Beluga fish: how it looks and where it is found, its average weight and size, spawning features

The value of beluga fish cannot be overestimated. Gourmets around the world love dishes from her meat and caviar. They are considered delicacies of the highest category. This fish is one of the most expensive in the world. However, due to its large size and high cost, its population is now in danger of extinction, and fishing has been banned to save this species of fish. Its description and characteristics are truly amazing, because the beluga can rightfully be called a descendant of prehistoric marine life.

What a fish looks like

Beluga is the largest fish of the sturgeon family that lives in the fresh waters of Eurasia and North America. This fish is known for its excellent meat and is valued as a delicacy.

She has a long and thin body with silvery scales and several pairs of small antennae with which she finds food. The head is quite massive, and it has sharp teeth with which it captures prey. The fish can live several months without food, which allows them to survive in low water temperatures.

Head

The characteristics of the beluga head are unique and easily recognizable. Its dimensions seem enormous in combination with massiveness, and it is much wider than the body. At the top of the head is a short, pointed snout. The lateral and upper sides of the snout are soft, not covered with bony shields. The mouth is located under the snout, and when closed resembles a crescent shape. However, when the mouth is opened, it assumes a semilunar shape and is framed by thick, fleshy lips. The lower lip is cut into two parts.

The beluga doesn't have the back of its upper jaw, so it can't close its mouth completely. Instead, the fish use the powerful muscles of the tongue and throat to grip and grind food.

Under the mouth are four flat antennae with leaf-like appendages. The beluga lacks teeth in adulthood, but they are present in young fish. The eyes are small and located on the top of the head. The sight of this fish is poorly developed, so its orientation is mainly carried out with the help of a keen sense of smell and sensitive antennae near the mouth.

Despite the bulky and massive head, it is very suitable for life in cold waters. It carries a large layer of blubber that regulates its body temperature, while its short snout and padded areas make it easy to maneuver in high hydrodynamic conditions due to strong currents and cold waters.

Body

Beluga body is long, cylindrical, covered with smooth skin, without scales. It tapers towards the head and tail. The tail is narrow and cone-shaped, which helps the fish swim quickly and maneuverably.The lateral lines of the body, represented by rows of small holes, serve for sensitivity and orientation in the water.

Body color varies, but is usually silvery white or grey. On the sides and back, dark spots or stripes are often present, of various shapes and sizes. Color may vary depending on the age and habitat of the fish. For example, beluga whales that live in cold waters are dark in color. And those that live in warm waters look lighter.

Their body is covered with bony plates called bugs. There are from 11 to 14 of them in the dorsal row, from 41 to 52 in the lateral rows, and from 9 to 11 on the belly. Bone grains are located between the scutes. These plates form a tough armor that protects the fish from predators and other dangers.

However, unlike other fish, the beluga has practically no pronounced sexual dimorphism. This means that there are no noticeable external differences between males and females, except for some anatomical features.

How big it gets

This is one of the largest freshwater fish in the world. An adult beluga can reach impressive sizes, reaching a length of up to 5 meters and weighing up to 1.5 tons. The largest representatives live in Siberia and the Far East of Russia, where they reach a weight of up to 2 tons.

In the last century, cases of beluga fishing in the Caspian Sea with an impressive mass were recorded: in 1922, a fish was caught that weighed 1200 kg, and in 1924 - weighing 1000 kg. However, in our time, the mass of caught specimens has greatly decreased. In the period from 2013 to 2015, several representatives were caught in the Ural River, but their weight did not exceed 125-130 kg.

At the same time, the size of the fish varies depending on the region in which it lives. For example, in some rivers of North America, beluga whales are usually smaller, reaching a length of about 2-3 meters.

It is also worth mentioning that the size of the beluga depends on its age. Young belugas are usually about 60-80 cm long, and by the time they reach sexual maturity - at about 15-20 years old - their length can be from 1.5 to 2 meters, and their weight can be from 20 to 30 kilograms.

