Because barramundi can reach a market size of 1. Farmed barramundi is a cost-effective, sustainable alternative to grouper, snapper, and halibut that is available year round with the leading aquaculture producers based in Taiwan, Vietnam, Malaysia, and Thailand. When uncooked, the flesh is pink and turns white when cooked. Barramundi has a sweet, buttery flavor and larger barramundi have a stronger taste profile than smaller fish.
The dense meat has large, firm flakes and the fish has a few large bones that are removed easily. The fish's mid-oil content helps to keep the flesh moist while cooking, lending itself to a myriad of preparations. Many times the fish is prepared pan seared with the edible skin left to crisp-up nicely. Barramundi is most commonly available as fresh and frozen in fillets, as well as portions. Buyer Beware: Product quality can vary considerably based on the production system, environmental conditions, and harvest method and fish raised in freshwater can be subject to off-flavor, so discerning buyers may wish to avoid pond-raised product.
A part of the sea perch family, barramundi can grow up to seven feet cm in length and weigh up to pounds 60kg. They are protandrous hermaphrodites, meaning they begin life as males and later turn into females, usually at three to five years old. They have a distinctly pointed head with a large jaw and rounded tail fin. Freshwater populations have a green-blue upper body with brown to black tail fins. Saltwater barramundi have a silver body with yellow tail fins.
Adults migrate from freshwater to coastal estuaries between October and April to spawn, which happens when tidal activities are strongest. Large females can produce up to 40 million eggs in one season; however, more than 90 percent of larvae and juveniles die within the first couple months.
Larvae hatch after 24 hours, relying on nutrients from the yolk sac until they are more developed, about two or three days later. Larvae remain in mangrove and tidal habitats until the springtime. Juveniles migrate into rivers if there is one nearby, where they take three to four years to develop into adults. Adults reach sexual maturity between three and five years old, where they migrate back to the saltwater to spawn.
Males turn into females at around six years old and three feet 80 cm in length, requiring saltwater for the sex change. Barramundi eat almost anything, including other barramundi, and can consume prey up to 60 percent its own length. Larvae eat plankton. Juveniles eat small fish, aquatic insects, and small crustaceans. Adults prey on fish and crustaceans. Predators of barramundi include large fish, birds, and reptiles such as saltwater crocodiles. Barramundi are native to the Indo-Pacific and are widely distributed throughout the region — ranging from Australia, Indonesia, Papua New Guinea, northward to the coast of China and Japan, and westward to India and various islands in the Indian Ocean.
They inhabit estuaries, lower reaches in rivers, and coastal waters. Barramundi prefer slow-moving rivers, creeks, swamps, and estuaries. However, they were forbidden because their tribe required Yalima to marry an elder so she could take care of him. Determined to be together, Boodi and Yalima ran away, knowing that to go against the Elders was punishable by death. They ran far and wide, but were relentlessly chased by the tribal elders. Eventually, they came to the edge of the land where the water began, and they knew that in order to survive, they would have to stand their ground.
With the angry tribe descending upon them, they gathered wood and made as many spears as they could. Boodi and Yalima are still there, in the shape of the Barramundi hiding amongst the mangroves. And the spines on the fin of the barramundi are said to be the spears thrown at them by the tribe. In the Wet Season, juvenile barramundi mm to mm long are forced back into rivers and they either remain or move up into freshwater billabongs.
There have been barramundi recorded at over 35 years of age, though a maximum age of 20 years is more normal. Most barramundi are born as males but at about eight years of age they turn into females. They can grow to cm long by the time they are eight years old. Barramundi eat just about anything that lives in or around water, including insects, spiders, crocodiles, prawns, fish and each other.
Research has shown that if there are high numbers of one-year-old barramundi from the previous year's spawning, they will eat the new recruits born the following year. During the build-up and Wet Season, water temperatures can be up to 10 degrees Celsius warmer than during the Dry Season. Read more about fishing seasons and weather forecasts. Overall survival for intensively-reared barramundi larvae from hatching to about 10 mm TL generally ranges from 15—50 percent.
