Day Shift

Bluefin TrevallyBluefin Trevally
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Actinopterygii Family: Carangidae Genus: Caranx Species: melampygus
Scientific name: Caranx melampygus
Common name: Bluefin Trevally
Hawaiian name: Blue Ulua

Trevally is a wide–ranging species found around tropical latitudes across the Indo-Pacific to the depth of some 600 feet.

The Bluefin Trevally or Crevalle-jack gets its common name from the electric blue coloration to its dorsal, anal and caudal fins. Speckles of blue-black spots cover its back.

This is one of the few remaining reef-associated pelagic (open water) predators still commonly found around Turtle Reef, since most of the larger predators have been removed by overfishing. They are usually found singly or in small groups and often around reefs searching for targets of opportunity. They hunt actively over the reef in the shallows during high tide. The young may often be found close to the reef flat, near shore or in estuaries.

The Blue Trevally reproduce during summer months in Hawaii and usually at night when male and female individuals gather to cast their spawn into the open water to be carried away in the currents.

Ciguatera Poisoning
While Trevally may attain maximum lengths of a little more than three feet, by the time they have attained half that size they are often identified as a source of ciguatera poisoning. Ciguatera poisoning is associated with some 400 species of predatory fishes that live within the latitudes from 35N to 35S. Caused by the metabolites of various dinoflagellates (one-celled phytoplankton group of species), these varieties of closely-allied toxins accumulate in the food web to sub-lethal concentrations. When consumed by people the poisons cause a number of neurological responses, such as nausea, vomiting, diahorrea, numbness and headaches.

These toxins appear to be resistant to metabolic breakdown and are also heat resistant, so slow cooking does not detoxify them. There are no quick fixes to ciguatera poisoning although there are a few medicines that may help.

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