Dolphins are what type of animal. Black Sea dolphin. Types of dolphins. What do dolphins look like?
home Almost all species of dolphins live in warm salty waters . There are 47 of them in total. These are the indigenous inhabitants of the seas and oceans. But besides marine mammals, there are also river dolphins
, representing a separate family, which includes 6 species. These animals live in the rivers of India, China and South America. Their habitat is the Ganges, Indus and Brahmaputra in India. In China they can be found in Lake Dongtinghoe, and in South America they have chosen the Amazon, Orinoco and La Plata. River dolphins they are inferior in size and weight to their marine relatives and have a more primitive brain structure. The body length of these animals usually ranges from 1.5 to 2.5 meters, and the weight is never less than 40 kg, but does not exceed 120 kg. The bodies of river animals are usually brown or almost White color , sometimes it’s true that you come across dark ink. The vision of these mammals is very weak or almost completely absent. The same thing characteristic difference
from their marine counterparts - these are cervical vertebrae. They are not fused into a single bone like those of ocean inhabitants, but are divided just like those of land mammals. Dolphins for the most part are heat-loving animals. Only people love cool waters individual species . These include striped dolphin . It is common in the North Pacific Ocean. It can be found off the coast of Sakhalin and the Kuril Islands, in the waters adjacent to California and Japan. This mammal reaches a length of 2.2-2.3 meters. Average weight
is 140 kg. The maximum weight of males can vary between 180 kg. Females are never lighter than 100 kg.
This is a very lively, fast and energetic dolphin. It can often be seen from the sides of ships. Swift, graceful bodies with dark narrow stripes on the sides can accompany the ship for a very long time. Moreover, the animals not only swim in a parallel course, but also easily overtake the floating craft, cross its path and make various jumps and pirouettes. The striped dolphin's closest relative is. Along with the shores of Canada, England, Korea and Japan, it also loves the warm waters of the Mediterranean and Black Seas. It can also be found off the coast of Australia, where the animal feels quite comfortable. The dolphin is very graceful and the fastest of all its sea counterparts. In water it easily reaches speeds of 60-70 km/h. Loves to jump. Their height reaches 5 meters.
The color of the squirrel is very beautiful. The back is black with a greenish tint, and the belly is white. The eyes are surrounded by black circles. The dolphin reaches a maximum length of 2.4 meters at medium length 2 meters. The weight of the animal is about 110 kg. The common dolphin has a high dorsal fin: its height is 80 cm. These mammals live in large schools and love to frolic near the water surface.
Dolphin species would have lost a lot if there had not been such a representative among them as bottlenose dolphin. This is a large mammal, reaching a length of 2.3-3.2 meters. Sometimes you come across bottlenose dolphins of more impressive size with a body length of 3.6 meters. The mass of this dolphin is usually within 300 kg. The maximum weight reaches 400 kg. The habitat of this animal extends to all temperate and warm waters World ocean. Bottlenose dolphins can be found in Cherny and Mediterranean seas, V Indian Ocean, in the Atlantic and in the Pacific, where he really loves the waters washing the shores South-East Asia and Australia.
The body color of different individuals is not the same, but varies in shade. Mostly dark brown back and gray belly predominate. There are animals with white bellies. Sometimes you can find a representative of the species whose entire body is a uniform gray color. The speed that a bottlenose dolphin develops in water is 40 km/h. He developed a very good and friendly relationship with the person. The dolphin is highly trainable and even learns some words spoken by people. This species performs in dolphinariums more often than any other, impressing spectators with its skill.
Without exception, all species of dolphins have one characteristic feature. Sometimes they are in large quantities wash ashore and die. Experts explain this phenomenon in different ways. The prevailing point of view is that such suicides are the result of the work of certain brain centers of the animal, directly related to the generation of high-frequency sounds. Sometimes the established oscillation frequency earth's surface resonates as a result of the influence of external oscillatory sources on it. These can be wind, tremors earth's crust or the operation of ship radars.
