Whale shark (rhincodon typus). Whale shark: what it looks like and where does the largest fish live

The whale shark is the largest known existing fish on the planet. The whale shark is enormous in weight and size, and is a very rare specimen of fish, which is under the protection of an animal protection organization. The fish is very sedentary, slow and does not pose a danger to humans.

Description of the whale shark

It is simply not possible to confuse this view, because it has a huge size and special appearance... The shark has a thick and powerful body with a flattened head, which is small in size. Closer to the snout, it becomes almost flat. The mouth is at the end of the snout and not under it, and on the body there are 5 gill slits, which are about 1.5 meters wide, by the way, the mouth is about the same size. The eyes are very small and are very close to the mouth, and this does not explain very much good vision sharks. So you understand, her eyes are about 5 centimeters, which separate the dark side of the back and the white belly of the shark. The size of a shark can reach up to 18 meters, and the largest recorded specimen reached a length of 16.65 m. This species of shark can have up to 15 thousand teeth that look very small. Even the largest specimen has teeth no more than 6 millimeters in size.

This type of shark lives, as a rule, in warm waters low latitudes. They prefer waters where the surface water temperature is at least 20 ° C and the salinity of the water is about 33 ppm. There is evidence that has been observed whale sharks v fresh waters river mouths. This may be due to the fact that plankton are collected there in large quantities, which constitute the main diet of the shark. Mass concentrations of this shark species can be observed in June - August, October - November in the area seychelles near Taiwan. Same way permanent places whale shark sightings are southern and southeastern Africa, the Gulf of Mexico, the coast of Chile, Australia and Mozambique.

Lifestyle, nutrition and reproduction

The shark itself is inactive and clumsy. Most of its time, it sits near the surface of the water and moves very slowly through the water. The approximate speed of this fish is 5 kilometers per hour. This species of shark, unlike others, accepts exclusively plankton for food, and does not pose any danger to humans. The way a shark feeds is very similar to whales, which is why it got its name. The shark takes food, which it receives along with water, through a filter apparatus, which consists of 20 cartilaginous plates. This apparatus is located on the top of the palate. After that, the strained feed enters the stomach through the esophagus, and the water is released into the sea. At the same time, you should know that the whale shark can feed on everything that its one and a half meter mouth can swallow. Very little is known about the reproduction of this species of fish, since it is very difficult to reliably study this component of fish life. The main data comes from a study of captured pregnant samples in 1995. From which it became known that these sharks are ovoviviparous and the sample caught had 307 embryos, ranging in length from 40 to 60 centimeters. Sharks are known to migrate over fairly long distances. For example, a shark that was tagged in northern Australia migrated 1,800 kilometers in 35 days.

The first time zoologists encountered this species was in 1828. This 4.5 meter specimen was caught in South Africa. Well-known naturalist Andrew Smith was engaged in its research. A stuffed fish of this fish was sent to Paris, where it remains to this day. An interesting fact is that in 1911 a steamer en route from England to India dragged a 17-meter whale shark on its bow for about 15 minutes. Since the shark almost does not react to divers in any way, people involved in the tourist business take advantage of this. This type of tourist destination is especially common in the USA, Canada and Australia.

Whale shark, belongs to the class cartilaginous fish because her skeleton is made of cartilage, not bone.

Whale sharks live in temperate and tropical waters. Representatives of this species swim to Florida and California. These sharks are not found near Japan. In the south, these giants do not swim farther than Brazil and Northern Australia. The whale shark is not found in the Mediterranean Sea, but it does live in the vastness of the Indian Ocean. Some individuals swim to Africa.

In terms of body structure, the whale shark corresponds to other shark species. But the whale shark, unlike other members of the family, does not have large teeth with which sharks pull out pieces of meat from the victim. How do whale sharks feed?

The appearance of a whale shark

Whale sharks are considered the largest fish species. The average body length is 9.7 meters, and individuals weigh about 9 tons.

In 1947, a whale shark measuring 12.6 meters, which weighed 22 tons, was caught off the coast of Pakistan.

There are many rumors about the huge size of this species. It is believed that the body length of these giants can reach 21 meters, and their body weight can be 35 tons, but actual evidence has not yet been provided. Most likely, all this talk is just a consequence of the rich human imagination.

The whale shark has a thick skin covered with placoid scales. The skin on the back is thicker than on the belly. The shark's head is flat with small eyes. The body is grayish brown on top, and the belly is dirty white. The body is decorated with patterns of pale yellow stripes and spots, and each individual has an individual pattern that does not change throughout its life.

