Dicentrarchus labrax is widespread throughout the Mediterranean and Black Sea and is a targeted, highly commercial species. This species is also bred in aquaculture. It is difficult to determine population trends in the wild stock as aquaculture figures are combined with commercial landings statistics. However, based on what limited data is available and observation, it is estimated that there has been at least a 20-30% decline over 3 generation lengths, including 10 years in the past and at least 5 years in the future, especially given the likelihood of the loss of wild stocks due to hybridization. It is assessed as Near Threatened. More research is essential to accurately determine the population trend and threats to this species and to reassess this species in the future, as it may warrant a higher threat category.

This species is present in the eastern Atlantic from the British Isles and southern Norway to Senegal, including Madeira and the Canary Islands. It is present throughout the Mediterranean and Black seas. It has also migrated eastwards through the Suez Canal and has been found in the Gulf of Suez.

Mediterranean:
Dicentrarchus labrax is widespread in the Mediterranean, including the Alboran Sea (Molinari et al. 2003), the Iberian coasts (Macpherson et al. 2002, Clavero et al. 2006, Garcia-Rodriguez et al. 2006), the Gulf of Lions (Allegrucci et al. 1996, Ruitton et al. 2000, Jouvenel and Pollard 2001, Dumay et al. 2004, Claudet et al. 2006, Mouillot et al. 2007), the Ligurian Sea (Tunesi et al. 2002, Molinari 2005, Tunesi and Molinari 2005, Tunesi et al. 2005), the Tyrrhenian Sea (Allegrucci et al. 1997, La Mesa and Vacchi 1999, Brando et al. 2004), the Strait of Sicily and Ionian Sea (Allegrucci et al. 1997), the Adriatic Sea (Lipej et al. 2003, Malavasi et al. 2004, Bonaca and Lipej 2004, Dulcic and Glamuzina 2006), the Aegean Sea (Allegrucci et al. 1997, Koutrakis et al. 2003, Akin et al. 2005, Castilho and Ciftci 2005, Koutrakis et al. 2005, Yuksek et al. 2006) and the Egyptian coasts (Allegrucci et al. 1997). The species is also known from the Black Sea. It has also penetrated eastwards through the Suez Canal to the Gulf of Suez (M. Goren pers. comm. 2007).

This species is common throughout the Mediterranean and Black Sea. Food and Agriculture Organization (FAO) landings figures are available from 18 countries in the Mediterranean Sea. A sharp increase in landings appears to occur in the early 1990s, but aquaculture for this species began at that time and the figures represent a combination of aquaculture and commercial landing figures. The former influences the apparent rise in landings. It is not possible to tell from the FAO figures what the real trend in landings figures was over the last 10 to 15 years. However, based on what limited data are available and observation, it is estimated that there has been at least a 20-30% decline over the past 15 years (since the early 1990s), and with the introduction of aquaculture stocks, wild populations are expected to decrease even further in the future.

The following Greek catch figures include the aquaculture production:

Allegrucci et al. (1997) collected 60 specimens from the Gulf of Lions, 120 from the central Tyrrhenian Sea, 30 from the Ionian Sea, 30 from the Strait of Sicily, 30 from the Aegean Sea, and 30 form Egyptian coastal lagoon. Koutrakis and Tsiklis (2003) sampled 146 specimens, with length varying from 1.6 to 27.0 cm TL, using various fishing gears (beach-seine, fyke net, gill nets) in Porto Lagos (NW Aegean), a shallow coastal lagoon, between December 1988 and September 1990, and Strymon and Rihios estuaries (NW Aegean) in September 1997 and May 1999. Castilho and Ciftci (2005) collected 105 specimens from the eastern Mediterranean basin (the Beymelek lagoon Turkey in 1998, Patras, Greece, and the Ionain Sea) in 1996. Dulcic and Glamuzina (2006) collected 620 specimens, with length varying from 22.6 to 88.0 cm TL, in three eastern Adriatic estuarine systems, using various fishing gears (beach-seine, fyke-net, gill nets, fish traps) from October 1998 to December 2003.

This is an oceanodromous species with demersal behaviour, inhabiting coastal waters down to about 100 m depth but is more common in shallow waters (Lloris 2002). It occurs in the littoral zone on various substrata in estuaries, lagoons and occasionally rivers. The species enters coastal waters and river mouths in summer, but migrates offshore in colder weather and occurs in deep water during winter in the northern range. Young fish form schools, but adults appear to be less gregarious (Frimodt 1995). In the Ligurian Sea, Tunesi et al. (2005) observed juvenile D. labrax during April in shallow waters (from 1.5 to 2 m depth). Genetic studies by Castilho and Ciftci (2005) revealed that a Levantine basin sea bass population represents a further subdivision of this species in the eastern Mediterranean. It feeds chiefly on shrimps and molluscs, and also on fishes (Tortonese 1986). Spawning takes place, in groups, in the spring near the British Isles, and earlier in its southern range. Its eggs are pelagic (Muus and Nielsen 1999).

In the Mediterranean, first sexual maturity occurs generally between two and four years while in the Atlantic sexual maturity happens a little later (males between four and seven years and females between five and eight years). Spawning happens just once a year and it tends to be in winter, although in southern areas it can occur in spring. Eggs present 1-2 fat drops that fuse about 12 hours after laying. Embryo development lasts about three days at 13-14°C and larval development about 40 days at 19°C. Egg size is 1.1 to 1.5 mm, larval length at hatching is 3 mm.

This is a commercial species. It is used in commercial aquaculture and in public aquaria (Frimodt 1995). It is also highly sought by sport fishermen (Billard 1997).

In the Mediterranean Sea, hybridisation with escaped individuals from aquaculture is likely to have significant genetic pollution effects on the remaining wild stocks. Aquaculture of this species is concentrated in the Aegean and Adriatic Seas but is also spreading to other areas in the Mediterranean.

This is a commercial species. It is used in commercial aquaculture and in public aquaria, and it is marketed fresh or smoked (Frimodt 1995). It is also highly sought by sport fishermen (Billard 1997).

There are various fisheries management measures in place for this species in some countries. For example, in Turkey, there is a minimum legal length for catches of 18 cm, for sport fishing it is also limited to 5 kg per person per day.

Recommendations include separating the wild stock landing figures from the aquaculture production figures in the FAO statistics to enable population tends to be determined and conducting genetic studies to separate wild stock from aquaculture escapees and hybrids between the two. The conservation status of the wild population may then be able to be more accurately determined.