The modified frequency signal may match the sound made by a wounded dolphin. It’s like a person to whom sometimes the howling of a storm outside the window seems like the cry of a child. Let us remember A.S. Pushkin: “Then she will howl like a beast, then she will cry like a child.” A nearby flock perceives such a signal as a call for help. She quickly rushes to the coast, washes ashore and dies. Similar actions are observed in all marine mammals that do not abandon their fellows in trouble (for example, in the same whales), which once again confirms the correctness of this version.
Common dolphin, or common dolphin. Habitat - open water and coastal zone. The convex fat pad in front is clearly delimited by the right and left grooves, converging at an angle at the base of the beak. The dorsal fin is high and slender, sitting in the middle of the body length. The pectoral fins of embryos are relatively larger than those of adults. The index of distance from the end of the muzzle to the pectoral fins also decreases with age: 28.5% in newborns and 23% in old ones.
Body type. Body length is about 160-260 cm, but in the Black Sea it does not exceed 210 cm. Females are on average 6-10 cm smaller than males. Dolphins are very slender, with a long beak, sharply demarcated from the fat pad by grooves. There are 2 deep longitudinal grooves in the sky. The skull is characterized by a very long (1.5 - 2 times longer than the braincase) rostrum, on the palatal side of which there are two (right and left) deep longitudinal grooves. The premaxillary bones in the middle part are fused by the edges; in front a little, and in the back they diverge much more strongly and cover the bony nostril from the sides.
The status of the species is widespread.
The number of groups is 10-500 (1-2000).
The location of the dorsal fin is in the center.
The weight of the newborn is unknown. Adult weight - 70-110 kg.
The length of a newborn is 80-90 cm.
Body coloring dark above, white below; on the sides - with a complex pattern of intermediate tones, namely: two gray elongated fields and 1-3 gray side stripes directed from the genital area to the anterior half of the body. From the base of the dark pectoral fins to the chin there is a dark stripe and along the bridge of the nose (from eye to eye, at the anterior edge of the fat pad) a dark stripe. The tail lobes and dorsal fin are dark. The stripes on the sides of the body are not equally sharply expressed, but in the Far Eastern white sided ( D. d. bairdii) are completely absent (in the latter, the color of the upper part of the body is sharply separated from the light lower part, without transitional tones).
Nutrition. Pelagic fish, rarely molluscs and crustaceans. In the Black Sea, the main food items are sprat and anchovy; secondary objects - pelagic needles, haddock, red mullet, horse mackerel, crustacean - sea cockroach Idothea algirica; tertiary species - mullet, mackerel, bonito, blennies, greenfinches, herring Caspialosa, as well as random shellfish and shrimp Crangon crangon.
The diet of non-Black Sea white drums included: herring, capelin, saury, anchovy, mackerel, mackerel, sardines, mullet, Stingray, flying fish, and also (in the Mediterranean Sea and Atlantic Ocean) cephalopods- squid.
On Far East sometimes eats schooling fish, congregating together with bottlenose dolphins and short-headed dolphins. In the Mediterranean Sea in winter, it flushes anchovies and sardines from the depths to the surface. Fishermen take advantage of this and deploy nets in the winter feeding areas of dolphins, catching the rising fish. Largest quantity Empty stomachs in dolphins are observed in the summer, which coincides with the height of sexual activity and puppies, when the need for food decreases. The highest body fat content of Black Sea dolphins is observed in March, when the water is coldest, and the minimum in August, when maximum temperature environment.
