Transcript Barramundi
Barramundi Jacqueline Pitts Taxonomy Know as the sea bass in south-east Asia • Kingdom: Animalia – Phylum: Chordata • Class: Actinopterygii –Order: Perciformes »Family: Latidae • Genus: Lates • Species: L. Calcarifer Production Methods • Can only be grown in recirculation aquaculture tanks in NSW because of temperature requirements. The optimum temperature is 28°C, with acceptable growth rates between 26-30°C. The barramundi can be raised to market size (500mg) within 6-12months. • Aquaculture farms can be found in Australia, Malaysia, India, Indonesia, Israel, Thailand, United States, Poland. Production methods cont. Production Methods • http://www.daff.qld.gov.au/28_13323.htm Economics • The Australian barramundi industry has an annual production of more than 4000 tons • In Australia, there are two main products from farmed barramundi: 'plate size' and fillet product. 'Plate size' fish range from 350–500 g, although larger (banquet) fish may be up to 800 g. Fillet product fish are generally in the range of 2 to 3 kg. • There is relatively little import and export of barramundi – most are consumed locally. One exception is the culture of barramundi in recirculation production systems in the United States of America, with fingerlings exported by air from Australia. Economics cont. • Economic models of barramundi farming in Australia have estimated the break-even cost for a small (50 tonnes/yr) Australian farm to be AUD 9.25/kg (USD 6.90/kg), and the break-even cost for a 200 tonnes/yr farm at AUD 6.90 (USD 5.1). Larger farms (>1 000 tonnes/yr) are able to take advantage of economies of scale and their production costs are likely to be around AUD 6–7/kg (USD 4.50– 5.25/kg). • Can be found in Australia, Australia, Malaysia, India, Indonesia, Israel, Thailand, the United States and Poland Economics cont. • Barramundi are primarily breed for recreational purposes • And for also for food Life Cycle • The larvae metamorphose at 8-10 mm and are then called fry. Once the fry are over 20 mm (2-3 weeks of age) they are normally called fingerlings. Juveniles mature first at 3-4 years as males and change at 6-8 years to females. But in aquaculture conditions maturations occurs in about half that time. Spawn during full and new moons in the summer season (in nature), aquaculture is year round. Life cycle Reproduction in Captivity • The brood stock are held in floating cages, or fiberglass tanks. They can be maintained in fresh or salt water. But to prior to breeding season they must be placed in a salt water tank to enable the final gonadal maturation. Barramundi show no obvious signs of gender and must be examined to determine their gender and reproductive status. Pre-spawning the males then pair off with a female and rubs his dorsal fin against the area of the females genitals, he then erects his fins and “shivers”. Cont. • Within 34-38 hours after that, wild splashing starts at water’s surface. Spawn for 5 consecutive nights. Eggs are collected from spawning tanks using fine mesh nets (or is in cages the cage is lined with a fine mesh). The eggs undergo rapid development and hatching occurs 12-17 hours after fertilization. Feeds and feeding • The feed is typically compounded pellets, “trash” fish are used in poorer areas • The barramundi that are fed “trash” fish, are fed twice daily at 8-10 percent body weight for up to 100g. When the fish gets up too 600g the feed is decreased down to 3-5 percent body weight. Vitamin’s may be mixed into the “trash fish” at a rate of 2 percent. • Rice bran or broken rice can be added to increase the bulk of feed at minimal cost. • The ratio for food generally ranges from 4:1 to 8:1 Water chemistry and environmental requirements in culture • This includes the following: – Site must be above the 1/100 year flood heights. – Site must be at least 500m from a natural waterway. – Access to good quality water. – Adequate area for expansion and effluent disposal. – Close to markets and infrastructure. – Need solid removing filters and large biofilters to remove nitrogenous waste and nutrients – can also incorporate a number of other filtration units including UV and ozonation systems to disinfect water, protein skimmers to remove protein based wastes etc. After passing through the filters, the water is then recycled back to the tanks. Cont. • To comply with the NSW DPI Barramundi Farming Policy (also on this site), culture facilities in NSW must meet a number of additional design requirements including provision of a bund wall, effluent sterilization facilities, self draining floor, provision of sterilizing equipment ex: foot-baths • The barramundi can tolerate both fresh and salt water conditions. • DO levels must be between 4-9ppm, a low 3ppm can be tolerated but is not ideal and can’t be tolerated for very long • Ammonia levels shouldn’t exceed 1 mg/L • Temperatures should be maintained at 26-28°C Advantages Disadvantages Intensive In caged systems, excess fecal waste. Leading to water degradation Cost effective Diseases are hard to treat Lay millions of eggs $$$ to keep up It’s a hardy fish Needs to be heated Must have controlled light and temperature Water hogs References • http://www.dpi.nsw.gov.au/fisheries/aquaculture/p ublications/species-freshwater/barramundi--industry-profile • http://www.thefishsite.com/articles/569/culturedaquaculture-species-barramundi • http://www.daff.qld.gov.au/28_13323.htm • http://www.aquafarmer.com.au/Fish%20Farming% 20Hatchery%20Requirments.html