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What representatives of sturgeons do you know. Sturgeon fish: varieties, habitat, catching and growing

In the article I will consider the habitat of sturgeon fish. I will list the features of the appearance, body structure. I will name popular valuable representatives families. I’ll tell you what they look like, where the beluga, sterlet, kaluga, sturgeon and others live.

The habitat of individuals of the sturgeon family is the northern hemisphere of the planet (water bodies of North America, Eurasia). The commercial underwater inhabitant is valued for taste qualities meat, caviar.

Some representatives are called anadromous: they migrate for spawning, wintering from the seas, oceans to freshwater rivers, then return back. In the family, semi-anadromous (moving to the mouths of rivers), freshwater species are also distinguished.

They hunt at the bottom of the reservoir (habitat depth from 2 to 100 m).

Omnivorous - they eat worms, molluscs, crustaceans, and insect larvae. The smallest representatives (sterlet) reach a meter size, weight 5 kg. Sturgeon giants (beluga) grow up to 6 m in length. Weight about one and a half tons.

Centenarians reach sexual maturity by 10-12 years. They spawn several times in their lives - usually after 2-4 years.

Appearance is similar to different breeds sturgeons. The body is elongated. The head is protected by strong bone shields.

Different types of sturgeon belong to the same family, but differ in the shape of the snout (xiphoid, elongated, short pointed-conical). Mouth toothless, slit-like or semilunar.

The main engine (caudal fin) is unequal, covered with scales in the shape of a rhombus.

What are the features

The oldest inhabitant of the planet Earth has a number of any features. We list them in the form of a list:

  • base of the skeleton cartilaginous notochord, not the spine;
  • the dorsal fin is located far from the head;
  • larvae develop for a long time, feeding on the substances contained in the yolk sac;
  • anterior ray of the pectoral fin thorn;
  • along the body (on the back, belly, sides) there are rows of large pointed outgrowths. Between them, the animal is covered with small bone tubercles, grains.

Consider the valuable populations of the family.

List of the most popular species and their names

Due to human intervention in the habitat of fish, the demand for tasty meat, expensive caviar, the population of the sturgeon family is sharply declining. Some representatives are listed in the Red Book. What else is known about famous predators- we will tell in the form of a list with names.

The size is the third largest after the beluga, kaluga. Genus anadromous, semi-anadromous, freshwater. Dimensions reach six meters in length, 800 kg (white sturgeon). Color - shades of grey.


The snout is sharp or blunt, spatulate or conical in shape.

Habitat:

  • Black Sea
  • Azov
  • Caspian Basin (90% of the sturgeon population)
  • coast of North America

They feed on shellfish, crabs, and shrimp. Valuable commercial fish is obtained due to meat, caviar, dorsal string (screeches), swim bladders.

It is successfully kept in volumetric aquariums equipped with powerful filtration, aeration - it loves clean water.

There are Black Sea, Azov, Caspian individuals.

The giant sturgeon differs in size - length up to 6 m, weight up to one and a half tons; life cycle duration is about 100 years. The Adriatic beluga disappeared in the 1970s.

The color is heterogeneous silver-brown, the belly is light. Snout without shields, short, pointed. The mouth is semicircular. The elongated body is covered with bugs, between them there are bone plates.


It feeds on herring, gobies. Predators were caught with baby seals in their stomachs. Commercial fish. Meat, caviar, skin, entrails are used. Swim bladders are used to make wine clarification glue.

Like many sturgeons, it interbreeds with other members of the family. Beluga is not kept in an aquarium, the hybrid will get used to a large unheated container.

The largest freshwater sturgeon - up to 5.5 m long, weighing about a ton. Life expectancy up to 55 years. The color is gray-green, heterogeneous. The belly is lighter than the sides and back.

The snout is shortened, pointed, in the form of a cone. The shape of the mouth is a large semicircle. The body is covered with bony plates. Lives in the Amur basin. Rarely found in the coastal zone of the Sea of ​​Okhotsk. It feeds on chum salmon, pink salmon, minnows.

Cases of cannibalism have been reported.

Meat, kaluga caviar are highly valued. Caught in nets. Not included in the Aquarium.


The smallest freshwater among sturgeons - the length reaches 1.2 m, weight 16 kg. Lives 25 - 30 years. There are individuals of two types - with a sharp or blunt snout. The color is modified in accordance with the habitat.

Most often silver-brown back, light yellow belly. They feed on mollusks, insect larvae, leeches, small fish.

Distributed in the basins of the Black, Azov, Caspian Seas. It is found in the rivers: Ob, Yenisei, Amur, Volga, Don and others.


Artificially bred in lakes, ponds. Commercial fish. The view is included in the International Red Book. Contained in aquariums with clean running water without plants. Grows slowly.

The stellate sturgeon is picky about food.

The representative with the longest flattened snout (about 60% of the head size). Antennae without fringes. The body is covered with rows of scutes, star-shaped plates.

Deep-sea inhabitant of the Black Sea, Caspian, Azov basins. They descend to a depth of up to 100 m. Length is not more than 2 m, weight is less than 80 kg.

Eats:

  • herring
  • gobies
  • crabs
  • shellfish
  • worms

Fishing is prohibited, but this does not stop poachers. Meat, caviar, fish entrails are valued. About 90% of stellate sturgeon is the result of industrial reproduction.

It is kept in a large aquarium with running water.

Most representatives of the ancient sturgeon family are on the verge of extinction. Disappearing large underwater inhabitants are hunted in huge quantities for the sake of satisfying human needs. Some species are bred artificially - in factories, in aquariums.

general characteristics

Sturgeon - pretty big fish(beluga reaches a length of 9 m). The body is elongated, almost serrated.

The sturgeon family belongs to the group of cartilaginous ganoids. On the body there are 5 longitudinal rows of bone shields - bug; muzzle elongated in length, almost spade-shaped or conical, with a small transverse toothless mouth; which lies on the underside of the head and can be retracted; on the underside of the muzzle, in front of the mouth, 4 antennae arranged in the form of a transverse row; vertical fins in front with one row of fulcra (see Ganoid); dorsal and anal fins close to the caudal; the gill membranes merge at the throat and are attached to the pharynx; gill rays absent; gill 4, there are also 2 accessory gills; the swim bladder is large, simple, communicating with the dorsal side of the esophagus.

Lifestyle

All sturgeons are either anadromous or freshwater; for throwing caviar, passers-by, as well as those living in lakes, enter the rivers. Sturgeons are extremely fertile and the number of testicles in large individuals is estimated at several million. In addition to the spring passage to the rivers for spawning, sturgeon fish sometimes enter the rivers in autumn for wintering. These fish keep mainly at the bottom, feed on various animal foods: fish, molluscs, worms, insects.

Commercial value

Black caviar in a glass

Sturgeons (namely, representatives of the genus Acipenser) are of great commercial importance, they were originally called red fish - for their special value. Their meat is highly valued, an even more valuable product is the famous black caviar; in addition, the swim bladder provides valuable glue, the dorsal string is eaten under the name vyazigi.

Currently, industrial sturgeon fishing is carried out only in the rivers of the Caspian Sea - the delta of the Volga and the Urals, as well as in Iran. Annually international organization CITES determines the catch quotas for each of the countries of the Caspian Sea. The size of the quota directly depends on the number of sturgeon fry released from special seaside fish hatcheries into the Caspian Sea.

Due to quota cuts and occasional total trade bans, all greater value receives commercial sturgeon breeding in fish farms around the world, there is a possibility that in the future it will become the main source of precious black caviar on the market.

Origin

In the fossil state, oster fish are known only from the Eocene. In terms of zoogeography, representatives of the subfamily Scaphirhynchinae are very interesting, which are found on the one hand in Central Asia, on the other in North America, which makes us see the remains of a previously widespread fauna in modern species of this genus.

Systematics

Sterlet

The encyclopedia of the beginning of the 20th century - ESBE - refers sturgeon to the order (or subclass) of the ganoid (Ganoidei), suborder (or order) Chondrostei. Modern taxonomy distinguishes sturgeons in the order of sturgeons from the class of ray-finned fish.

Kinds

In the older classification, only two genera were distinguished: sturgeon ( Acipenser) and scaphirhynchus ( Scaphirhynchus), containing only about 25 species found exclusively in the temperate zone of the northern hemisphere: in Europe, Asia and North America.

Modern systematics distinguishes 4 genera in two subfamilies - Acipenserinae and Scaphirhynchinae. Four species belong to the subfamily Scaphirhynchinae, the rest to Acipenserinae. These include 2 species of European sturgeon, sturgeon from Siberia and China, several species of sturgeon from the North. America, beluga, sterlet, stellate sturgeon, thorn. This includes mainly large fish.