Habitats. The common dolphin is distributed in the world's oceans as widely as the bottlenose dolphin, but adheres to open sea. Found from the latitudes of Northern Norway, Iceland, Newfoundland, the southern part of the Kuril ridge, Washington State to the southern latitudes of Tristan da Cunha Island, South Africa, Tasmania, New Zealand. In this area there are several subspecies, in the waters of our country - 3: 1) Black Sea - D. d. ponticus Barabasch, 1935; 2) Atlantic— D. d. delphis L., 1758 and 3) Far Eastern - D. d. bairdii Ball, 1873. The first is smaller than the other two, the second is larger than the first, but is similar to it in color, and the third is similar in size to the second, but differs from the first two in color, as well as large indices1 of the width of the rostrum, orbital width and length of the lower jaw.
Pelagic by nature, the common dolphin has a very wide range: from the coast of Norway (Finmarken Peninsula), Iceland, southern parts Greenland, Newfoundland, Okhotsk and Bering Seas to the Cape of Good Hope, Tristan da Cunha Island, the southern parts of New Zealand and Tasmania. Particularly abundant in the temperate waters of the northern hemisphere (Gascony Bay, Brittany coast, Mediterranean and Black Sea, waters of New Scotland, Japan, California, as well as Australia and New Zealand); there are small quantities in tropical zone, where it is known from the shores of Rio de Janeiro, Sierra Leone (West Africa), Jamaica, Bahamas, Gulf of Mexico, India. In the northern hemisphere it seems to visit higher latitudes than in the southern. In the Barents Sea, fruit juice has not been reliably recorded; scarce in the Norwegian Sea; occasionally penetrates into the Baltic Sea. The Black Sea population of common dolphins is well isolated, does not migrate through narrow straits into the Mediterranean Sea, and is believed to have appeared in the Black Sea before the bottlenose dolphins and porpoises living here.
The Black Sea common dolphin feeds in the upper layer of the sea and does not dive deeper than 60-70 m, but the ocean form catches fish living at depths of 200-250 m. When gathering food, the common dolphin gathers in large herds, sometimes together with other species - pilot whales and short-headed dolphins. It treats humans peacefully, never bites, but does not tolerate captivity well.
White sideds often live in families, which are supposed to be composed of the offspring of several generations of the same female. However, males and lactating females with young animals, as well as pregnant females, sometimes form separate (apparently temporary) schools. During the period of sexual activity, mating groups of sexually mature males and females are also observed. Mutual assistance reaction has been developed.
They live up to 30 years. Dolphins are excellent at navigating in water using their echolocation apparatus, so they can frolic safely even in minefields. Their vision is less developed than hearing and is of less importance in water, where the visibility range does not exceed several tens of meters. In the air, dolphins see and react to hand waves by closing their eyelids from a distance of up to 2 m. In the air, the body temperature of struggling dolphins quickly rises from normal (36.°5) to 42°.6, when heat stroke occurs. However, in water, intense muscular work does not cause an increase in body temperature. Excess heat is given off through the surface of the dorsal, caudal and pectoral fins, which are perfect heat regulating organs. In connection with this function blood vessels in the fins they have a specific arrangement in the form of bundles, in the center of which there is an artery, and surrounded by 6-12 thin-walled veins.
The vascular bundles, approaching the skin of the fins, break up into smaller and smaller ones, but do not lose their specific structure. With such a device and the presence strong game vascular bundles can either very effectively transfer excess heat brought by arterial blood, or sharply reduce heat transfer by reducing blood flow to the skin of the fins. Therefore, in living dolphins, one can observe a difference in temperature on the surface of the fins and on the side of the body of up to 10-11°. If there are white spots on the fins, they turn pink every time with increased blood flow.
Common dolphins tolerate captivity worse than bottlenose dolphins and short-headed dolphins. As a pelagic species, the white drum rarely dries out on the shore and even more rarely enters river mouths. More often than other dolphins, they are chased by moving ships. It is possible that the torn edges of the fins and large traces of damage to the skin are caused to the dolphins by the propellers of the ships during such a chase. Occasionally, single individuals join (apparently during feeding) pods of other dolphin species, such as pilot whales.
