Climate Change Increases Risk of Fish Poisoning, Says New Study

One likely effect of ongoing ocean warming, say federal scientists: An increase in the likelihood of ciguatera fish poisoning in the southeastern United States

A new NOAA study is forecasting an increase in ciguatera fish poisonings from fish caught off the U.S. Southeast and Gulf coasts as the result of "rising global ocean temperatures due to climate change."

A definitive ciguatera article in Sport Fishing magazine in 2011 identified ciguatera as "a very scary disease .... one of the most common ailments from eating fish and considered a global health concern [that] may be getting worse."

People are afflicted by this long-lasting, painful disease when they eat tropical marine reef fish that are contaminated from algae containing neurotoxins. Larger predators, higher on the food chain, can accumulate the toxins which unfortunately are tasteless and odorless and cannot be removed by freezing or cooking.

Ocean warming might in effect extend the range of ciguatera and mean larger and longer -lasting blooms of harmful algae.One possible upside: In tropical areas already very warm, still higher water temperatures could prove too hot for Gambierdiscus, the ciguatoxic algae, and actually inhibit blooms.

While this study looked at the southeastern United States, ciguatera is a global disease, and similar geographical extension may be occurring worldwide.

The study — "Effects of ocean warming on growth and distribution of dinoflagellates associated with ciguatera fish poisoning in the Caribbean," in the journal Ecological Modeling — does not recommend changes in fish consumption. Indeed, the risk of contracting ciguatera from eating any fish remains very low. However, the severity of the disease leads many to shy away from eating larger reef-dwelling predators.

More about the disease, the risks and species particularly likely to carry it can be found in Sport Fishing's article, The Perils of Ciguatera.

Risky Business

Inviting a huge black grouper — like this one caught off Brazil — to dinner would be a risky proposition. This Sport Fishing article explains that such large reef predators can concentrate harmful amounts of ciguatoxins.Photo by Capt. Antonio "Tuba" Amaral