Links

  • Sturgeons- article from the Great Soviet Encyclopedia

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See what "Sturgeon" is in other dictionaries:

    - (Acipenseridae), a family of fish of the sturgeon order (see sturgeon-like fish), a superorder of cartilaginous ganoids; includes four genera (beluga, sturgeon, shovelnose and pseudoshovelnose), 23 species. The length of sturgeons is up to 9 m, weight is up to 1.5 tons. They are characterized by ... ... encyclopedic Dictionary

    - (Acipenseridae) a family of fish from the order (according to other subclasses) ganoid (Ganoidei; see), suborder (according to other orders) Chondrostei. They are characterized by the following features: the body is elongated in length, almost valky, with 5 longitudinal rows of bone ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

    American Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) ... Wikipedia

    Fish (Acipeuseridae) is a family of fish from the order (according to other subclasses) ganoid (Ganoidei), suborder (according to other orders) Chondrostei. They are characterized by the following features: the body is elongated, almost valky, with 5 longitudinal rows of bone ... ... Encyclopedia of Brockhaus and Efron

    FISHES- are lower vertebrates that live in water. They belong to two classes of the subtype of vertebrates (Vertebrata) of the type of chordates (Chordata) Marsipobranchii and Pisces. The first belong to cyclostomes (Cyclosto mata) lampreys and hagfishes, to the second ... ... Big Medical Encyclopedia

    - (Acipenseridae), a family of fish neg. sturgeon. Anadromous, semi-anadromous and freshwater fish. There are five rows of bony scutes along the body. The anterior ray of the pectoral fins is in the form of a thick spine. There are 4 antennae in front of the mouth. 4 genera: beluga, sturgeon, shovelnose and ... Biological encyclopedic dictionary

    Fish, aquatic vertebrates with variable body temperature; breathe with gills, non-five-fingered limbs, usually in the form of fins. 2 classes: cyclostomes and R. proper. R. proper (Pisces) include 7 subclasses: acanthodes, arthrodirs and winged R. ... Great Soviet Encyclopedia

    Sturgeons- Sturgeon: 1 Beluga; 2 Siberian sturgeon; 3 spike; 4 sturgeon. Sturgeon, a family of valuable commercial fish. Length up to 9 m, weight up to 1.5 tons. 24 species, including spike, sterlet, stellate sturgeon, Russian and Siberian sturgeon, beluga. Anadromous and freshwater fish ... ...

    sturgeon- sturgeon. Sturgeons include sturgeon, beluga, spike, kaluga, stellate sturgeon and sterlet exclusively valuable fish, dishes and snacks from which are a characteristic feature of Russian cuisine. The body of sturgeons is covered with five rows of large bone scales, ... ... Brief Encyclopedia household

    Fishes- fresh waters of Russia: 1 chub 2 ruff; 3 asp; 4 crucian; 5 carp; 6 rudd; 7 bream; 8 tench; 9 burbot; 10 perch; 11 gudgeon; 12 roach. FISH, aquatic vertebrates. Known since the Devonian. They breathe with gills, limbs in the form of fins that serve for ... Illustrated Encyclopedic Dictionary


Sturgeon fish live in salty sea ​​waters spawning in fresh waters. Representatives of the species are found in various sizes. Small fish (sterlet and others) grow up to 100 centimeters and weigh up to 15 kilograms. The largest sturgeon is the beluga. The weight of the largest fish caught was 1580 kilograms, the length of the body with the head was 7.8 meters. The life expectancy of the species is 120 years. There are many large sturgeons in the world. They are of great value, because they bear black delicacy caviar.

Kaluga

Belongs to the sturgeon family. The body of the fish in length reaches 6 meters, weight - 1200 kg. Occurs in the Amur basin, near Hokkaido, Kamchatka, Sakhalin. Kaluga is the pride of Russia. Due to the rapid decline in numbers, it is listed in the Red Book. Environmental pollution, uncontrolled poaching are the main factors influencing the decline in the population.

The body of the kaluga is elongated, covered with bone plates in five rows with pointed spikes. The triangular head is covered with thick leather. The mouth is large, transverse. In the lower part are flattened antennae. The back and upper part of the fish's head are green, the belly is white. In size, Kaluga is second only to Beluga. This colorful representative Far East interesting to ichthyologists with unique habits and behavior:

  • Participate in spawning every five years;
  • Females are ready to breed at 17 years old, spawning up to 1.5 million eggs at a time;
  • The adult feeds by sucking in prey. The fish opens its toothless mouth and draws in, like a pump, the victim along with the water;
  • Kaluga is illegible in food. It feeds on bony, spiny fish covered with poisonous mucus.

Lives in the Azov and Caspian seas. It is found on the passage in the rivers Ural, Kama, in the Volga. Grows up to 100 kilograms, 2.5 meters long. The Russian sturgeon has a spindle-shaped body, a large pointed head, and a blunt muzzle. The tactile organ of the fish - skin processes (antennae) - are located at the end of the snout. With them, the sturgeon feels the bottom in search of food. The skeleton consists entirely of cartilage, like other representatives of sturgeons.


The body of the Russian sturgeon species is not covered with scales, but with bone plates. Natural armor protects the predator from damage. Members of the family lead a bottom life. Sexual maturity is reached at eight years. Freely interbreed with sterlet, stellate sturgeon, beluga. The female spawns 2-3 times in her life at intervals of 5 years. Russian sturgeon lives 50 years.

Since 1996, fish has been listed in the Red Book in Russia. It was decided to save the population due to many years of uncontrolled fishing. Black caviar remains an expensive delicacy. World exporters of the most valuable product are Turkmenistan, Russia, Azerbaijan, Kazakhstan, Iran.

A distinctive feature of the stellate sturgeon is an unusually long nose, similar in shape to a dagger. The forehead is convex, the antennae are flattened and elongated, do not reach the mouth, the lip is not developed from below. The weight and length of the body are different depending on the habitat. Fish can grow up to 2 meters with a weight of 80 kilograms. The maximum recorded age of a fish is 41 years.


The stellate sturgeon lives in the salty seas - Black, Caspian. For reproduction goes to the adjacent rivers. The body color of the fish is brown-black, the belly is white. Prefers to live and hunt at a depth of 100-300 meters, in the Caspian Sea - 3-15 meters. Azov stellate sturgeon is considered by fishermen to be a separate species. It feeds on small fish, mysids, amphipods. The Caspian inhabitant of the sturgeon family eats polychaete worms acclimatized in the region.


In the fishery, the stellate sturgeon takes the second place after the Russian sturgeon. Most of it is mined in the Urals. Fishing takes place in the spring with smooth nets. The number of fish of this species is much higher than the number of other sturgeons. This is due to the peculiarity of spawning. The stellate sturgeon does not rise high for laying eggs, it quickly goes to the sea.

The giant fish lives in European rivers and the seas. On the territory of Russia, it was seen twice - in the White Sea at the mouth of the Umba and in Kaliningrad region in the Baltic Sea. In length, the fish grows up to 6 meters with a weight of 180 kilograms. The species is adapted to life in salt and fresh water. The narrow and long body structure, enlarged caudal fin allow the underwater predator to move quickly at depth in search of food.


Deep-water areas are preferable for a representative of the sturgeon species. At the bottom, they feed on crustaceans and bottom molluscs. The life expectancy of a sturgeon is 100 years. Males become sexually mature at 11 years of age. Females are ready to bear offspring at 18 years old. Anadromous breeding fish move upstream once every two years and lay their eggs in areas with pebbles. After two weeks, fry appear, after 2 years they begin their journey to the sea. Along the way, they become prey to other fish. The development of sturgeons from caviar to adult fish occurs in stages:

  • In spring, the female attaches 2.5 million eggs to river stones;
  • After 10-14 days fry appear;
  • Larvae 9 mm in size have a rudimentary tail;
  • Weekly fry feed on yolk sac reserves;
  • After 6-8 months, the fry develop a mouth and antennae;
  • An adult fish stays in fresh water for two years, then goes to the open sea.

Thorn

Representatives of the species inhabit the Caspian and Aral Seas. Rarely seen in the Azov and Black Seas. Waiting out the winter cold migratory fish at the bottom of the Ural River. The main difference between spike fish and other sturgeons is the undivided structure of the lower lip. Protective bony plates cover the body of the fish. The color of the body is gray-green, the belly is light yellow. An adult fish grows up to 2 meters in length, weighing up to 20 kilograms.


The thorn is a sedentary fish. When moving, it muddies the water with its fins. Adapts to environment. It can stay in fresh waters for a long time, interbreed with other representatives of sturgeons. Lives in natural environment 20 years.

Puberty a spike occurs in fish by the age of 12. Fertility within 1 million eggs. It rises in the middle of spring up the river for spawning. The female attaches the eggs to the pebbles at a depth.

It belongs to the order of sturgeons, a species of ray-finned fish. Found in America, in the Gulf of Mexico. The only representative of sturgeon that feeds on phytoplankton and zooplankton at the same time. A characteristic feature of paddlefish is a constantly open mouth. Fish swim in such a state that they can take plankton and small fish with water into their mouths. Water is filtered through the gills, and the caught food enters the stomach.