Habitat

The natural range of the beluga covers marine areas, including the Caspian, Azov and Black Seas. During spawning, these fish migrate to the mouths of the rivers flowing in these seas and rise along the rivers. Rivers known for finding large numbers of beluga where they can be caught include the Volga, Dnieper, Don, and Southern Bug. The Caspian Sea has the largest population of these fish, and they can be found in almost any river belonging to the sea basin.

They used to go upstream for many hundreds of kilometers, but due to the construction of hydroelectric power plants and reservoirs, their path to natural spawning grounds is closed.In the Black Sea, beluga whales are found off the coast of Crimea, off the coast of Turkey in the area of the Kyzylyrmak and Yeshylyrmak rivers, and off the Caucasian coast, at the mouth of the Rioni River.

Beluga is a type of fish that has an anadromous life cycle. Some of its species spend most of their lives in the sea, and then move to fresh water to spawn. Other species live only in rivers and lakes. They live at depths up to several hundred meters and are often found in areas of strong currents, close to the water surface or on the bottom.

The construction of dams and dams has a significant impact on fish populations and habitats. Beluga prefers to migrate along rivers over considerable distances for spawning and feeding, and the barriers created by dams and dams impede its movement. The water behind dams and dams also heats up and accumulates toxic substances, which negatively affects the beluga population.

Features of fish life

Beluga is a gigantic predatory fish that has a complex lifestyle. It is difficult for her to feed in the river, she hunts mainly in the sea, where a sufficient amount of food is available. Occasionally, she enters the mouths of rivers in search of food.

Belugas lead a solitary life if environmental conditions do not allow them to live in groups. During the spawning period, small groups are formed, which consist of 2-3 individuals, sometimes more. In a group, they not only look for food and defend their territories, but are also able to protect each other from predators. They lead a mobile lifestyle, always looking for food.

In the spring, individuals usually begin to actively move and eat in order to restore strength after hibernation. They become more mobile and often move in search of food. However, like most fish, the beluga prefers to be in places with warm water, especially on the coasts, where currents and winds create zones of increased temperature and abundant food.Also prefers places where rivers flow into the sea, as the water is warmer and richer in food.

Fish metabolism slows down in winter. This phenomenon is called thermoregulation and is typical of many species. This allows the fish to conserve energy and survive in conditions where there is less food and they cannot move quickly. Then the fish hibernates, its heart rate can drop to several beats per minute.

In the spring she goes to the rivers to spawn. Water quality is one of the key factors influencing the life cycle. If the water quality is low, then this can adversely affect her ability to spawn, to the point that the eggs in the female simply dissolve. This problem is especially acute in Russia, which significantly reduces the population of fish in natural waters.

Lifecycle

Beluga fish has a fairly long life cycle.She begins life as a fry, which hatches from eggs in the rivers, where the first stage of her life cycle takes place. In the first years of life, the beluga grows and develops in rivers, where it feeds on insects, fish and other small animals. During this time, she does not leave the river and is constantly in it.

When the beluga is about 5-7 years old, it starts migrating to the sea, where it will spend most of its life. The transition from the river to the sea is an important stage in its life cycle. In the sea, she becomes much larger and begins to eat fish and squid.

When the beluga is about 20-25 years old, it begins to migrate back to the rivers, where the second important stage of its life cycle takes place - spawning. She chooses rivers upstream, those where the conditions for spawning are the most suitable. At this stage of the beluga life cycle, the female lays her eggs on pebbles or sand at a depth of 2 to 5 meters.

After spawning, it can spend a few more years in the sea, feeding and growing to a large size, or it can immediately return to the rivers. Its general life cycle lasts from 30 to 60 years, depending on living conditions and habitat.

These fish spawn in spring and autumn. Depending on the season chosen for this process, 2 types of fish are distinguished: spring and winter representatives.

The first species goes to spawn in the spring, after the end of hibernation. This happens at different times depending on the region, usually in March, April or May. When the rivers begin to fill with meltwater, the water level rises and the fish reach the uppermost channels.

Winter beluga, in turn, spawns in autumn, in September-October. She is not often found in one place, tends to migrate long distances to find a suitable place to spawn.

