Fish book son indd

Sturgeons – contemporaries of dinosaurs
117
The barbel sturgeon passes the same stages as all sturgeon species: 
embryonic, prolarva, larva, alevin, juvenile and adult.
A signifi cant amount of juveniles winters in the river. They mainly 
inhabit large, deep holes (10-18 m) with low fl ow rates. A portion of juveniles 
migrates to the sea the following year. Species that have wintered in the river 
for a second time stay in this river permanently, turning into a non-migratory 
type. Larvae stay on the Kura spawning grounds for several months and 
longer (up to 8 years). In the rivers barbel sturgeon juveniles are eaten by 
catfi sh and sander. The survival rate of barbel sturgeon juvenile is lower than 
that of other sturgeon species because it stays in the river for a longer time.
Males of the Kura barbel sturgeon reach maturity at the age of 9 years; 
females usually mature at the age of 14, and in rare case, at the age of 12-13.
The barbel sturgeon yields hybrid forms in nature with the beluga, 
the starred sturgeon (“starred sturgeon ship”), and the sturgeon. Through 
artifi cial fertilization, viable hybrids have been achieved in the Kura River: 
barbel sturgeon x sturgeon, barbel sturgeon x starred sturgeon, barbel 
sturgeon x beluga, and beluga x barbel sturgeon.
The Kura barbel sturgeon population is steadily declining. In 1980, 
between 66 and 112 specimens of barbel sturgeon entered the Kura River for 
spawning. In 1988-2000, they were found in single numbers.
The main causes for the catastrophic reduction of barbel sturgeon catches 
in the Kura River include:
runoff  control activities in rivers (1953) and loss of large spawning 
• 
grounds; non-recoverable water consumption, which causes the river’s low 
water levels;
off shore harvesting of “precious” fi sh, which continued until 1962;
• 
off shore seismic surveys;
• 
pollution of the sea, which has resulted in a loss of signifi cant areas of 
• 
spawning grounds for sturgeons, including barbel sturgeons (the area near 
Sumgait, the shallow water from Absheron to the Kura River mouth, etc.);
poaching.
• 
The species BARBEL STURGEON has been placed on the Red List of Azerbaij an
The species BARBEL STURGEON has been placed on the Red List of Russia
The species BARBEL STURGEON has been placed on the International Red 
List

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G.M.Palatnikov,  R.U.Qasimov
118
Starred sturgeon – Acipenser stellatus Pallas, 1771
Common names: Russian: sevruga; Azerbaij an:  uzun-burun, ag-balyg; 
Iranian: ozoon-boroon; English: starred (stellate) sturgeon
The starred sturgeon  is easily distinguished from all other sturgeon 
species by its unusually long nose, which almost has the form of a dirk and 
gives the fi sh a rather strange appearance. Its forehead is rather prominent. 
Its body is elongated, spindly, with fi ve longitudinal rows of bony scutes. 
Number od scutes: dorsal – 9-16; lateral – 26-43, which rise towards the 
tail end and extend to form the hamulus; and ventral – 9-14. The sides 
between rows of scutes are covered with light starry platelets. The top of 
the head is covered with bony shields. Snout is elongated and its length is 
more than half of the length of the head. Mouth is protractile and appears 
as a transverse slit; the lower lip is non-continuous. There are four barbels 
beneath the snout. The barbels have no fringe. The average number of gill 
rakers on the arch is 24.7-25.5. The dorsal fi n is taken far backwards and 
located above the anal fi n. Rhombic scales are found on the upper lobe of 
the caudal fi n.
The body has a sorrel color with a bluish-black hue; the sides and belly 
are white. However, the length and form of its snout considerably change; 
so female and juvenile snouts are always shorter, but starred sturgeons in 
the Sea of Azov, which generally reach their maximum growth here, are 
distinguished by their short snouts.
Generally, in terms of its length and weight, this fi sh ranks between the 
sterlet and the sturgeon. The starred sturgeon ranks signifi cantly below the 
sturgeon in size and never exceeds 5-5.5 m in length and 47 kg in weight. The 
average weight of this fi sh in the Caspian is 5.2-5.6 kg; in the Sea of Azov, 
where it is more abundant – 8 kg. With its similar weight, the starred sturgeon 
is always signifi cantly longer than similar sturgeon species, and the starred 
sturgeon with 24 kg weight can be up to 2 m in length.
In the Caspian Sea, the starred sturgeon is found in three populations: 
Volga, Ural and Kura.  Fish of Volga River origin prevail in the sea.

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Sturgeons – contemporaries of dinosaurs
119
This sturgeon species is spread throughout the Caspian Sea. For spawning, 
it enters the Volga, Ural, Terek, Sulak, Samur, Lenkoranka, Sefi d Rud, Kura, 
Aras and rivers of the southern coast as far as Gorgan.
Ac. stellatus is found in the Caspian Sea, the Black Sea, and the Sea of 
Azov, and very rarely in the Adriatic and Marmora Seas.
The starred sturgeon is a more pelagic species than sturgeon.  Moving in 
large depths in sea and river, it prefers to be kept in the water column. Within 
its geographic range, the starred sturgeon taps the food-rich ridges and the 
shelf zone of the sea, preferring the sea bott oms covered with silt or silt/sand, 
which are rich in diff erent species of minor crustaceans. It spawns on river 
beds, mainly on stony ridges.
In spring, it makes spawning (anadromous) migrations from the Middle 
and Southern Caspian to the Northern Caspian, from where mature fi sh enter 
the Volga, Ural and Dagestani shoreline rivers to spawn. Aft er spawning, 
they migrate downstream into the sea to feed. Feeding migrations are 
continuous movements of fi sh from one part of the sea to another in search of 
food. Pre-wintering migrations of starred sturgeon begin earlier than those 
of other sturgeons, namely – in August. The Ural starred sturgeon winters in 
the Ural and Mangyshlak deep trenches; the Volga starred sturgeon – along 
the Dagestani and Azerbaij ani shores. Immature species prefer the Turkmen 
shelf zone, where the water is warmer in winter.
Downstream migration of larval starred sturgeon to the Volga River occurs 
in June-August, predominantly within a 3-m layer of water. It feeds mainly 
on benthic organisms and fi sh. The starred sturgeon has a well-developed 
olfactory organ. When searching for food, the juvenile is constantly moving 
above the bott om and trying the substrate using tactile and taste receptors 
located on barbels and lips. The adult starred sturgeon and adolescent fi sh use 
the rostrum for digging into bott om sediments. When food item is detected, 
the fi sh makes a rapid seizing-sucking movement with its protractile mouth. 
Unlike other sturgeon species, the starred sturgeon’s capability to suck in 
food objects is strongly developed.
The larvae transition to active feeding on the 5
th
-9
th
 day aft er hatching 
when their bodies reach 18-19 mm in length. The main food items are 
Oligochaetae, Polychaetae, Crustacea, as well as larvae and pupae of 
Chironomidae. During the fi rst month in the sea, the juvenile feeds mainly 
on amphipods. In the Northern Caspian, crustaceans prevail in the food diet 
of the young starred sturgeon, whose body is up to 10 cm in length. In all 

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