Whales. Mammals. Order Cetacea (Cetacea) Whale, sea dweller or whale, mammal

Blue whales are the largest animals on our planet: adults range from 24 to 30 meters in length, while females can exceed the size of males by up to 10 meters. In the XX century. they were almost completely exterminated due to commercial fishing. And only after a general ban on the destruction of whales did their numbers begin to gradually increase.

The upper part of the whale is a mottled blue-gray color, while the lower part is light gray or yellow-white. The yellowish tint of the animal's abdominal part is given by growths of microscopic unicellular seaweeds called diatoms. These plants are common in cold sea waters.

It is officially believed that the largest individual was a female, which was caught by whalers in the last century, 23 m 58 cm long. These animals can weigh up to 200 tons. For comparison, the weight of an African elephant is 7.5 tons. The heart of a blue whale is the size of a car, the beat of which can be heard 3 kilometers away. One of the species is the pygmy blue whale. They are three meters shorter than their larger relatives.

These animals have one incomparable quality: blue whales are the loudest animals on earth. The volume of their call signs reaches 188 decibels, which is significantly higher than the sound of a jet engine - 140 decibels. An animal can hear the song of a relative at a distance exceeding 1.5 thousand km.

In addition to their enormous size, the distinctive features of blue whales are a relatively small dorsal fin, a rounded part of the front of the skull and about 90 longitudinal grooves on the belly, reaching the navel.

Features of communication

Blue whales travel alone for most of their lives, sometimes in groups of 2-3 individuals. Large flocks, which may include 60 animals, have been recorded in places where food accumulates.

But there is one “but” here. The blue whale has the strongest voice of all animals, the low frequencies of which can spread in the deep-sea environment for many hundreds and even thousands of kilometers. Therefore, what may seem to people like “solo” sailing, in reality, is not so. Thanks to the ability for such negotiations, a solitary whale is often in close contact and communication with its relatives.

Nutrition

Whales feed by diving every 10-20 minutes to a depth of about 100 meters. The stomach can hold about one ton of krill at a time. Its requirement for krill is about 4 tons daily during the summer feeding season.

In the mouth there is a so-called “whalebone” of black color. These are horny plates hanging from the upper palate, 300-400 pieces each. from each side. The length of the plates ranges from 50 cm in front to 100 cm in the back. To feed, the animals straighten the “whalebone” in their throats and take in water with krill, sifting it through the horny plates. The water is then released through the baleen and the remaining krill in the mouth is swallowed.

Life cycle

The female usually gives birth to one kitten every two to three years. Currently, this birth rate exceeds the rate of destruction of animals during hunting, which continues to this day.

At birth, the baby whale is the largest newborn animal on earth: it is 8 meters long and weighs about 4 tons. In this case, the female’s pregnancy lasts a year, and usually one baby is born. The cubs grow at a rate of 90 kg per day. Childhood ends at 7-8 months, after the animal reaches 15 m in length and learns to swim independently. Animals reach maturity at 5–10 years.

The growth rate of the blue whale is also amazing and is the highest in the animal kingdom. In just a year and a half, the size of tissues increases several billion times.

Like other cetaceans, blue whales do not have teeth. Therefore, it can be difficult for scientists to determine the age of an animal. It is believed that their average lifespan reaches 50 years, some individuals can live up to ninety, and the oldest animal is considered to have died at the age of 110 years.

Extermination of whales

Before the start of active whaling, the population of blue whales exceeded 250 thousand individuals. But in the 20th century. due to merciless hunting they were almost exterminated. Between 1904 and 1967, more than 350 thousand individuals were killed in the southern hemisphere alone. Many animals also died at the hands of Soviet whalers between 1960 and 1970.

The whales suffered especially hard in 1931, which marked the heyday of the fishery. This year, in just one whaling season, more than 29 thousand blue whales were killed. And only in 1967 the situation began to improve, when the world community stood up to protect animals, and whaling was banned.

Population today

Today, blue whales are distributed throughout the world. Their habitat includes all the world's oceans, with the exception of the Arctic Ocean. Blue whales are one of the most rarely seen species of cetaceans. Scientists still haven’t decided how many there are on earth. Their number ranges from 10 to 25 thousand.

One of the many populations of these animals that continues to grow at an encouraging rate is the population of whales that live in the North Pacific Ocean near the US state of California. The number of its representatives reaches 2 thousand.

This species, known as pygmy whales or pygmy whales, lives mainly in the Indian Ocean. Recent research suggests that these animals live in other areas of our planet.

Blue whales prefer to swim in deep ocean waters. In summer they migrate towards the poles, into cooler waters. In winter, the animals swim back towards the equator to warm waters to breed. Due to the fact that the seasons in the northern and southern hemispheres are opposite in time, populations of representatives living in different parts of the planet do not communicate or mix with each other.

Danger to whales

Most biologists have concluded that blue whales are the most endangered of all cetaceans. A serious danger for them is:

water pollution with chemicals;
a violation of the natural sound balance, due to which they are unable to find a mate;
loss of permanent habitat;
collisions with ships and entanglement in fishing gear.

