Turbot fish photo and description
Turbot fish, which many have heard of, is not only a commercial object, but also an important object of cultivation in mariculture; the amount of turbot fish grown in captivity has long been many times greater than its catch in the seas. Therefore, it is necessary to take a closer look at what turbot fish is.
Content
- What is turbot fish?
- Description of turbot fish turbot fish photo
- What does turbot look like?
- What is the difference between turbot and flounder fish?
- Habitat of turbot
- Turbot's habitat
- Reproduction, development and growth of turbot fish
- Nutrition of turbot fish
- The importance of turbot fish in mariculture
What is turbot fish?
Let's start with something simple: what is turbot fish? Turbot, Atlantic flounder, turbot flounder or large diamondback is a ray-finned fish of the family Scophthalmidae, order Pleuronectiformes or flatfishes. The Latin name for the turbot fish is Scophthalmus maximus, with several synonyms found, including Psetta maximus.
Turbot fish is considered to be somewhat related to the Kalkan fish, which lives in the Black Sea.
Description of turbot fish turbot fish photo
What does turbot look like?
The description of the turbot fish is as follows: the body of the turbot has a diamond-shaped shape, strongly compressed from the sides, the height of the body is approximately 1.5 times less than the length of the body. The turbot has no scales. On the ocular side of the body and head there are small pointed tubercles, the diameter of which is less than the diameter of the eye. The upper profile of the head is concave in the area of the anterior edge of the upper eye of the turbot. Its snout is quite short, only slightly longer than the diameter of the eye.
The turbot's eyes are located on the left side of the body, they are widely spaced; the interorbital distance is approximately 2 times the diameter of the eye in adults; in juveniles it is no more than the diameter of the eye. The turbot's mouth is large, terminal, strongly sloping, the posterior edge of the upper jaw reaches the vertical line passing through the middle of the lower eye. The lower jaw protrudes slightly forward. The turbot's teeth are small, pointed, and arranged in several rows. The turbot has teeth on the vomer. There are 10-12 gill rakers on the lower half of the first gill arch. The dorsal fin of the turbot begins on the head, the beginning of the fin is on the vertical, which extends far in front of the edge of the eye. The dorsal fin has 57-80 soft, unbranched rays. The anterior rays are not longer than the other rays of the dorsal fin. The distal parts of the fin rays are not connected to each other by a membrane. The long anal fin has 43-58 soft rays. The dorsal and anal fins reach almost to the beginning of the caudal peduncle, but are not connected to the caudal fin. In the middle part of the dorsal and anal fins the rays are slightly longer than the other rays. The middle rays of the fins located on both sides of the body do not have scales. The pectoral fin of the turbot has 11-12 rays on the ocular side of the body; the rays located in the pectoral fin located on the blind side of the body are much shorter than the fin on the ocular side. The bases of the ventral fins are equal in length and elongated in shape. The fins of the turbot are arranged asymmetrically, the first ray of the right ventral fin is opposite the second or third ray of the left fin. The tail fin of the turbot has a rounded shape. The lateral line is well developed on both sides of the body and has a sharp bend above the pectoral fin.
The turbot has 30-31 vertebrae, of which 19-20 are located in the caudal spine.
In describing the turbot fish, an important point is the size and weight of the turbot. How big is a turbot fish? The maximum body length of a turbot reaches 100 cm, but usually the length of a turbot is 40-70 cm, the body weight of a turbot can reach up to 25 kg.
In the description of the turbot fish, it is interesting to note one feature - the turbot can change the color of its body, camouflaging itself from enemies against the background of the seabed.
What color is turbot fish? The color of the eye side of the turbot's body, as a rule, varies widely and coincides with the color of the seabed. In general, the color of turbot ranges from light gray or yellowish to dark gray or dark brown with a large number of dark and light round dots. The blind side of the turbot's body is usually whitish in color, sometimes with scattered, vague dark spots. The fins of the turbot are dark brown, mottled with light dots and spots.
What is the difference between turbot and flounder fish?
As has already been said, turbot fish and kalkan flounder are related species, however, the debate among scientists is still ongoing, some do not agree with this, but what is the difference between turbot and flounder?