This fish has a very good memory and remembers migration routes over a distance of 10 thousand kilometers. It is also capable of lingering in rivers for long periods to find food and suitable breeding conditions.

Diet

Beluga is a predator, and the main part of its diet is made up of smaller fish. Beluga fry in the first years of life feed on zooplankton, including crustaceans and mollusks, as well as small fish. They use their small tentacles to catch food in the water. As the fry grow, they begin to consume ever larger fish, including other small species of salmon, grayling and large insects that enter the waterways.

Besides, they sometimes hunt waterfowl and young Caspian seals. Among the fish that usually go to them as food, one can note carp, vobla, pike perch, crucian carp, herring. Also eats small sturgeon fish such as sterlet and sturgeon.

Although she is a predator, and not the smallest in the world, her diet is not limited to live food. Her diet also contains algae and other plant components, insects.

Spawning

Beluga doesn't grow fast, so it reaches puberty rather late.

Azov beluga females reach puberty by about 16-17 years of age, when their size reaches about 120-130 cm. Males are usually ready to spawn a year earlier. The Caspian variety "lags behind" in terms of performance by about 4 years.

Fish is a long-liver, on average it lives about 100 years. But age can vary depending on living conditions, feeding and other factors. Beluga females go to spawn once every 4-6 years, while males are ready to spawn every year. During spawning, females lay up to 30% of their mass of eggs, which are released into the water for fertilization by males.

The fertility of a female beluga depends on her weight. Usually, large females are able to produce more eggs than small individuals. The amount of caviar produced by one female may vary depending on her age and general he alth. Beluga females spawn once every few years, and the amount of eggs they produce may decrease with age.Some studies have shown that at the age of 20, a beluga produces an average of about 6 kg of caviar, while at the age of 50 years, the amount of caviar can be only about 2 kg.

When spawning time comes, the beluga, which spends most of its life at sea, heads upstream to spawning grounds.

She chooses places with fresh water, usually rivers or lakes, which allow her to return to her birthplace. The water should be deep and cold, with good oxygen levels and moderate flow. For the best laying of eggs and the survival of offspring, the purity and transparency of the water is important. At the same time, she swims several thousand kilometers.

Females spawn, and males swim up to fertilize. The eggs are all covered with a sticky substance, which allows them to stay in place and not be carried away even with a strong current.

About the offspring of beluga

Her caviar is large and has a peculiar shape. Each egg is a small bubble with a diameter of about 4 cm, inside which is the embryo. Typically, eggs are dark gray or black in color, due to the high content of melanin, the pigment that gives the dark color. Depending on the age of the female and other factors, the size and number of eggs varies greatly.

The hatching time of eggs depends on the temperature of the water in which they are located. It usually takes 5 to 12 days. At low temperatures (from 0 to 4 degrees Celsius), hatching can take up to 20 days. However, at high temperatures (7 to 10 degrees Celsius), hatching can occur as early as 4-5 days.

At high temperatures, the water contains more oxygen, which contributes to the rapid development and hatching of beluga larvae. However, if the water temperature is too high, it can cause the larvae to become deformed and weakened, reducing their chances of survival.

After hatching, the larvae quickly turn into fry and begin to search for food on their own. They live in shallow water and feed on plankton, various types of algae and other fry.

Most fry rush downstream to the sea. However, some individuals stay in the river for up to 5-6 years of age before heading to the sea.

When young sturgeons enter the sea, they are often found along shallow shores with low-salinity water. However, over time, they begin to move further and further into the s alty and deep parts of the sea.

Caviar features

Beluga caviar is one of the most expensive and luxurious delicacies in the world. It is gray-black in color and large in size, reaching a diameter of approximately 3.8 mm, and its weight fluctuates around 30 mg.

Among all types of beluga caviar is considered one of the most valuable due to its high protein content and low fat content. It is rich in important minerals such as iron, magnesium, phosphorus, zinc and calcium, which support bone and blood he alth.

In addition, beluga caviar contains vitamins A, B12 and D, which are essential for maintaining he althy skin, teeth and immunity. These vitamins also improve metabolism and maintain a he althy weight.