Climate change could have a significant impact on food supplies, as global warming could shift the pH balance of seawater to acidic levels. This will affect the number of krill that the blue whale feeds on.

Due to climate changes in the frontal zones, the habitats of blue whales, there is a shift further south. In frontal zones, water can rise from the depths, bringing with it gigantic amounts of nutrients. This stimulates the growth of phytoplankton, and also creates conditions for the growth of populations on which the animals feed.

As a result of the migration of frontal zones over a distance of 200-500 km, blue whales are forced to migrate further to feed. Over time, such movements can significantly reduce the body's energy reserves and shorten the feeding seasons. As frontal zones move south, they reduce the areas where species of animals that provide food for blue whales can develop.

Representatives of the class of mammals - whales - are marine animals that amaze with their impressive size. In Greek, the meaning of the word kitoc is “sea monster”, from which the name of this mammal comes from. At a time when fishermen had just begun to notice such a large creature as a whale, there were frequent disputes about whether it was a fish or an animal. Surprisingly, the ancestors of all cetaceans are artiodactyl land animals. Although the whale looks like a fish in appearance, one of its modern ancestors is a hippopotamus. Despite all these facts, debate continues about what whales are - fish or mammals.

Whale - description and characteristics

The size of whales exceeds the dimensions of any mammal: the body length of a blue whale reaches twenty-five to thirty-three meters, its weight is more than one hundred and fifty tons. But there are also smaller, dwarf whales. Their weight does not exceed four tons, and their body length is six meters.

All cetaceans have a body shaped like an elongated drop, which allows them to glide easily in the water column. The large head with a narrow and blunt rostrum allows the whale to cut through the water when swimming. The nostrils are shifted closer to the crown, and the eyes are small relative to the body. Different individuals have differences in the structure of their teeth. Toothed whales have sharp cone-shaped teeth, and baleen whales, instead of the usual teeth, filter water and thus obtain food using bone plates (or whalebone).

The whale's skeleton provides special plasticity and the ability to perform maneuvers due to the spongy structure and elasticity of the intervertebral discs. The head goes into the body without a neck interception; towards the tail the body becomes narrower. The mammal turns and slows down with the help of flippers, which have been transformed from pectoral fins. The motor function is performed by the tail, which is distinguished by its flat shape, extreme flexibility and developed muscles. At the end of the tail section there are horizontally arranged blades. Many whales use their tail to stabilize their movements underwater.

Hairs and bristles grow only on the faces of baleen whales; the body is covered with absolutely smooth and hairless skin. The color of the animal's skin can be monochromatic, anti-shadow - dark top and light bottom, or spotted. As whales age, they can change the color of their skin. Cetaceans lack olfactory receptors and also have poorly developed taste receptors. The whale can only distinguish the taste of salty foods, while other mammals have a full range of taste buds. Poor vision and frequent myopia are fully compensated by the conjunctival glands. Mammalian hearing distinguishes sounds ranging from muffled noises to ultrasonic frequencies, due to the complex anatomical structure of the inner ear. There are a large number of nerves under the skin, which provides the animal with an excellent sense of touch.

Whales communicate with each other using echolocation. The absence of vocal cords did not prevent the whale from communicating with other individuals by producing sounds. The role of a reflector and a sound lens is performed by a layer of fat in the concave bones of the skull. Whales have slow, smooth movements, but sometimes their speed can reach forty kilometers per hour.

The body temperature of a whale does not depend on the environment; these are warm-blooded animals. A thick layer of fat protects cetaceans from hypothermia. Huge lungs with well-developed muscles allow animals to spend under water from ten minutes to an hour and a half. Swimming to the surface of the ocean, the whale releases air whose temperature is much higher than the surrounding air. That is why, when exhaling, a fountain appears - a sheaf of condensate, and along with it, due to the high power, a trumpet roar breaks out in some large animals.

Lifespan. How long do whales live?

The question of how long whales live can be answered differently depending on their species. Small animals live up to thirty years, the lifespan of large whales does not exceed fifty years.

The habitat of whales is the world's oceans. Mammals are scattered across all latitudes, but in cold times the majority migrate to warm waters and live near the coast. These are herd animals that prefer to live in groups with several dozen or hundreds of individuals. Whales migrate depending on the season. In winter and during the birthing period, whales and their females swim to warm waters, and in summer they are in waters of temperate or high latitudes.

A whale's diet depends on its species. Plankton is preferred by planktivores; mollusks act as food for teutophages. Ichthyophages feed on live fish; detritivores consume decomposed organic matter. Killer whales are the only cetaceans that hunt not only fish, but also pinnipeds such as seals, penguins and sea lions. Dolphins and their offspring can also become victims of killer whales.

Types of whales

The largest representative of the mammal family is the blue whale. One hundred and fifty tons of weight and a length of thirty meters give the blue whale the right to be considered the largest animal on the planet. The narrow head and slender body allow the mammal to move smoothly under water, cutting through its thickness. The skin has the appearance of marble stone thanks to the gray spots scattered throughout the blue body of the whale. The blue whale lives in every ocean and feeds mainly on plankton and small fish. Blue whales prefer to live and move alone. The size of the blue whale attracts poachers and scientists to it.

