Beluga mammal. The Belukha dolphin is a wingless northern angel. Social structure and reproduction

The beluga whale, or polar dolphin, is one of the beautiful views toothed whales.

Appearance

Beluga whales change color throughout their lives. Newborn individuals have dark blue skin, by the time of puberty the skin becomes bluish-gray, and in adults it is snow-white without any inclusions or spots.

Beluga whales are enough large mammals. The body length of males can reach 6 meters and weight up to 2 tons. Females are smaller in size. The head of these animals is devoid of a beak, but has a pronounced frontal part. The neck of beluga whales has a unique structure for aquatic mammals. The cervical vertebrae of these animals are not fused with each other, due to which beluga whales can turn their heads.

The fins located on the chest are small and oval. There is no fin on the back, which is why belugas are also called “wingless dolphins.”

The thickness of the skin of beluga whales can reach 15 mm, which protects them from injuries from ice. They are protected from the cold by a subcutaneous layer of fat, which can reach a thickness of 15 cm.

Lifestyle and diet

The lion's share of beluga whales' diet consists of sturgeon fish, such as cod, herring, capelin. Beluga whales do not disdain mollusks and crustaceans. In pursuit of prey, these animals can travel tens of kilometers.

Beluga whales make seasonal migrations. In the warm season, they live off the coast, in small bays and river mouths. The choice of such habitats is determined by the abundance of food in summer time year, water temperature and the presence of pebbles in shallow water, against which beluga whales rub in order to remove “dead” skin. Beluga whales remember their flying locations and come to the same place every year.

In winter, beluga whales stay close to the ice edge. But sometimes they can swim into places of deep glaciation. Beluga whales are not afraid of ice, as they can break through ice cover several centimeters thick. There are also tragic cases when ice holes are covered with a very thick layer of ice and beluga whales cannot escape from this captivity.

The enemy of beluga whales on the shore is the polar bear, and in the water killer whales pose a danger.

Beluga whales prefer to travel in groups. Females with cubs and males always live separately, uniting only while hunting for large schools of fish. In such cases, the group may number hundreds of individuals.

Beluga whales constantly communicate with each other, making various sounds. Scientists have identified about 50 sound signals.

Like dolphins, beluga whales can emit ultrasonic signals that are formed in the air sacs of the tissues of the head and focused in a fat pad located on the forehead, called an acoustic lens. These signals are reflected from various objects and are picked up by the lower jaw and then transmitted to the middle ear. These signals allow belugas to receive information about their environment.

Reproduction

Mating of individuals and the birth of young occur near the coasts. The mating season occurs in spring and summer. Fights for the female often occur among males. The gestation period is 14 months. More often, one cub is born, the body length of which does not exceed 160 cm. Feeding of the offspring can occur from one to 2 years.

Females are able to bear offspring from 4-7 years of age, and males reach maturity by 7-9 years. The lifespan of beluga whales is 40 years.

Spreading

Beluga whales can be found in the northern seas, such as the Sea of ​​Okhotsk, the White Sea, and the Berengov Sea.

Population protection

Beluga whales are listed in the Red Book with the status "vulnerable". The main threat is not the hunting of beluga whales, but the pollution of their habitats with waste and the industrial development of the Arctic shelf.

Belukha – rare view toothed whale and one of the largest mammals on Earth. It can be easily distinguished by its unique coloring and body shape. Born blue or light gray, the beluga whale turns white at puberty. The magnificent head looks very similar to a dolphin with a characteristic smile and an intelligent, inquisitive look. The absence of a dorsal fin and a movable head give the impression of a swaddled person.

Origin of the species and description

The name Delphinapterus leucas comes from the Greek "delphis" - dolphin. "Apterus" literally translates to without a wing, which immediately indicates the beluga whale's lack of a noticeable dorsal fin. The species name "leucas" comes from the Greek "leucos" - white.

According to the phylum, Delphinapterus leucas belongs to the highest chordates. This oceanic mammal of the cetacean order belongs to the narwhal family. The only representative of the Belukha genus is (Delphinapterus de Lacépède, 1804).

Video: Belukha

The first descriptions of the beluga whale were created towards the end of the 18th century. Researcher Peter Pallas, while in Russia, heard about an unusual animal and recorded eyewitness accounts. Subsequently, during a visit to the Ob Bay, the naturalist was lucky to personally see and describe in detail white whale in 1776. The animal was included and classified in animal reference books in 1804.

