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Fox find me a group of sharks. Sea fox: not an animal, but a fish. Reproduction and lifespan


frilled shark
The frilled shark (Chlamydoselachus anguineus) is the only deep-sea shark in its family. The maximum length is 2 m. It bears offspring for about three and a half years.

The frilled shark is a rare and unusual shark species. The maximum length is not more than two meters. The body of a shark is serpentine. The anal, dorsal and two ventral fins are closer to the tail. Which makes her look more like an eel than a shark. She hunts on the same principle as a snake. First, it bends and quickly straightens in a jerk. And these are not all its unique features. Up to three dozen rows of small and very sharp teeth will not release the victim. Even if she manages to escape, she will receive numerous lacerations. The frilled shark hunts for small cephalopods and small sharks. This shark, unlike its relatives, does not tear the victim to pieces, but absorbs it entirely. Capable of swallowing fish half the length of its body. It lives at a depth of up to 1.5 thousand meters, but most often it can be found at a depth of about 200 meters.

The frilled shark got its name for the skin folds around the head, of which there are 6 on each side. They were formed by gill fibers, which cover the gills. The shark is able to cover its gills to create pressure inside the mouth, which helps to swallow food. The average length of these sharks is about one and a half meters. The largest specimen that is known to science reached a length of 2 meters.

The frilled shark's pregnancy lasts 3.5 years. This is the longest pregnancy among all vertebrates known to science. In one month, the embryo grows an average of 1–1.5 cm. At three months, the embryo has a fully formed jaw, fins and external gills, but it will stay in the womb for more than 3 years. Newborns are about 50 cm long. The frilled shark gives birth to an average of 10–15 pups.

The frilled shark is not of particular value to humans, unlike other marine life. But often comes across in the nets of fishermen and goes to food. This shark is considered a rare species due to its small number. Does not save the species and deep-sea habitat.

Source

From

Pelagic megamouth shark
The pelagic megamouth shark (Megachasma pelagios) is the only species known to science today from the genus Megachasm. In addition, this is one of the three types of sharks whose diet includes plankton.

Science knows only three species of sharks that feed on plankton: giant whale sharks and pelagic largemouth sharks. The pelagic largemouth shark lives at different depths from 50 to 1,600 m. The species was discovered in 1976. Until now, it is the only instance of the family. According to 2014 data, only 60 individuals of this species were found. Habitat Atlantic, Pacific and Indian oceans.

The largest individual of the species was a female pelagic megamouth shark. Its length was 5.7 m. It got into fishing nets off the coast of Japan. Despite the fact that the female was released, she was later washed ashore already dead. Little is known about the life of these sharks. According to the structure of the teeth, which are quite small, awl-shaped and the study of the stomach of dead individuals, these sharks are filterers. Their diet includes krill and other small inhabitants of the oceans.

Since the body of this shark is rather weak, it leads a passive lifestyle. For hunting plankton, she has her own secrets. When the mouth opens, the upper jaw moves forward. Thus, opening the silvery edging of the mouth, which is a bait for plankton.

Source

From

Class: cartilaginous fish
order: carchariformes
family: gray sharks
genus: gray sharks
habitats
The gray reef shark is found almost throughout the Pacific and Indian Oceans, adhering to coral reefs, strong currents and depths up to 280 m.
Distinguishing properties
The average body length usually reaches 1.9–2 m, males are somewhat larger than females. The maximum mass of a gray shark caught is 33.7 kg. Color - various shades of gray, sometimes brownish and even bronze. The shape of the shark's body resembles a torpedo.
Lifestyle
This is a smart, cunning and fast animal with a phenomenal sense of smell and quick reactions, showing great interest in everything that moves. Gray sharks are active throughout the day, hunting mainly at night, gathering in small flocks of 5 to 20 individuals. Lives up to 25 years.
reproduction
During the mating season, gray reef sharks protect an individual area from other individuals of their species, the area of ​​​​which is about 4 km2. When a competitor appears, the animal first shows dissatisfaction, making sharp movements with its tail and distinctly arching its back. The gray reef shark is a viviparous species. Once a year, the female gives birth to 1-6 cubs.
Food and Enemies
The main prey is fish, mollusks and crustaceans, the favorite is octopuses and other cephalopods. There are practically no natural enemies. Only angry individuals of their own species or humans are dangerous.
Source

