The Sea Mullet is the largest Australian mullet growing to a maximum size of 79 centimetres. They are a reasonably fast growing, short-lived fish, reaching sexual maturity after only three to four years. They are a solid-bodied fish and can be recognised by their small heads and large eyes, two separate triangular shaped dorsal fins, small mouth and large scales. The Sea Mullet differs from other mullet species by having a protective, transparent eyelid covering each eye. Mullet vary in colouration depending upon the habitat in which they live. Marine species are olive-green on the back with a silvery belly, and have darker grey longitudinal stripes along the body. A distinctive dark bluish-black spot occurs at the base of the pectoral fin. Juveniles inhabit estuaries, while adults form schools along the coast. They feed on organic detritus, micro-organisms, algae and the small worms and crustaceans that exist in the surface layer of mud on the seafloor in shallow water.
Sea mullet are marine fish occurring in coastal habitats, estuaries and occassionally enter into freshwater river systems. They are widespread overseas in warm temperate and tropical regions, and are found throughout coastal waters of Australia. Mature sea mullet undertake annual northward migrations to spawn in the offshore surface waters. This spawning behaviour appears to be triggered by strong westerly winds and decreasing water temperatures in late autumn. Once hatched the juveniles make their way back to estuaries.
Sea Mullet form a large and important part of commercial fisheries and on the east coast of Australia comprise about 4000 tonnes of the total catch.
Other common names include Hardgut mullet, river mullet, flathead mullet, mangrove mullet, grey mullet, bully mullet, striped mullet
Occurrence at the Busselton Jetty
The Sea Mullet are a rare visitor from the Underwater Observatory, but individuals have occasionally been seen in the open water zone, appearing to have been separated from the rest of the school.
Image by: O. Rynvis