The ciguatera organism works it's way up the food
chain in reef fish
. The larger the fish
, the more likely it is to be a carrier. Typically, the top of the food
chain is the Barracuda and should never be eaten. All of the above applies to areas where Ciguatera is known to exist.
Areas such as the Marquesas
(the first recorded poisoning when discovered by the Duke De Marquises in the 16th century) are notorious for ciquatera. It is also found in the Society Islands but not as prevalent as the Marquesas
. The Tuamotu's, in between, typically don't have it. Rumor had it that fish on one side of a pass would be infected while fish on the other side were safe to eat in the Societies. It has been known in the Hawaiian Islands usually when the bottom has been disturbed like in dredging for a harbor. There are many other areas where ciquatera is lurking.
Having said the above, we accidentally ate a 6' Barracuda (looked like an Ono to us but Ono don't have long spikey teeth) that we caught in the Marquesas and didn't get sick. We also saw locals and yachties who got sick from eating supposedly save reef fish. Don't count on local knowledge to keep you safe. About the only way to 'test' the fish is to feed it to your cat and wait for a 1/2 day or so to see if the cat is effected. Rather cruel but you don't want to get poisoned. Our policy was not to eat reef fish, no matter what the locals said, in areas that were known to be infected. It was pretty well known which Islands and areas were susceptible to poisoning so not difficult to to avoid getting poisoned.
Ciguatera poisoning is not fun. Symptoms range from severe flu to neurological problems. Nuerological symptoms like extreme sensitivity to cold or heat can hang on for a number of years. Though it is seldom fatal, a young girl off a cruising boat died when we were in Ahe in the Tuamotu's. She ate fish in Papeete just before they sailed to the Tuamotu's. They thought she just had a severe case of sea sickness
but it didn't go away when they anchored in the Lagoon
. Had to take her by boat to the nearest Island with a landing strip and fly her back to Hospital in Papeete. She died soon after reaching the hospital.
Pelagic fish like Ono, Mahi Mahi, Bonita, and Ahi are always safe AFAIK. Even though we typically caught Ono near the entrance to bays and anchorages
, they were always safe. The other pelagic fish, we typically caught farther out to sea. Fortunately, lobster weren't effected as they were a regular part of our diet.