This fish has 2 dorsal and pectoral fins. The tail is divided into 2 lobes, the upper part is larger than the lower one. Such a tail is inherent in young sharks. And in mature individuals, the tail has the shape of a crescent.

Whale shark lifestyle and nutrition

Although these fish have large mouths, they are not interested in large animals. The width of the mouth of a whale shark reaches 1.5 meters. There are 300-350 tiny teeth in the mouth. There are 5 branchial slits on each side of the body. These slots are very essential during meals. The whale shark sucks water into its huge mouth along with krill, plankton, small fish and crab larvae. When the shark closes its mouth, the teeth do not allow the living creatures to slip out.

Water comes out of the mouth through the gill slits. The gills have special flaps, in the form of a sieve. Anything more than 2 millimeters in size comes out through such a sieve. The shark swallows this living creature. The smallest living creatures clog the flaps, in order to clean them, the fish “coughs”. During a cough, all the small things fly out of the mouth and thus the flaps are cleaned.

Whale sharks swim slowly average speed is 5 kilometers per hour. These fish dive to a depth of 700 meters.

Whale shark breeding

Whale sharks are ovoviviparous, that is, during childbirth, babies hatch from eggs. The number of cubs can be up to three hundred. Babies are 40-60 centimeters in size. After birth, sharks may not eat anything for 2 weeks.

Whale sharks reach sexual maturity at the age of 30. It is believed that there are fewer females than males. But this information has not been verified. Dimensions of females more males, besides, they come earlier puberty.

These huge fish live quite a long time - from 70 to 90 years.

Commercial value and protection from enemies

Whale sharks are fished. These giants are caught for their liver and meat, which is rich in shark fat. Today, this shark species is considered vulnerable as the population is steadily declining. Fishermen try to catch larger representatives of the species, and they, as a rule, are females. It is quite easy to catch a whale shark, as it, due to its calm nature, does not offer resistance.

Although the whale shark bears the title greatest fish on the planet, it still remains practically harmless to humans. She has no natural enemies, but is constantly on the move, absorbing small fish and other "living dust".

Description of whale shark

The whale shark was noticed by ichthyologists relatively recently.... It is described for the first time in 1928. Its enormous outlines were often noticed by ordinary fishermen, from where fables about a huge monster living in the sea surface spread. Various eyewitnesses described her in a terrifying and unsightly form, not even knowing about her harmlessness, apathy and good nature.

This type of shark is striking in its large size. The length of the whale shark can reach up to 20 meters, and the record weight reaches 34 tons. This is the largest sample that was captured at the end of the last century. The average size of a whale shark ranges from 11-12 meters, with a weight of about 12-13.5 tons.

Appearance

Despite such an impressive size, it was the structure of her mouth that influenced the choice of the name, and not the size. The point is the location of the mouth and the peculiarities of its functioning. The mouth of a whale shark is located clearly in the middle of a wide muzzle, and not below, like many other shark species. She is very different from her fellows. Therefore, a special family has been allocated for the whale shark with its own class, consisting of one species, his name is Rhincodon typus.

Despite such an impressive body size, the animal can hardly boast of the same powerful and large teeth. The teeth are very small, reaching no more than 0.6 mm in length. They are located in 300-350 rows. In total, she has about 15,000 small teeth. They restrain small food in the mouth, which later enters the filter apparatus, which consists of 20 cartilaginous plates.

Important! This species has 5 pairs of gills and relatively small eyes. In an adult, their size does not exceed a tennis ball. Interesting fact: the structure of the visual organs does not imply the presence of an eyelid as such. During an approaching danger, to preserve its vision, the shark can hide the eye by pulling it inside the head and covering it with a skin fold.

The body of the whale shark thickens in the direction from the head to the base of the back, forming a raised area in the form of a gentle hump. After this section, the circumference of the body goes down to the tail itself. The shark has only 2 dorsal fins, which are displaced back towards the tail. The one that is closer to the base of the body looks like a large isosceles triangle and is larger in size, the second one is smaller and is located a little further towards the tail. The tail fin has a typical sharply asymmetrical appearance, characteristic of all sharks, with the upper blade elongated one and a half times.

