Blue Trevally

Interesting Info

• The Blue Trevally (Carangoides ferdau) is a gleaming silver-blue reef hunter that glides through tropical waters like a blade of light. When sunlight hits its scales, it flashes turquoise and steel-grey — perfectly camouflaged for life among coral and open sea.
• It’s a member of the trevally and jack family (Carangidae) — a group of lightning-fast swimmers known for their teamwork and power. Like its cousins, the Blue Trevally is built for speed, with a deep body, pointed snout, and forked tail designed to slice through strong currents.
• In Australia, it’s common from Shark Bay across the Top End to southern Queensland and the Coral Sea.
• Blue Trevallies patrol coral reefs, lagoons, and outer reef slopes. They’re often seen gliding above sandy channels or reef drop-offs, sometimes following rays or groupers to snatch up prey disturbed from the seabed.
• These active hunters feed on small fish, squid, prawns, and crabs. They often hunt in pairs or small schools, coordinating fast turns and surprise attacks with astonishing precision.
• Juveniles are silvery with faint vertical bars, often staying close to floating seaweed or debris for protection. As they mature, their markings fade, and the body transforms into a shimmering metallic blue-grey — the colours that inspired their name.
• Blue Trevallies can live for at least 15–20 years, a long lifespan for such a fast-moving reef predator.
• Spawning occurs offshore during the warmer months. Males and females release eggs into the currents, and the larvae drift freely before settling into shallow reef zones as juveniles.
• This species is sometimes confused with the Bluefin Trevally, but unlike that cousin, the Blue Trevally has a more elongated body and lacks the deep cobalt fin edges. Look closely — it’s sleeker and subtler, a master of reef disguise.