The body of the fish does not have scales. The average length is two meters, weight - 85 kilograms. The third part of the body is occupied by a paddle-shaped head, on which a pair of antennae is located. The only fin on the back is shifted to the tail, located above the anal fin. The body color of the paddlefish is dark gray, the belly is silvery.


In Russia, this type of sturgeon has been bred since the 70s. Adult individuals were imported from America and placed in artificial freshwater reservoirs. Several hundred young paddlefish were released into the Krasnodar and Voronezh reservoirs. Fish in cultivation is unpretentious, grows quickly. Feels great in ponds with an area of ​​70 hectares at a water temperature of 25 degrees. Required condition- the presence of silt and vegetation at the bottom.

It lives in wide deep-water rivers flowing into the Laptev Sea, East Siberian, Kara Seas and Lake Baikal. The Siberian sturgeon is divided into subspecies. Lives settled or migrates for spawning. The body length of an adult fish is within 3 meters, weight - 30 kilograms. According to the shape of the muzzle, blunt-snouted and sharp-snouted sturgeons are distinguished. The mouth of both species is located under the head, adapted for eating benthic invertebrates.


The Siberian sturgeon is slowly developing and growing. Males become capable of producing offspring by the age of 10, females - at 12 years. Fish spawn once every five years, do not leave fresh water. They lay eggs in places with coarse-grained soil, fast current. Siberian sturgeons do not like sunlight, so they prefer to be at the depth of the reservoir.

A distinctive feature of the sterlet is an interrupted lower lip. The size of an adult animal is 1.5 meters with a weight of 16 kilograms. The sturgeon species lives in Siberia in the Yenisei basin. Sterlet has a commercial value.


Representatives of the species do not live alone, they move together through the reservoir. In winter, they lie on the bottom in one place. Hundreds of fish, closely pressed to each other, can wait out the cold in the deepening. In the photo, the sterlet in its natural habitat is represented by a pair or a group. The sociable nature of the fish encourages poachers to fish with nets.

Ichthyologists consider sturgeons to be among the most ancient on Earth. Representatives of these species swam in rivers when dinosaurs still roamed the earth. Sturgeon meat is a useful product. After cooking, less than 14% of inedible parts remain. A special delicacy is black caviar. The product is valued for nutritional properties, rare spawning of sturgeon representatives.

All species of sturgeon are valuable commercial fish, the population of which is rapidly declining due to the regulation of river flows, hydro construction, land reclamation, illegal fishing and others. negative factors associated with human activities. Attempts to increase their livestock in nature have so far yielded unsatisfactory results. For these reasons, all types of sturgeon are listed in the international, and some also in the Russian Red Book. In this regard, their breeding in artificial conditions (in fish factories, in artificial reservoirs etc.).

Sturgeon species of fish: photo and list

The sturgeon order is widely distributed in water basins North America, North Asia and Europe. There are both anadromous and semi-anadromous species, as well as freshwater ones. All of them are united by a long life cycle and excellent fertility, as well as a similar appearance, diet and lifestyle. Sturgeon species of fish, whose body structure resembles an elongated spindle, have 5 rows of bony bugs. Two are located on the sides and belly, and one is on the back. Between them are small plates and bone grains. The dorsal fin is located closer to the tail, and four antennae can be seen on the underside of the snout. The anterior ray of the pectoral fin resembles a thorn, from the transverse cuts of which one can determine the age of the individual.

On the territory of the former USSR, sturgeon species of fish live, the names and photos of which are presented below:

  • beluga;
  • Kaluga;
  • shovelnose;
  • sterlet;
  • stellate sturgeon;
  • Atlantic sturgeon;
  • Pacific (Sakhalin) sturgeon;
  • Russian sturgeon;
  • Persian (South Caspian) sturgeon;
  • Amur sturgeon;
  • Siberian sturgeon;
  • three false shovelnose (large, small and Fedchenko).

The sturgeon family is divided into two subfamilies: sturgeon-like (beluga, kaluga and all sturgeons) and shovelnose-like (American shovelnose and pseudoshovelnose). All representatives of sturgeons have a cartilaginous skeletal structure, in which there are no vertebrae, and the notochord is preserved until the end of life.

Sturgeon family: types of fish and their features

In addition to the main species, there is a wide variety of hybrid varieties, as they easily form hybrids by interbreeding in spawning grounds. Regardless of the species, fish spawn only in rivers with fast currents and oxygenated water, the bottom of which is strewn with pebbles, stones and sand. The sturgeon breeds several times during its life (but not every year) at a temperature of 15-20 ° C, so only the spring-summer period is suitable for this.

Juveniles of anadromous representatives (stellate sturgeon, beluga, Russian and Atlantic sturgeon, sturgeon) leave after leaving the eggs in the spaces of the mouth in the same summer together with adults, but some of the juveniles of sturgeon and Russian sturgeon may stay in the river for a year or more. The capacious yolk sac that the fry has contains nutrients, due to which they live for the first time. After its resorption, they begin to feed on their own: first they eat planktonic crustaceans (daphnia and cyclops), and then they switch to gammarids, mysids, chironomid larvae and oligochaetes.

Anadromous species of sturgeon are divided into winter and spring forms within each species, the degree of differentiation of which depends on the size of the river: in large water flows (for example, the Volga and the Urals), both forms are pronounced, in smaller ones, spring dominates, inferior in size to winter. The latter enters the rivers for spawning from the end of summer and in autumn, rising high, winters in pits, and spawns in the spring of the next year. The spring race rises into the rivers in early spring, but not high, and begins to multiply immediately, having reached the spawning ground.

Beluga

Most big representative sturgeons, which can be up to 5 meters long and weigh more than 1 ton, live the longest - up to 100 years. Archaeological finds of medieval beluga are known, the size of which exceeded 6 m. Fishermen of that time often died when such a giant came across their gear.

There are Black Sea and Azov subspecies, which, like all anadromous species, also have winter and spring forms, which prevail depending on which river the population spawns in. Azov individuals reach sexual maturity earlier - females at 12-14 years old, and males at 16-18. Other species are much later - 14-23 and 17-26 years, respectively. Beluga is the most prolific fish. The largest females lay eggs up to 7.7 million pieces

Kaluga

It belongs to the largest freshwater fish. Its length reaches 3.7 m, weight - 380 kg, and this representative of the fauna lives up to 55 years. Sexually mature kaluga becomes very late: males - at 17-18 years old, females - from 18 to 22 years old. The fish is extremely prolific: the number of eggs sometimes reaches 4.1 million pieces. By the way, there are different types of sturgeon caviar: pressed and granular. So in Kaluga, it reaches 4 mm in diameter. There are two forms of this giant: fast-growing firth (semi-anadromous form, spawning in the Amur) and river, smaller, forming local herds that do not move much in the river.

This is a pronounced predator: the estuary form feeds on salmonids (chum salmon, pink salmon) when they go to spawn in the Amur, but due to a decrease in their population, kaluga has been seen in cannibalism. The river subspecies eats small bottom fish such as minnows.

Sterlet

The smallest freshwater representative of sturgeons: reaches 1.2 m in length and up to 16 kg in weight. The sterlet has the largest number of lateral scutes (more than 50) and fringed antennae, which distinguishes it from other sturgeons. Another feature of this fish is the changeable shape of the snout, which is why two forms are distinguished - sharp-snouted and blunt-snouted. The latter grows faster, is more well-fed, and has greater fertility than the sharp-snouted relative. This difference is also inherent in other freshwater sturgeon - Amur and Siberian.

Males become capable of breeding at 4-5 years old, females - at 4-9. The number of eggs depends on the size of the females, as in other sturgeons, and reaches a maximum of 140 thousand pieces in the Volga, the largest sterlet.

Stellate sturgeon

Like all types of sturgeon, it has distinctive features: it is easy to identify by a very long snout (over 60% of the head) in the shape of a sword. This is an anadromous species dominated by the spring race, reaching 2.2 m in length and weighing 80 kg. The most heat-loving among migratory species, and therefore it spawns later than others, when the water temperature is more suitable (spring run at 10-14 ° C, autumn - 13-17 ° C). Males mature at 8-11 years of age, and females at 10 to 14 years. The population of Azov stellate sturgeon grows faster and matures earlier. The most prolific fish is the Ural. She lays up to 743,000 eggs.

Having finished spawning, immediately, without lingering in the river, it swims to the sea, where it eats Nereis and crustaceans. It occupies the first place in the sturgeon fishery. The main amount of stellate sturgeon is mined in the Urals.

Atlantic sturgeon

This is a large migratory sturgeon, reaching 3 m in length and weighing more than 200 kg. It has massive bugs on the body with a radially striated surface, and there is a powerful bone ray in the pectoral fin. Unfortunately, the once large population today numbers about 1 thousand individuals that live in the Black Sea basin.

