Northeast Atlantic from Senegal to Norway, Mediterranean and Black Sea.

HABITS:

Open water, near rocks, shoals of "School Bass" enter estuaries during the summer and autumn. The very large fish may be solitary. Juveniles venture far up estuaries into brackish water to below 3% salinity in summer.

SPAWNING:

Adult bass adjust readily to captivity and may spawn naturally. Alternatively, they may be induced to spawn by the injection of human gonadotropin, carp, pituitary extract or luteinizing hormone-releasing hormone. Artificial stripping is unnecessary and egg viability is usually very good. The time of spawning may be shifted by photoperiod and temperature control. Each female bass spawns approximately 0.3 million eggs per kg. of body weight. The eggs are incubated in submerged net cones. The bass larvae hatch after 5-9 days, depending on water temperature, and are transferred to rearing tanks, which have a continuous flow of fresh seawater. The larvae are nourished by their yolksacs, but as the yolk becomes exhausted they are fed on microscopic live foods.

GROWTH:

The young bass are usually transferred to sea cages at a length of 3-4 cm, though they grow successfully in a wide range of salinity and temperature regimes and ongrowing may even be conducted in freshwater with natural zooplankton as food. Satisfactory growth is achieved at high salinities (30 to 37‰) and declines at lower salinity. When the water temperature is 22-25ºC, well-fed bass take less than a year to reach the minimum acceptable marketing size of 250 g.

USES:

Bass are subject to large fisheries in France, Spain, and Italy. In the last 25 years or so, the intensive cultivation of bass has developed rapidly in Europe, base mainly upon government-backed experimental systems.

CULTURE:

Over the centuries, extensive lagoon systems have been used in Europe for ongrowing with a reasonable degree of success, particularly around the Mediterranean, but also on the Atlantic coast of France. Intensive cultivation has quickly developed over the last 25 years. Today, economically viable commercial production has become a reality, and the early problems encountered with producing juvenile bass from eggs spawned in captivity have been largely overcome.

REFERENCES:

Bell, M.V.; McEvoy, L.A.; Navarro, J.C. 1996. Deficit of didocosahexaenoyl phospholipid in the eyes of larval sea bass fed an essential fatty acid deficient diet. Journal of Fish Biology 49:941-952.

Boge,-G.; Roche,-H. 1996. Cytotoxicity of phenolic compounds on Dicentrarchus labrax erythrocytes. Bull of Environmental Contamination and Toxicology 57:171-178.

Malvisi,-J.; della-Rocca,-G.; Anfossi,-P.; Giorgetti,-G. 1996. Tissue distribution and residue depletion of oxytetracycline in sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) after oral administration. Aquaculture 147:159-168.

Nathanailides, C.; Lopez Albors, O.; Abellan, E.; Vazquez, J.M.; Tyler, D.D.; Rowlerson, A.; Stickland, N.C. 1996. Muscle cellularity in relation to somatic growth in the European sea bass Dicentrarchus labrax (L.) Aquaculture Research 27:885-889.