Fish and other aquatic creatures

White-faced dolphin

Dear guys, hello. And you, dear parents, I welcome on the pages of the informative blog “SchoolLa”. We continue to help learn. Today we are preparing a report on the theme “The White Sea Dolphin from the Red Book of Russia”.

I think all of you have met these amazing creations of nature. Someone watched performances in dolphinariums, and some even swam with dolphins. Usually they are all gray, but there are rare unique species, such as the one about which we are going to talk.

What do we know about dolphins?

Dolphins are a suborder of toothed whales, mammals that have teeth on their jaws.

In Greek, the word dolphin means brother. And in fact, our younger brothers are always in a hurry to help not only their relatives. They have repeatedly saved drowning people and defended against aggressive sharks.

Science has long noted the high mental development of these mammals. Probably, many have seen how dolphins escort ships, as if they are guarded from danger. At the same time they make shrill sounds.

It is interesting! Research scientists say that dolphins "vocabulary" consists of almost 14,000 sounds, with the help of which they communicate with each other.

These are animals that are not very fond of loneliness, so they live in families - often in small flocks of 6 to 8 individuals.

But sometimes such groups come together in a thousand sea representatives, especially in places where there is a lot of food. It happens that a single pair of dolphins is not separated throughout his life.

In the natural environment, dolphins live up to 40-45 years, but in conditions of bondage their life is significantly reduced.

How to find the white-faced dolphin?

White-skinned handsome man has a strong physique. He is one of the largest among his fellows and can reach a length of up to 3 meters and weigh an average of 280-300 kilograms. The white-faced dolphin is easily recognizable by the dorsal fin, curved in the form of a sickle, a massive tail and wide white stripes along the sides of the animal. Well developed pectoral fins occupy almost 20% of the body.

The main part of his body is colored gray or darker. He got his name because nature painted his belly and face white. The dolphin’s nose is quite small - about 5 centimeters, which gives the appearance of white-dormitory a certain charm and special appeal. And it is not necessary that the nose should be white, it can be in the color of the body.

It is interesting! White-faced dolphins are able to make long jumps of 10 meters over water at a speed of 30-40 kilometers per hour.

Where to look for a dolphin with a white muzzle?

This representative of cetaceans lives in northern latitudes. Most often it is seen in the waters of the North Atlantic, sometimes in the region of Labrador, Southern Greenland, and near Iceland. His house is located near the coast of Norway and the UK, less often they swim up to Portugal and Turkey.

In Russia, you can see the white-faced dolphin in the Baltic or Barents Sea - near Murmansk and the Rybachiy Peninsula. There were cases when these dolphins were seen in the Gulf of Riga and Finland, but scientists believe that this is an exception to the general rules.

Usually these mammals try not to descend to a depth of more than 200 meters.

It is interesting! White Sea Dolphins are real naughty ones. They love to jump high out of the water and with a bunch of splashes flop into the sea water.

Resident of the Red Book

Because of the small area of ​​distribution, the white-faced dolphin has been little studied by scientists. For this reason, the cetacean has been assigned the third category of rarity, and it is listed in the Red Book of Russia, but it does not refer to an endangered, but to a small species, distributed only within a small area. Today, the total number of the white-faced family is about 100,000.

Only the killer whale is the natural detractor of the white-faced dolphin. More mammal suffers from polluted environment with heavy metals and organochlorine compounds. Although scientists say there is no cause for concern, and their population is stable, and the number of representatives does not decrease, but the white-faced representatives need human protection more than ever.

They often die in fishing nets. In addition, science can not explain the phenomenon characteristic of this species - many dolphins themselves are thrown on the shore and dry out in the absence of water.

In addition to this, fishing for this species of dolphin was developed in the UK and Norway. Now the hunt for them is not so common.

What's on the white-sided swimmer's menu?

22-28 pairs of teeth about 7 millimeters long do an excellent job with food. Sometimes such a smile in the whole snow-white row scares people, although there is no reason for this - the white-faced dolphins are very kind and friendly.

In the menu, cetaceans with a white face are mostly small fish - cod, navaga, herring and capelin. Sometimes squids, mollusks and crustaceans fall on the sharp tooth.