From

Class: cartilaginous fish
order: carchariformes
family: gray sharks
genus: gray sharks
The Malagash night shark (Carcharhinus melanopterus) lives in the tropical waters of the Indian and Pacific Oceans. Through the Suez Canal, the species entered the Mediterranean Sea. Tries to stick to the coastal zone and shallow water.
Distinguishing properties
The average body length is 1.5–1.8 m, and the weight is 45 kg. The shape of the body is torpedo-shaped and streamlined, the head is slightly flattened. A distinctive feature of the species is the black end of the first dorsal fin.
The tip of the second dorsal and anal fins may also be black. The upper part of the body is grayish-brown, the bottom is white.
Lifestyle
Night predator. Prefers to stay in small groups, never forms large flocks.
There have been cases of attacks on people, but no deaths. Can easily exist in fresh or slightly brackish water. These large marine predators are tied to the same habitats. The average life expectancy is 30 years.
The basis of the predator's diet is fish, crustaceans and molluscs.
The main enemies of sharks are toothed whales.
reproduction
Sexual maturity occurs when the body size reaches 95–97 cm. The mating season lasts from November to March. During the courtship period, the male not only actively pursues the female, but also strikes her in the area of ​​​​the fins, and the wounds completely heal only after 4–6 weeks. Pregnancy lasts according to various sources from 7 to 16 months. Shark is a viviparous fish. At the same time, 2–3 sharks 2–4 cm long are born. Cubs are born every two years. Babies grow quickly, adding up to 23 cm annually.
Source

From

Class: cartilaginous fish
squad: stingrays
family: diamond
genus: rhomboid rays
habitats
The sea fox, or spiny stingray, is most common along the eastern coast of the Atlantic Ocean. The expanses of water from Norway to Namibia are the places of accumulation of the world population of these rays. The species is found in the Mediterranean and Black Seas, off the coast of South Africa and Madagascar.
What does a sea fox look like?
The female sea fox can reach a length of 120 cm, the male is somewhat smaller - the maximum length of his body is 70 cm. The shape of the body resembles a rhombus. The upper side of the body of the sea fox is covered with numerous spines, it is rough and colored in brownish tones with a pattern of dark and light spots. The long and thin tail is also covered with spikes. The underside of the body is light and smooth. The color of the skin is variable - it strongly depends on the habitat of the stingray.
Lifestyle and nutrition
The main habitat of the species is the sea muddy bottom. Stingrays live at depths of 20–300 m and deeper. In summer they come quite close to the coastline, and in winter they migrate to the depths.

It feeds on benthic crustaceans, sometimes small fish.
The danger is represented by various predatory fish, however, stingrays are able to defend themselves and are perfectly adapted to survive in the aquatic environment.
reproduction

The sea fox, like other stingrays, reproduces by egg production. After mating, the female begins to lay eggs - up to 170 during the year. Each egg is enclosed in a dense protective capsule, which has special processes and threads on the sides, with the help of which the female attaches the eggs to the algae. In the corner of each egg egg there is a small hole for oxygen, so that the fry can breathe. After 5 months, miniature rays are born - each no more than 12 cm in length. Having reached 15–17 cm in length, a teenager is able to hunt on his own.
Source

Waters though prefer cool temperatures. They are found both in the open ocean at a depth of up to 550 m, and near the coast, and usually stay in the surface layers of water. Thresher sharks make seasonal migrations and spend their summers at lower latitudes.

The diet mainly consists of schooling pelagic fish. Thresher sharks hunt using their long tail like a whip. They shoot down, drive and stun their prey, this explains their English name English. Thresher shark, which literally translates as "thresher shark". These are powerful and fast predators, able to completely jump out of the water. Their circulatory system is modified in such a way as to store metabolic heat energy and heat the body above the temperature of the surrounding water. Reproduction occurs by placental live birth. There are up to 4 newborns in a litter.

Despite their large size, fox sharks are not thought to pose a threat to humans because they are shy and have small teeth. This species is an object of commercial fishing and sport fishing. Their meat and fins are highly valued. The low reproductive rate makes sea foxes very susceptible to overfishing.

Taxonomy

Megachasmidae



Alopiidae

Alopias vulpinus




undescribed view Alopias sp.