The blue whale dives into deep water in moments of fear or injury. Whalers, using harpoons, measured the maximum depth to which the animal descends - five hundred and forty meters, although during a normal dive a whale does not descend into water deeper than one hundred meters. After a deep dive, the mammal makes a series of surfacings in order to inhale air. The length of the blue whale makes it dive and emerge rather slowly. The animal spends three quarters of its life under water. The blue whale reproduces more slowly than other cetaceans: calves are born no more than once every two years. During one birth, only one baby is born, and the pregnancy period itself is very protracted.

The animals were practically exterminated in the last century, so now scientists are trying to increase their numbers. Today, the number of blue whales across the planet does not exceed ten thousand individuals. Poachers destroy blue whales because of the value of their baleen. It has a rich pitch black color and a triangular shape. The fringe located on the baleen plates allows the whale to feed on large crustaceans and small plankton.

The songs of an animal like the blue whale are considered very depressing. The blue whale lives about eighty to ninety years, the maximum recorded age of the animal is one hundred and ten years.

Because of the convex hump-shaped fin on the back, one of the whale representatives was called humpback. The animal has a short body - at least fourteen meters, while its mass is about thirty tons. The humpback whale differs from other species in the form of a variety of skin colors and the presence of several rows of warty, leathery growths on the top of the head. The body color of the mammal can vary from brown to dark gray and black, the chest and belly are covered with white spots. The upper part of the fins can be completely black or covered with light spots, the bottom is completely white. The animal has long pectoral fins, the mass of which makes up a third of the whale's total weight. Humpback whales have individual growths as well as coloration.

This mammal lives in the waters of all oceans, excluding the areas of Antarctica and the Arctic. Migration of the humpback whale can be either localized or seasonal, depending on the availability of food or ocean water temperature. Animals do not choose specific areas to live, but prefer to be near the shore, in shallow water. During the migration period, whales enter deep waters, but usually stay near the shores. At this time, mammals hardly eat, feeding on reserves of subcutaneous fat. Crustaceans, mollusks and small fish make up the diet of the humpback whale in the warm season. Groups of these animals quickly disintegrate. Only mothers and cubs can swim and hunt together for long periods of time.

The humpback whale is known for the sounds it makes. During the breeding season, males make long-lasting sounds, reminiscent of melodic songs, attracting females. Scientists who became interested in these sounds, through research, were able to determine that the songs of the humpback whale, like human speech, consist of individual words that form sentences.

The pygmy whale is considered the smallest species of cetacean. Its mass does not reach three tons, and its body length does not exceed six meters. This is the only whale that moves in waves. The dwarf whale has a streamlined body with a gray or black color with gray spots. The animal’s head is completely free of any growths, the pectoral fins are very short, have a rounded shape, and the sickle-shaped dorsal fin does not exceed twenty-five centimeters in height. Unlike blue, the dwarf whale has a white baleen with a yellowish tint.

Scientists provide little information about the lifestyle of this animal, as it is rare. The dwarf whale does not jump out of the water and does not raise its tail fin above its surface. The fountains that he releases when exhaling are not striking in their size and are not accompanied by a hum. The mammal can be distinguished by its light gums and a white spot on the jaw. The dwarf whale swims rather slowly, bending its body in waves.

The mammal leads a solitary lifestyle, but sometimes it can be seen in groups of sei whales or minke whales.

These whales are rarely found in the open ocean; they often swim in shallow bays. During the warm season, young pygmy whales move to coastal waters. Animals do not migrate long distances. Plankton, crustaceans, and invertebrate marine animals act as food for dwarf whales. This is the rarest and smallest species of cetacean.

One of the representatives of cetacean mammals is the beluga whale. The name of the animal comes from its color. Beluga whale calves are born with dark blue skin, which then changes to light gray, and adults are pure white. The animal is distinguished by a small head with a high forehead. The beluga whale can turn its head because its cervical vertebrae are not fused. Most whales do not have this ability. The animal has no dorsal fin, and the small pectoral fins are oval in shape. Because of these features, the name of the mammal is translated from Latin as “wingless dolphin.” Thirty to forty years is how long these whales live.

These whales live in Arctic latitudes, but migrate seasonally. Beluga whales spend summer and spring off the coast, in areas for molting and feeding. During the molting season, whales rub in shallow water against sea pebbles, thus trying to shed their old skin. Every year the beluga whale visits the same places, remembering the place of its birth, where it returns after wintering. In winter, whales live in glaciated zones, breaking through thin ice with their powerful backs. But at moments when ice holes are covered with a thick layer of ice, beluga whales can become captured by ice. The danger comes from polar bears and killer whales, for which beluga whales can become food. Whale migration takes place in two groups: one contains several females with calves, and the second contains adult males. Communication between individuals is carried out using sound signals and clapping of fins in the water. During the study of beluga whales, more than fifty types of sounds that it makes were counted.

Mating of whales takes place on the coast, several times a year. Males can organize tournament fights for a female. During birth, one baby whale appears, which the female feeds for one and a half to two years.

