Black Sea Trout
| Black Sea Trout | ||||||||||||
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Black Sea Trout ( Salmo labrax ) |
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| Scientific name | ||||||||||||
| Salmo labrax | ||||||||||||
| Pallas , 1814 |
The Black Sea salmon ( Salmo labrax ) is a species from the family of salmon fish (Salmonidae) in some tributaries of the Black Sea . Some authors regard it as Salmo trutta labrax as a subspecies of the trout ( Salmo trutta ).
features
Black Sea trout can be found in anadromous migratory form, colonizing lakes and remaining in small rivers for life (“sea trout”, “lake trout” and “brown trout”). It differs from the nominate form of the trout ( Salmo trutta ) by a higher number of gill spines (16 to 18). It reaches a length of up to 80 centimeters. The caudal fin is only slightly notched.
Way of life
The anadromous migratory forms colonize sea depths of up to 50 meters, to spawn they migrate down to flowing waters in the hill country. The local forms can be found in rivers and mountain streams with cold, clear water and stone or gravel floors. They spawn in fast flowing mountain streams. The spawning season is between October and January. Young animals remain in their natal river for two to four years before they migrate into the sea or reach sexual maturity in freshwater. The anadromous forms stay in the sea for two to four years before migrating to the rivers from April to May or just before the spawning season. The yellow or orange eggs, about 5 millimeters in size, hatch after six to eight weeks.
Various invertebrates serve as food, large migrating animals mainly eat fish and larger crustaceans.
Species delimitation and occurrence
Genetic studies show that Black Sea trout from the inflow into the northern Black Sea represent a different population compared to the trout ( Salmo trutta ), which occurs in the Atlantic , Mediterranean and Caspian Basins . The Salmo examined in the inflow area of the northern Black Sea can be assigned to a single species (the now extinct Salmo schiefermuelleri also occurred there). In addition, the Black Sea trout occurs in rivers in Turkey that flow into the southern coast of the Black Sea.
On the Balkan Peninsula , four species of Salmo , including Black Sea trout, have been identified in Serbian rivers that flow into the Lower Danube and acted as refuge during the Pleistocene glacial period . During the Pleistocene, Black Sea trout also extended to rivers in the Caucasus . During this time the Black Sea was separated from the Mediterranean Sea and significantly less salt, which should have influenced the way of life.
A Salmo population in the upper Volga near Lipkovska can possibly also be attributed to the Black Sea trout; it can be distinguished from the similar forms in the Balkans. The trout ( Salmo trutta ) occurs in the upper Danube and hybrids ( Salmo trutta × labrax ) may or even likely occur in the lower Danube, in the Dniester , Don and Dnepr .
threat
Overall, the species is classified as not threatened, the anadromous migratory forms have become very rare in Europe due to dam construction, but are still relatively common in Turkey .
swell
- Maurice Kottelat , Jörg Freyhof : Handbook of European Freshwater Fishes . Publications Kottelat, Cornol 2007, ISBN 978-2-8399-0298-4 .
Web links
Black Sea Trout on Fishbase.org (English)
Single receipts
- ↑ a b c d e f IUCN: Salmo labrax . 2011, accessed July 9, 2016.
- ↑ S. Marić, A. Snoj, Vera Nikolić, P. Simonović: Genetic differentiation of trout (Salmo spp.) Populations In Serbia ascertained using RFLP technique on PCR amplified control region of mitochondrial DNA. In: Acta Veterinaria , 56, No. 5-6, 2006, pp. 423-430.
- ↑ Hervé Bocherens, Gennady Baryshnikov, Wim Van Neer: Were bears or lions involved in salmon accumulation in the Middle Palaeolithic of the Caucasus? An isotopic investigation in Kudaro 3 cave. In: Quaternary International , 339, 2014, pp. 112-118.