The main differences between turbot fish and flounder are in size and how the tubercles are located on the body of the fish. It is believed that in turbot the tubercles are, as a rule, much smaller than the diameter of the eyes and are located only on the ocular side of the body, while in flounder the tubercles are larger than the diameter of the eye and are located on both sides of the body. However, it has been proven that in fish caught in the Sea of Azov, only the ocular side of the body is covered with bony tubercles. In the Baltic Sea you can catch specimens of turbot, both large and small tubercles that can be located on both sides of the body. The described differences in the number of rays in the dorsal and anal fins are considered unreliable.
Habitat of turbot
Where is turbot fish found? The turbot's habitat is very extensive and occupies the entire water area of the Atlantic coast of Europe, including the Mediterranean Sea in the south and the North and Baltic seas in the north. The boundaries of the turbot's range extend in the north to the Arctic Circle. The range of turbot in the south reaches the coast of North Africa to Morocco. The range of the turbot fish reaches Iceland to the west.
Habitat of turbot fish
Figure - Distribution area of turbot (Scophthalmus maximus) and galkan (Psetta maxima maeotica) in the North Atlantic and the Black Sea. Red indicates the main distribution of the population (large numbers), yellow indicates smaller clusters.
Turbot's habitat
Turbot fish is a bottom-dwelling fish that inhabits sandy and rocky bottoms. As a rule, turbot fish prefers to stay at depths from 2 to 80 meters. Fish under the age of one year concentrate near the shores, looking for desalinated areas of the sea. Adult turbot fish are able to withstand significant fluctuations in water salinity.
Reproduction, development and growth of turbot fish
When does a turbot fish reach sexual maturity? Male turbots reach sexual maturity at the age of 3 years, and females reach sexual maturity at the age of 4-5 years.
When does turbot spawn? Turbot spawning depends on the region, so in the Mediterranean Sea turbot spawning lasts from February to April; and in the North and Baltic Seas, spawning takes place from April to August, and turbot spawning in the more southern areas of the Atlantic takes place in May-July.
How does a turbot lay its eggs? Spawning in turbot is portioned, the female spawns eggs in separate portions every 2-4 days. Female turbots spawn at a depth of 10–80 m above pebbly soils.
How prolific is turbot? Turbot fish is very prolific. The fertility of turbot females varies in the range from 5 to 10 million eggs. Turbot caviar is pelagic, has a spherical shape with one fat drop, and reaches 0.9-1.2 mm in diameter. Despite the high fertility of turbot in nature, its population is largely in a depressed state, since a large number of eggs and juveniles die in nature.
The duration of embryonic development of turbot strongly depends on water temperature and reaches 7-9 days. At hatching, the length of turbot larvae ranges from 2.2 to 2.8 mm.
Turbot larvae have a symmetrical body and lead a planktonic lifestyle for several months. When the larvae reach a length of 25-27 mm, they complete metamorphosis, the eye moves to the left side of the body, and the juvenile turbot switches to a bottom lifestyle.
How fast does turbot fish grow? Turbot grows rather slowly. Females grow faster than males. At the age of 3 years, the body length of female turbots reaches 36 cm, and males 31.5 cm.
How long does turbot fish live? Turbot fish can live to be between 15 and 25 years old.
Nutrition of turbot fish
What does turbot fish eat? Juvenile turbot feed on invertebrates, mainly calanus, euphausids, larvae of balanus and gastropods. Adult turbots feed on fish - gerbils, European sprat, horse mackerel, whiting, Esmarck cod, juvenile haddock, sea bream and other fish. It can also feed on mollusks and polychaetes.
The importance of turbot fish in mariculture
Back in the 19th century, work began on the question of how to grow turbot in artificial conditions. But significant successes contributed to fish farmers only in the 20th century. More and more countries are commercially growing turbot, and since 2004, aquaculture production has exceeded the volume of turbot caught in natural conditions. Spain remains the largest producer of commercial turbot products. Large volumes of commercial production of turbot have been achieved in Portugal, France, Denmark, Germany, Iceland, Ireland, Italy, Norway, and Great Britain. Turbot is grown in mariculture farms in Chile and China.
In the future, there are all opportunities to breed and grow turbot in mariculture in Russia, Lithuania, Latvia, Estonia, Poland, Sweden, Finland in the Baltic Sea. Morocco, Algeria, Tunisia, Egypt, Turkey, Greece, Croatia, Albania, Montenegro, Bosnia and Herzegovina, Slovenia in the Mediterranean Sea.