Belukha is considered a real find for biologists of all countries and is still considered an incompletely studied animal. Disputes about the unity of the white whale species arose in the mid-twentieth century. Some biologists tried to divide the toothed whale into species, while others insisted on uniform standardization.

Hypotheses about the origin of the species and debates about the structure of the animal genus raged until beginning of the XXI centuries. Today, agreement has been reached on the issue of species membership. The white whale is identified as the only one and unique view beluga whale

Interesting fact: Scientists believe that the first whales descended from terrestrial mammals that returned to the water 55-60 million years ago. The first representatives of the narwhal family appeared later - 9-10 million years ago in the northeastern part of the Pacific Ocean.

Appearance and features

The beluga whale is called the ocean dolphin. A beautiful small head with a characteristic raised appendage, an elongated nose and a “smiling” mouth unmistakably identifies the whale as a relative of dolphins. The beluga whale's movable head distinguishes it from other relatives in the order. This feature was preserved in the species thanks to the vertebrae, which were not fused, like in other representatives of cetaceans.

Thanks to this feature, the toothed whale has outwardly pronounced shoulders, a wide chest and a body tapering towards the tail. The skin is smooth, glossy, elastic. The body length of an adult whale reaches 6 meters. The beluga whale has disproportionately small front fins compared to its body. Their length is 1% of the total body length - 60 cm, their width is 30 cm. Tiny flippers are compensated by the width of the tail. Its span is a meter, and sometimes more.

Anatomical and physiological characteristics whales are adapted to life in the Arctic. The weight of an adult male can vary from 1600 to 2000 kilograms. A large percentage of the weight is subcutaneous fat. In white whales it can reach half of their body weight, while in other whales it is only 20%.

Animals have well-developed hearing. The unique properties of echolocation allow the beluga whale to find breathing holes under the ice cover of the ocean. The white whale's graceful jaw contains 30 to 40 teeth. They have a wedge-shaped shape, which occurs due to the friction of teeth against each other. This is due to the whale's oblique bite. Slightly extended jaws and forward-sloping teeth allow the beluga whale to bite off its prey.

These whales are slow swimmers. The speed ranges from 3 to 9 km per hour. However, a beluga whale can develop maximum speed 22 km per hour and hold it for 15 minutes. They have good maneuverability. They can move both forward and backward.

They enter shallow water when the water barely covers the body. Usually beluga whales do not dive very deep, about 20 meters. However, they are capable of diving to extreme depths. Under experimental conditions, a trained beluga whale easily made several dives of 400 meters. Another whale dived to 647 meters. A typical dive lasts less than 10 minutes, but they can stay underwater for more than 15 minutes.

Where does the beluga whale live?

The toothed whale lives in northern waters:

• Ocean;
• Seas;
• Bays;
• Fjords.

Enters the shallow waters of the Arctic seas, continuously heated sunlight. There are cases when beluga whales appear at river mouths. This happens in the summer. Whales feed, communicate and give birth. The water temperature at this time ranges from 8 to 10 degrees Celsius.

Beluga whales are found in the arctic and subarctic oceans of Canada, Greenland, Norway, Russia and Alaska. There are separate populations in the Gulf of St. Lawrence and the Sea of ​​Okhotsk in eastern Russia. Throughout their range there are various populations that occupy distinct areas of the northern oceans.

Beluga whales live in the White and Kara seas. They often visit shallower coastal areas, but can dive several hundred meters in search of food. The toothed whale is found off the coast of Russia, Canada, Greenland and Alaska. Appears in the eastern part of Hudson Bay, Ungava Bay and the St. Lawrence River.

The beluga whale spends the winter months off the coast of Greenland, and with the onset of warmth, it swims to the western shores of the Davis Strait. There is evidence that whales have been seen off the coast of Scotland in the Edinburgh Strait. Until the middle of the last century, the beluga whale entered the large rivers Ob, Yenisei, Lena, and Amur, sometimes rising hundreds of miles upstream.

Beluga whales are most common in the coastal waters of the Arctic Ocean, but are also found in subarctic waters. Whales migrate south in large pods when the water begins to freeze.

What does a beluga whale eat?