One of the brightest cetaceans is the sperm whale. Unlike other whales, sperm whales prefer a gregarious lifestyle, moving and hunting in groups of hundreds of individuals. Their speed does not allow sperm whales to move quickly through the water column. The sperm whale is known for its ability to dive deep underwater and stay at depth for a long time. The large content of fat and fluids in the sperm whale's body provides it with protection from water pressure. The mammal stores its air supply in the air sac and muscles containing a large amount of myoglobin. In rare cases, the animal has caused accidents with deep-sea cables. The sperm whale got entangled in the cable with its tail and lower jaw and choked, this was discovered already during the repair of the cable. A sperm whale was recovered off the coast of the Iberian Peninsula after it became entangled in a cable located at a depth of more than two thousand meters. At the same time, the whale uses echolocation, emitting ultrasound, which not only allows it to communicate with other sperm whales, but also to scare away dangerous animals. High-frequency signals block the movements of other ocean inhabitants, which makes it easier for the sperm whale to hunt them.

This mammal has been exterminated for several centuries, which is why its numbers have sharply declined. In conditions of polluted ocean waters and continued fishing, sperm whales are very slowly restoring their population. When wounded and attacked, the animal shows great aggression, so hunting it involves great risk. A wounded sperm whale is capable of sinking a whaling ship along with its entire crew. What does a whale eat? It eats small crustaceans, mollusks, squid, octopuses, and small sharks. To grind food, the sperm whale swallows small stones. This whale is the only mammal in whose mouth a person can completely fit. During whaling ship accidents, sperm whales swallowed whalers.

Many researchers are still arguing about whether the killer whale is a whale or a dolphin. Although the killer whale is called a killer whale in the media and in the everyday life of whalers, this animal belongs to the dolphins. This animal is confused with a whale because of the shape of the fin: dolphins have sharp, long fins, while killer whales have rounded and wide fins.

Mating and reproduction of whales

The whale is a monogamous animal that reproduces once every two years. The mammal fully matures by the age of twelve, but it becomes able to reproduce by the age of four. Males mate throughout the whole year, so the mating season is very long. Pregnancy depends on the species of cetacean and can take from seven to fifteen months. To give birth, females migrate to warm waters.

As a result of the birth, one whale appears, which emerges from the female with its tail first. The born baby immediately has the opportunity to move and develop independently, but it stays near its mother for some time. The baby whale is fed underwater, because whale milk has a high density and high fat content, as a result of which it does not spread in water. After finishing feeding, the cub almost doubles in size. The mother and the baby whale are accompanied by the male during the entire feeding period.

man hunted whales for whalebone, fat and bones. Margarine, glycerin and soap were made from fat and lard. Whalebone and bones were used for the production of corsets, figurines, jewelry, and dishes;
in the production of decorative cosmetics, spermaceti, which is found in the head of a whale, is actively used;
many species of whales are listed in the Red Book, as they were practically exterminated by whalers;
more than a dozen blue whale skeletons can be seen in various natural museums around the world;
The trainable whale is the beluga whale. It can be seen in circuses and dolphinariums. Researchers of the ocean floor trained beluga whales to search for objects lost at the bottom, deliver equipment to divers, and conduct underwater photography;
A large amount of literature has been written about various representatives of whales, while mammals act both as assistants to humans and as dangerous predators;
The names of whales, such as beluga whale or sperm whale, are used to name some types of sea or land cargo transport.

Russian fairy tales sometimes talk about the “miracle-yudo-fish-whale”. This expression, of course, can only be found in fairy tales, because a whale is not a fish at all: it breathes not with gills, but with lungs. And although he can stay under water for a long time, he still needs to rise to the surface to breathe fresh air. Whales are mammals, they give birth to live babies and feed them with milk, which is 10 times more nutritious than cow's milk. Not surprisingly, baby whales grow very quickly.

Scientists divide the entire large family of whales into two groups: baleen and toothed whales. The largest of the toothed animals is the sperm whale. It reaches 19 m in length. His favorite food is . For them, he dives to a depth of 300, 500 and even 1000 m and can stay under water for an hour or two. He has big lungs. In addition, his right nostril became overgrown and turned into a huge air sac.

Sperm whales are found in our Far Eastern seas. And in the northern ones there are other toothed whales - beluga whales. When herds of beluga whales appear off the coast, you can hear their incomparable roar. The northern seas are also home to the narwhal, also a toothed whale. True, his teeth are underdeveloped, but one of the incisors has turned into a tusk, a formidable weapon 3 m long. Narwhals and beluga whales have much in common with, and they all feed on fish.

But the killer whale is not interested in fish. These relatively small animals (5-7 m) attack seals and fur seals and tear the prey into pieces with sharp cone-shaped teeth. Killer whales dare to attack their mustachioed relatives, trying to snatch the soft, fat tongue from defenseless animals. Giants escape from killer whales by swimming in panic into river mouths and throwing themselves into shallow water.

