Hovering low over Tennessee Reef off Long Key earlier this month, Mike Parsons squeezed the trigger of his spear gun and drilled a black grouper.

As tasty as the fish would have been, it was destined not for the grill but for the lab.

Parsons, an FGCU professor of marine sciences, is lead investigator of CiguaHAB, an international team of scientists conducting a five-year project to investigate conditions that lead to outbreaks of ciguatera fish poisoning. The $5 million study is financed by the National Oceanic and Atmospheric Administration.

CiguaHAB researchers will work in the Keys and St. Thomas, U.S. Virgin Islands, for the full five years of the project and for two years at oil rigs in the northern Gulf of Mexico, the Flower Gardens National Marine Sanctuary, the Bahamas, and Veracruz, Mexico.

Participating in the project are the University of Texas Marine Institute, University of South Alabama, University of the Virgin Islands, University of Veracruz, Woods Hole Oceanographic Institute and the U.S. Food and Drug Administration Gulf Coast Seafood Laboratory on Dauphin Island, Ala.

Ciguatera, the most common toxic seafood poisoning in the world, is caused by various species of single-cell Gambierdiscus algae, which produce a powerful neurotoxin called ciguatoxin and live on bottom-dwelling macroalgae.

Ciguatoxin works up the food chain when Gambierdiscus cells, sometimes called Gambies, are ingested along with their host algae by herbivorous fish and invertebrates, which are then eaten by predatory fish.

People who eat ciguatoxin-laced fish and invertebrates can come down with ciguatera poisoning. Fish known to carry ciguatoxin include barracuda, jacks, snappers, groupers, hogfish and triggerfish.

Ciguatera symptoms include vomiting, diarrhea, abdominal cramps, blurred vision, numbness and cardiovascular problems.

Before coming to FGCU in 2007, Parsons studied ciguatera at the University of Hawaii.

“We did surveys every month, collecting environmental data and looking at Gambierdiscus abundance,” Parsons said. “We noticed seasonal patterns. We were getting the highest numbers of Gambies in the early summer. read more…