They are gray in color with bluish and brownish blotches. The belly of a shark is cream or whitish in color. On the body, you can see stripes and spots of a light yellowish color. Most often they are located in a prim correct order, stripes alternate with spots. The pectoral fins and the head also have spots, but they are more chaotically located. There are more of them, but they are smaller. At the same time, the pattern on the skin of each shark remains individual and does not change with age, which has a beneficial effect on tracking their population.

Interestingly enough, in the very process of tracking, ichthyologists are assisted by equipment for astronomical research. There are special devices whose task is to compare and compare images of the starry sky, this helps to notice even minor differences in the location of celestial bodies. They also effectively cope with the location of spots on the body of a whale shark, unmistakably differentiating one individual from another.

The sides, to improve the hydrodynamic properties, are covered with poorly developed scales. On the belly, the skin of a whale shark is one third thinner than the main layer. That is why, during the approach of curious divers, the animal turns its back to it, that is, the most naturally protected part of its body. In terms of density, the scales themselves can be compared with the teeth of a shark, which is provided by a special coating of an enamel-like substance - vitrodentin. This placoid armor is common to all shark species.

Dimensions of a whale shark

The average whale shark grows up to 12 meters in length, reaching a weight of about 18-19 tons. In order to visualize it visually, these are the dimensions of a full-size school bus... Just one mouth can be up to 1.5 meters in diameter. The largest specimen caught had a girth of 7 meters.

Lifestyle, behavior

The whale shark is a slow animal with a calm, peaceful disposition. They are "sea tramps" and little is known about their life. For most of their lives, they swim unnoticed, occasionally appearing off the coral reefs. Most often, the depth of their immersion does not exceed 72 meters, they prefer to stay closer to the surface. This fish is not very maneuverable; it cannot sharply slow down or stop due to the absence of a swim bladder and other structural features of the body that provide oxygen supply. As a result, he often gets injured, bumping into passing ships.

It is interesting! But at the same time, their capabilities go far ahead. The whale shark is able to stay at a depth of about 700 meters, like most other shark species.

While swimming, the species of whale sharks, unlike others, uses not only the tail part for movement, but two-thirds of its body. The acute need for a regular intake of food makes them more likely to stay close to schools of small fish, for example, mackerel. They spend almost all their time in search of food, coming off only for short periods of sleep, regardless of the time of day. They drift most often in small groups of several heads. Only occasionally can you see a large flock of 100 heads or a shark traveling alone.

In 2009, a cluster of 420 whale sharks were observed off the coral reefs, so far this is the only reliable fact. Apparently, the whole point is that in August there is a lot of freshly swept mackerel caviar off the coast of Yucatan.

For several months every year, hundreds of sharks begin circling the coast of Western Australia near the largest reef system that borders it, Ningaloo. Almost all creatures, from small to large, come for profit and reproduction off the coast of Ningaloo during the period when the reef is in full swing.

Life span

Experts differ on the issue of reaching sexual maturity for whale sharks. Some believe that individuals that have reached 8 meters in length can be considered sexually mature, others - 4.5 meters. It is assumed that the animal at this moment reaches the age of 31-52 years. Information about individuals that have lived for more than 150 years - pure water myth. But 100 is a real indicator of shark centenarians. The average figure is around 70 years.

Habitat, habitats

To represent the habitat, it is important to understand that whale sharks live in areas where food is concentrated for survival. They are also thermophilic animals, preferably choosing an area with water heated to 21-25 ° C.

Important! You will not meet them north or south of the 40th parallel, often living along the equator. This species is found in the waters of the Pacific, Indian and Atlantic oceans.

Whale sharks are mostly pelagic fish, which means they live on the high seas, but not in great depths ocean. The whale shark is commonly found in coastal waters South Africa, Central America and South America... It is often sighted close to the shore while feeding off the reef shores.

Whale shark diet

One of the most important aspects The feeding of whale sharks is their role as filter feeders. Teeth don't play big role in the process of feeding, they are too small and participate only in the process of keeping food in the mouth. Whale sharks feed on small fish, mainly mackerel, as well as small plankton. The whale shark plows the ocean, sucking a large number of water together with small nutritious living creatures that come across. This feeding pattern is inherent in two more species - giant and meter pelagic bigmouth sharks... However, each feeding process has its own fundamental differences.

The whale shark powerfully sucks in water, then the food enters through filter pads that cover the mouth entrance. These filter pads are full of millimeter wide pores that act like a sieve, allowing water to pass through the gills back into the ocean as it picks up the right food particles.