Beluga whales eat a fairly varied diet. They hunt approximately 100 biological species, mainly living on seabed. The beluga whale's diet consists entirely of sea food.

Remains of crustaceans and invertebrates are found in the stomachs of beluga whales:

• Octopuses;
• Cuttlefish;
• Crabs;
• Shellfish;
• Sand worms.

The toothed whale has its own preferences in fish.

The diet includes:

• Capelin;
• Cod;
• Herring;
• Smelt;
• Flounder.

According to data obtained from keeping beluga whales in captivity, they eat from 18 to 27 kilograms of food per day. This is 2.5-3% of their total mass bodies.

Beluga whales usually hunt in shallow water. Its flexible neck allows it to perform complex maneuvers while hunting. Observations show that the beluga whale can take water into its mouth and push it out under strong pressure, just like walruses do. A powerful jet washes out the bottom. The suspension in sand and food rises up. In this way the whale can raise its prey from the day of the sea.

Beluga whale hunts schools of fish. Having gathered in a group of 5 whales or more, beluga whales drive schools of fish into shallow water and then attack. The whale is unable to chew food. He swallows her whole. Teeth are designed to securely hold or tear prey when hunting.

Zoologists also found wood chips, sand, stones and paper in the stomachs of beluga whales. In all likelihood, these elements enter the body of whales during hunting in shallow waters. Whales cannot swallow food whole. Their swallowing apparatus is not suitable for this and they may simply choke. That's why beluga whales hunt small fish, or pinch it off and tear it.

Features of character and lifestyle

Beluga whales are herd animals. They gather in groups of several hundred individuals. There are cases when a colony of beluga whales reached more than a thousand mammals. Beluga whales need air. Whales spend about 10% of their time on the surface.

The whale has well-developed communication abilities. Beluga whales communicate in high frequencies and use echolocation. The sounds produced are harsh and loud. They resemble the calls of birds. For this reason, beluga whales were nicknamed “sea canaries.” Their voices sound like chirps, whistles and screams. The toothed whale is considered one of the loudest in its biological order. It uses vocals during play, mating and communication.

Beluga whales also use body language to communicate and communicate. They give signals, grind their teeth, persistently swim around their relatives, in every possible way attracting attention to themselves or the object that interests them.

Biologists have proven that beluga whales use communication when raising their offspring. They care for, herd and protect their young. In order to protect their offspring they enter the estuaries large rivers where they spend up to several weeks. During this time, they molt and raise their young.

White whales are very curious animals, possessing a lively mind and very smart. I enter into communication with people. They accompany ships, for which they sometimes pay with their lives.

Social structure and reproduction

Mating occurs between February and May. Males attract the attention of females by flirting, racing, playing and diving. At the same time, they make loud sounds, clicking and whistling. In the fight for females, males demonstrate their strength and superiority to their rivals. Males use tail slaps in the water, head shaking, sharp intimidating sounds and body language. They cut off the opponent with a sharp tilt of the body, block the road and demonstrate in every possible way that the territory is closed.

The decision to mate is made by the female. The caress of white whales is a beautiful sight. The couple plays, swims synchronously and touches their bodies. Offspring appear between March and September. Pregnancy lasts 400-420 days. Zoologists are confident that female white whales are capable of slowing down the gestation and birth of their calves. This assumption is made on the basis that births in the group occur almost at the same time. Since the process of conception is difficult to synchronize, the theory of fetal growth inhibition has arisen.

Newborn white whale calves weigh about 80 kilograms. The color of the babies is blue or gray. Calves stay with their mother for at least two years. All this time they are fed with milk. Lactation in a whale lasts from 1.5 to 2 years. Newborn babies are between two females: a mother and a teenage nanny. The cub is looked after, protected and lifted for a breath of air.

Whales reach sexual maturity at 4-7 years. Their maximum lifespan is 50 years. It is believed that females live on average up to 32 years, males up to 40.

Natural enemies of beluga whales

In nature, the beluga whale has a lot of enemies. Typically it is more large predators both underwater and on shore. The nature of the predator, size and number depend on the beluga whale’s habitat. These include killer whales, polar bears, and Greenland sharks.

Beluga whales are very easy prey for polar bear. A white whale comes close to icebergs where hunting bears are located. Sometimes bears come to migrating ice specifically to hunt, and sometimes they stay on it for several days. Polar bears They track beluga whales and attack using their claws and teeth.