Males reach reproductive age at 7-9 years, and females - from 8 to 14. Fertility is estimated at 5.7 million eggs. Without stopping after spawning, the fish quickly goes to the sea, where its main diet is anchovy. All types of sturgeon fish are of commercial value.

Russian sturgeon

Among the sturgeons, the Russian sturgeon occupies the main place in terms of numbers. Its distinctive features are a short obtuse snout and antennae without fringes, sitting closer to the edge. The fish grows up to 2.3 m, reaches a weight of 100 kg. It has complexly differentiated varieties of spring and winter forms that spawn in different periods. They have different sizes, growth rates, duration of stay in fresh water.

The Caspian representatives of the Russian sturgeon reach sexual maturity at 12-13 years old - males, and at 15-16 - females. Azov, on the other hand, mature earlier - at 8-11 and 11-15 years old, respectively. Like other sturgeon species, Russian is very prolific: one female can produce up to 880 thousand eggs. The main part of the fry goes to the sea, and some can stay in the river for 1-2 years. The favorite food of this species is shellfish. The fish also feeds on shrimp, crabs, nereis.

This family includes anadromous, semi-anadromous and freshwater fish inhabiting the water bodies of Europe, North Asia and North America.

Sturgeons are characterized by an elongated spindle-shaped tol, on which there are five rows of bony scutes: one dorsal, two lateral and two abdominal. Small bone grains and plates are scattered between rows of scutes. The snout is elongated, conical or spatulate. The lower mouth, in the form of a transverse slit, or lunate, extends in the form of a tube, bordered by fleshy lips, toothless; only in fry, weak teeth are formed, which subsequently disappear. On the underside of the snout, in front of the mouth, there are four barbels in a transverse row. The anterior (marginal) ray of the pectoral fin is well developed and turned into a spine. The age of the sturgeons is determined from the cross cuts of this beam. The dorsal fin is carried far back. The swim bladder is usually well developed (only in some sturgeons it is rudimentary, for example, in pseudoshovelnose).

Internal skeleton cartilaginous, the notochord persists throughout life, there are no vertebrae. Sturgeons are fish with a long life cycle. Beluga lives up to 100 years or more, Russian sturgeon - up to 50, stellate sturgeon - up to 30 years. The age limit of the sterlet, the least durable among sturgeon species, reaches 20–22 years.

Sturgeons (with the exception of sterlet and shovelnose) become sexually mature late. In different species and even in the same species in different basins, the age of maturation varies greatly, but on average males of anadromous sturgeon species reach sexual maturity not earlier than 10–12 years, females not earlier than 12–15 years. The most precocious are the Azov sturgeons, which enter the Don and Kuban for breeding.

The same fish does not breed every year and several times during its life. A large number of age groups of spawners participate in spawning. All sturgeons lay their eggs in rivers, in areas with pebble or pebble-sandy soil, in fast currents, under conditions of good oxygen supply. In the marine environment or in stagnant freshwater bodies, spawning does not occur. Anadromous species during the spawning run, as a rule, do not feed. Spawning grounds are of two types: in areas of rocky floodplains flooded by spring floods and in channel ridges located at considerable depths. Spawning occurs in spring and summer, usually at a water temperature of at least 15–20 °C. Caviar is sticky, after fertilization is firmly attached to stones and pebbles. The incubation period is short, only a few days (from two to ten). Sturgeon larvae hatching from eggs have a fairly large yolk sac and at first live off its nutrients. As the yolk sac dissolves, they pass to external (exogenous) nutrition. Sturgeon larvae first feed on planktonic crustaceans (daphnia, cyclops), then the fry begin to eat mysids, gammarids, oligochaetes and chironomid larvae.

Juveniles of anadromous sturgeon species (beluga, stellate sturgeon, spike, Russian sturgeon, Atlantic sturgeon, etc.) after hatching in the same summer, roll into the pre-estuarial spaces. Only in some of them, for example, in the Russian sturgeon and the spike, part of the juveniles can linger in the river for up to a year or more. Adult anadromous sturgeons also go to sea after spawning.

The main food of most sturgeon species is benthic and benthic invertebrates: crustaceans, worms, molluscs, chironomid larvae. By the nature of their diet, they are typical benthophages. Only the largest sturgeons - beluga and kaluga - are predators. The most important feeding areas for sturgeons, where their main stocks are concentrated, are the north of the Caspian Sea, the Sea of ​​Azov, and the northwestern part of the Black Sea. Semi-anadromous species of sturgeons (Siberian sturgeon, Amur sturgeon, Kaluga) feed in delta and pre-estuary spaces major rivers(Ob, Yenisei, Lena, Amur), and in the spring they climb up them for spawning.

Beluga (Huso huso) - above and Amu Darya shovelnose (Pseudoscaphirhynchus kaufmanni) - below"

Sturgeons are fast-growing fish that efficiently use the food resources of water bodies. It is interesting to note that the species living in the same basin differ quite strongly in their food spectrum and, as it were, complement each other. If we take, for example, the Caspian basin, then in the “bouquet” of sturgeon species living here, beluga is a typical predator, Russian sturgeon mainly feeds on mollusks, stellate sturgeon prefers worms and crustaceans, and freshwater sterlet eats small bottom invertebrates of the river (mainly chironomid larvae) . Thus, maximum utilization is achieved. forage base reservoir.

Anadromous sturgeon species are characterized by complex intraspecific differentiation, the presence of so-called "winter" and "spring" races. This phenomenon was first described for. some species of fish (sturgeon, salmon) by the outstanding Russian ichthyologist, academician L.S. Berg and revealed its biological meaning. Winter forms of sturgeons enter the rivers at the end of summer and autumn with immature sexual products, climb quite high along them, winter in the rivers in the pits and spawn in the spring of the next year. Spring birds go to the rivers in early spring with gonads ready for spawning, rise low along them and breed "on the move" in late spring - early summer of the same year. The degree of complexity of such differentiation depends primarily on the length and water content of the river: in large rivers (Volga, Ural), both forms are well represented; in relatively small ones, such as the Kura, spring forms predominate, which are usually smaller in size than winter ones.

The biological significance of winter and spring races in fish (including sturgeons) is apparently to ensure the fullest use of spawning grounds available in the river basin, including those located in its upper sections, to which fish cannot reach in one season.

Subsequently, the well-known Russian ichthyologist, Professor N.L. entry into rivers, the length of the migration route, etc.

The question of the hereditary fixedness of seasonal races and biological groups in sturgeon remains open to this day. Some researchers deny the possibility of interbreeding in nature of individuals of various intraspecific forms in sturgeons and consider them as genetically determined; others, on the contrary, do not recognize their rigid genetic fixation and believe that with known conditions transition and exchange of individuals between these groups is possible.

Different types of sturgeon in nature quite easily interbreed with each other, forming hybrid forms. There are known and described hybrids between thorn and stellate sturgeon, sterlet and Russian sturgeon, sterlet and stellate sturgeon, Kaluga and Amur sturgeon, Siberian sturgeon and sterlet, and other variants. IN Lately due to a sharp reduction in spawning areas in the rivers, caused by hydro construction and significant concentrations of spawners of different species on them, the number of hybrid forms in sturgeons is increasing.

In the sturgeon family, the sturgeon-like subfamily (Acipenserinae) is distinguished with the genera: beluga (Huso) and sturgeon (Acipenser) and the shovel-like subfamily (Scaphirhynchinae) with the genera: American shovelnose (Scaphirhynchus) and Central Asian pseudoshovelnose (Pseudoscaphirhynchus).

Shovelnose (subfamily Scaphirhynchinae) well differ from sturgeons proper (subfamily Acipenserinae) by a very wide flattened snout with sharp edges, as well as by the absence or weak development of the spire.

Beluga and Kaluga (genus Huso) reach the largest sizes among sturgeon fish, hallmarks which are a large mouth in the form of a semilunar slit and gill membranes fused together, forming a free fold.

They differ from each other in that in the dorsal row of bugs, the first (from the head) of the kaluga is the largest, and that of the beluga is the smallest.

Kaluga (Huso dauricus) inhabits the Amur basin from the estuary to its upper reaches. Occurs in Ussuri, Sungari, Shilka, Argun, Zeya, Onon. It does not go out to sea beyond the firth. There are two forms of kaluga: firth, semi-anadromous, fast-growing, coming to spawn in the Amur, and smaller, river, not making large movements along the river and forming several local herds.

One of the largest freshwater fish, reaching a length of 3.7 m and a mass of 380 kg; specimens over 5 m long have been caught in the past. The usual commercial weight of kaluga is 50–100 kg. The maximum recorded age of this fish is 55 years.

Sexually mature kaluga becomes very late: males at the age of 17–18 years, females - at 18–22 years. The length of the fish is about 220 cm. Kaluga breeds in summer, in June - July, in deep places with a fast current and pebble soil.

