Monitoring and Interventions

In response to the disease outbreak, several groups are monitoring and trying new treatments and interventions to stop or slow the spread of stony coral tissue loss disease.

Monitoring in the Caribbean

SUBMIT A REPORT

To help track and better understand SCTLD in the Caribbean, we ask for your help in reporting observations by filling out an online survey form, which includes information on coral species affected, location, and photos. We are specifically interested in SCTLD reports or other unusually high reports of recent coral death.

We have improved and simplified the survey forms into a Basic and Detailed form (see below for descriptions). New to the form is the ability to add data on Coral Bleaching. The main difference between the two forms is the Basic form is simple and includes estimates of corals affected, versus the detailed form allows actual coral colony counts and more site information.

This simple survey form allows you to enter presence/absence data on corals affected by SCTLD and bleaching by coral species and estimates of corals affected, photos and site information. You can identify survey method used such as rover diver, bar drop, general observation, etc.

NEW combined SCTLD / coral bleaching survey data sheet can be used for basic or detailed surveys. This corresponds to the online data entry tool and tracking map. Click here or on image below to access.

This detailed survey form allows you to input quantitative data on coral species affected, colony counts (number of colonies affected) presence of stony coral tissue loss disease, presence of coral bleaching (fully bleached, partly bleached, pale), recent coral mortality, photos and site information. You can identify method used such as rover diver, bar drop, etc.

Watch this Video tutorial on the new Detailed Survey form.

Click on image below for video.

MONITOR

Monitoring of SCTLD outbreaks will likely require initial rover diver surveys to establish presence/absence and spatial extent followed by surveys (e.g., belt transects, quadrats, mosaics) to document the spatial extent, coral species affected and mortality rates.

Monitoring Priorities

Priority coral disease response activities include:

  • Monitor highly susceptible species like Meandrina meandrites (maze coral), Dichocoenia stokesii (elliptical star coral), Dendrogyra cylindrus (pillar coral), and Colpophyllia natans (boulder brain coral).
  •  Monitor colonies of large, reef building coral species like Orbicella (mountainous star coral).
  • Take photos of suspected diseased corals and submit your report using one of the survey links above with date and gps location.
  • For confirmed disease occurrences, monitor every few days/weekly to track fate of colonies, rate of transmission and spatial extent.
  • Evaluate and identify priority reef areas and priority coral colonies for intervention and treatments.

LEARN MORE

Given the potential for widespread areas to be affected, a multi-partner effort of managers, biologists and citizen scientists is suggested. To learn more about SCTLD, scientists and managers can train recreational snorkelers and divers to help properly identify SCTLD from other coral diseases and teach survey and investigation techniques.

DATASHEETS

Combined SCTLD / coral bleaching survey data sheet – English

Coral SCTLD Datasheet by Species Common Names – English

Response & Interventions

FLORIDA RESPONSE ACTIVITIES

In Florida, priority coral disease response activities include:

  • Coral disease investigation training on coral disease identification, ecology and investigation techniques.
  • Coral disease surveys and fixed site monitoring to document the spatial extent, mortality rates and species-specific impacts.
  • Strategic sampling and laboratory analysis to identify the presence of pathogens potentially responsible for the disease outbreak.
  • Data management and epidemiological analysis to analyze relevant datasets and determine what factors may influence disease progression.
  • Sampling plan and disease intervention workshops to determine priority data needs and potential management options to mitigate disease impacts.
  • Intervention experiments and field trials to assess the effectiveness of treatment techniques and prevent the further spread of disease.
  • Coral disease investigation training on coral disease identification, ecology and investigation techniques.
  • Coral disease surveys and fixed site monitoring to document the spatial extent, mortality rates and species-specific impacts.
  • Strategic sampling and laboratory analysis to identify the presence of pathogens potentially responsible for the disease outbreak.
  • Data management and epidemiological analysis to analyze relevant datasets and determine what factors may influence disease progression.
  • Sampling plan and disease intervention workshops to determine priority data needs and potential management options to mitigate disease impacts.
  • Intervention experiments and field trials to assess the effectiveness of treatment techniques and prevent the further spread of disease.

For more information on Florida’s monitoring and response efforts visit: www.floridadep.gov/fco/coral/content/florida-reef-tract-coral-disease-outbreak

FLORIDA INTERVENTION ACTIVITIES

In an effort to reduce the spread of disease and loss of live coral tissue, several laboratory and field trials have been done including topical applications of chlorine and amoxicillin, topical chlorinated epoxy, amputation of affected regions of diseased corals, and relocation of healthy regions of diseased corals. The results from efforts in Florida are summarized below and will be updated regularly. In Mexico, additional field intervention trials are ongoing and information will be posted when available.

In Situ Coral Disease Interventions in Florida

Summary of the Florida Department of Environmental Protection, Coral Reef Conservation Program, Final Report, Florida – FY 2018 In Situ Disease Intervention, Karen Neely and Emily Hower, Nova Southeastern University (2019).

Above photos show coral with SCTLD (top) and treatment efforts by researchers in Mexico (bottom) (Photos provided by M. Soto, HRI).

  • Amoxicillin treatments are much more effective than chlorinated treatments. This effectiveness is seen in summary analyses, but also when treatments among species (CNAT, OFAV, DLAB) are compared. But even then there was still up to 20% failure at 19 weeks.
  • The CoreRx Base 2b showed lower subsequent encroachment of external lesions, suggesting a better dissemination to adjacent tissue (halo zone).
  • Small patches (<5 cm, which might also represent newly diseased colonies) responded much better than large lesions.
  • Response to treatments is species-specific. Brain corals (particularly DLAB) respond poorly, while OFAV responds well.
  • Even the most effective treatments are acting only at the lesion level. New lesions continue to erupt and overtake treatments, leading to ongoing tissue loss as well as necessary frequent re-visitation to apply additional treatments. All corals needed more than one treatment.
  • Schedules for re-treatment and monitoring vary based on species and perhaps disease status. Epidemic zones and highly susceptible species require more frequent monitoring to determine effectiveness, and more frequent re-treatments to catch new lesions or repair broken treatment lines.

Bottom line: focus resources on large colonies of Orbicella spp. as they’re the most important reef-builders, best known responders to amoxicillin and also likely to be the largest local reservoirs of the pathogen.

Suggestions for future work:

  • Address whether species like OFAV that respond well to treatment would also respond well in epidemic or invasion zones would prioritize these corals before they experience significant tissue loss, and while lesions are still small might better respond to treatments.
  • Further comparisons of amoxicillin treatments with and without trenching or the application of clay to cover the treatments would elucidate the effectiveness of these additional measures.
  • A high priority research topic should be to address intervention at the colony or reef level, and management questions relating to this should be considered well in advance. Potential options may include antibiotic dosing by bagging or medicated feed, and could include probiotic application or phage therapy.
  • Reef-scale intervention may also be considered on small patch reefs by treating all lesions within an isolated region to determine whether the elimination of lesions in such an environment could have reef-scale consequences.

ADDITIONAL INFORMATION

Walker, B and A. Brunelle. 2018. Southeast Florida large (>2 m) diseased coral colony intervention summary report. Florida DEP & FWC. Miami, FL. Pp. 1-164.

Report Summary

“The purpose of this project is to perform disease intervention on previously-identified, large corals (including ESA-threatened-species) over two meters in diameter in SE FL identified with active disease. This includes restoring coral health by smothering diseased tissue, creating a “fire break” to arrest disease progression and covering the newly exposed skeleton with chlorinated epoxy. These activities are essential to save the largest, oldest, and most resilient corals in SE FL affected by disease.”