Whale shark(Rhincodon typus) - the most big fish from those who now live in the vastness of the world's oceans. The size of her giant body can amaze anyone who has not previously met this representative of the ocean fauna.

The weight of a whale shark reaches 12 tons, although there are scientists who claim that the most large specimens can weigh more than 20 tons. With such a body weight, the length of a whale shark is corresponding - on average, 11-12 meters.

Representatives of this species live in the warm waters of the world ocean, therefore for a long time about the whale shark was known only from the stories of sailors who roamed the vastness of the tropical seas.
Since people tend to exaggerate, the information of the sailors about giant fish may well have contributed to the emergence of legends about sea monsters.

For the first time, zoologists were able to study this fish in detail in 1828 off the coast of South Africa. Then for the first time a shark with a length of 4.5 meters was harpooned. These thermophilic creatures are most often found off the Philippine Islands, off the coast of Southern California, and in the waters of Cuba. Mostly the great whale shark lives in upper layers ocean waters (scientists call such fish pelagic, that is, living near the surface).

The whale shark has a powerful and heavy body, with a relatively small head and huge gill slits, five in number on each side. The torso is usually dark gray or Brown color, and is covered with numerous spots of a white or yellowish tint, which in places line up in regular stripes.

There is practically no information about the reproduction of the whale shark. It was known that it reproduces by laying eggs, but only recently it was found out that sharks hatch while still in the womb of the female, and then continue their development in an airtight "capsule". These capsules are extremely rare, and in fact the only specimen found is a shark egg caught in the Gulf of Mexico. Its dimensions were unusually large - almost 70 cm in length and 40 cm in diameter.

An uninformed person can easily rank the whale shark as a source. increased danger... However, despite its formidable appearance and very large dimensions, this fish does not carry any danger for humans, and for other creatures. It feeds exclusively on small oceanic animals - plankton, crustaceans and small schooling fish.
To catch prey, the fish opens its mouth wide (which reaches one and a half meters in diameter and is shown in the photo above) and sucks into itself sea ​​water together with plankton.

Possessing solid dimensions, natural enemies in nature, the whale shark does not. She swims in the water column at a speed of no more than 5 km / h, not paying attention to what is happening around, thanks to which scuba divers like to take pictures with her. In the video, you can see how this ocean giant behaves in natural environment a habitat.

Whale shark (lat.Rhincodon typus)- most large view sharks, as well as the largest living fish. Although, according to some eyewitnesses, they met specimens ranging in length from 18 to 20 m, the largest specimen ever measured was 13.7 m long.Whale sharks can weigh up to 12 tons. Despite its impressive size, a whale shark is absolutely safe, as it eats like giant shark and the bigmouth shark exclusively by plankton and other small organisms, which it filters, drawing in water.

The whale shark is the only species in the genus Rhincodon, which in turn is the only one in the family of whale sharks (Rhincodontidae). Whale sharks belong to the Wobbegong-like order.

External signs
Whale sharks are gray, brown, or bluish in color, with a lighter belly and light-colored stripes and spots on the back. Whale sharks have two dorsal fins, as well as pectoral and anal fins and five gill slits. The large mouth extends over the entire width of the flattened and obtuse front of the head. Due to their size and unusual coloration, whale sharks cannot be confused with other fish.

Whale sharks prefer water temperatures between 21 and 25 ° C and are common throughout the world, found in almost all warm tropical and subtropical seas. They are especially abundant in regions with a high seasonal plankton content.

Behavior
Whale sharks actively suck in water (up to 6000 l / h), passing it through their gills equipped with a comb-like filtration apparatus. It consists of cartilaginous plates connecting the individual gill arches to each other like a lattice, and on which dermal teeth are located. In order to cover the huge needs for food, whale sharks filter from the water, in addition to plankton, small fish, as well as other small inhabitants of the seas.

Until April 1828, when several brave African Fishermen managed to harpoon this huge fish, the whale shark was a ghost that was occasionally seen, about which all sorts of fables were often told, but which had never been caught and studied. Many years have passed since then, quite a lot of whale sharks have been caught and a lot has been learned about them, but they still do not cease to amaze us with their size. Their length reaches 20 meters.