Baleen whales include: minke whales - with longitudinal folds on the belly; gray whales - with two or three folds on the neck; right whales; bowhead whales. And finally, the largest of the Earth's animals - blue whales - up to 33 m in length and weighing 150 tons. Their baby whale, just born, reaches 5-7 m in length and drinks 100 liters of milk at one feeding.

The mouth of baleen whales is huge. It seems that anyone will be swallowed. But in fact, they have to limit themselves to small-sized prey: their esophagus is very narrow.

They would have had a bad time if not for the “mustaches,” which consist of two rows of horny plates hanging from the upper jaw. Through them, the whale filters the water, filtering out tiny crustaceans from it. A whale's stomach can hold 2-3 tons of food. A whale needs a billion crustaceans just for breakfast or lunch. In short, he has to work a lot to get enough. Whales swim in large herds. Herds of beluga whales sometimes reach several thousand heads.

Whales are very peculiar mammals, which, due to their constant life in water, are more like fish. This group of animals has a characteristic appearance and at the same time has achieved significant diversity. Whales form a separate order of Cetaceans, but this term is a collective one. Usually this word refers to large species; small cetaceans have other names (dolphins, porpoises).

Humpback whale, or humpback whale (Megaptera novaeangliae).

The most striking distinguishing feature of these animals is their size. Indeed, all species of whales are simply giants of the animal world. Even the smallest species (dwarf sperm whales, for example) reach a length of 2-3 m and a weight of 400 kg, and most species have a length of 5-12 m and a weight of several tons. The largest species, the blue whale, reaches a length of 33 m and weighs 150 tons! It is several times larger than even the largest dinosaurs. The blue whale is the largest living creature ever to inhabit our planet!

All species of whales are characterized by an elongated, streamlined body, a very short, inactive neck and a large head. The size of the head can vary greatly between species: in small whales it is 1/5 of the body length, in large baleen whales its size can reach 1/4, and in the sperm whale the head makes up 1/3 of the body. Based on the structure of their teeth, whales are divided into two suborders: baleen and toothed. Baleen whales have no teeth at all; they are replaced by giant horny plates that hang in the mouth like a fringe. They are called whalebone.

Baleen in the mouth of a whale.

Toothed whales have teeth, their shape and size vary between species. The structure of the jaws can also be different: in baleen whales the lower jaw is much larger than the upper and is similar to a ladle; in toothed whales, on the contrary, the upper jaw is larger or equal in size to the lower one. Such differences are associated with the nature of the diet of these animals.

The difference in size of the upper and lower jaws is clearly visible on the head of a humpback whale.

The brain size of whales is relatively large, but this is primarily due to the development of the parts of the brain responsible for hearing. Whales, like dolphins, have perfect echolocation abilities; they emit sounds of various frequencies and use their reflection (echo) to navigate in space, find food and communicate with each other. Just like dolphins, whales are susceptible to an unknown pathology - they can periodically wash ashore. The animals do this unconsciously (the ability of whales to commit suicide is nothing more than a stupid prejudice), but with such persistence that scientists are still puzzling over the reason for such strange behavior. Animals washed ashore are not always old or sick; moreover, sometimes, through the efforts of rescuers, they can be returned to the sea. Most likely, the root cause of such death is disruptions in the operation of the echo sounder caused by numerous radio sources (all modern navigation uses powerful sources and repeaters of radio waves). Such electromagnetic “noise” in the ocean confuses the giants and they approach the shores; moreover, accustomed to trusting their feelings, the whales stubbornly strive in the “right” direction until they run aground. Other sense organs in whales are poorly developed: the sense of smell is in its infancy, and vision is also rather weak.

On the top of the head there is a breathing hole - a blowhole. In more primitive baleen whales it consists of two openings (“nostrils”), in toothed whales there is only one opening. Interestingly, during exhalation, moist air from the lungs creates a kind of fountain, and its shape depends on the type of whale.

A blowhole with two nostrils on the head of a gray whale (Eschrichtius robustus).

The limbs of whales are arranged in a very unusual way. The front ones have turned into flattened fins, and their size can vary greatly among different species. For example, the fins of belted teeth and sperm whales are small, and they reach their greatest development in the humpback whale.

The long fins of a humpback whale resemble wings underwater.

But whales have no hind limbs at all; in their place in the lumbar spine there are only two small bones to which the muscles of... the genital organs are attached. The driving force in the whale's body is created by a powerful twin tail, but these are not modified hind legs, as some believe.

The powerful tail is used by whales for movement and protection.

The coloration of whales is varied, but discreet. More often, their body has a dark upper side and a lighter lower side; some species (Bryde's minke) may have clearly visible stripes on the underside of the head. Species such as the blue whale, gray whale, and sperm whale are uniformly gray or brown in color.

The beluga whale (Delphinapterus leucas) gets its name from its rare white skin color.