It is interesting! White-faced dolphins love company. Very often they are seen near the humpback whale.

You can add this report and description of the white-faced dolphin with this small video.

Hope your classmates will like your story. Look into the projects of "School" more often, we have a lot of interesting things.

Where does the white-faced dolphin live?

White-faced dolphin - a resident of northern latitudes. The area of ​​distribution of this species is very small, it represents only a small part of the North Atlantic, from Labrador, South Greenland, Iceland to the Baltic Sea. Occasionally dolphins swim to the shores of Portugal and Turkey. Most often they are found off the coast of Norway, the United Kingdom and the Faroe Islands. Throughout their range, animals try to adhere to waters no more than 200 m deep.

How does it look

White-faced dolphin has a dense build. The body length of adults varies from 2.3 to 3.1 m, and the maximum weight can reach 350 kg. Toddlers are born with an average body of 1.1 m weighing about 40 kg. The white-faced dolphin can be recognized by the sickle-shaped curved dorsal fin and wide white strips of irregular shape running along each side of the body. English (white-beaked) and Latin (albirostris) species names are literally translated as “white-eyed”, but at the same time the beak of these dolphins is not always painted white.

The nature of the white stripes and spots is very changeable, this feature helps scientists, employees of dolphinariums and research stations to distinguish between individual individuals. The color of the fins also varies from black to pearl gray.

Lifestyle and Biology

Despite the fact that the white-faced dolphin is endemic to the North Atlantic, it is not as well adapted to living in this region as beluga whales or narwhals. White-sided dolphins live in groups of shoals. The average number in the joint is 20–30 individuals. These are sociable, inquisitive and mobile animals, which can often be seen in the company of other members of the family. White-faced dolphins accompany such sea giants as the fin whale and humpback whale. White-sided dolphins hunt for small gregarious fish: cod, haddock, European hake and others, as well as squid and crustaceans.

These marine mammals have a very rich vocal range, including screams, whistles, clicks and many other types of vocalizations. Pregnancy lasts about 11 months. Females with calves are usually kept apart from others. It takes a child from 7 to 12 years to grow up, get stronger and take on the baton to continue the race. Typically, puberty occurs when the length reaches 2.5 m. The average lifespan is 30–40 years.

Listed in the Red Book

Despite the fact that the white-faced dolphin has never been commercially targeted on a large scale, in some countries, such as Norway, the Faroe Islands, Greenland, Iceland and Labrador, these dolphins were systematically caught for use in the food industry. In general, the global population of this species is in a stable position. The total number of animals is estimated at 100 thousand individuals, and at the moment there is no tendency to reduce it. Like other cetaceans, white-faced dolphins are subject to drying, the exact reasons for which are not fully established. In addition, there have been cases of death of animals in fishing nets. One of the most serious threats to this species is the pollution of waters with organochlorine substances and heavy metals.

It is interesting

Dolphins - one of the most highly developed and at the same time mysterious creatures on earth. These animals not only help their relatives out of trouble, but very often come to the aid of people. They are pushing weakening dolphins from their flock to the surface of the water to make their breathing easier, trying to help out animals entangled in fishing nets, save the lives of shipwrecked and drowning people. American scientists from the University of St. Andrews, Florida, found that dolphins distinguish each other not only by voice but also by name. At birth, the baby's mother produces a certain single whistle, which serves him as a name. Subsequently, such a whistle is fixed, and other members of the pack can play it. So far, this data has been scientifically confirmed for bottlenose dolphins.

Classification

Kingdom: Animals (Animalia).
Type of: Chordata (Chordata).
Class: Mammals (Mammalia).
Squad: Cetaceans (Cetacea).
Family: Dolphin (Delphinidae).
Rod: Dolphins short-headed (Lagenorhynchus).
View: White-faced dolphin (Lagenorhynchus albirostris).

White Sea Dolphin. Description

This type of dolphin is not the largest, an adult animal has a length of approximately two and a half to three meters. A distinctive feature of the species is a fairly high fin, strongly curved back.

The crests on the tail are slightly less pronounced than in most other species, but the front fins are somewhat longer. Most of the body has a dark, almost black color, and the belly is lighter, often with a cream-colored shade. It is the same with fins that have a darker color above than the bottom.