Its spawning grounds are scattered from Shilka to Tyr and below. The number of eggs laid is very large - from 665 thousand to 4.1 million. The eggs are large, about 4 mm in diameter.

Kaluga is a typical predator. In the Amur estuary, during the passage of Far Eastern salmon, it feeds on chum salmon and pink salmon; in connection with the decrease in the number of salmon, cases of cannibalism have now become more frequent. The food of the residential river form of kaluga is mainly small bottom fish: minnows, killer whales.

Thanks to a long-term ban on sturgeon fishing in the Soviet part of the Amur basin, kaluga stocks are now gradually recovering, and in 1976 they were restocked. started its strictly limited fishing in the estuary.

Beluga (Huso huso) common in the basins of the Caspian, Black and Azov seas; occasionally found in the Adriatic Sea, from where it enters the Po River. The Black Sea and Azov Beluga are often distinguished into subspecies (Huso huso ponticus and Huso huso maeoticus). Unlike the Kaluga, the Beluga leads a migratory lifestyle.

Beluga is one of the largest fish found in the fresh waters of the globe. In the last century and the beginning of this century, giant beluga were repeatedly caught - 4–5 m long, weighing 1 ton or more, 65–70 years old.

In 1922 near Astrakhan, a beluga weighing 1230 kg was caught. During archaeological excavations of medieval settlements located on the Volga, bone remains of beluga were found, exceeding 6 m. The approximate mass of such fish, apparently, reached 1.5 tons. It is not surprising that the struggle with such giants who fell on the tackle often ended tragically in the past for the catchers.

At present, the average commercial weight of the beluga entering the Volga is 70 kg for males and 125 kg for females; in the Urals, males weighing 40–60 kg and females weighing 60–100 kg predominate in catches.

For reproduction, the beluga climbed very high along the rivers, higher than other sturgeon species. Along the Volga, it reached Kalinin, met in many of its tributaries: Kama, Vyatka, Oka, Samara, Sura, etc. The main spawning grounds were located in the area from Kamenny Yar to the mouth of the Kama. A lot of beluga was caught in the Urals, where she met up to Orenburg. From the rivers of the western coast of the Caspian Sea, the beluga was very numerous in the Kura, along which even in late XIX in. went up to Tbilisi. The Azov beluga entered the Don in large numbers, and was caught here almost along its entire length. The main spawning rivers of the Black Sea beluga were the Danube, the Dnieper and the Dniester. Along the Dnieper, it rose early to Kyiv and entered its tributaries Styr, Pripyat, Sozh, Desna.

The course of the beluga in the rivers is rather extended. Like other anadromous sturgeon species, it has spring and winter forms. The peak of the course of the spring form usually occurs at the end of March - April; winter comes in September-November and winters in the river in the pits. Both forms breed in late spring and summer, from May to July. In the Volga beluga, the winter form prevails, in the Kura, on the contrary, the spring form, and in the Urals both are equally represented.

Beluga, like Kaluga, is a late maturing fish. The bulk of females going to spawn in the Volga reaches 17–26 years of age, males - 14–23 years. The central part of the spawning population of the Ural beluga is females aged 21–28 years and males 15–19 years old. Mature males of the Azov beluga occur at the age of 12–14 years, females at the age of 16–18 years.

Beluga breeds in the riverbed, usually on rocky ground. Its fertility is very high, depending on the size of the females, it ranges from 224 thousand to 7.7 million eggs; the average fecundity of the running Volga beluga is over 800 thousand eggs.

The regulation of the flow of most southern rivers caused severe damage to the natural reproduction of the beluga, as a result of which almost all of its spawning grounds were cut off. The number of this species is now entirely supported by artificial breeding in fish farms. From 1954 to 1977 about 200 million of its juveniles were released into the Caspian alone.

Beluga juveniles do not linger in the river and in the same summer roll into the sea. Beluga starts eating fish very early. The basis of its diet is made up of mass species: gobies, herring, sprat, anchovy, semi-anadromous cyprinids (vobla, ram). In the Caspian beluga, even seal pups were found in the stomachs. Recently, cases of eating other sturgeon by the beluga have become more frequent, which is apparently associated with a decrease in the number of its main food objects, primarily herring, gobies and roach. In 1952 on the Volga, under the guidance of Professor N.I. Nikolyukin, an intergeneric hybrid of beluga with sterlet, called bester, was bred under artificial conditions. This hybrid turned out to be prolific, characterized by rapid growth and easily matures in ponds, which opens up prospects for its use as an object of commercial sturgeon breeding, as well as for breeding new pond forms of sturgeons on its basis.

The sturgeon genus (Acipenser) is the richest in species among sturgeons. There are only 17 of them, of which the range of nine species also covers the water bodies of the Soviet Union. All sturgeons have a small mouth, in the form of a transverse slit, and the gill membranes are attached to the intergill space.

According to the number of chromosomes, sturgeons are divided into two groups: 120-chromosomal and 240-chromosomal species. The first group includes thorn, sterlet, stellate sturgeon, Atlantic sturgeon; to the second - Russian, Siberian, Amur, Adriatic sturgeons. The karyotypes of other species, mainly found outside the USSR, have not yet been studied.

A rather rare and rare species in this genus - thorn (Acipenser nudiventris). It is easily distinguished from other sturgeon by its unbroken lower lip. This is a large anadromous fish inhabiting the basins of the Caspian, Aral, Black and Azov seas. It is extremely rare in the Black and especially the Sea of ​​Azov. The spike can reach a length of more than 2 m and a mass of 50 kg. The age limit is 36 years.

In the Caspian Basin, the main river visited by the ship is currently the Ural; earlier, a lot of it entered the rivers Kuru and Sefidrud. In the Volga, the spike was always rare. It is interesting to note that the Volga fishermen call all sturgeon crosses spikes. For example, sturgeon spike is a hybrid between a spike and stellate sturgeon, sturgeon spike is a cross between sterlet and Russian sturgeon.

In the Aral Sea, the spike is represented mainly by the winter form, the entry of which into the Amu Darya and Syr Darya begins in April and continues until autumn (September–October). The length of the running spike in the Amu Darya reaches 143–175 cm and weighs 19–31 kg. In the river lies for the winter, spawning only in the next spring, from March to May. The thorn reproduces at water temperatures above 10 ° C in sections of the river with access to the surface of the bottom of rocks, less often on hard clay soil. The development of eggs at a water temperature of 19.5°C lasts 5 days. The main spawning grounds in the Amu Darya were located between Chardzhou and Turtkul, in the Syr Darya - in the Chinaz region. Spawned fish and fry slide into the sea in the same summer, but some of the juveniles, apparently, can linger in the river for more than a year. In the last 10–15 years, as a result of irrigation hydroconstruction in the Amu Darya and Syr Darya, the Aral spike has almost no spawning grounds left and it has become very rare fish.

In the Urals, the thorn, on the contrary, is represented only by the spring form, which enters the river during April. The average length of the running Ural spike is 130–155 cm and the weight is 12–19 kg. In recent years, about 3.5-5 thousand manufacturers have entered the Urals. Spawned individuals appear in the river delta in mid-May. Juveniles of the Ural thorn can stay in the river for up to 2–5 years, where a large number of them die from winter kills or predators. This ecological feature spike, apparently, and explains its small number in most reservoirs.

The spike first matures at the age of 12–14 years, males are 1–2 years earlier than females. Its fecundity in the Aral Sea basin is 52-575 thousand eggs, the Caspian spike (Kura) - 280-1290 thousand eggs. Mature eggs have a diameter of about 3mm. The main food of the ship in the Aral Sea and the Caspian Sea is fish (gobies, smelt), as well as mollusks.

The smallest species in the genus Acipenser is sterlet (Acipenser ruthenus). Her lower lip, unlike a spike, is interrupted in the middle, and it differs from other sturgeons a large number lateral scutes (usually more than 50) and fringed antennae.

The sterlet is very widespread, occurring in the rivers of the Black, Azov, Caspian and Baltic Seas. At the end of the XVIII - beginning of the XIX century. (perhaps even earlier) the sterlet penetrated from the Kama basin to the Northern Dvina through the canal system. It was found in the past and Onega and Ladoga lakes. It occurs in the large rivers of Siberia - the Ob, Irtysh and Yenisei, where it is represented by an independent subspecies - the Siberian sterlet (Acipenser ruthenus marsiglii). Further to the east (Pyasipa, Khatanga, Lena, Kolyma) is absent. The main sturgeon rivers are the Volga with tributaries, the Don, the Ob with the Irtysh. Sterlet was transplanted into many reservoirs: Pechora, Western Dvina, Mezen, Neman, Amur, but it did not take root everywhere.

