Читать книгу Diving Indonesia Periplus Adventure Guid онлайн

123 страница из 170

Ciguatera Poisoning

Ciguatera is a toxin produced by a tiny dinoflagellate alga, Gambierdiscus toxicus. The alga itself is harmless enough, living around rocks, sea-grass and filamentatious algae. The quantities of poison in each organism are minute.

But the dinoflagellates are eaten along with the algae in which they live by herbivorous fish and invertebrates. These herbivores are then eaten by larger, carnivorous fishes, and these are in turn are eaten by even larger, and more voracious predators. Since the ciguatera is not broken down, it concentrates in the tissues of these higher order predators.

A human being who eats a ciguatoxicfishwill experience numbness in hands and feet, disorientation, weakness, vomiting, diarrhea, shortness of breath and even cardiac arrest. The poison is very serious. People have died from ciguatera and there is no available cure.

The greatest danger comes from fish at the highest levels of the food chain: snappers, groupers, large jacks, barracuda, some trigger-fish and moray eels. For reasons not well understood, certain species are morefrequentlyciguatoxic than others: particularly the red snapper (Lutjanus bohar), and also the giant moray (Gymnothorax javanicus), the saddleback grouper (Plectropomus laevis) and the giant grouper (Epinephelus lanceolatus).