Sounds, sounds made by dolphins are quite varied and are in the nature of signals. The most commonly heard whistling (especially in excited flocks), reminiscent of the squeaking of mice. With a thin squeak lasting about 1 second. Air bubbles are released from the blowhole and rise to the surface of the water. If a squeak is made in the air, you can see how the blowhole valve makes a barely noticeable movement with its edges. From sounds with a frequency of up to 12,000 hertz, creaks heard during feeding and similar to meowing, as well as frequent crackling sounds with a cycle shorter than 0, are recorded on magnetic film (except for whistling). ,2-0.4 seconds, no longer perceptible to the human ear and intended for echolocation. Sound is supplied using air sacs and a system of sinuses in which resonating frequencies are excited.
Reproduction. Males predominate in catches and among embryos (about 53%). The height of mating and puppies falls on summer months, but the breeding season is extended over six months (from May to November). In the Black Sea it was seen in summer time departure of females from the shores in front of the pup. Childbirth takes place under water (regardless of the weather) and only very rarely can you see the tail of a newborn baby in the female’s vulva when it emerges. The newborn immediately swims well. The placenta lingers in the female’s birth canal for up to 1.5–2 hours.
The size of newborn males is 85-95 cm, and females - 80-85 cm. Females apparently give birth 1-2 years later, after a 10-11 month pregnancy. The possibility of annual births is evidenced by frequent findings of small embryos in lactating females. However, the presence of 25% of barren females among those who have already given birth indicates an alternation of three annual pups with a fourth occurring two years later. The lactation period, judging by this frequency, lasts 4-6 months. Milk contains 41.6-43.71% fat, 4.88-5.62% protein, 1.45-1.49% sugar, 0.45-0.46% ash and 48.76-51.62% water.
Females, like bottlenose dolphins, probably protect the calf in the first weeks of its life, and therefore separate from other relatives, moving away from the shores. This is confirmed by observations of the differentiation of dolphin schools by sex and age. In winter there are two types of schools - of adult males and of adult females with young animals, and in summer there are six types: pre-pregnant (pregnant females); children's (nursing sleds with babies); nuptials (sexually mature individuals of both sexes with a small part of sucklings that have almost finished milk feeding); immature; remnants (in spring and early summer) of winter schools of males that have not yet broken up; the same remains of schools of females. The female, judging by the size of the embryo, can mate according to at least a month before the end of feeding the baby, with which the connection is sharply weakened. Mating is accompanied by fights between males, as evidenced by bite marks, common on the body of adult males, but rare on the skin of females. Only males bite, and most intensely during sexual activity.
The timing of puberty is not precisely established. The idea that sexual maturity is reached at 2-4 years of age is not confirmed by the latest data from the Florida Aquarium, where the first mating of a bottlenose dolphin (a species close to the white sided dolphin) was noted at 6 years of age, and birth at 7 years of age. Minimum size sexually mature females in the Black Sea are 140 cm and males are 150 cm, and maximum dimensions immature females are 160 cm and males are 180 cm. All females over 170 cm in length were sexually mature and often, with almost similar sizes, had a different number of scars on the corpus luteum. For example, females 170 and 173 cm long had only one scar each, and a female 175 cm long had 15 scars.
Dark V-shaped "cape" with a depression under the dorsal fin
- the pattern on the sides resembles hourglass
- white belly and lower sides
- all fins are dark
- yellowish spot on the sides
- dark line from pectoral fins to beak
- protruding dorsal fin and beak
- high activity
Teeth. The number of teeth is from 160 to 206, their length is from 4 to 7 mm and the greatest thickness is from 2 to 3 mm (on average 2.3 mm). The teeth are almost not worn out. The greatest condylobasal length of the skull is 485 mm (in the Black Sea 421 mm).
Fishing. We catch dolphins with purse seines in the Black Sea; products are processed at fish factories in Novorossiysk and Tuapse. Anapa and other cities.