Interesting fact: The beluga whale has several options for protection - camouflage, the ability to hide in the ice and behind a larger fellow tribesman who is able to repel a predator's attack.

Killer whales have a different way of hunting. As a pod of white whales begins their migration, the killer whale joins the group and accompanies it most of the way, constantly attacking and feeding. Beluga whales can usually hear killer whales, making it difficult to attack them. Due to the low maneuverability of killer whales in the ice, beluga whales manage to evade their pursuers.

Greenland sharks chase a school and attack not only during migration, but also in their habitats. However, white whales are capable of collective resistance. Animals often find themselves captured by Arctic ice and die, becoming prey to polar bears, killer whales and the local population.

People remain the most important danger and threat to the survival of the species. Hunting in industrial scale for the skin and fat of the whale significantly reduced the number of the animal. The main danger to these whales is toxic and industrial waste, garbage, and climate change and environment in breeding and habitat areas.

Scientists note that beluga whales are affected by noise pollution. The sharp growth and development of shipping, the increase in the flow of wild tourists interferes with normal reproduction and leads to a decrease in the number of calves, and as a result, a reduction in the herd.

Population and species status

Estimates of beluga whale abundance vary widely. The difference in numbers is tens of thousands. This is a fairly large error for such a small species.

The current worldwide population is between 150,000 and 180,000 animals. 30 toothed whale habitat sites have been noted - 12 are located in the territory Russian Federation. Most large group whales - more than 46% - are constantly located off the coast of Russia.

Habitats of the main population:

• Bristol Bay;
• Eastern Bering Sea;
• Chukchi Sea;
• Beaufort Sea;
• Severnaya Zemlya;
• West Greenland;
• Western, Southern and Eastern Hudson Bay;
• St. Lawrence River;
• Spitsbergen;
• Franz Josef Land;
• Ob Bay;
• Yenisei Bay;
• Onega Bay;
• Dvinskaya Bay;
• Laptev sea;
• Western Chukchi Sea;
• East-Siberian Sea;
• Anadyr Bay;
• Shelikhov Bay;
• Sakhalin - Amur River;
• Shantar Islands.

Canadian ichthyologists count between 70,000 and 90,000 beluga whales in their region. The western Hudson Bay population is considered the largest in Canadian waters, with approximately 24,000 individuals. Beluga whales living in this part of the bay are considered resistant to external factors, despite the aggressive environment and human interference in the life of the toothed whale.

Migrating populations are counted simultaneously by representatives different countries— Denmark, Norway, Russia, Canada and Great Britain. Their number at the starting point is very different from the finishing point. The numbers reflect group losses from predation and human activity.

A fairly large group of animals lives in zoos, oceanariums, national aquariums and dolphinariums. Scientists are at a loss as to how many individuals may be in captivity. According to some estimates, this could be 100 or more animals in Russia alone, and about 250 individuals in other countries of the world.

Beluga conservation

The white toothed whale is listed in the Red Book as an endangered species. Industrial fishing is on the list of threats, external factors and human waste. Arctic indigenous populations in Alaska, Canada, Greenland and Russia hunt beluga whales. The number of animals killed is about 1000 per year. In Alaska there are between 300 and 400 killed, in Canada between 300 and 400. Until 2008, the International Union for Conservation of Nature (IUCN) classified the beluga whale as "vulnerable." In 2008, the IUCN classified it as "imminently threatened" due to its decline numbers in some parts of the range.

Beluga whales, like most other Arctic species, are facing habitat changes due to climate change and melting Arctic ice. It is still not entirely clear why beluga whales use ice, but it is assumed that this is a place of refuge from predatory killer whales. Changes in Density arctic ice caused massive losses among individuals. Sudden changes in weather can cause the ice cracks that whales use to access oxygen to freeze, eventually leading to the whales' death from asphyxiation.