Beluga caviar is also high in essential fatty acids such as Omega-3 and Omega-6, which are essential for maintaining a he althy cardiovascular system. These fatty acids improve brain function, memory and concentration.

Beluga eggs are very much appreciated for their delicate taste, which is comparable to the aroma of a sea breeze and light corned beef. However, not every beluga caviar is so highly valued - in order to get a real delicacy, you need to follow many rules and requirements. The first rule is to use only caviar collected in a certain period of time. It is also necessary to take into account the temperature of the water in which the fish was before collecting caviar. The cooler the water, the more valuable the caviar will be. On average, the price per kilogram of beluga caviar ranges from several thousand to tens of thousands of dollars.

Natural Enemies

Adult sturgeons living in the seas practically do not know natural enemies because of their huge size, which does not allow other fish to attack them. However, for eggs, larvae, fry and young sturgeons, many small fish are dangerous: gudgeon, sturgeon, pike and others.

It's a paradox, but beluga are considered enemies of their own population, because sometimes they have cannibalism. This happens when larger individuals attack smaller ones or their own little ones. Cannibalism is observed both among adults and between fry that can eat "brothers" or eggs.

However, for adult beluga, the most serious enemy is man. Previously, before the ban on catching beluga during the spawning period, from 1.5 to 1.9 thousand tons of beluga were caught every year on the Volga River alone. Despite the ban on catching beluga, poachers still hunt these fish, which seriously reduces the number of beluga.

Population of the species

Over the past eight to ten decades, the beluga population has declined to appalling numbers. It began to decline catastrophically at the beginning of the 21st century, and this process continues today. Beluga Caspian, which has become an endangered species, is listed in the Red Book of Russia and the International Red Book. Over the past 80 years, the population has declined by more than 85%.

Decrease in the population of beluga fish in nature occurs for several reasons:

1. Overfishing. Beluga is a valuable commercial fish, and it is caught in large quantities. Overfishing can lead to the disappearance of fish from certain waters.
2. Negative environmental impact. Pollution of water resources, changes in their temperature regime, violation of the hydrological regime of watercourses, the presence of barriers on rivers and other factors negatively affect the living conditions of the beluga and lead to its extinction.
3. Construction of hydraulic structures. Culverts, such as hydroelectric power stations and dams, block the migration of beluga to spawning grounds, which reduces their numbers.
4. Climate change. Climate change in regions where the beluga lives may reduce habitat quality and make it harder to breed.

Is this fish bred

In 1952, Russian scientists obtained a hybrid of sterlet and beluga, called bester, from the words "beluga" and "sterlet" . Bester is grown in fish farms, and its hybrid nature gives it some advantages, such as a faster growth rate inherited from the beluga and an early puberty inherited from the sterlet.

The beluga breeding process can be described as follows:

1. Eggs are placed in an incubator where they remain until they hatch. The larvae are transferred to a special nursery and grown until they reach a weight of about 3 grams.
2. Then the fry are transferred to small ponds, where both natural and artificial feeds are used. Young fish eat not only minced fish, but also other supplements that promote he althy growth.
3. To ensure normal growth and development, the temperature and purity of the water in the ponds must be optimal, similar to natural conditions in the sea.
4. In winter, it is transferred to special wintering ponds, in which there is no bottom vegetation, but there is a great depth. Fish continue to feed, but in smaller quantities.
5. In the spring, fish are returned to feeding ponds where they continue to grow and gain weight.
6. When it reaches a weight of up to 2.5 kg, most fish are sent for sale to shops and catering establishments.

Application

Since ancient times, the beluga has been a valuable fish for fishing due to its huge size and high quality meat and caviar.Now its catch is prohibited for the conservation of the species. In fish farms, it is grown for commercial purposes. In natural habitats, it is protected by prohibiting fishing.

This is one of the most prestigious and expensive fish in world cuisine. S alted beluga is a real delicacy, which is prepared using the dry or wet s alt method. Smoked has a pronounced taste and aroma, ideal for sandwiches and snacks. Also used for preparing various salads and hot dishes.

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