Bluespotted Trevally

Interesting Info

• The Bluespotted Trevally (Caranx bucculentus) is a shimmering silver jack scattered with bright blue spots — like it’s been splashed with confetti!
• It grows to about 66 cm (26 in) long and around 5 kg (11 lb), though most are smaller, averaging 40–50 cm (16–20 in).
• In Australia it occurs across the tropical north, from Exmouth Gulf in Western Australia through the Northern Territory to Bustard Bay in Queensland.
• Globally, it ranges through the eastern Indian and western Pacific Oceans, from Taiwan and Indonesia down to northern Australia.
• It prefers shallow coastal waters with sandy or muddy bottoms, often around estuaries, bays, and seagrass meadows where prawns and small fish are abundant.
• Juveniles feed mainly on prawns, crabs, and small crustaceans before switching to a diet of small fish as adults.
• It’s an important predator in northern Australian prawn grounds, helping balance populations of small invertebrates and fishes.
• Adults can live up to around 6 years, growing rapidly in their first year — reaching maturity at only about 11 cm (4.3 in) and roughly 1 year of age.
• Spawning takes place year-round in tropical waters, with peak activity during spring in the Gulf of Carpentaria.
• Larvae drift with ocean currents before settling into shallow nursery areas like seagrass beds and lower estuaries.
• The Bluespotted Trevally is one of the most common medium predators in northern Australia’s coastal ecosystems.
• It’s frequently caught as bycatch in prawn trawl fisheries — often in large numbers but of little market value.
• Divers and snorkellers may see them cruising sandy channels or hovering above seagrass beds, their blue spots flashing in the sunlight.