Whales are widespread throughout all oceans (and some seas) of the globe. They are found only in deep waters; as a rule, they do not enter bays, river mouths and similar shallow waters. Whales usually move freely across the ocean, but their movement is not chaotic. Each whale species has favorite breeding grounds that they visit during certain seasons. The rest of the time, whales fatten up, but do this in areas remote from their breeding grounds. Thus, whales migrate with a cyclicity of 1 year. When feeding, whales swim at a speed of 10-20 km/h, but in case of danger they switch to a cruising speed of 50 km/h. Adult males and non-breeding females stay alone, females with cubs, as well as all animals during the breeding season form herds of 5-15 individuals. There is a peaceful atmosphere inside the herd: the whales have no internal hierarchy, they do not show aggression towards each other, in case of danger, all members of the herd try to defend themselves with common efforts, there are even cases of mutual assistance to wounded brothers. In general, whales, with their huge size and clumsiness, give the impression of stupid and uninteresting animals. But this is a false idea! These peculiar animals are endowed with developed intelligence and are not inferior to dolphins in intelligence. For example, there are cases when whales showed interest in the underwater photographers who were filming them - the animals approached people and even tried to play with them in their own way, pushing them to the surface. Another example: whalers tracked down a female whale with her calf and killed the latter. The whale carcass was transported to the cutting site in tow. All this time, the female swam nearby and tried to remove the corpse of the cub from the rope. Captive whales in captivity quickly get used to people and are able to perform tricks (to the best of their physical capabilities). Like all highly developed animals, whales love to play, while they jump high out of the water and beat their tails loudly.

Minke whale (Balaenoptera acutorostrata).

Whales feed on a variety of marine animals, and there is a narrow specialization in the nutrition of different species. Baleen whales eat exclusively plankton - the smallest sea crustaceans. They extract it by filtering large volumes of water. To do this, the whale opens its mouth and takes water into its mouth...

Humpback whales use their open mouths as a scoop.

then with his tongue, like a piston, he pushes the water out of his mouth - the water flows freely through the whalebone, but the crustaceans remain.

A whale strains water with plankton.

Toothed whales feed on fish, which they also catch not individually, but in whole schools. Sperm whales specialize in catching deep-sea fish and shellfish (mainly squid). Many whales make long dives for hunting; they can stay under water for up to 1.5 hours. The record holders for diving depth are sperm whales, which were encountered at a depth of 1 km!

Whales are very infertile animals. Females reach sexual maturity at 7-15 years, males only at 15-25. Moreover, each individual participates in reproduction no more than once every 2 years. In the mating ritual of whales there is not only no aggression, but also any kind of struggle at all. Male whales attract the attention of females with their songs! Whale voices are surprisingly delicate for animals of their size. Each species of whale has its own set of sounds, but even individuals of the same species differ in the tone of their voice. The whale's song resembles a melodic moan and sounds very loud. According to divers, when a whale sings, the water around it vibrates. Female whales can mate with several males, since there is no struggle between representatives of the stronger sex, selection occurs in a very unusual way. It turns out that the gonads of whales are enormous (in the sperm whale, for example, up to 10-20% of body weight) and are capable of producing large amounts of sperm. Thus, among several males mating with one female, the one whose hormonal status is higher wins. Pregnancy in various species lasts 11-18 months. The female gives birth to only one calf, but it is large and developed. For example, the weight of a newborn blue whale is 2-3 tons. The calf is born tail first and, with the help of its mother, rises to the surface for its first breath. The mother often feeds the cub with very rich milk, due to which it grows quickly. The lactation period of whales is relatively short - 5-7 months. During this time, the cub manages to grow 2 times, then its growth slows down sharply. For another 1.5-2 years, the cub accompanies the mother, using her protection. In small and medium-sized whales, young animals are kept in herds until they reach sexual maturity, and sometimes later. Whales live 50-70 years.

Baby blue whale (Balaenoptera musculus).

It would seem that nothing could threaten such gigantic animals in this world. In reality, whales are very vulnerable to various dangers. In the ocean, whales have no enemies except... their own brothers. Killer whales (giant predatory dolphins often called whales) attack other species of cetaceans. Killer whales live in groups and act collectively, so even adult whales can hardly resist their coordinated attack, and the calves are completely defenseless. When attacked, whales try to escape by “flight”, swimming away from the herd of killer whales at high speed. If it was not possible to break away from the pursuit, the whale tries to fight off the attackers with strong blows of its tail, the mother swims under the calf from below, trying to cover it with her body.

But even in the absence of predators, whales have enough problems. Sometimes these animals experience... hunger. Massive fishing, global warming, and changing sea currents undermine the food supply of whales and animals can drift for several weeks in “barren” waters. Researchers have encountered extremely emaciated animals. In the Arctic Ocean, whales often become trapped in ice. Since whales breathe air, they are forced to surface regularly to replenish their supplies. If there are no suitable polynyas around, whales break through the ice with their heads, but they do not always succeed. When the ice is thick (or the opening is small), entire herds of whales suffocate under the ice.

Minke whale in Antarctic ice.

To top it all off, whales are actively hunted by people. Despite their impressive size (or rather, because of them), whales are attractive prey for fishing. There are no useless parts in a whale carcass; everything is used: fat (blub), meat, baleen, teeth, skin. Sperm whales are suppliers of very exotic products - spermaceti and ambergris. Spermaceti, despite its name, is not whale sperm at all, but a fat-like substance from the brain. Ambergris is found in the intestines and has a pleasant smell, which is why it got its name. Both substances are very valuable raw materials in the cosmetics industry and are extremely highly valued on the world market.