The species was first scientifically described as Squalus vulpinus in 1788 by the French naturalist Pierre Joseph Bonnaterre. In 1810, Constantin Samuel Rafinesque described Alopias macrourus based on a specimen caught off the coast of Sicily. Later authors recognized the existence of a separate genus of fox sharks and synonymized Alopias macrourus and Squalus vulpinus. Thus, the scientific name of the fox shark became Alopias vulpinus .

The generic and specific names are derived respectively from the words of the Greek. ἀλώπηξ and lat. vulpes, each of which means "fox". In older sources, this species is sometimes called Alopias vulpes .

Morphological and allozyme analyzes have identified the thresher shark as a basal member of the clade, which also includes the bigeye and pelagic thresher sharks. Possibility of the existence of a fourth, hitherto undescribed species belonging to the genus of fox sharks and most closely related Alopias vulpinus, was rejected after allozyme analysis conducted in 1995.

area

The range of common sea foxes covers temperate and tropical waters throughout the world. In the western Atlantic, they are distributed from Newfoundland to the Gulf of Mexico, although rarely seen off New England, and from Venezuela to Argentina. In the eastern Atlantic, they range from the North Sea and the British Isles to Ghana, including Madeira, the Azores and the Mediterranean, and from Angola to South Africa. In the Indo-Pacific region, fox sharks are found from Tanzania to India, the Maldives, off the coast of Japan, Korea, southeast China, Sumatra, the east coast of Australia and New Zealand. They are also found around numerous islands in the Pacific including New Caledonia, the Society Islands, Tabuaeran and Hawaii. In the Eastern Pacific, they have been recorded in coastal waters from British Columbia to Chile, including the Gulf of California.

Thresher sharks make seasonal migrations, moving to high latitudes following masses of warm water. In the Eastern Pacific, in late summer and early autumn, males make longer migrations compared to females, reaching Vancouver Island. Young sharks prefer to stay in natural nurseries. It is likely that separate populations with different life cycles exist in the eastern Pacific and the western Indian Ocean. There are no interoceanic migrations. In the northwestern Indian Ocean, from January to May, when offspring are born, there is territorial and vertical segregation by sex. Mitochondrial DNA analysis has revealed significant regional genetic variation in thresher sharks found in different oceans. This fact confirms the hypothesis that sharks from different habitats, despite migration, do not interbreed.

Despite the fact that thresher sharks are sometimes seen in the coastal zone, they mainly lead a pelagic lifestyle and prefer to stay in the open sea, descending to a depth of 550 m. Young sharks can often be found in shallow water close to the coast.

Description

A characteristic feature of fox sharks is the strongly elongated upper lobe of the caudal fin, the length of which can be equal to the length of the body. Common sea foxes are active predators; with the help of a tail, they are able to stun the victim. They have a strong, torpedo-shaped body and a short, broad head with a conical, pointed snout. There are 5 pairs of short gill slits, with the last two slits located above the long and narrow pectoral fins. The mouth is small, curved in the form of an arch. There are 32-53 upper and 25-50 lower dentitions in the mouth. Teeth small, without serrations. The eyes are small. The third eyelid is missing.
The long, sickle-shaped pectoral fins taper to narrow, pointed tips. The first dorsal fin is quite high and is located closer to the base of the pectoral fins. The pelvic fins are about the same size as the first dorsal fin, and the males have thin, long pterygopodia. The second dorsal and anal fins are tiny. There are dorsal and ventral notches in the shape of a crescent in front of the caudal fin. A small ventral notch is located at the edge of the upper lobe. The lower lobe is short but well developed.

The skin of fox sharks is covered with small, overlapping placoid scales, each of which bears 3 ridges. The posterior edge of the scales ends with 3-5 marginal teeth. The coloration of the dorsal surface of the body is from metallic lilac-brown to gray, the sides are bluish, the belly is white. The white coloration extends to the base of the pectoral and ventral fins, which distinguishes thresher sharks from similar pelagic threshers, which lack spots at the base of the fins. Possible white edging on the tips of the pectoral fins.

Common sea foxes are the largest representative of the family, they reach a length of 7.6 m and a mass of 510 kg.