The average weight of white drums is 43-59 kg, of which 29-43% is fat with skin. A young female 143 cm long weighed, according to our data, 32 kg, including (in g) subcutaneous fat 10,980, muscles of the back and tail 6350, spine 2550, ribs with intercostal muscles 1850, fat pad 520, dorsal fin 250, pectoral fins 475, tail blades 440, lower jaws 480, tongue 175, brain 670, intestines 967, esophagus 230, liver 596, lungs with larynx 1000, heart 170, both kidneys 186, stomach 198, other parts (blood, skull, etc.) d.) 3913
The cod oil substitute “delphinol” is produced from lard; fat is used in the paint and varnish industry, as well as for lubricating precision mechanisms, producing technical machine oil, etc.
Literature:
1. “The Life of Animals”, in volume 7 / Mammals / - Edited by V.E. Sokolov - 2nd ed., revised - M.: Education, 1989 - 558 p.
2. Sokolov V.E. Rare and endangered animals. Mammals: Reference manual.-M.: Higher school, 1986.-519 pp.
3. Professor Tomilin Avenir Grigorievich. Cetacean fauna of the seas of the USSR, 1961
Probably, many at one time wondered: is a dolphin a fish or a mammal? After all, like many representatives of fish, it lives in the oceans and seas and leads a lifestyle similar to them. However, dolphins are aquatic mammals that belong to the class of cetaceans.
Relatives of this animal are whales and killer whales. More ancient, on this moment The already extinct ancestors are considered to be predators - sea otters, which, like dolphins, lived in the water.
Main features of a mammal
This animal species is diverse, extensive and there are about 50 various types . Dolphins are ancient mammals that arouse genuine interest among people. They are called intelligent and understanding beings.
The appearance of the dolphins is several unusual for a marine life. There are no scales on its body, like those of fish; on the contrary, its cover is streamlined and slippery, so the animal is well adapted to both the depths and the surface of water.
Description and characteristics dolphins:
Skin and color of a mammal
The color of the animal can be varied.
- Plain (gray, pink, black).
- Two-tone (black and white shades).
These mammals are very nimble and energetic, they move in water space with high speed causing the top layers of skin to wear away. That's why dolphins have a deep layer skin, which is constantly updated. This process is very fast; the upper and lower layers change within a day. Skin cells are constantly dividing, and about 30 layers of skin can be replaced in a day. Continuous molting is the main condition of these intelligent mammals.
Intelligence
A little known but much discussed aspect is how intelligent these animals are. Almost the entire life of a mammal - free time when they can do whatever they want. He spends it on fun games, communication and even sex. Mammals love to jump out of the water, spin and twist in every possible way. Despite their carefree existence, dolphins are considered very smart mammals, because they are able to communicate, think, follow commands, and even save people.
The brain of an animal, in relation to the proportions of the body, is large, and if compared with monkeys, dolphins are much larger. Also, thanks to research by scientists, it was revealed that the mammal has a highly developed vocal vocabulary. Not to mention self-awareness, emotional empathy, social development, mutual support and mutual assistance.
Nutrition
The main food of dolphins is undoubtedly fish. The animal prefers to eat small fish such as anchovies and sardines.
It should also be said about how they catch their prey. First a school of dolphins use their main weapon - echolocation scanning the water for fish. Further, if a school is detected, they approach at high speed, while giving such sound signals that the fish panic and huddle together in a compact heap. This is where smart mammals know their stuff. Together, they catch prey. The possibilities of such a hunt are great. Mammals are capable of catching almost the entire school of fish.
Reproduction
Dolphins reproduce throughout the year. They mate in motion, and the birth of offspring also takes place in motion.
Pregnancy in a female lasts from 10 to 18 months. Usually, a baby is born about 60 cm in length, tail out. The newborn is so developed that from the very first minutes he begins to follow his mother. While learning in its pack, the animal becomes smarter, develops, learns to hunt fish, communicates, and soon gets its own food.