Sterlet - typical freshwater fish, but in the Volga basin, a large semi-anadromous form is also found in small numbers (the average length of females is 74 cm and weight 2.8 kg), which feeds on the rich pastures of the Northern Caspian, and rises low along the river for spawning. This form of sterlet was even separated into an independent species (Acipeiiser primigenius). The existence of a large semi-anadromous fast-growing sterlet in the Volga (and, possibly, in our other southern rivers) is also confirmed by archaeological materials.

The usual commercial length of the sterlet is 40–60 cm, weight 500–2000 g. As an exception, it reaches a length of 120 cm and a mass of 16 kg. Such a specimen was caught in 1849. on the Volga, 100 km below Saratov. The sterlet is very variable in the shape of the snout, many researchers distinguish two forms in it: blunt and sharp-snouted. The blunt-snouted sterlet is characterized by faster growth, it is more well-fed and has a greater fecundity compared to the sharp-snouted one. Sometimes the blunt-nosed sterlet is considered as a winter form, and the sharp-nosed sterlet is considered as a spring form. Such morphological heterogeneity, expressed in differences in a special snout shape, is also characteristic of other sturgeon species closely related to fresh waters - Siberian and Amur sturgeons.

The biology of the sterlet has been well studied. She winters in the river in the pits, where she accumulates in large numbers; in spring, during high water, it rises upstream to spawning grounds. The sterlet breeds both in the riverbed and on rocky coastal ridges flooded with floods. The peak of spawning in the Middle Volga falls on May. The spawning grounds are usually dominated by males, each of which apparently participates in the insemination of the eggs of several females. In river conditions (Volga), sterlet males reached sexual maturity at 4–5 years of age, and at 7–9 years of age for females. Fertility with varies greatly, which is determined by the size of the females. The Volga sterlet lays from 4 to 140 thousand eggs, the Ob - from 6 to 45 thousand, the Irtysh - from 6 to 16 thousand. Caviar develops for about 4-5 days. The question of the periodicity of sterlet spawning has not been fully clarified. Some researchers believe that the sterlet spawns annually; others conclude that it breeds at intervals of 1–2 years.

After spawning, the sterlet is intensively fed. Its food consists of small benthic invertebrates: larvae of chironomids, midges, mayflies, caddisflies, mollusks. She also willingly eats eggs laid by other fish, including migratory sturgeons. During the summer of mayflies, the sterlet rises to the surface, turns upside down and collects insects that have fallen into the water with its mouth.

The regulation of the runoff had a very strong effect on the biology of the sterlet. In reservoirs (for example, in Kuibyshevskoye), it grows well, but does not mature well, it has a significant percentage of overweight dry fish. In addition, the conditions of natural reproduction are severely violated here (great depths, lack of flow and suitable soils for spawning). In the Kuibyshev reservoir, most females mature only at the age of 10–14 years. Spawning grounds are preserved here only in the uppermost areas, where there is a more or less pronounced current.

Therefore, it is so necessary to carry out on a large scale work on the artificial breeding of sterlet and stocking various water bodies with it. It should be remembered that it was the sterlet that was the object among sturgeons, the experiments on breeding of which laid the foundation for domestic sturgeon breeding, the centenary of which was celebrated in 1969.

This species is a traditional and old object of pond cultivation. In 1971 near Moscow, for the first time, it was possible to obtain offspring from sterlet spawners grown in cages installed in a reservoir, and later eggs and juveniles were obtained from fish kept in a thermal water facility at the state district power station, which opens up great prospects for the use of this most valuable species in commercial sturgeon breeding.

Stellate sturgeon (Acipenser stellatus) It stands out well among other sturgeons with its exceptionally long xiphoid snout, which is more than 60% of the head length. On this basis, as well as on a number of physiological and biochemical differences from other sturgeon species, some researchers propose to separate stellate sturgeon into an independent genus Helops. Her antennae are rather short, without fringes. The lower lip is interrupted in the middle. Reaches a length of 220 cm and a mass of 80 kg.

Sevruga is an anadromous fish common in the basins of the Caspian, Black and Azov Seas. It is found in small quantities in the Adriatic and Aegean seas. Forms local herds gravitating towards certain rivers. Spawning grounds for stellate sturgeon are usually located below the spawning grounds of other anadromous sturgeons. In the past, it went up the Volga to Rybinsk, entered the Oka and Kama; in the Urals met above Uralsk. A typical sturgeon river is the Kura, where earlier, before the construction of the Mingachevir hydroelectric power station, it reached the mouth of the Alazani. It also enters other rivers of the Caspian - Terek, Samur, Sulak, Astara, Sefidrud. In the Volga and at present, the stellate sturgeon breeds successfully below Volgograd; before the construction of the Volgograd hydroelectric power station, many fish spawned as far as Saratov. In the Urals, now the main stellate river, the main spawning grounds are located 300–400 km from the mouth, below the Inder Mountains. The Azov stellate sturgeon rises for spawning mainly to the Kuban, where it used to be found up to Nevinnomyssk, less to the Don, along which at the beginning of the 20th century. reached the mouth of the Khopra. In the Kuban, before the regulation of its runoff, the main spawning ground for stellate sturgeon was the section of the river between the Tbilisskaya station and the town of Kropotkin. From the Black Sea, the stellate sturgeon goes to the Dnieper (it used to reach Kyiv), the Dniester, the Southern Bug, Rioni, and the Danube.

It also forms seasonal races, but the spring form predominates in most rivers. The stellate sturgeon, unlike the Russian sturgeon, prefers faster rivers for spawning, and its massive entry into them occurs during the spring flood (April–May). Apparently, this explains the fact that in recent years, due to the deformation of the spring flood on the Volga, a significant part of the stellate sturgeon of Volga origin (up to 25–30%) goes to spawn in the Urals.

Among our anadromous sturgeons, stellate sturgeon is the most heat-loving fish, and therefore its spawning run into the rivers usually happens later and at more high temperatures water than in the beluga and Russian sturgeon (the maximum of the spring run in the Volga is at 10–14°C; the autumn run is at 13–17°C).

Sevruga is an early maturing species. The bulk of males of the Volga herd reaches sexual maturity at the age of 8–11 years, females at 10–14 years. The predominant age groups of the running Ural stellate sturgeon are 10–17 years old among males and 12–17 years old among females. Males of the Kura herd mature at the age of 11–13 years, females at the age of 14–17 years. The most early maturing is the Azov sturgeon: males become sexually mature at 5–8 years, females at 8–12 years. She is also the fastest growing.

The average weight of running males on the Volga in recent years is 6–7 kg, females - 11–12 kg; in the Urals, stellate sturgeon males going to spawn have average weight 6 kg, females - 10 kg.

The spawning period is quite extended: in the Volga - from May to August, in the Kura - from April to September, in the Kuban - from April to August, in the Don - from May to June. Spawning usually takes place at a water temperature of at least 18–19°C.

Fertility of stellate sturgeon in different rivers varies greatly: in the Volga - from 92 to 633 thousand eggs, in the Ural - from 19 to 743 thousand, in the Kura - from 35 to 360 thousand, in the Kuban - from 150 to 380 thousand.

After spawning, the stellate sturgeon does not linger in the river, but immediately rolls into the sea to the feeding grounds. Most of all, in recent years, it has been found off the western coast of the Caspian Sea, in the area from the Agrakhan Spit to the Absheron Peninsula. In spring, the stellate sturgeon begins to move to the north and gradually spreads over the entire water area of ​​the Northern Caspian.

The main food of the stellate sturgeon in the Caspian Sea is now acclimatized here in the late 30s, a lot of bristle worm Nereis, as well as crustaceans. Azov stellate sturgeon feeds on worms and small fish(gobies, hamsa).

In the sturgeon fishery, stellate sturgeon occupies the first place. Its main quantity is mined in the Urals.

Among the very large anadromous sturgeon is Atlantic sturgeon (Acipenser sturio). It is characterized by massive bugs, the surface of which is radially striated. In addition, there is a very strong bony ray in the pectoral fin. Reaches a length of 3 m and a mass of more than 200 kg.

The Atlantic sturgeon can serve as a sad example of how a once widespread and numerous species could not withstand human impact on it and in a short time almost disappeared from the fauna of our planet. Even in the middle of the XIX century. this sturgeon was commercial fish both off the coast of Europe and North America. He met in the basins of the Baltic, North, Mediterranean and Black Seas, off the coast of France, Spain, North Africa. Entered many rivers of Europe: Rhine, Elbe, Oder, Vistula, Loire, Garonne, Seine, etc. Along the American coast of the Atlantic, it was distributed from Florida to Hudson Bay. Its catches began to fall catastrophically at the turn of the 19th and 20th centuries; by the middle of our century, it had practically disappeared from the rivers of Western Europe and North America. Back in the 1930s Baltic Sea entered the Neva, climbed along it to Lake Ladoga, from where it entered the Volkhov, Svir, Syas for spawning. Perhaps in Lake Ladoga there was also a living form of this sturgeon. In 1953 A case of Atlantic sturgeon was caught in the White Sea.