Biology

Food

97% of the sea fox's diet consists of bony fish, mostly small and schooling fish such as bluefish, mackerel, herring, garfish and glowing anchovies. Before attacking, the sharks circle around the school and compact it with tail strokes. Sometimes they hunt in pairs or small groups. In addition, large solitary fish, such as sawtooth, as well as squid and other pelagic invertebrates, can become their prey. Off the coast of California, they prey mainly on the California anchovy. Engraulis mordax, Oregon hake Merluccius productus, Peruvian sardine, Japanese mackerel, squid Loligo opalescens and crab Pleuroncodes planipes. During the period of the cold oceanographic regime, the composition of their diet is poorer, while during periods of warming, the spectrum of food expands.

There are numerous reports of fox sharks using the upper lobe of their caudal fin to silence their prey. Repeated cases have been recorded when, when making a blow, they hooked their tail on the longline. In July 1914, Russell J. Coles witnessed a sea fox flicking its tail into its mouth, and if it missed, the fish flew a considerable distance. On April 14, 1923, oceanographer W. E. Allen, standing on the pier, heard a loud splash nearby and saw a swirl of water 100 meters away, which a diving sea lion could produce. A moment later, a meter-long flat tail rose above the surface of the water. Next, the scientist watched as fox sharks pursued California slaty Atherinopsis californiensis. Having overtaken the prey, she whipped it with her tail, as if with a coachman's whip, and severely injured her. In the winter of 1865, Irish ichthyologist Harry Blake-Knox observed how, in Dublin Bay, a sea fox whipped a wounded loon (possibly a black-billed loon) with its tail, which it then swallowed. Subsequently, the validity of the Blake-Knox report has been questioned on the grounds that the thresher shark's tail is not stiff or muscular enough to deliver such a blow.

Life cycle

Thresher sharks reproduce by ovoviviparity. Mating occurs in the summer, usually in July and August, and childbirth takes place from March to June. Pregnancy lasts 9 months. Fertilization and development of embryos occurs in utero. After the yolk sac is empty, the embryo begins to feed on unfertilized eggs (intrauterine oophagia). The teeth of the embryos are peg-shaped and non-functional because they are covered with soft tissue. As they develop, they become more and more similar in shape to the teeth of adult sharks and "erupt" shortly before birth. In the Eastern Pacific, litter numbers range from 2 to 4 (rarely 6) newborns, and in the Eastern Atlantic, from 3 to 7.

The length of newborns is 114-160 cm and directly depends on the size of the mother. Young sharks add 50 cm per year, while adults grow only 10 cm. The age at which puberty is reached depends on the habitat. In the Pacific Northeast, males mature at a length of 3.3 m, which corresponds to an age of 5 years, and females at a length of 2.6-4.5, which corresponds to an age of 7 years. Life expectancy is at least 15 years, and the maximum period is about 45-50 years.

Human interaction

Despite their large size, sea foxes are not considered to be dangerous. They are shy and immediately swim away when a person appears. Divers testify that they are difficult to approach. The International Shark Attack File records one thresher shark attacks on humans and 4 attacks on boats, probably by hooked sharks. There are unconfirmed reports of an attack on a harpooner off the coast of New Zealand.
Famous sports angler Frank Mandas in his book "Sportsfishing for Sharks" retelling an old story. One unfortunate fisherman leaned over the side of the boat to look at a large fish caught on his hook. At the same moment, he was decapitated by a blow from the tail of a five-meter fox shark. The body of the fisherman capsized in the boat, and the head fell into the water and could not be found. Most authors consider this story unreliable.

Sea foxes are commercially harvested in Japan, Spain, USA, Brazil, Uruguay, Mexico and Taiwan. They are taken by longlines, pelagic nets and gillnets. Meat, especially fins, is highly prized. It is consumed fresh, dried, salted and smoked. The skin is dressed, vitamins are produced from liver fat.

In the United States, commercial fishing for thresher sharks using floating gillnets on the South Carolina coast has been developed since 1977. The fishery was started by 10 vessels using large mesh nets. For 2 years, the fleet already consisted of 40 ships. The peak came in 1982, when 228 vessels caught 1,091 tons of fox sharks. After that, their numbers decreased sharply due to overfishing, and in the late 80s, production decreased to 300 tons, large individuals ceased to come across. In the United States, thresher sharks are still caught, with 80% of the catch being caught in the Pacific Ocean and 15% in the Atlantic. Thresher sharks continue to be caught most with gillnets off the coast of California and Oregon, although the more valuable swordfish are the main fish there. Xiphius gladius, and thresher sharks are caught as by-catch. A small number of these sharks are harvested in the Pacific Ocean using harpoons, fine mesh drift nets and longlines. In the Atlantic, thresher sharks are more commonly caught as bycatch in swordfish and tuna.