Animal enemies
The most evil The enemy of the dolphin, like all inhabitants of the ocean, is considered to be the shark, as well as some relatives of the mammal (killer whale). Since ancient times, people began to hunt dolphins. The indigenous people of the north caught the mammals and extracted only the meat. This is a high degree of cruelty. Currently, in some countries, the barbaric tradition of hunting dolphins remains.
These mammals are dying due to human activities. Animals often get caught in fishing nets. They die from oil spills into the sea. Injuries caused by ship propellers affect the lives of dolphins and their deaths. Man contributes to all this, even if unconsciously, but he has made a lot of efforts that contribute to the destruction of dolphins. But some of them are already listed in the Red Book.
Dolphinariums, water parks with complex animal training, everything this contributes to the destruction of these intelligent mammals. This is worth thinking about.
Niramin - Nov 26th, 2015
Dolphins are mammals of the dolphin family from the order Cetacea. There are about 40 types of them. The largest species is the killer whale.
What do dolphins look like?
They have a bare, streamlined body, an elongated muzzle, and a pointed dorsal fin. The eyes are small and lack sharp vision. Skin color can be of two types: plain - gray, Pink colour, or contrasting - when large areas are painted black and white.
Depending on the species, there are different weights: from 40 kg to 500 kg. The body length reaches 1.2 m, but the killer whale can be up to 9 m and weigh 7.5 tons.
They may not sleep for up to 5 days, but this does not affect their health. If they sleep, then very little. If they sleep for a long time, they can suffocate and die. When they rest, one half of the brain is asleep, the other is awake, then they can breathe.
Dolphins are warm-blooded animals. Their body temperature is the same as a human's, 36.6°C.
They have echolocation - they determine the location of an object by capturing a reflected sound wave. They communicate between relatives using sounds of varying durations, and warn about impending danger with sound signals.
Where do dolphins live
They live in almost all the seas of the world and in shallow tropical latitudes of the oceans. You can also find it in the Black Sea. Only 5 species of river dolphins live in rivers.
Dolphin feeding
They feed on small fish - anchovies, sardines, squid, crustaceans. The killer whale prefers walruses, seals and sea lions. Interestingly, with 40 teeth, they swallow all prey whole without chewing.
Reproduction and lifespan of dolphins
Mating occurs throughout the year. The pregnancy is carried by a female dolphin, depending on the type of animal, from 9 to 16 months. Only one cub is born. The mother immediately pushes the newborn to the surface of the water so that he takes his first breath. They are fed with mother's milk for six months.
The maximum life expectancy is 50 years. In captivity, their life is shortened to 25 years, as the animals are often used to perform acrobatic stunts in dolphinariums.
See a gallery of photographs of different dolphins:
Photo: Long-beaked dolphin 
Photo: Long-snouted common whitetail 
Photo: Whale dolphins 
Photo: Orcas 
Photo: Large-toothed dolphin 
Photo: Variegated dolphins 
Photo: Gray dolphin 
Photo: Bottlenose dolphins 
Photo: Beakless dolphins 
Photo: Humpback dolphin 
Photo: Grindas 
Photo: frolicking dolphins
Video: Diving and dolphins are an explosive positive!!!
Video: Dolphins bring POSITIVITY from an eternal “smile”, friendship, loyalty.
Video: Tenerife, Canary Islands. Puerto de la Cruz. Loro Parque. Orca show Part 1
Video: Grinds
First of all, it must be said that dolphins are not fish, despite the fact that they live in water. These creatures are mammals and viviparous, just like all inhabitants of the animal world. In this case, the female gives birth to only one baby, and not many. And the mother bears her child from ten to eighteen months. The name of the animal, which dates back to the ancient Greek language, is translated as “newborn baby.” What this is connected with is now difficult to determine. Perhaps dolphins received this name for their piercing cry, similar to the cry of a child, or perhaps for their resemblance to a human fetus in the womb.