The frontal tubercle and beak of the white-mouthed dolphin are very bright, hence the name of the species. The bill is filled with several rows of teeth, each of which is about 25-26. Their size is about six to seven millimeters.

White Sea Dolphin from the Red Book

The distribution area of ​​the animal is quite extensive and includes the North Atlantic waters, as well as the Barents and Baltic seas. They can easily be found both off the coast of cold Greenland and in the warmer waters of the Gulf of Finland.

Often they are found off the coast of Norway, sometimes they even swim into the depths of the fjords. However, this happens infrequently. In addition, they can be seen in North American waters, off the coast of Labrador, as well as in Iceland.

In Russia, white-faced dolphins are most often found off the coast of Murmansk and the Rybachiy peninsula.

Lifestyle

The white-faced dolphin from the Red Book of Russia is a social animal, like most other species of marine dolphins. Therefore, they live, as a rule, in small groups of 5-6 individuals. However, sometimes they get together in fairly large groups in which there can be up to several hundred members.

The main food for them are small fish living in the bottom zone. Such fish include herring, capelin, cod and others. In addition to fish, dolphins consume cephalopod mollusks, and sometimes they do not disdain hermit crabs.

The mating period is in the middle of summer, although sometimes animals can breed at other times of the year. A newborn baby can be quite large and make up almost half the maternal length. Of course, it’s not easy to bear such a young one, and feeding is even more difficult, so they multiply very slowly.

This type of marine mammal has never been in great demand among hunters because it does not represent much value.

The lack of industrial fishing for white-faced dolphins allows the animal to maintain a fairly large population in the waters of the North Atlantic. Why, then, is it listed in the Red Book in Russia? The answer is simple: in the waters of the Russian Federation it is difficult to meet these marine inhabitants, therefore, specifically for our country, they are considered rare.

Despite the fact that animals are not killed by thousands, like many whales, they are sometimes hunted by the Greenland Eskimos, who are allowed to fish for any marine life, even those that are considered endangered species.

The reason that the number of animals is rather small is not their extermination, but extremely slow reproduction.

Diseases

This species is poorly understood, so almost nothing is known about the diseases. There is reliable data only on some bone diseases and abscesses of the teeth. There are also three types of parasitic worms, which were found in the body of some dolphins.

A phenomenon that science cannot yet explain is also connected with the white-faced dolphins. The idea is that some individuals dry for unknown reasons. Over the past century, several hundred such cases have been observed, and in different parts of their habitat.

How to deal with this, while scientists also do not know, but they are trying to find the answer, applying for this purpose all the forces and resources that modern science has.

Conclusion

Based on the above, it is safe to say that the white-faced dolphin, the photo of which you can see below, is certainly a unique species that you need to save by all means.

The leaders of the countries in whose waters these wonderful animals can be found are taking measures to preserve and increase the population of dolphins. Despite all the actions taken, the number of individuals continues to decline. Although it is too early to talk about the risk of extinction, but measures to protect this species need to be strengthened, otherwise in a few decades the white-faced dolphin may disappear completely, like many other animal species.

There are a lot of problems to fight. Poaching and unknown diseases can also be attributed to them, as well as numerous cases of death of animals in fishing nets, into which they accidentally fall and can no longer escape from there.

In Russia, measures are being taken to preserve this marine inhabitant, but it is not yet possible to talk about any high results and effectiveness. The fact that it is listed in the Red Book does not change the situation too much, because environmental protection in our country is poorly developed. Government agencies are not able to work fully and effectively due to lack of funding and labor. The resources necessary for the qualitative implementation of productive work are also lacking today.

White sea dolphin: description

Mostly people can communicate with dolphins and view them at close range in dolphinariums. In captivity, classic gray animals are usually kept, but sometimes white-faced beauties are also found on shows.

They belong to the order of cetaceans and stand out among the rest with large sizes. An adult white-faced dolphin weighs about 270-280 kg with a body length of 3-3.5 meters. Males are much larger than females. You can recognize them by large fins on the chest, developed ridges on the back and a massive tail. Unlike their gray counterparts, animals of this species have a small (about 5 cm) beak, thanks to which beautiful creatures look kind, sweet and harmless.