As a result of the impact of unfavorable factors, the number of almost all species of whales has greatly decreased, many species are on the verge of extinction. In this regard, the World Convention on the Prohibition of Whale Fishing was adopted (especially since whaling products have lost their relevance in our time). The only country that has not signed the convention is Japan. Japanese whalers still carry out mass fishing of all whales indiscriminately, justifying themselves by the fact that whale meat... is a traditional component of Japanese cuisine. On the other hand, tourism in whale breeding grounds has gained wide popularity. Nature lovers visit such places on small boats; queues line up to tour operators for the opportunity to watch whales live and hear their songs. Attempts to keep whales in captivity run into many obstacles: large species of whales cannot be kept due to their size, baleen whales cannot be fed with plankton, and catching an adult whale without killing it is very difficult. Repeated attempts to catch the cubs led to the death of the babies even at the transportation stage. Only the smallest species of whales (beluga whales, pilot whales) take root in aquariums, but they do not breed there. Perhaps the only way to preserve these unique animals is a widespread ban on their hunting and comprehensive protection of water resources.

The carcass of a beached blue whale is being cut up for further scientific research.

Whales (in Greek - “sea monsters”) are large marine mammals belonging to the fairly large order Cetaceans. The status of the name has not been fully determined at the moment, but representatives of Otrad include any cetaceans, with the exception of dolphins and porpoises.

Description of whales

Along with other mammals, whales use lungs for breathing, belong to the category of warm-blooded animals, feed their newborn offspring with milk produced by the mammary glands, and also have fairly reduced hair.

Appearance

Whales have a spindle-shaped body that resembles the streamlined shape of almost any fish.. The fins, which are sometimes called flippers, have a lobe-like appearance. The tail end is characterized by the presence of a fin, represented by two horizontal blades. Such a fin has the function of a stabilizer and a kind of “engine”, therefore, in the process of wave-like movements in the vertical plane, the whales are provided with fairly easy movement in the forward direction.

This is interesting! Whales, like dolphins, do not need to rise to the surface of the water very often for the purpose of breathing, so only half of the animal’s brain is able to rest during sleep at a certain time.

The protection of the whale's skin from the negative effects of ultraviolet sunlight is provided by various protective devices, which differ markedly in different groups of cetacean mammals.

For example, blue whales are able to increase the content of pigments in their skin, which very effectively absorb a fairly large amount of ultraviolet radiation. Sperm whales trigger special “stress” reactions, similar to the response to exposure to oxygen radicals, and fin whales are able to use both protective methods. In cold waters, whales maintain a stable body temperature thanks to a very thick and uniform fat layer located directly under the skin of such a large mammal. This layer of subcutaneous fat serves as a very effective and complete protection of the whale’s internal organs from severe hypothermia.

Character and lifestyle

According to scientists, whales belong to the category of animals that lead a predominantly diurnal lifestyle. Almost all representatives of the order Cetaceans are capable of staying directly under water for a long time and without renewing air in their lungs, but a significant number of such mammals rarely use this natural opportunity, so whales most often dive only when immediate danger appears.

However, among whales there are real, very good deep-sea swimmers. For example, the sperm whale is such an unsurpassed diver. This whale can easily dive into water to a depth of a couple of thousand meters, remaining underwater for an hour and a half. This feature is due to the presence of several changes that the whale’s body has undergone, including increased lung capacity and increased hemoglobin content in the blood, as well as a high volume of myoglobin in muscle tissue. In addition, the whale's respiratory center has low sensitivity to the amount of carbon dioxide. Before diving, the whale breathes very deeply, during which the muscle hemoglobin is actively saturated with oxygen and the lungs are filled with clean air.

This is interesting! All whales are gregarious marine animals, preferring to form groups of several dozen or even hundreds of individuals.

Whales are large animals, but very peaceful. Many cetacean species are characterized by seasonal migrations. With the onset of cold weather, mammals migrate towards warmer waters, and after a while return back. From year to year, such aquatic animals adhere to only one route, so during the migration process they return to already inhabited and familiar areas. For example, the Asian herd of fin whales is characterized by summer fattening in the Sea of Okhotsk, rich in food, near the Chukotka Peninsula and Kamchatka. With the onset of cold weather, such whales move to the waters of the Yellow Sea or closer to the southern Japanese shores.

How long do whales live?

The smallest species of whales live about a quarter of a century, and the average life expectancy of the largest representatives of the order Cetaceans can be fifty years. The age of a whale is determined in several ways: according to the appearance of the female's ovaries or baleen plates, as well as by the ear plug or teeth.

