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Sea Bass Aquaculture. By: Eric Brown. European seabass ( Dicentrarchus labrax ) Sometimes marketed as Mediterranean Sea Bass. Black Sea Bass ( Centropristis striata ) Spotted Sea Bass ( Lateolabrax japonicus ). What species are used?. Reproduction. Spawn in groups
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Sea Bass Aquaculture By: Eric Brown
European seabass (Dicentrarchuslabrax) Sometimes marketed as Mediterranean Sea Bass. • Black Sea Bass (Centropristisstriata) • Spotted Sea Bass (Lateolabraxjaponicus) What species are used?
Spawn in groups • External fertilization • Eggs pelagic • 2-4 year Sexual maturity • Longer in Atlantic • Ocean • Spawn once a year • Embryos develop in 3 days • Larval development occurs in about 40 days • Protandrousexcept for European (dioecious) Seabass Life Cycle
Open Water • Eggs feed on yolk • Juveniles feed on Zoobenthos (worms, crustaceans, polycheates • Adults – neckton (finfish & bony fish) • Aquaculture • Larva – only feed on small live food (Enriched Rotifers and artemia) • Adults – pellet feed (55% protein, 10% lipid) • FCR – 1.7:1 Feeding
Cages (new) • Lagoon Systems • Intensive • Semi-intensive • Hatcheries • Broodstock • Spawning Production methods used
Semi-Intensive • Fisherman collect fry from coastal waters May- June • Transport with oxygenated tanks to special ponds • Extensive • February - May • Barriers – reeds,nets, cement • Nomallypolycultured with seabream, mullets, and eels Lagoon Systems
Broodstock • Breeders of different ages are maintained here • Parent can be farm raised or wild • Females 5-8years, Males 2-4 years • Induce ovulation by hormone treatments • Fertilization in spawning tanks and incubation in open water • Spawning • Move selected breeders to spawning tanks • Male:Female – 2:1 • Only Females with oocytes in the late-vitellogenic stage (diameter larger than 650 micrometers) selected Hatcheries
Made of steel 4-10m² • Nets suspended 6-8m deep • Some anchored on land others in open waters • Frequent net changes (15-20 days) • Weekly cleaning to remove foul organisms • Done by divers Cages
pH – between 6-8 • Temperature – 20-22 degrees Celsius • Salinity – 27- 29 g/L • DO – 7.5 ppm • High rates of algae Water Quality
Overfishing is a large concern and aquaculture of this species has been deemed sustainable • Market price in U.S. $6.99 lb • Annual Production 60,000 tons • Turkey, Croatia, Spain, Italy, Greece Economic Importance
Advantages Disadvantages • Very hardy fish • Cutting back on Overfishing • Easily marketed • Could be inexpensive if lagoon aquacultured • Long to mature • Very competitive market • Low filet yield • Carnivorous • No synthetic larval feed