The color of the back and sides of the dolphin is dark, the belly is contrasting white. Animals have 22-28 pairs of thick, large teeth up to 7 mm long. For humans, these sea creatures are not dangerous, but there have been cases when a dolphin accidentally wounded people during the game. So it does not hurt to behave carefully next to these beauties.

Habitat

If we consider the global habitat of the white-mouthed dolphin, then it occurs in its natural environment in the northern Atlantic. From Labrador, South Greenland, the Strait of Davis, Iceland and the Barents Sea to the south to the shores of France, the Bay of Massachusetts, the Baltic and North Seas, inclusive.

Migrations of these animals are not studied at all. In the Davis Strait, for example, they appear at the same time as porpoises when the white whale and white whale leave to the north. Leave these same places around November, at the end of autumn.

On the territory of Russia the white-faced dolphin is found only in the Baltic and Barents seas.

Interesting details about the life of white-faced dolphins

The life of white-faced dolphins is very interesting and mysterious. People today could learn some interesting details about these animals with white tummies and cute noses.

  • Dolphins are known for their playful character, at any opportunity they are ready to frolic. Their favorite entertainment is to jump out of the water, roll over in the air and flop back. When a body strikes the water surface, a million splashes rise. Isn't it a fun game?
  • Under water, white-faced dolphins spend a lot of time chasing seaweed. Watching these games of playful animals is very interesting.
  • Until now, scientists have not been able to give an exact answer as to why, very often, these beautiful creatures are thrown onto the shore themselves and die.
  • Беломордый дельфин издает звуки, график которых имеет форму цветка. None of the sea creatures are capable of it.
  • Scientists have established that ultrasound dolphin has a positive effect on human health and contributes to the healing of diseases.

Red Data Book of Russia: White-faced Dolphin

It is known that animals of this species are listed in the Red Book of Russia. This is in spite of the fact that they have never been of interest to commercial fishing. Although in countries such as Greenland, Norway, Labrador, Iceland they were caught and used in the food industry.

Considering the population on a global scale, we can conclude that the representatives of this species are still in a stable position. To date, there is no threat of extinction or reduction in the number of animals. The total number of adults is approximately one hundred thousand. In such a situation, if in the future fishing of sea beauties will not be opened, it will not be necessary to include them in the Red Books.

It is very sad to list endangered species of animals in Russia. The white-faced dolphin, unfortunately, is also included in this list. But let's hope that in the future, thanks to the careful attitude of man to nature, rare animals will not be on the verge of extinction.

Appearance

White Sea Dolphin is a rather large in size aquatic inhabitant. The average length of an adult animal is three meters with body weight up to 350-355 kilograms. For such an aquatic inhabitant, the sides and upper part beyond the area of ​​the dorsal fin are of a grayish-white coloration. The lower part of the body has a white color, and the upper side in front of the dorsal fin region is grayish-black. The dorsal fin and flippers of the white-faced dolphin are distinguished by a blackish color.

The beak of the aquatic inhabitant is usually white in color, but in some individuals it is ashen-gray. White-faced dolphins have 25-28 well developed and fairly strong teeth on each jaw. Representatives of the species of dolphin from the order of the Cetaceans and the genus Short-faced dolphins are characterized by the presence of 92 vertebrae, which exceeds the number of such formations in any other species of the family Delphinidae. White-faced dolphins can swim, easily reaching speeds of up to 30 km / h and periodically diving to a depth of 40-45 meters or even more.

Sexual dimorphism

The female dolphin has a common urogenital fold extending parallel to the belly area.. It is also located anal output. Through the anterior fibrous dense connective tissue in females, a well-developed clitoris appears, represented by the cavernous body and thick albumin membrane. The external sexual organ of a female dolphin is the small and large labia.

It is interesting! It should be noted that the males of the white-faced dolphin, as is customary, are much larger than the females.

For the sex organs of male dolphins, the presence of the perineum is characteristic, which separates the genital fold and anal output. Dolphins have no scrotum, and the location of the testes is the abdominal cavity. Under conditions of body temperature at a level of 37 ° C, the process of spermatogenesis proceeds in a normal mode, and the critical temperature conditions for this process are 38 ° C.

