Ciguatera fish poisoning is the most frequently reported non-bacterial illness associated with eating fish in the United States and the U. S. territorial islands. Ciguatera significantly impacts commercial and recreational fishing activities in the U.S. and worldwide. This first-ever, large scale coordinated monitoring study of ciguatera fish poisoning will explain factors that make this disease so prevalent and develop methods to predict future outbreaks.
Why We Care
Ciguatera fish poisoning disease (CFP) is the most common form of algal toxin-induced seafood poisoning in the world affecting tens of thousands of people annually. CFP is primarily caused by members of the bottom dwelling, dinoflagellate genus, Gambierdiscus. Gambierdiscus lives on the surfaces of corals and seaweeds which are grazed by herbivorous fish and invertebrates. Toxins produced by Gambierdiscus contaminate these marine animals and the carnivores that feed upon them causing toxins to move into the food chain. Eating tropical marine reef fish contaminated with Gambierdiscus toxins can cause CFP illness characterized by digestive and nervous system disorders in humans. Increasingly, CFP outbreaks are found globally but continue to most heavily impact tropical and subtropical island cultures that depend upon reef fish for sustenance. CFP outbreaks have proved impossible to predict and manage to date. This regional study, Ciguatera Investigations in the greater Caribbean region, or CIGUAHAB, will lead to predictive capabilities that will lessen the impacts of CFP illnesses by reducing exposure to toxins.
What We Are Doing
We are sampling coral, seaweed, and reef fish throughout the greater Caribbean region over five years to document Gambierdiscus diversity, distribution, physiology, and toxicity. Each year we intensively monitor at field sites in St. Thomas and the Florida Keys. We will sample less frequently on Gulf of Mexico oil rigs, in the Flower Garden Banks National Marine Sanctuary, along the Mexican coast, and in the Bahamas. Lab cultures of Gambierdiscus we collect will support genetic diversity, growth, and toxin production studies. We will analyze fish samples for CFP toxicity and determine toxin congeners that result from biotransformation. This work will allow the identification of key factors that control Gambierdiscus growth and toxicity and the design of computer models capable of predicting where and when CFP risks are greatest. CIGUAHAB leverages past U.S. Centers for Disease Control research in the U.S. Virgin Islands advancing monitoring in an area long impacted by CFP.
The CIGUAHAB project is part of the Ecology and Oceanography of Harmful Algal Blooms (ECOHAB). The project is led by Dr. Michael Parsons, Florida Gulf Coast University. Project partners include Dr. Donald Anderson and Dr. Mindy Richlen (Woods Hole Oceanographic Institution), Dr. Deana Erdner (University of Texas), Dr. Ron Kiene (University of South Alabama), Dr. Yuri Okolodkov (University of Veracruz, Mexico), Dr. Alison Robertson (U.S. Food and Drug Administration) and Dr. Tyler Smith (University of the Virgin Islands).
Benefits of Our Work
This project will provide critical advances in our knowledge of the ecology of Gambierdiscus and factors that control CFP outbreaks. The development of a model to predict how the alga responds to environmental conditions will enable new management strategies to be explored. Predictive tools will enable predictions of when and where outbreaks are likely to occur lessening human illnesses by reducing the exposure to the toxins that cause CFP.