More recently, compounded microdiets have been used to partly or totally replace brine shrimp in the intensive larval rearing of barramundi. Barramundi fingerlings are also produced using extensive pond-based rearing procedures. Pond areas used for the extensive larval rearing of barramundi range from 0. Larval rearing ponds are managed through the application of inorganic and organic fertilisers to produce a 'bloom' of suitable zooplankton concomitant with the introduction of the newly hatched barramundi larvae.
Continued pond management focuses on supporting adequate zooplankton populations for the developing larvae, and ensuring that water quality criteria are maintained. Barramundi are harvested from the ponds when they reach 25 mm TL or greater about three weeks after stocking , and are then transferred to nursery tanks. Survival of extensively reared barramundi averages about 20 per cent, but is highly variable, ranging from zero to 90 percent.
Nursery Barramundi juveniles 1. The fish are fed on minced trash fish 4—6 mm or on small pellets. Vitamin premix may be added to the minced fish at a rate of 2 percent.
This nursery phase lasts for 30 to 45 days; once the fingerlings have reached 5—10 cm TL they can be transferred to grow-out ponds. Cannibalism can be a major cause of mortalities during the nursery phase and during early grow-out because barramundi will cannibalise fish of up to 61—67 percent of their own length. Cannibalism may start during the later stages of larval rearing and is most pronounced in fish less than about mm TL; in larger fish, it is responsible for relatively few losses.
Cannibalism is reduced by grading the fish at regular intervals usually at least every seven—ten days to ensure that the fish in each cage are similar in size. Ongrowing techniques Most barramundi culture is undertaken in net cages. In Australia and the United States of America, a number of barramundi farms have been established using recirculation freshwater or brackishwater systems with a combination of physical and biological filtration.
These farms may be located in regions where barramundi could not otherwise be farmed because of consistently low temperatures southern Australia, north-eastern United States of America. The major advantage of such culture systems is that they can be sited near to markets in these areas, thus reducing transport costs for the finished product.
Barramundi are also farmed in earthen or lined ponds without cages; a technique known in Australia as 'free ranging'. Juvenile barramundi 20— g are cultured in brackishwater ponds at 0.
In Asia, barramundi may be polycultured in brackishwater ponds with tilapia Oreochromis spp. Feed supply Most barramundi are now fed on compounded pellets, although 'trash' fish is still used in areas where it is cheaper or more available than pelleted diets. Barramundi fed 'trash' fish are fed twice daily at 8—10 percent body weight for fish up to g, decreasing to 3—5 percent body weight for fish over g.
Vitamin premix may be added to the trash fish at a rate of 2 percent, or rice bran or broken rice may be added to increase the bulk of the feed at minimal cost.
Food conversion ratios FCRs for barramundi fed on trash fish are high, generally ranging from to Barramundi fed pellets are generally fed twice each day in the warmer months and once each day during winter. Larger farms may use automatic feeder systems, though smaller farms hand-feed.
Barramundi have achieved FCRs of 1. FCR varies seasonally, often increasing to over 2. Harvesting techniques For barramundi farmed in cages, harvesting is relatively straightforward, with the fish being concentrated into part of the cage usually by lifting the net material and removed using a dip net. Harvesting barramundi 'free-ranging' in ponds is more difficult, and requires seine-netting the pond or drain harvesting. Handling and processing After harvesting, the barramundi are placed in an ice slurry to kill them humanely and preserve flesh quality.
In Australia, most farms do not process the fish, but sell them 'gut in'. Some larger Australian farms have processing facilities to process fillet product from larger 2—3 kg fish. Fresh barramundi is generally transported packed in plastic bags inside styrofoam containers with ice. There is a limited market for live barramundi in Australia and in Southeast Asia.
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