sea bass aquaculture by: eric brown. what species are used? european seabass ( dicentrarchus labrax...

Sea Bass AquacultureBy: Eric Brown

What species are used?

European seabass (Dicentrarchus labrax)Sometimes marketed as Mediterranean Sea Bass.

Black Sea Bass (Centropristis striata) Spotted Sea Bass (Lateolabrax japonicus)

Reproduction

Seabass Life Cycle• 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•Protandrous except for European (dioecious)

Reproduction in Captivity

Feeding

Open WaterEggs feed on yolkJuveniles 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

Production methods used

Cages (new)Lagoon Systems

◦Intensive ◦Semi-intensive

Hatcheries ◦Broodstock◦Spawning

Lagoon SystemsSemi-Intensive

◦Fisherman collect fry from coastal waters May- June

◦Transport with oxygenated tanks to special ponds

Extensive◦February - May◦Barriers – reeds,nets, cement◦Nomally polycultured with seabream, mullets, and

eels

Hatcheries 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

waterSpawning

◦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

CagesMade of steel 4-10m²Nets suspended 6-8m

deepSome anchored on land

others in open watersFrequent net changes

(15-20 days)Weekly cleaning to

remove foul organismsDone by divers

Water Quality

pH – between 6-8Temperature – 20-

22 degrees Celsius Salinity – 27- 29

g/LDO – 7.5 ppmHigh rates of algae

Economic ImportanceOverfishing 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

Advantages Disadvantages

Very hardy fishCutting back on

OverfishingEasily marketedCould be inexpensive

if lagoon aquacultured

Long to matureVery competitive

marketLow filet yieldCarnivorousNo synthetic larval

feed