Bluefin Trevally (Caranx melampygus) lives in coral reefs across Indo Pacific. It feeds on fish and crustaceans. Its conservation status is Least Concern.
Fascinating facts about the Bluefin Trevally
- At just under five feet long and weighing as much as a small adult, the bluefin trevally can reach a maximum known length of 117 cm (46 in) and a weight of 43.5 kg (96 lb), yet individuals larger than 80 cm (31 in) are rare. Its early growth is rapid: 194 mm in the first year, 340 mm in the second, and 456 mm by the third.
- Adult bluefin trevallies are almost pure fish eaters, two Hawaiian studies found fish made up over 95 % of stomach contents by weight. By contrast, juveniles in Hawaiian estuaries eat crustaceans almost exclusively, with crustaceans constituting 96 % of gut contents numerically and fish only 4 %. Calculations suggest each adult swallows about 45 kg of fish per year, making it one of the most efficient predators on coral reefs.
- While juveniles linger in shallow bays, adult bluefin trevallies patrol deeper waters, often down to 183 m, favoring outer reef slopes, atolls and bomboras. Their range stretches across the tropical Indian and Pacific Oceans, from East Africa to Central America, covering four continents and countless islands. This breadth of habitat and depth tolerance lets the species exploit a wide array of prey, from coral lagoons to offshore drop-offs.
- Bluefin trevallies start life in tight schools, then shift to a solitary lifestyle with a defined home range as adults. Yet they can still gather for spawning or coordinated hunts, using the reef-produced chemical dimethylsulfoniopropionate (DMSP) to synchronize movements. Long-term tracking shows individuals may roam up to 10.2 km over several months, a far greater range than their giant trevally cousins.
- Bluefin trevallies hit reproductive maturity when they are only 30-40 cm long and about two years old, then become prolific multiple spawners. In captivity they can spawn up to eight times a year, dumping as many as six million eggs annually.
Sources
Every fact above was checked against these pages, and kept only where one of them states it.
At a glance
RangeIndo Pacific
HabitatCoral reefs
DietFish and crustaceans
About the Bluefin Trevally
In the warm, sun-drenched waters of the Indo-Pacific, the Bluefin Trevally glides with effortless elegance, its iridescent scales flashing like polished steel as it navigates the coral reef's labyrinthine passages. With a powerful tail and angular fins, it propels itself through the waves with a fluid, almost serpentine motion, its bright blue fins slicing through the turquoise depths like a hot knife through butter. As it patrols its domain, the Bluefin Trevally exudes an air of confident, unhurried dominance, a true monarch of the reef.
Hear the Bluefin Trevally, and 4,400+ more
Real recorded sounds, 11 nature games and a free Daily 5, 1v1 quiz duels, conservation wins and a safe Kids mode. Free on Feravox.
