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Photo copyright Tim Nicholson.
Trevally
Taken at Elphinstone, Egyptian Red Sea.
Trevallys are large silvery fishes with forked tails.
They are fast-swiming predators of the waters above the
reef and in the open sea.
The species we are concentrating on today, the Bluefin
Trevally, is found in the Red Sea and Pacific Ocean. It
is distinctively coloured, being the only trevally with
electric blue fins and blue speckles on a gold or green
background.
This fish can be as large as 1 metre, but you normally
see individuals smaller than this. They range from the
shallows to the depths, usually singly but you may see
a trevally small school.
Bluefin Trevally are currently being trialled for
aquaculture in the Pacific. But if eating this fish
beware of large specimens: they become toxic when over
50 cm.
The fish feeds on other fish and sometimes crustaceans.
It launches high-speed attacks, typical of large
transient predators. However, when feeding on spawning
fish it also ambushes its prey, attacking from a hiding
place. This is unusual in such a fast-swimming fish.
During ambush hunting, it adopts a dark coloration and
defends a section of the reef.
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