacteria or virus cells under water. An arrow labels these cells as “SCTLD”.

2. Exchange of Ballast Water in the Open Ocean (Marked with a Green Checkmark)

Ballast water exchange in the open ocean (i.e., > 200 nautical miles from shore) replaces potentially contaminated ballast water with safer open ocean water.

Visual graphic description: A diagram showing a cargo ship in mid-ocean with dual arrows pointing down and up, indicating water discharging and flushing out from the vessel hulls.

3. Use a Ballast Water Management System (Marked with a Green Checkmark)

• The use of an approved ballast water management system, such as chemical treatment or UV radiation, can reduce the number of microorganisms in ballast water.
• While simulated ballast water experiments indicate that UV-treatment alone is ineffective at preventing SCTLD transmission, more research is needed to determine whether other systems can help prevent disease transmission.
• Visual graphic description: A diagram showing a vessel with a magnified circle illustrating a water filtration tube radiating purple UV-treatment rays onto passing microorganisms.

4. Do Not Discharge Ballast Water Near Coral Reefs (Marked with a Red X)

SCTLD is known to spread to healthy corals through contaminated seawater and sediment.

Visual graphic description: A diagram showing a ship discharging water directly over a coastal marine ecosystem filled with diverse corals and a fish swimming near the seabed.

Footer & Web Resources

For more information on SCTLD please visit:

• https://noaa.gov
• https://agrra.org