Dolphins are characterized by the presence in both jaws of a fairly significant number of uniform conical teeth, both nasal openings are usually connected into one transverse crescent-shaped opening at the top of the skull, the head is relatively small, often with a pointed muzzle, the body is elongated, and there is a dorsal fin. Very mobile and dexterous, voracious predators, living mostly socially, are found in all seas, rise high in rivers, feed mainly on fish, mollusks, and crustaceans; sometimes they attack their relatives. They are also distinguished by their curiosity and traditionally good attitude towards people. Some dolphins have a mouth extended forward in the form of a beak;
in others the head is rounded in front, without a beak-like mouth.
There are more than seventy species of dolphins in nature. They have specific similarities with each other, such as viviparity, feeding on milk, the presence of respiratory organs, smooth skin and much more. Also in dolphins different types has its own characteristics. Some animals have an elongated nasal part, while others, on the contrary, have a depressed one. They may differ in color and body weight.
Common dolphin or white sided cetacean - one of the most gregarious, playful and fast cetaceans. Its speed reaches 36 km/h, and when it rides a ship wave near the bow of high-speed ships, it reaches more than 60 km/h. Jumps "candle" up to 5 m, and horizontally up to 9 m. Immerses for 8 minutes, but usually for a time from 10 seconds to 2 minutes.
The Black Sea common dolphin feeds in the upper layer of the sea and does not dive deeper than 60-70 m, but the ocean form catches fish living at depths of 200-250 m. When gathering food, the common dolphin gathers in large herds, sometimes together with other species - pilot whales and short-headed dolphins. It treats humans peacefully, never bites, but does not tolerate captivity well.
White sideds often live in families, which are supposed to be composed of the offspring of several generations of the same female. However, males and lactating females with young animals, as well as pregnant females, sometimes form separate (apparently temporary) schools. During the period of sexual activity, mating groups of sexually mature males and females are also observed. Mutual assistance reaction has been developed.
They live up to 30 years. The sound signals of white sided dolphins are as diverse as those of bottlenose dolphins: quacks, howls, squeaks, croaking, cat calls, but whistling predominates. There were up to 19 different signals. In this species, unusually strong calls, the meaning of which has not been determined, called "shot" (duration 1 s) and "rumble" (duration 3 s) were found to have very high sound pressure (from 30 to 160 bar) and a frequency of 21 kHz.
bottlenose dolphin lives sedentary, or wanders in small flocks. The bottlenose dolphin's tendency to coastal zone explained by the bottom nature of feeding. For food it dives in the Black Sea to a depth of up to 90 m, in the Mediterranean - up to 150 m. There is information that in the Gulf of Guinea it dives to 400-500 m. Under experimental conditions in the USA, it was noted to dive up to 300 m. While hunting for fish, The bottlenose dolphin moves unevenly, jerkily, with frequent sharp turns. Her breathing pauses last from a few seconds to 6-7 minutes, up to a maximum of a quarter of an hour. Most active during the day.
Bottlenose dolphins in captivity breathe 1-4 times per minute, their heart beats 80-140 (on average 100) times per minute. The bottlenose dolphin can reach speeds of up to 40 km/h and jump to a height of up to 5 m.
The bottlenose dolphin skillfully controls the complex vocal apparatus, in which the most significant are three pairs of air sacs connected to the nasal canal. To communicate with each other, bottlenose dolphins emit communication signals with a frequency of 7 to 20 kHz: whistling, barking (chasing prey), meowing (feeding), clapping (terrifying their relatives), etc. When searching for prey and orienting themselves under water, they emit echolocation clicks that resemble creaking of rusty door hinges, frequency 20-170 kHz.
American scientists recorded 17 communicative signals in adult bottlenose dolphins, and only 6 in calves.
Obviously, the signal system becomes more complex with the age and individual experience of the animal. Of this number, 5 signals turned out to be common for bottlenose dolphins, pilot whales and white drums.