The US Congress passed the Protection Act marine mammals prohibiting the harassment and hunting of all marine mammals in U.S. coastal waters. The law has been amended several times to allow Indigenous peoples to hunt for subsistence, temporarily capturing limited numbers for research, education and public display. Commercial whaling has put whales at risk of extinction in areas such as Cook Inlet, Ungava Bay, the St. Lawrence River and western Greenland. Continuation of whale hunting by indigenous peoples could mean some populations will continue to decline

Belukha- a unique animal that has gone through a complex chain of evolution. Scientists were able to find out that the ancestors of the modern white whale once lived in warm seas, and before that on the surface of the earth. This fact is proven by fossils found in northern California, as well as the bones of a prehistoric animal discovered in Vermont, USA. The remains rested 3 meters underground and 250 km from the nearest ocean. DNA analysis matched the code of a modern beluga whale. This proves that her ancestors came out of the ocean and then returned to aquatic environment a habitat.

The beluga whale belongs to the order Cetacea, the family Narwhals (Monodontidae). The scientific name of the beluga whale is Delpbinapterus leucas, which means “dolphin without a wing.” People call her the white dolphin, polar dolphin, as well as a singing whale.

Along with its closest relative, the narwhal, the beluga whale is one of the most social cetaceans. A huge concentration of snow-white animals in an Arctic bay is an unforgettable sight.

Features of the appearance of beluga whales

Beluga whales are large animals: their body length is 3-5 meters, weight is 500-1500 kg. Males are approximately 25% longer than females and almost twice their mass.

Newborn whales are brown, then they gradually become lighter in color, becoming grey colour. Adults are white or slightly yellowish.

A characteristic feature of belugas is their flexible neck, thanks to which they, unlike most cetaceans, are able to turn their heads from side to side.

Another feature is the absence of a dorsal fin. Instead, beluga whales have a crest along their back (from the middle of the body to the tail).

It is noteworthy that the beluga whale can change the expression of its “face”. When the whale is calm, it appears as if it is smiling. But what is especially impressive is the demonstration of an open mouth with 32-40 teeth.

Their teeth emerge only in the second or third year of life, and it is possible that their main function is not chewing food at all. Beluga whales often click their jaws, and the teeth can be used to produce a louder sound. In addition, they like to show off their “smile” to their relatives.

Adults have a well-defined melon (a rounded pad of fat on the forehead), but it develops slowly, and is completely absent in newborns. In one-year-old cubs, the melon is already quite large, but weakly separated from the snout. Only by the age of 5-8 years (it is at this time that puberty begins) does the fat pad take on its usual shape.

Melon is used to focus sounds during echolocation. This ability is vital for orientation and search for prey in muddy water or in the dark.

Nature took care that the beluga whale did not freeze in cold water, providing it with a layer of fat. Moreover, this layer is so thick that the head seems too small for such a body.

Habitat

In prehistoric times, beluga whales lived in the waters temperate zones. Today they live only in the cold Arctic seas of northern Russia and North America, as well as in Greenland and Spitsbergen. They are found both in coastal waters and in the open ocean, and in summer in river estuaries.

In the Beaufort Sea, during their eastward migration, beluga whales stop for about a week in the vast Mackenzie River Delta before continuing their journey. In some areas, such as Svalbard, whales come to the base of the glaciers.

Lifestyle

Beluga whales spend most of the year away from the coast, in areas with a lot of ice, and sometimes in large holes in the pack ice.

From June to September, these whales gather in the hundreds in wide river estuaries. At this time, they shed: the old yellowed skin peels off, replaced by new shiny white skin.

The most sociable whales

Singing whales are one of the most social animals among cetaceans. They are rarely seen alone. Congregations of hundreds or thousands of beluga whales are quite common and often cover an area of ​​many square kilometers. The aggregation appears to behave as a single unit, but when viewed from above, it appears to be made up of many smaller groups, usually containing individuals of the same size or sex. Females and cubs gather together, large adult males also form separate groups.

Beluga whales communicate with each other through sound signals and facial expressions. They make a wide variety of sounds, including mooing, chirping, whistling, grinding, etc. Underwater, the sounds of a herd of these whales resemble the noise of a barnyard. Some of the acoustic signals they emit can be heard above water.

Movable mouth and neck allow belugas to communicate with each other and through facial expressions.

What do beluga whales eat?

The diet of beluga whales is quite varied. They feed on all kinds of schooling fish, flounder, various worms, shrimp, crustaceans and mollusks.

Singing whales usually hunt near the bottom at depths of up to 500 meters. They can dive to depths of over 1000 meters; they are limited only by the duration of the breathing pause, which is normally 10-20 minutes.

