Dicentrarchus labrax is a thick-set fish with large scales that can grow to a length of 100 cm. The flanks are silvery in colour and the fish has a black or blue back and a yellowish or white underside. Juveniles have black spots on the upper part of the body but these spots are rare on adults. Dicentrarchus labrax has two distinct dorsal fins, the first of which is spiny with 8 or 9 spines. The head is moderately pointed and the pre-operculum (gill cover) has a row of forward pointing denticles on the lower edge. Young bass tend to school together, however, the adults are more likely to be found in smaller numbers.

Adults manifest demersal behavior, inhabit coastal waters down to about 100m depth but more common in shallow waters (Ref. 54221). They are found in the littoral zone on various kinds of bottoms on estuaries, lagoons and occasionally rivers. They enter coastal waters and river mouths in summer, but migrate offshore in colder weather and occur in deep water during winter in the northern range. Young fish form school, but adults appear to be less gregarious (Ref. 9987). Feed chiefly on shrimps and mollusks, also on fishes (Ref. 5990). Juveniles feed on invertebrates, taking increasingly more fish with age. Adults piscivorous . (Ref. 59043). Spawn in batches (Ref. 51846). Spawning takes place in the spring near the British Isles, and earlier in its southern range. Eggs are pelagic (Ref. 35388). Marketed fresh or smoked (Ref. 9987). Highly sought by sport fishermen (Ref. 30578). The North Eastern Sea Fisheries Committee (NESFC) sea bass fishery of this species has been certified by the Marine Stewardship Council (http://www.msc.org/) as well-managed and sustainable (http://www.msc.org/html/content_1432.htm).

All European coasts. Absent from White, Barents, Baltic and Caspian Seas and from Northern Black Sea and Sea of Azov.

European sea bass are found from northern England to northern Africa and throughout the Mediterranean and Black Sea. (Wheeler 1975)

Biogeographic Regions: palearctic (Native ); ethiopian (Native )

Belgian Exclusive Economic Zone, Black Sea, British Isles, European waters (ERMS scope), Greek Exclusive Economic Zone, Irish Exclusive economic Zone, Israeli Exclusive Economic Zone [Mediterranean part], Oostende, Oosterschelde, Portugese Exclusive Economic Zone, Spanish Exclusive Economic Zone, United Kingdom Exclusive Economic Zone, Westerschelde, Wimereux, Zeeland, Zeeschelde

Eastern Atlantic: Norway to Morocco, the Canary Islands and Senegal. Also known from the Mediterranean and Black Sea. Absent from White, Barents, Baltic and Caspian Seas (Ref. 59043).

European sea bass are approximately 1 meter long. The body of a sea bass is covered by large, regular scales. Its color varies considerably, depending on the fish's origin, ranging from dark grey, blue or green on the back to a white or pale yellow belly. The flanks are silver-blue, sometimes pale gold or bronze. The head in young bass appears quite pointed, but it becomes blunter in older fish. Sea bass in their first year tend to be paler in appearance than older fish, and usually have dark spots on the back and upper sides. Normally these spots have disappeared by the time the fish is 1 year old, although some fish retain them well into adulthood. (Wheeler 1975, Pickett and Pawson 1994)

Range mass: 9 to 10 kg.

Dorsal spines (total): 8 - 10; Dorsal soft rays (total): 12 - 13; Analspines: 3; Analsoft rays: 10 - 12

Maximum size: 1000 mm SL

103 cm TL (male/unsexed; (Ref. 40637)); max. published weight: 12.0 kg (Ref. 1468); max. reported age: 15 years (Ref. 7253)

Posterior edge of opercle finely serrated, lower edge with strong forward- directed denticles. 2 flat opercular spines. Mouth moderately protractile. Young with some dark spots on upper part of body. Head with cycloid scales above. Vomerine teeth only anteriorly, in a crescentic band.

Habitat and Ecology

Systems

• Freshwater
• Marine

The European sea bass is typically an inshore species found in the surf zone, around outcrops of rocks, and in shallow coastal waters. Because they are found to be capable of surviving in estuaries in almost fresh water, it is thought that they could adapt to life in fresh water. In British waters they are migratory, approaching inshore in spring and summer, and moving into deeper water in late autumn. They spawn in inshore areas. (Wheeler 1975)

Aquatic Biomes: coastal

Depth range based on 511 specimens in 1 taxon.
Water temperature and chemistry ranges based on 138 samples.