Types of whales

Representatives of the order Cetaceans are represented by two suborders:

Baleen whales (Mysticeti) – are distinguished by the presence of whiskers, as well as a filter-like structure, which is located on the upper jaw of the animal and consists mainly of keratin. Baleen is used in the filtration of various aquatic plankton and allows a significant volume of water to be filtered through the comb-like mouth structure. Baleen whales are by far the largest representatives of all suborders of whales;
Toothed whales (Odontoseti) – are characterized by the presence of teeth, and the structural features of such aquatic mammals allow them to hunt squid and fairly large fish, which are the main source of their diet. The special abilities of absolutely all representatives of this group also include the ability to sense the features of the environment, called echolocation. Toothed whales also include porpoises and dolphins.

The group Baleen whales is divided into four families: minke whales (Balaenopteridae), gray whales (Eschrichtiidae), smooth whales (Balaenidae) and dwarf whales (Neobalaenidae). Such families include ten species, represented by the bowhead, southern pygmy, gray, humpback, blue, fin and sei whales, as well as minke and Bryde's whales.

The families of toothed whales include:

Gangetic dolphins (Platanistidae Gray);
Dolphinidae (Delphinidae Gray);
Narwhals (Monodontidae Gray);
Sperm whales (Physeteridae Gray);
Inii (Iniidae Gray);
Dwarf sperm whales (Cogiidae Gill);
Beaked whales (Ziрhiidae Gray);
Laplatan dolphins (Pontororiidae Gray);
Porpoises (Phocoenidae Gray);
River dolphins (Lipōtidae Gray).

The third suborder of the order Cetaceans are the ancient whales (Archaeoceti), which are today a completely extinct group.

Range, habitats

The largest distribution area is distinguished by sperm whales, which live in the waters of the entire World Ocean, with the exception of the coldest southern and northern regions, and dwarf sperm whales also inhabit warm or moderately warm waters of the World Ocean.

Representatives of baleen whales are widespread in the oceans, with the exception of the bowhead whale, which lives in Arctic waters, the Bryde's whale, which inhabits the warm zone of the World Ocean, and the dwarf whale, which is found in the cold and temperate waters of the Southern Hemisphere.

Whale diet

The composition of the diet of different cetacean species varies in accordance with their geographical distribution, ecological zone and time of year. Depending on their basic food preferences, different species of whales live in certain oceanic zones. Planktivores or smooth whales feed mainly in the waters of the open sea, catching accumulations of zooplankton in the surface layers, represented by small crustaceans and pteropods. Benthophages or gray whales typically feed at shallow depths, and ichthyophages from the dolphin family prefer to catch schooling fish.

A significant part of minke whales are accustomed to a mixed diet represented by various crustaceans and fish, and teutophages, including sperm whales, beaked whales and gray dolphins, prefer only cephalopods.

Seasonal changes in feeding conditions can cause quite sharp fluctuations in such a parameter as the level of fatness of whales. Cetaceans are the most well-fed at the end of the autumn feeding period, and mammals become less well-fed in spring and winter. During the active breeding season, many whales do not feed at all.

Reproduction and offspring

All species of whales are adapted to produce their offspring exclusively in fairly warm waters. It is for this reason that mammals that live in cold areas and are accustomed to making long migrations give birth to their babies in the winter, moving to areas with higher water temperatures.

This is interesting! Newborn whales are not only very large, but also well formed, which is due to the loss of pelvic bones in such aquatic animals, which impose some restrictions on the maximum size of the fetus.

Pregnancy in various species of whales lasts from nine to sixteen months, and the result of childbirth is the birth of one whale, which is born tail first. A newborn baby, immediately after birth, rises to the water surface, where he takes his very first breath. The whales very quickly adapt to the new environment and begin to swim well and quite confidently. At first, the cubs stay close to their mother, which not only makes their movement easier, but also makes it as safe as possible.

The whales feed very often and attach themselves to the mother's nipple almost every quarter of an hour.. After sucking on the nipple, thanks to the contraction of special muscles, warm milk is independently injected into the baby’s mouth. Depending on the characteristics characteristic of the subspecies or species, different cetaceans produce different volumes of milk, which varies from 200-1200 ml in dolphins and up to 180-200 liters in a large blue whale.

Cetacean milk is very thick, creamy in color, and about ten times more nutritious than traditional cow's milk. Due to the high surface tension, whale milk does not spread in water, and the lactation period can last from four months to a year and sometimes partially coincides with the female’s next pregnancy.

Whales are characterized by a highly developed parental instinct, which is why such large aquatic mammals never leave their young in danger. Even if a whale calf finds itself in shallow water at low tide and is not able to swim away on its own, its mother will definitely wait for the tide and take her baby to the safest, most comfortable place. Adult whales are able to bravely rush to the aid of harpooned calves, and try to drag their calves away from the ship. It was precisely this boundless devotion of adult whales that whalers very often took advantage of, luring large individuals to the ship.

This is interesting! Beluga whales are trainable whales that often perform in dolphinariums and circuses, so calves of this species are especially highly prized.

It is well known that whales are distinguished by a surprisingly touching attitude not only towards their calves, but also to any relatives. All representatives of the order Cetaceans almost never abandon their sick or wounded brothers in trouble, so they try to come to the rescue in any case.

If a whale is too weak and is not able to rise to the surface on its own to breathe air into its lungs, then several healthy individuals surround such an animal to help it float, after which they carefully support the relative afloat.