Movable neck allows cetaceans to scan visually and acoustically large area bottom surface. They can both suck in water and release it in a stream in order to get a hidden victim from a shelter.

Reproduction

Pregnancy lasts 14-15 months. Childbirth most often occurs at the beginning of summer, when the sea ice breaks up. Usually one cub is born; twins are extremely rare.

Immediately after birth, a strong bond is established between mother and baby. The baby can feed on mother's milk for more than two years. All this time, mother and baby are practically inseparable. The complete reproductive cycle of pregnancy and lactation takes 3 years or more.

Conservation of beluga whales in nature

Beluga whales return to their summer habitats along the same routes, even if they are hunted there. This persistence has made this species particularly vulnerable. They are so conservative in their preference for familiar migration routes and breeding sites that they do not colonize vacated territories where the population has been exterminated. One such place is Ungava Bay on the Labrador Peninsula. Previously, beluga whales were quite numerous here, but today they are practically never found.

In XYIII and 19th centuries American and European whalers drove hundreds of belugas ashore. The indigenous population also hunted them, but in the past they hunted relatively small numbers of animals without causing significant harm to the population. Modern Eskimo hunters are equipped with rapid-fire rifles, harpoon guns and motor boats, so such hunts can seriously undermine cetacean populations.

Currently, the number of beluga whales worldwide is estimated at approximately 100 thousand, and the total annual catch ranges from hundreds to several thousand individuals. But the greatest concern is the degradation of beluga whale habitats due to the development of oil fields and the construction of hydroelectric power stations, although global warming may also become a problem in the future.

In contact with

Delphinapterus leucas Pallas, 1776

Squad: Cetaceans (Cetacea)

Suborder: Toothed whales (Odontoceti)

Family: Narwhals (Monodontidae)

Genus: Beluga whales (DelphinfpterusLaceped.1804)

Other name:

Belukha, Beluga (equivalent, the first is most common)

Where he lives:

The beluga whale population is divided according to its flying areas into 29 local herds, of which about 12 are located in Russia. Distributed circumpolarly, between 50° and 80° N, inhabiting all Arctic, as well as the Bering and Okhotsk seas; In winter, visits to the Baltic Sea are known. In pursuit of fish (salmon at spawning), beluga whales entered the big rivers(Ob, Yenisei, Lena, Amur), sometimes rising upstream for hundreds of kilometers.

Size:

Beluga whales are characterized by sexual dimorphism: males are usually larger than females of the same age. Weight: males reach 850-1500 kg, females 650-1360 kg with a typical body length of 3.6-4.2 m. The largest males reach 6 m in length and 2 tons in weight.

Appearance:

The beluga's head is spherical, "lobed", the lower jaws practically do not protrude forward without a beak. The vertebrae in the neck are not fused together, so the beluga whale, unlike most whales, is able to turn its head. This makes it easier for her to navigate and maneuver in ice. The pectoral fins are small and oval in shape. The dorsal fin is absent - this allows the beluga to move more freely under the ice. From here Latin name genus Delphinapterus leucas - "white dolphin without a dorsal fin."

The skin with a loose layer of epidermis (up to 12 mm thick) resembles an external shock absorber and partly protects beluga whales from damage when swimming among the ice. They are saved from hypothermia by a layer of subcutaneous fat up to 10-12 cm thick, in some places up to 18 cm, which is up to 40% of the beluga whale’s body weight. The skin color is monochromatic. It changes with age: newborns are light brown due to a thick layer of epidermis, which, as the baby grows, falls off in pieces and the lower parts of the dermis rise to the surface with an abundance of dark pigment - melanin. The general coloration becomes dark blue, growth and molting continue and the young become gray, then bluish-gray; individuals older than 4-7 years are pure white.

Behavior and lifestyle:

Some beluga whale populations undergo regular migrations. They are associated with the seasonal movements of schools of fish. Thus, the movement of the beluga whale population from Cook Inlet in Alaska repeats the movement of its main prey - salmon.

In spring, beluga whales begin to move to the shore - to desalinated shallow bays, fjords and the mouths of northern rivers. Flying off the coast is determined by the presence of food and more. high temperature desalinated water. The latter improves the conditions for molting and shedding the old layer of epidermis. Often, in order to remove the dead surface layer of skin, beluga whales rub against the bottom - sand in shallow water. Beluga whales are attached to the same flying areas, visiting them from year to year. Tracking individual individuals has shown that beluga whales remember their birthplace and the route to it after wintering.