Bottlenose dolphins, like all cetaceans, sleep at the surface of the water, usually at night, and during the day only after feeding, periodically opening their eyelids for 1-2 seconds and closing them for 15-30 seconds. A weak blow from the hanging tail from time to time forces the sleeping animal out of the water for another respiratory act.
In sleeping dolphins, one hemisphere sleeps alternately, while the other is awake at this time.
Features of behavior
Dolphin speech
Dolphins are capable of producing a wide range of sounds using the nasal air sac located under the blowhole. There are roughly three categories of sounds: frequency-modulated whistles, explosive pulse sounds, and clicks. Clicks are the loudest sounds made by marine life.
Dolphins have a sound signaling system. Signals of two types: echolocation (sonar), serve animals to explore the situation, detect obstacles, prey, and “chirps” or “whistles”, for communication with relatives, also expressing emotional condition dolphin
The signals are emitted at very high, ultrasonic frequencies that are inaccessible to human hearing. The sound perception of people is in the frequency band up to 20 kHz, dolphins use a frequency of up to 200 kHz.
Scientists have already counted 186 different “whistles” in the “speech” of dolphins. They have approximately the same levels of organization of sounds as a person: six, that is, sound, syllable, word, phrase, paragraph, context, they have their own dialects.
In 2006, a team of British researchers from the University of St. Andrews conducted a series of experiments, the results of which suggest that dolphins are capable of assigning and recognizing names.
Communication with dolphins has a positive effect on the human body, especially on the child’s psyche. British experts came to this conclusion back in 1978. Since that time, the development of “dolphin therapy” began. It is now used to treat many physical and mental illness, including autism, and other ailments. Swimming with dolphins relieves chronic pain, improves immunity and even helps children develop speech.
An incredibly romantic fact from the “personal” life of dolphins - ethologists studying Amazon dolphins discovered that males give gifts to potential partners. So, what gift is waiting for a female dolphin to consider as a candidate for procreation? Of course, a bouquet of river algae!
India has become the 4th country to ban the keeping of dolphins in captivity. Previously, similar measures were taken by Costa Rica, Hungary and Chile. Indians call dolphins "a person or person of other origin than" homo sapiens
Dolphins not only have " lexicon"up to 14,000 sound signals, which allows them to communicate with each other, but also have self-awareness, "social consciousness" and emotional empathy - a willingness to help newborns and the sick, pushing them to the surface of the water.
Dolphins are famous for their playful behavior and the fact that, for fun, they can blow air bubbles underwater in the form of a ring using a blowhole. These may be large clouds of bubbles, streams of bubbles, or individual bubbles. Some of them act as a kind of communication signals.
Within a school, dolphins form very close bonds. Scientists have noticed that dolphins care for sick, wounded and elderly relatives, and a female dolphin can help another female during a difficult birth. At this time, the dolphins nearby, protecting the female in labor, swim around her for protection.
Another proof of the high intelligence of dolphins is the fact that adults sometimes teach their young to use special tools for hunting. For example, they “dress” sea sponges on their muzzles in order to avoid injury when hunting fish that can hide in bottom sediments of sand and sharp pebbles.
The oldest dolphin in captivity was named Nellie.
She lived at Marineland (Florida) and died when she was 61 years old.
Reproduction
When dolphins hunt, they use interesting tactics to drive fish into a trap.
They begin to circle around the school of fish, closing the ring, forcing the fish to form a tight ball. Then, one by one, the dolphins snatch the fish from the center of the school, preventing it from leaving.
The female dolphin carries the calf for ten months. It is born half the length of its mother's body. Like a baby whale, when sucking a baby dolphin's lips are replaced by a tongue rolled into a tube: it covers the mother's nipple with it, and she splashes milk into his mouth. All this happens under water: the respiratory canal of cetaceans is separated from the esophagus, and a dolphin, like whales, can swallow food under water without fear of choking. Dolphins give birth to one calf every two years. Three years later he becomes an adult. Dolphins live up to 25-30 years.