Fringefin Trevally

Interesting Info

• The Fringefin Trevally is a small coastal trevally where males grow long, trailing fin rays that look like streamers waving in the water.
• It can reach about 40 cm (16 in), but most individuals are much smaller, closer to ruler length or the size of a dinner plate.
• In Australia it is found across the tropical north from Port Hedland in Western Australia through the Gulf of Carpentaria and down to southern Queensland.
• Outside Australia it also lives in nearby waters of Papua New Guinea and eastern Indonesia, keeping it mostly within northern Australasia.
• Its upper body shines olive to bluish-green, while the lower body is silvery white, with a bold black spot on the gill cover and fins that glow yellow to orange.
• This fish prefers estuaries, river mouths, turbid coastal shallows, and seagrass beds where it can feed and hide.
• It usually lives in shallow water less than 30 m (100 ft) deep, right where sunlight reaches the bottom.
• Both juveniles and adults share similar habitats, often gathering in loose groups close to shore.
• Their diet includes small crabs and shrimps that they scoop up from the seabed.
• Researchers have noticed they appear more often in trawl catches at night and during neap tides, which suggests they may be more active then.
• The elongated fin streamers seen on males are thought to help them stand out during courtship displays.
• Their spawning has not been studied in detail, but they likely release eggs into open water during the warmer months like other trevallies.
• Although never very large, they are an important part of northern Australian estuary ecosystems, and their presence shows a healthy coastal environment.
• Its lifespan has not been formally studied, but similar small trevallies live around 5–7 years, reaching maturity quickly within just a year or two.