Local herds in summer (reproductive aggregations) play a dual role in the biology of the species. Firstly, they ensure population reproduction and isolation from neighboring local herds, and secondly, they play vital role in terms of implementing all types of individual contacts (sexual, play, etc.) between members of the herd, maintaining hierarchical relationships and promoting the upbringing and training of young animals. This ensures the preservation of the social structure of the local herd and the individual and group status of its members.

Not all populations migrate. Their necessity is determined by specific ice conditions and the presence of food accumulations.

IN winter time Beluga whales, as a rule, stick to the edges of ice fields, but sometimes penetrate far into the glaciation zone, where winds and currents support cracks, leads and polynyas. When large areas become icy, they make massive migrations from these areas. The polynyas to which belugas come up to breathe can be several kilometers apart. Beluga whales find them using direction finding and sometimes location. But sometimes they find themselves trapped - in ice captivity, if the distance to clean water exceeds 3-4.5 km. The dorsal part of the body and the upper part of the head consist of thick and durable skin, which allows them to be used to support wormwood, breaking ice up to 4-6 centimeters thick.

Beluga whales are social animals. The beluga whale herd consists of clans, and clans are made up of families organized on the principle of matriarchy. The family consists of primary family groups: mother and 1-2 cubs. Males in the herd and clan play the role of guards and scouts for fish accumulations. At large concentrations of fish, several herds of beluga whales sometimes gather, and the feeding animals gather in herds numbering hundreds and even thousands of animals.

Nutrition:

The basis of the beluga's diet is fish, mainly schooling fish (capelin, cod, cod, herring, navaga, flounder, whitefish and salmon species); V to a lesser extent- crustaceans and cephalopods. Beluga whales do not grab prey, especially benthic organisms, but suck it up. An adult consumes about 15 kg of food per day. But such lucky days rarely fall out.

Reproduction:

In the Sea of ​​Okhotsk, mating in beluga whales occurs in April - May, in the Gulf of Ob - in July, in the Barents and Kara Seas - from May to August, in the Gulf of St. Lawrence - from February to August, and in Hudson Bay, fertilization of females occurs from March to September. Thus, the mating period lasts about 6 months, but the bulk of females are fertilized in a relatively short time - late April - early - mid-July. During the rest of the year, in most cases only individual animals mate.

The childbearing period is extended, as is the mating period, and childbirth can occur starting from early spring throughout summer months. Thus, pregnancy in beluga whales lasts 11.5 months; there is an opinion that this period can reach 13-14 months. As a rule, females give birth at the mouths of rivers that bring more warm waters. The female brings one cub 140-160 cm long, very rarely - two. The lactation period lasts about 12 months. The next mating can occur one to two weeks after birth.

Lifespan:

Life expectancy in nature is 32-40 years (known maximum age females - 44 years old).

Number:the exact number is not known.

According to information International Union Nature Conservation, there are about 150,000 beluga whales in the world. Russian populations, according to the International Whale Commission, number up to 27,000 individuals. At the same time, the 3 largest groups of the Sea of ​​Okhotsk number up to 20,000 beluga whales.

Natural enemies:

The enemy of beluga whales is the killer whale.

Threats to the species:

The main danger for these whales is toxic waste that pollutes their habitat, as well as industrial displacement from their Arctic habitats, especially key areas - breeding and feeding areas. IN last years Noise pollution has sharply increased - due to the development of shipping and an increase in the flow of wild tourists, which interferes with normal reproduction and leads to a decrease in the number of cubs - i.e. reduction in herd size.

Interesting Facts

IN winter period The beluga whale hunts cod, flounder, goby, pollock, making very deep dives - up to 300-1000 m, and remaining under water for up to 25 minutes. Despite its massive size, the beluga whale is distinguished by its agility; she is able to swim on her back and even backwards. Usually swims at a speed of 3-9 km/h; when frightened, it can make jerks of up to 22 km/h.

For the variety of sounds they made, whalers in the 19th century. The beluga whale was nicknamed “the canary of the sea” ( sea ​​canary), and the Russians developed the expression “beluga roar” - the characteristic roar of a male during the rut.