At present, a small population of this sturgeon, apparently numbering no more than 1000 adult fish, has survived only on the Black Sea, in the basin of the Rioni River in the Caucasus. Single individuals are also found in the Danube and Po.

Sturgeon enters Rioni from late April to June. There is no autumn move here. The age of males going to spawn is at least 7-9 years, females - at least 8-14 years. The average size of running males is 137 cm, females 182 cm. The Rionskaya HPP did not affect its main spawning grounds, which are located 120–130 km from the mouth. The peak of spawning falls on the second half of May. The fertility of females ranges from 200 thousand to 5.7 million eggs. After spawning, the sturgeon quickly slides into the sea. In the Black Sea, it feeds mainly on anchovy.

Atlantic sturgeon is of exceptional value. It is characterized by a very high growth rate, significantly outperforming other sturgeon in this indicator. This species is included in the second edition of the Red Book of the USSR. For its artificial breeding, a fish factory was built in Rioni.

In many ways, it is close to the Atlantic sturgeon Pacific or Sakhalin sturgeon (Acipenser medirostris), but its bony ray in the pectoral fin is much less developed. In the Pacific Ocean, it is widely distributed, but very rare. Along the Asian coast it is found from the Amur estuary to Korea, in the rivers of Sakhalin and Primorye, off the coast of Hokkaido. Found in the Olyutorsky Bay of the Bering Sea. It is known along the American coast from San Francisco to the Columbia River.

Its biology has been studied extremely poorly. Reaches a length of more than 2 m, weight 60 kg. Leads a passing way of life. In our waters for spawning, it enters small rivers flowing into the Tatar Strait (Tumnin River), into the Tym River on Sakhalin, and also, possibly, into tributaries of the Amur Estuary. Presented as a winter form. It spawns in late autumn, winters in the river and spawns next year, in June-July. Spawning grounds are unknown. It feeds on benthic invertebrates and small fish. Also included in the Red Book of the USSR.

The central place in terms of numbers among sturgeons proper is occupied by Russian sturgeon (A. guldenstadti). It differs from other species in its short, blunt snout and the location of the antennae, which sit closer to the end of the snout than to the mouth. Antennae without fringes, lower lip interrupted. It reaches a length of 230 cm and a mass of 80–100 kg.

Its range almost coincides with the ranges of the beluga and stellate sturgeon. These are the basins of the Caspian, Black and Azov seas. Russian sturgeon also forms local herds, linked by breeding to individual rivers (Volga-Caspian, Ural-Caspian, Kura, Dnieper, Danube, etc.).

The sturgeon used to climb very high along the rivers, much higher than the stellate sturgeon. The main sturgeon river in the Caspian is the Volga, along which it was known almost to the upper reaches (Rzhev), as well as in the Oka, Klyazma, Sheksna, Vetluga, Kama, Vyatka. In the XVIII century. met, apparently, even in the Moscow River, as K. Rulye mentions: "... around 1740, even sturgeons came from the Oka to the Moscow River to the Kamenny Bridge, which no one remembers now ..." Main spawning grounds were located between Volgograd and Saratov. A lot of sturgeon enters the Urals, along which it ascended to the mouth of the Sakmara. It goes to spawn in other rivers of the Caspian Sea: Kura, Terek, Sulak, Samur. In the pool Sea of ​​Azov he was most numerous in the Don, along which he ascended to Zadonsk; much less than it in the Kuban. The most important spawning rivers in the Black Sea are the Dnieper, where it previously rose to Doro-gobuzh, the Danube, the Dniester, the Southern Bug, and the Rioni. As a result of flow regulation, most of the sturgeon spawning grounds were cut off.

In addition to the anadromous form, in the upper and middle sections of large rivers (Volga, Ural) there was also a resident form, which constantly lived in fresh water, was distinguished by its smaller size and slow growth.

The course of the sturgeon into the rivers is strongly extended; it forms winter and spring forms. The most difficult to differentiate is the sturgeon of the Volga-Caspian herd, in which early spring sturgeon (the maximum run is from March to May at a water temperature of 4–8 °C), late spring (run in May–June at a water temperature of 16–22°C), winter sturgeon in summer run (second half of May - July at a temperature of 18–24 °C) and winter sturgeon in autumn run (from August to October at a temperature of 24–8 °C). Sturgeon of different biological groups differ in size, length of migration, degree of maturity of the gonads, duration of stay in fresh water, and other indicators. Spawning of the Volga sturgeon of all biological groups (with the exception of late spring sturgeon) occurs during May at a water temperature of 9 to 16 °C.

The spawning population of the Ural sturgeon also has a complex structure, in which the mass flow of the spring form into the river is observed from the second half of April to mid-May, and the winter form - from late June to mid-August.

On the whole, as studies have shown, winter groups of sturgeon predominate in the Volga and Urals.

On the contrary, in the rivers of the Azov-Black Sea basin, sturgeon is mainly represented by the spring form. In the past, its mass flow in the Don was observed from April to May; a weak rise (winter form) was observed in September-November. Approximately the same picture was observed in the Dnieper. The Kuban sturgeon, apparently, is represented entirely by the spring form, which entered the river in April–May and immediately bred.

The average weight of running sturgeon on the Volga in 1977 was 21.2 kg (females) and 13.7 kg (males); in the Don before the construction of the Tsimlyansk dam (1952), sturgeon females had an average weight of 26–27 kg and males 11–13 kg; in the Urals, this figure for fish of both sexes in 1974 was equal to approximately 14.8 kg.

In the Northern Caspian, sturgeon males reach sexual maturity not earlier than 12–13 years and females 15–16 years. The Azov sturgeon becomes sexually mature somewhat earlier: males at the age of 8–11 years, females at 11–15 years. Mass maturation of males of the Danube sturgeon herd occurs at the age of 13, females - at 15 years.

The fecundity of the Russian sturgeon varies over a very wide range - from 60 to 880 thousand eggs, averaging about 250-300 thousand eggs. After hatching, sturgeon juveniles migrate to the sea in the same summer, but some may stay in the river for up to 1–2 years.

The favorite food of sturgeon in sea pastures is shellfish. He also eats shrimp, crabs, Nereis worm. Fish (gobies, anchovy, sprat) is his secondary food. In the total sturgeon catch in the 70s, it took the second place (after stellate sturgeon).

Recently, many researchers have identified as an independent species in the Caspian Sea Persian, or South Caspian, sturgeon (Acipenser persicus). It was first described at the end of the last century, but then considered as a subspecies of the Russian sturgeon (South Caspian) or as one of its intraspecific biological groups (Northern Caspian), the so-called late spring or summer spawning sturgeon. It differs quite sharply from the Russian sturgeon in its slightly lowered, massive, long snout, fewer scutes in all rows, and also in the gray-bluish color of the back. There are no less profound differences in a number of other morphological and physiological-biochemical parameters. The Persian sturgeon is on average much larger than the Russian sturgeon. In 1973 on the Volga, the weight of the female Persian sturgeon averaged 28 kg, while the weight of the female of the winter form of the Russian sturgeon was 19 kg; Persian sturgeon males are almost twice as large in weight as Russian sturgeon males (19 and 11 kg, respectively). For spawning, it enters the same rivers as the Russian sturgeon, but tends more towards the southern regions of the sea. The main spawning river for him was the Kura, but in recent years quite a lot of this sturgeon goes to the Volga and the Urals. The Persian sturgeon rises low and breeds in the same year when it enters the river. Spawning in summer, later than that of the Russian sturgeon, in July-August, at a water temperature of 20-22 °C. Fertility - from 84 to 837 thousand eggs (in Kura). The Persian sturgeon is of great interest as an object of fish farming.

In the rivers of Siberia, in addition to the sterlet, there is another representative of sturgeons - Siberian sturgeon (Acipenser baeri). But its range here is much wider. In addition to the Ob basin with the Irtysh and the Yenisei, it occurs further east, to the Kolyma, and also in Baikal. Sturgeon living in rivers Eastern Siberia(Lena, Olenyok, Yana, Indigirka, Kolyma), they are distinguished into a special subspecies - the Yakut sterletoid sturgeon, or hatys (Acipenser baeri hatys). The Siberian sturgeon is easily distinguished from the sterlet by a smaller number of lateral scutes (no more than 50), and from the Russian sturgeon, to which it is close, by fan-shaped gill rakers and a more pointed snout. However, the shape of its snout, like that of the sterlet, varies greatly, and along with sharp-snouted specimens, blunt-snouted ones also come across in the same place.

Its size in different pools is different. Sturgeons weighing 180–200 kg were found in the Ob and Baikal, up to 100 kg in the Yenisei, and up to 60 kg in the Lena. The average commercial weight of the Ob sturgeon is 15–16 kg, the Yenisei sturgeon is 4–6 kg, and the Lena sturgeon is 2–3 kg.

