Barramundi: a Part of The Sea Perch Family

Barramundi, a part of the Sea Perch family, and the Aboriginal word for “large-scaled silver fish,” are prized for their fighting spirit, taste, and size. They can be found in the Coastal areas from Persian Gulf to China and Southern Japan, South Papua New Guinea and Northern Australia with many fisheries found in the Western Australian Kimberley area. Living in both salt and fresh water; in streams, rivers, lakes, billabongs, estuaries, and coastal waters. Barramundi inhabit areas where the water temperature ranges between 23 and 35 degrees Celsius.

Barramundis eat almost everything, including other Barramundis, and can consume prey up to 60% their own length. Juveniles eat small fish, aquatic insects and small crustaceans, such as prawns. Predators of the Barramundi include larger finfish, birds, and large reptiles, such as saltwater crocodiles.

Growing up to 200cm in length and 60kg, Barramundi dominate many finfish. Their appearance includes a pointed head, concave forehead, large jaw, and rounded tail fin. One of their two dorsal fins have 7 to 8 large strong spines, while the other includes 10 to 11 rays. Their colours depend on their living situations with the fresh water fish being green/blue on the upper body, dark brown to black tail and fins. While the saltwater fish have silver bodies and yellow fins. Barramundi utilise what is called a lateral line, which is a sensory organ that runs down both sides of the body. The lateral line enables fish to detect vibrations in the water and so be able to locate prey and avoid predators.

During wet season from October to April, the sexually mature Barramundi migrate from fresh to coastal waters to spawn. Mating usually happens when tidal activity is strongest. The large females can produce up to 40 million eggs during spawning season, although 90% of larvae and juveniles die in the first few weeks or months due to sickness, becoming prey or inhumane environments. After 24h since fertilization the Barramundi are ready to hatch. High tides and wet season floods wash eggs and larvae into mangroves and tidal habitats.

The larvae remain in the mangroves or tidal habitats until the end of the wet season. The juvenile fish then migrate into rivers and freshwater billabongs, where they develop into adults over the course of three or four years. When the fish become sexually mature (at three to five years of age) they migrate back to the saltwater to spawn and their life cycle begins again. Barramundi ages can be determined by counting growth rings on their scales. Barramundi are protandrous hermaphrodites, meaning they change sex from male to female. They become sexually mature as males at about three to four years of age. Males turn into females from about five or six years of age, and about 80 cm in length, but require saltwater for this sex change. Barramundi are thought to live to around 20 years of age.