Environmental ranges
  Depth range (m): -9 - 130
  Temperature range (°C): 7.200 - 12.243
  Nitrate (umol/L): 3.128 - 8.438
  Salinity (PPS): 34.186 - 35.570
  Oxygen (ml/l): 5.443 - 6.358
  Phosphate (umol/l): 0.247 - 0.635
  Silicate (umol/l): 1.843 - 4.696

Graphical representation

Depth range (m): -9 - 130

Temperature range (°C): 7.200 - 12.243

Nitrate (umol/L): 3.128 - 8.438

Salinity (PPS): 34.186 - 35.570

Oxygen (ml/l): 5.443 - 6.358

Phosphate (umol/l): 0.247 - 0.635

Silicate (umol/l): 1.843 - 4.696
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

 Dicentrarchus labrax is a demersal fish present in the littoral zone over most substrata usually only to 10 m in depth but have been caught at depths of 70 m. The bass is predominantly a marine fish but are found in brackish water and in summer months enter estuaries and can penetrate some way up rivers.

demersal; oceanodromous; freshwater; brackish; marine; depth range 10 - 100 m (Ref. 9987)

Oceanodromous. Migrating within oceans typically between spawning and different feeding areas, as tunas do. Migrations should be cyclical and predictable and cover more than 100 km.

The European sea bass is a predatory species feeding on mainly small pelagic fish such as sardines, sprats, and sand smelts. They also feed on sand-eels and other bottom-living species, crustaceans, and squids. Young fish tend to eat more invertebrates than do older fish. European sea bass are opportunistic predators and are known to attack prey species quite violently. Throughout their life, they develop a wide range of tactics to find and capture their prey. One specific tactic they use is to drive upwards toward the surface and attack from below at a steep angle. They tend to feed on whatever prey species are seasonally abundant in a particular location. (Wheeler 1975, Pickett and Pawson 1994)

Eurythermal. Gregarious when young. Voracious predator. High tolerance to salinity changes. Adults migrate to the estuaries in summer where they spawn in January-June. Young inhabit waters of 0.24-0.37% salinity where they feed mainly on zooplankton (Ref.. 11268). From 3.0 cm TL, diet changes to worms, crustaceans, fish larvae. Adults are strictly carnivorous surviving on small fish (Ref. 11243).

Dicentrarchus labrax preys on:
Sardina pilchardus
Clupeidae
Carcinus maenas
Crangon crangon
Nereis succinea

Based on studies in:
Portugal (Estuarine)

This list may not be complete but is based on published studies.

Isopoda infestation with Nerocila. Parasitic infestations (protozoa, worms, etc.)

Epitheliocystis. Bacterial diseases

Edwardsiellosis. Bacterial diseases

Spawn in groups. Eggs are pelagic. In the Mediterranean, first sexual maturity occurs generally between 2 and 4 years of age while in the Atlantic sexual maturity happens a little later (males between 4-7 years and females between 5-8 years). Spawning happens just once a year and it tends to be in winter, although in southern areas it can occur in spring. Eggs have 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 1.1-1.5 mm, larval length at hatching 3 mm.

Average lifespan

Status: captivity: 15 years.

Adult sea bass reproduce sexually by using external fertilization. The adults spawn from February to July. Temperature provides an important cue for the initiation and location of spawning because sea bass eggs are rarely found where the water is colder than 8.5-9.0 degrees Celsius or in water warmer than 15 degrees Celsius. During the spawning season, each mature female may produce between a quarter and half a million eggs per kilogram of her own body weight. Sea bass egg are planktonic and hatch between 4 and 9 days after fertilization, depending on sea temperature. During the following 2-3 months, the growing larvae drift from the open sea inshore towards the coast, and eventually into creeks, backwaters, and estuaries. These sheltered habitats are used by juvenile sea bass for the next 4-5 years, before they mature and adopt the migratory movements of adults. (Pickett and Pawson 1994)

Average age at sexual or reproductive maturity (male)

Sex: male: 730 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 1460 days.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 3
Species With Barcodes: 1

The European sea bass is not an endangered species, but there is a threat of over-exploitation of bass stocks. This is due to the fact that it is a very slow-growing species that can be over-exploited with only a little fishing effort. (Wheeler 1975)

IUCN Red List of Threatened Species: least concern

Population

Population Trend

Major Threats

Least Concern (LC)

Conservation Actions

The European sea bass is a renowned sporting fish, which is rated by British sea anglers as their best fighting fish. It is a species equally important to sport anglers and commercial fishermen. There is a strong international market for European sea bass and high prices are paid for them. (Pickett and Pawson 1994, Wheeler 1975)

fisheries: commercial; aquaculture: commercial; gamefish: yes