In 1912, a whale shark weighing 13.5 tons was caught off Nants Key in Florida. Their dimensions are so large that it is almost impossible to accurately determine their weight. Dr. E. W. Gajer, who has devoted his entire life to the study of whale sharks, believes that 12 meters is only average length these huge sharks, and that some of them reach a length of 23-25 ​​meters. The weight of such a shark, calculated according to the formula proposed by Dr. Gajer, should be at least 20-25 TONS. In the logs of ships of all countries, there are cases of collisions between a whale shark and a ship. Here is a typical recording made by the captain of a schooner after such a collision near Cape San Lucas, off the southern tip of California: “A huge shark appeared on the starboard side and hit the vessel with such force that the helmsman let go of the steering wheel. The shark's tail rose 2.5 meters above the ship's bulwark and more than 4 meters above sea level. The order was given to turn off the engine, as the fish broke the propeller. When the fish backed up, we were able to properly examine it: it had a speckled color and it reached at least 9-10.5 meters in length. When, upon arrival at the port, the ship was put into dry dock, it turned out that the hull and rudder had been seriously damaged. ”

Judging by the numerous evidences, whale sharks are purely accidentally in the path of the ship and certainly have no intention of attacking it. Perhaps they are driven by curiosity that is fatal to them, and sometimes to the ship. If whale sharks attacked the ship, and did not expose themselves to its blow, we would never read one of best books written about the sea: "KON-TIKI" Thura Heyerdahl. The author tells how one day, when he climbed onto the raft after swimming, there was a shout: "Shark!" Directly behind the stern, a fish swam "with the largest and ugliest mug" that the people on the raft had ever seen. Heyerdahl says she was so scary that “rise from the bottom of the sea yourself sea ​​Devil, he couldn't have scared us more. " But the Kon-Tiki scientists had nothing to fear. Whale sharks are so apathetic that people literally rather than figuratively walked their backs.

Here is what an employee of the Scripps Oceanographic Institute, who once came across a whale shark with a group of scuba divers: “We climbed the shark and examined it properly, even looked into its mouth. She didn't seem to notice us at all. Only when we began to touch her snout, she slowly went to the depth. But soon I went upstairs again, and we climbed on it again. " There are many stories about the lethargy and lethargy of whale sharks. However, one should not forget that fish of such gigantic sizes can be dangerous by their size alone. When a ten-meter whale shark accidentally hit the net near Fire Islene New York, it took three hours to subdue it. Trying to free herself, she can easily kill a person, and even two, with a blow of her powerful tail. True, not a single such case has been registered so far.

The whale shark feeds on crustaceans and small fish, which it draws along with the water into its huge mouth, where, slightly bent over, an adult can fit. The whale shark has a huge number of tiny teeth (scientists took the trouble to count them in one specimen - there were 15 THOUSANDS of them). All these teeth with a narrow band girdle the mouth just behind the mouth of the shark. They can neither bite nor crush food, and their only purpose is to keep in the mouth what gets into it along with water. When the whale shark is in motion, it draws in water with its mouth and then releases it through the gill slits. Passing the gill slits, the water is filtered through a thick gill "sieve" consisting of closely spaced cartilaginous septa connecting the gill arches. Thus, the small crustaceans of the fish, which have fallen into its mouth with the current of water, find themselves in a trap, the only way from which is into the throat of the shark.

The whale shark's throat is very narrow, and the esophagus turns to the stomach almost at right angles. It is clear that she cannot swallow big fish, and even more so a person who happened to be on her way. In the stomach of one huge shark, presumably a whale, 47 buttons, 3 leather belts, 7 gaiters and 9 shoes were found. This find caused the most different interpretations... Some said that this shark was not at all a whale shark, others that it was a whale shark that had swallowed stocks of haberdashery that accidentally found itself in the sea, and even that the objects found in its stomach were the only traces of people it had swallowed.

We know almost nothing about how the whale shark reproduces, although it has been observed for over a hundred years. There are only a few scattered facts that help to unravel this riddle. In 1910, 16 egg capsules were found in the oviducts of a female whale shark anatomized in Ceylon. In 1955, a similar capsule was discovered two hundred kilometers from Port Isabel in Texas at a depth of fifty-seven meters. It contained a whale shark embryo, easily identified due to its characteristic color - white spots and stripes on a dark background. The egg was 63 centimeters long and 40 centimeters wide.

There was no longer any doubt that whale sharks produced their offspring with the help of eggs. The whale shark is a pelagic fish. It is found in tropical zones Atlantic, Pacific and Indian oceans... But it comes across to the north, at the latitude of New York and even Massachusetts.