The Siberian sturgeon is a semi-anadromous fish. It feeds in the estuarine spaces of Siberian rivers, and for breeding it rises along them for many hundreds of kilometers: along the Ob, to the construction of the Novosibirsk hydroelectric power station, by 2500 km, along the Yenisei by 1500 km, along the Lena by 500-700 km. This migration lasts more than a year and is interrupted by wintering in the river in the pits (winter race). In addition to the migratory form, in most rivers it also has residential, sedentary groups. There are observations that mature, semi-anadromous individuals of sturgeon ascending to spawning grounds are colored in gray, smoky color, and residential sturgeon - in brownish-brown. The same differences in the coloration of these two forms were noted in the Amur sturgeon.

The Siberian sturgeon lives in very harsh conditions, grows more slowly than the Russian sturgeon, and matures late: males not earlier than 15–18 years old, females at 18–20 years old. The Lena sturgeon, which reaches sexual maturity earlier (males at 11–13 years old, females at 13–15 years old), is more early maturing, having very small, “sturgeon” dimensions (length about 70 cm and weight 1.5–2 kg ).

Several thousand years ago, the Siberian sturgeon penetrated Baikal (possibly from the Yenisei basin through the lower Angara) and formed here a unique lake-river form, which feeds in the shores of this lake (to depths of 150–200 m), and breeds in large tributaries ( Selenga, Barguzin, Upper Angara). The main spawning river is the Selenga, along which it rises to 1000 km.

In the rivers of Siberia, sturgeon breeds in summer, in June - July; Baikal - a little earlier, at the end of May - the first half of June. In different reservoirs, its fertility is different: in the Ob - from 174 to 420 thousand eggs, in the Yenisei - from 79 to 250 thousand, in the Lena - from 16 to 110 thousand.

Its food consists of a variety of benthic organisms: larvae of chironomids, caddisflies, mayflies, amphipods, gammarids, worms, mollusks, and less often fish. In winter, under the ice, it does not stop eating.

All Siberian sturgeons are of great interest for acclimatization and fish breeding. They are promising for stocking large reservoirs and lakes, as well as commercial sturgeon breeding, especially in warm waters.

The Siberian sturgeon is very unpretentious and has great growth potential. The Lena sturgeon grown in thermal water farms at the state district power station grows 7–9 times faster than in natural conditions. In 1981 at the Konakovskaya GRES, near Moscow, for the first time it was possible to get offspring from him: in the pools, females matured at the age of 8 years, males - at 4 years (i.e., much earlier than on the Lena).

Very close to Siberian Amur sturgeon (Acipenser schrencki), from which it differs in the shape of the gill rakers: they are not fan-shaped, but single-apex, smooth. It is likely that the Amur sturgeon is only a subspecies of the Siberian sturgeon. It is distributed in the Amur basin, from the estuary to Shilka and Argun. Forms semi-passage and residential forms; the latter is represented by a number of local herds. Length up to 2 m, weight up to 56 kg (in the past up to 160 kg). Males reach sexual maturity at 10–13 years of age, females at 11–14 years of age. Spawning in the channel of the Amur - in May - June. The main spawning grounds are above Nikolaevsk-on-Amur. Fertility - from 29 to 434 thousand eggs. By the nature of the diet, the Amur sturgeon is a typical benthophage.

In addition to water bodies of the USSR, a number of sturgeon species are also found in other regions of the northern hemisphere. The Adriatic sturgeon (Acipenser naccarii), which enters the Po River, lives in small numbers in the Adriatic Sea. To the rivers Atlantic coast North American sturgeon (Acipenser brevirostris) spawns. The very large white sturgeon (Acipenser transmontanus) is found along the American Pacific coast from Alaska to California. In North America, in the Great Lakes and the Mississippi and St. Lawrence basins, freshwater lake or brown sturgeon (Acipenser fulvescens) lives, which is very similar in biology to the Baikal sturgeon. Two species of Japanese anadromous sturgeon (Acipenser kikuchii and Acipenser multiscutatus) are found in the waters of the southern part of the Sea of ​​Japan. In China (Yangtze) there are two species of Chinese sturgeons (Acipenser sinensis and Acipenser dabrianus). All these species, with the exception of the American lake sturgeon, are very rare and have no commercial value.

In the subfamily of spade-nosed (Scaphirhynchinae), very peculiar fish are represented, well adapted to living in a fast stream of water carrying a large amount of suspension. The eyes of shovelnose are very small, often almost completely covered with skin, and vision does not play a big role in the life of these fish. On the other hand, the sense of touch is well developed, the organs of which are long antennae and, apparently, the entire lower surface of the snout. Large bone bugs, forming a kind of shell, protect well from mechanical damage and solid particles drawn by the flow. A flat spade-shaped snout serves to hold on to a fast current: a stream of water flowing over it presses the fish to the bottom.

shovels distributed in two regions of the globe: the genus American shovelnose (Scaphirhynchus) is found in the Mississippi basin, the genus pseudoshovelnose (Pseudoscaphirhynchus) is found in the Amu Darya and Syr Darya basins. The Central Asian shovelnose differs from the American shovelnose in a shorter caudal peduncle not completely covered with shields and a reduced swim bladder (in American shovelnose it is well developed).

There are two species in the American shovelnose genus: common shovelnose (Scaphirhynchus platorhynchus), having a length of up to 90 cm, and much more common white shovelnose (Scaphirhynchus albus) which can be up to 1m long.

Both species are typical river fish, and the white shovelnose lives in a faster current (lower Missouri). They breed in spring and summer, for spawning they enter tributaries with rocky soil. They feed mainly on aquatic insect larvae. The common shovelnose used to be an important object of fishing. Now the number of both species has declined sharply.

The Central Asian shovelnose is represented by three species, two of which - the large pseudoshovelnose (Pseudoscaphirhynchus kaufmanni) and the small pseudoshovelnose (Pseudoscaphirhynchus hermanni) - are found in the Amu Darya and one species, the Fedchenko pseudoshovelnose (Pseudoscaphirhynchus fedtschenkoi) - in the Syrdarya. The last two species have always been very rare. They became known to science quite recently, at the end of the last century. The Syrdarya shovelnose was found in 1871. the outstanding Russian geographer and traveler A.P. Fedchenko discovered the large Amu Darya shovelnose in 1874. the famous naturalist M.N. Bogdanov, and the small shovelnose in 1870. discovered in the Amu Darya by the zoogographer academician N.A. Severtsov.

Shovelnose inhabit the flat areas of these rivers, from the seaside to the foothills. IN salt water They do not go out of the Aral Sea. The size of the Central Asian shovelnose is small. The largest of them - the large Amu Darya - reaches a length of 58 cm and a mass of 760 g (as an exception, in the past there were specimens weighing up to 2 kg). Small shovelnose is much smaller, up to 27cm; the Syrdarya shovelnose similar to it has the same dimensions.

Shovelnose are typical inhabitants of the riverbed. They keep on sandy and pebbly shallows, in channels. In order to hold on to a fast current, in addition to a wide and flat snout, the small and Syrdarya shovelnose have a peculiar folded shape of the pectoral fins, which play the role of suckers. In the large Amu Darya shovelnose (and some of the Syrdarya specimens), the upper lobe of the caudal fin is elongated into a long thread, apparently performing the function of a balancer. At the end of the snout of a large shovelnose there are from 1 to 9 sharp spines, which probably play an important role in breeding in a fast current.

Shovelnose breeds on coarse-grained sandbanks and stony placers in the riverbed at a shallow depth (1.5–2 m). Spawning occurs in early spring, in March-April, at a water temperature of 14–16 °C. The female of the great shovelnose lays up to 15 thousand eggs, but usually no more than 2 thousand; the Syrdarya shovelnose spawns up to 1.5 thousand eggs; the fecundity of the lesser shovelnose is unknown. They reach sexual maturity at the age of 6–7 years; males usually mature a year earlier than females. In the great shovelnose, in addition to the usual form, a slow-growing dwarf is described, ripening at a length of 23–24 cm and a weight of only 39–40 g.

The favorite food of shovelnose is small benthic invertebrates (larvae of chironomids, caddisflies, mayflies), as well as fish roe. Greater shovelnose eats more big booty(juvenile barbel, sabrefish, loaches, sharp-eyed fish).

Indigenous people on the Amu Darya long time did not use the large shovelnose for food because of its long "tail", resembling a mouse or snake (hence the local name for this fish - mousetail or snaketail). The Ural Cossacks, resettled on the Amu Darya at the end of the last century, began to catch shovelnose. The meat of these fish tastes like sterlet.

At present, due to a sharp change in the water regime of the Amudarya and Syrdarya as a result of irrigation hydroconstruction, there are almost no places left suitable for their reproduction. Many juveniles of shovelnose perish under the scorching rays of the sun, falling through water intake facilities into irrigation systems. The number of these fish is now very small, and all three species of Central Asian shovelnose are included in the Red Book of the USSR.