Habitat

The aquatic mammal lives in the North Atlantic from the coast of France to the Barents Sea. Also, the natural habitat of a representative of this species of dolphin from the order of the Cetaceans and the genus Short-faced dolphins is limited to Labrador and the waters of the Davis Strait, to Massachusetts.

According to the observations of experts, this aquatic inhabitant is very widespread in the waters of the Norwegian Sea and in the waters of the North Sea, inhabiting the territories along the coast of Great Britain and Norway. Rather large herds of the white-faced dolphin are found in the Varanger fjord. The population in this place reaches several thousand heads in each pack.

In winter, the white-faced dolphin population prefers to migrate in the southern areas of the range, where warm and comfortable climatic conditions are noted. In Russia, such a mammal is found everywhere along the whole Murmansk coast and near the Fishing Peninsula. There are well-known cases of the presence of white-faced dolphins in the Gulf of Finland and Riga, but such a location of mammalian aquatic creatures is most likely a kind of exception. A number of individuals are found along the coastline of Sweden in the Baltic.

In the waters of the Davis Strait, white-faced dolphins appear in the spring period together with porpoises, after this territory is left by the narwhal and the white whales, which are a real threat to rare mammals. However, by November water inhabitants try to migrate as quickly as possible closer to the south, where the climate remains as comfortable as possible.

The diet of the white-mouthed dolphin

White-faced dolphins are classified as aquatic predators. Such representatives of the dolphin species of the order Cetaceans and the genus Short-headed dolphins feed mainly on fish, as well as crustaceans and molluscs.

Food such large aquatic inhabitants get their own, so the diet of the animal is quite diverse.

Mammal eats cod, herring, capelin and other fish. For humans, dolphins pose absolutely no danger. Nevertheless, cases where aquatic inhabitants bring some inconveniences to people are fairly well known. Very good-natured and incredibly cute animals madly love to play and frolic. When underwater games dolphins chase large algae.

It is interesting! After eating edibles, white-faced dolphins are divided into several small groups that quickly move in different directions.

In their free time from searching for food and rest, adult cetaceans prefer to fool around and accelerate to 35-40 km per hour, and also make simply dizzying jumps over the water. Scientifically proven is the beneficial effect of ultrasound produced by dolphins on humans. Thanks to playfulness, curiosity and good nature, such mammals are actively used in dolphinariums and water parks.

Reproduction and offspring

The period of active mating and the emergence of offspring into the world falls exclusively on the warm summer months. The average gestational age of the white-mouthed dolphin is about eleven months.

Some time after the birth of dolphins, females with them try to keep apart from other members of the family. It takes seven to twelve years for small dolphins to grow, mature and reach puberty. Throughout this period, the female teaches her offspring with the most basic skills, including foraging and maintaining her own life in adverse conditions.

Amazing and very noble animals that live in the water element, have just the richest and peculiar vocal range, are able to produce a lot of whistles and screams, various clicks, as well as many other different types of vocalization. No wonder all dolphins, including the white-faced, are famous for their level of development. Often, such animals try to help not only their fellow tribesmen, but also people who are in trouble, shipwrecked or drowned.

Natural enemies

The main source of danger for white-faced dolphins is people, their vital activity, harmful industrial emissions into the sea. The natural enemies of a friendly and cheerful animal are almost completely absent.

According to estimates, the average number of representatives of this species reaches 100 thousand. Part of the mammals' aquatic creatures die when they enter the fishing nets, but the most serious threat to the life of white-faced dolphins is water pollution with hazardous organochlorine substances and heavy metals. As measures of protection can also be considered anti-poaching.

It is interesting! Despite the fact that the mammal is not an object of commercial fishing and on a large scale, in some countries, such animals were regularly caught for use in the food industry.

Older dolphins often face significant difficulties associated with the jaws. As a rule, old mammals suffer from diseases represented by alveolar abscesses, bone exostoses and synostosis. There are also nematode parasites that adversely affect the overall health and life expectancy of dolphins.

Population and species status

Considering the population of large cetaceans on a global scale, it is possible to draw conclusions that the representatives of this species are currently in a rather stable position. The Red Sea Dolphin from the Red Book is a rare, small species of nature that needs protection and conservation measures.

It will also be interesting:

zoo-club-org