Ciguatera poisoning is a debilitating affliction that can result in some pretty severe physiological changes and a suite of severe medical conditions — occasionally even death. The usual way for an individual to ingest ciguatoxins is by eating subtropical and tropical reef fishes. Some of the prime suspects in reef communities include large barracuda, groupers, morays, snappers, and other sizeable predators. Other fishes, including hogfishes and a variety of other popular food fishes, have also been implicated in ciguatera outbreaks.

Many explanations have been advanced for ciguatera poisoning, ranging from submarine copper deposits to ingestion, by fishes, of poisonous berries, and it has not been until very recently that a few scientists have discovered what appears the real mechanism. At the root of it all are dinoflagellates, producing ciguatoxins that are then magnified as they pass up through the complex food web of a coral reef. It's probable that human interference — as so often seems the case — may be responsible for increasing the severity and extent of ciguatera outbreaks by creating changes in reef structure that allow the algal hosts of the offending dinoflagellates more opportunity to grow. My own experience and the written and anecdotal accounts of many others indicate that local people, especially in areas where subsistence fishing provides the bulk of a person's protein intake, often possess extremely detailed knowledge of where to fish so as to avoid ciguatoxic fishes, a feat made more remarkable by the fact that occurrence of ciguatera can be very patchy even within a single reef area.

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