Researchers counted about 50 sound signals from belugas: whistling, squealing, chirping, squealing, grinding, piercing scream, roar and others. In addition, beluga whales use “body language” (slapping the water with their tail fins) and even facial expressions when communicating.

In addition to screams, beluga whales emit clicks in the ultrasonic range. A system of air sacs in the soft tissues of the head takes part in their production, and the radiation is focused by a special fat pad on the forehead - a melon (acoustic lens). Reflected from surrounding objects, the clicks return to the beluga; serves as an “antenna” lower jaw, transmitting vibrations to the middle ear cavity. Echo analysis allows the animal to get an accurate picture of its surroundings. The beluga whale has excellent hearing and echolocation. These animals are capable of hearing in a wide range of frequencies from 40-75 Hz to 30-100 kHz.

The beluga whale also has well-developed vision, both under water and above its surface. The beluga whale's vision is probably colored, because... its retina contains rods and cones - photoreceptor cells. However, studies have not yet confirmed this

Compiled by: Member of the Board of the Marine Mammal Council,

Head Laboratory of Marine Mammals IO RAS, Doctor of Biological Sciences V.M. Belkovich

Quite a peaceful and interesting animal. They live in the cold waters of the Northern Arctic Ocean, in the Bering Sea, Baltic Sea and Okhotsk Sea.

Chasing schools of fish, they swim to the mouth of the rivers - Amur, Yenisei, Ob. They migrate, traveling long distances to shores and shallow bays in the spring. There is an abundance of food here at this time. In autumn they return to their usual habitats.

The body length can reach 6 meters, and the weight reaches 2 tons. Females are smaller than males in size and weight.

The head is small, but unlike many of its representatives of the cetacean order, it can turn it to the sides, thanks to the cervical vertebrae, which are not fused together.

Oval pectoral fins small, dorsal and is completely absent. The muzzle is cute, looking at it you might think that this giant is always in a good mood.

The skin is dense, pure white, which is why it attracts attention to itself even more and has a positive attitude. The teeth are 5 cm long, sharp, located in tens on the upper and lower jaws.

They feed mainly on fish - herring, capelin, navaga, cod and the like. All these fish swim in large schools, which is beneficial for the beluga whale. It sucks water into itself, thereby drawing in a certain number of fish. And the big beauty eats about 15 kg a day.

Whales often drive a school of fish into shallow water, hunting in a group, because it’s easier to catch fish and get enough faster. It feeds its body with crustaceans and cephalopods.

These are friendly and sociable animals. They can make a lot of sounds, thereby transmitting information to each other, practically singing. She whistles, chirps, roars and screams, and can even squeal, grind and click.

They also express emotions through body movements. Smart, beautiful. Excellent virtuoso swimmers, they can swim on their backs and even backwards. Their usual speed of movement is 4 -8 km/h. If you need to escape, for example, from a killer whale, then you can turn on the acceleration up to 20 km/h.

They live in small groups that form herds. Several females, usually 3, with cubs are one group, and the second are males, there can be up to 13 individuals. In winter, they try to stay near the edges of the ice, because they need air.

A beluga whale can survive under water for no more than 15 minutes. If the holes are covered with ice, then the body blows through the armor. It also happens that the layer of ice is too thick and it is impossible to break through it. We must either look for another place, or the animals will die.

T a thick subcutaneous layer of fat helps them not to freeze. A cunning polar bear often watches near the holes of beluga whales, stuns the animal with a blow from his paw and takes out a trophy. In addition to the polar bear, the enemies of beluga whales also include the killer whale.

The mating and breeding season for belugas lasts from spring to autumn. They migrate to shallow waters. Males compete for females, who bear offspring first. Two weeks after the birth of the cub, she can give consent to courtship. In addition to calling calls, beluga whales rub their noses and sides against each other as a sign of affection.

Pregnancy lasts a long time - 14 months. One, or less often two, babies are born. The length of the newborn is 1.5 meters, its skin is dark blue. Having taken his first breath with the help of his mother or aunts, the little one is nourished with milk. The whole group welcomes him and rejoices at the birth of the cub.

He will feed on mother's milk until he is 2 years old. At the same time in summer, animals molt. They slide their bodies over small stones to facilitate and speed up the skin renewal process. Beluga whales take 11 years to grow. In one year the color of the cub will change from blue to light blue. And it will become pure white only after 5 years.