Due to their low fecundity, members of the thresher shark genus are highly susceptible to overfishing. Between 1986 and 2000, an analysis of pelagic longline catches showed an 80% decline in numbers of harbor seal and bigeye shark in the northwest Atlantic.

Fox sharks are valued by sports anglers on a par with mako sharks. They are caught on a bait with a multiplier reel. Bait is used as bait.

Since the 1990s, there has been a restriction on the production of fox sharks in the United States. It is against the law to cut off the fins of live sharks by throwing the carcass overboard. There is a ban on the use of drift nets in the Mediterranean, but poachers illegally use such nets up to 1.6 km long when fishing for swordfish. The International Union for Conservation of Nature has given this species Vulnerable status.

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Notes

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Links

  • akyla.info/vidy_lis/4.html
  • View in the World Register of Marine Species ( World Register of Marine Species) (English)

An excerpt characterizing the Common sea fox

But despite the fact that that evening Natasha, now agitated, now frightened, with stopping eyes, lay for a long time in her mother's bed. Now she told her how he praised her, then how he said that he would go abroad, then how he asked where they would live this summer, then how he asked her about Boris.
“But this, this… has never happened to me!” she said. “Only I’m scared around him, I’m always scared around him, what does that mean?” So it's real, right? Mom, are you sleeping?
“No, my soul, I myself am afraid,” answered the mother. - Go.
“I won’t sleep anyway. What's wrong with sleeping? Mommy, mommy, this has never happened to me! she said with astonishment and fear before the feeling that she was aware of in herself. - And could we think! ...
It seemed to Natasha that even when she first saw Prince Andrei in Otradnoye, she fell in love with him. She seemed to be frightened by this strange, unexpected happiness that the one whom she had chosen back then (she was firmly convinced of this), that the same one had now met her again, and, as it seems, was not indifferent to her. “And it was necessary for him, now that we are here, to come to Petersburg on purpose. And we should have met at this ball. All this is fate. It is clear that this is fate, that all this was led to this. Even then, as soon as I saw him, I felt something special.
What else did he tell you? What verses are these? Read it ... - thoughtfully said the mother, asking about the poems that Prince Andrei wrote in Natasha's album.
- Mom, is it not a shame that he is a widower?
- That's it, Natasha. Pray to God. Les Marieiages se font dans les cieux. [Marriages are made in heaven.]
“Darling, mother, how I love you, how good it is for me!” Natasha shouted, crying tears of happiness and excitement and hugging her mother.
At the same time, Prince Andrei was sitting with Pierre and telling him about his love for Natasha and about his firm intention to marry her.

On that day, Countess Elena Vasilievna had a reception, there was a French envoy, there was a prince, who had recently become a frequent visitor to the countess's house, and many brilliant ladies and men. Pierre was downstairs, walked through the halls, and struck all the guests with his concentrated, absent-minded and gloomy look.
From the time of the ball, Pierre felt the approach of fits of hypochondria in himself and with a desperate effort tried to fight against them. From the time of the prince’s rapprochement with his wife, Pierre was unexpectedly granted a chamberlain, and from that time on he began to feel heaviness and shame in a large society, and more often the same gloomy thoughts about the futility of everything human began to come to him. At the same time, the feeling he noticed between Natasha, who was patronized by him, and Prince Andrei, his opposition between his position and the position of his friend, further strengthened this gloomy mood. He equally tried to avoid thoughts about his wife and about Natasha and Prince Andrei. Again everything seemed to him insignificant in comparison with eternity, again the question presented itself: “what for?”. And he forced himself day and night to work on the Masonic works, hoping to drive away the approach of the evil spirit. Pierre at 12 o'clock, leaving the countess's chambers, was sitting upstairs in a smoky, low room, in a worn dressing gown in front of the table and copying genuine Scottish acts, when someone entered his room. It was Prince Andrew.
“Ah, it’s you,” said Pierre with an absent-minded and displeased look. “But I’m working,” he said, pointing to a notebook with that kind of salvation from the hardships of life with which unhappy people look at their work.
Prince Andrei, with a beaming, enthusiastic face, renewed to life, stopped in front of Pierre and, not noticing his sad face, smiled at him with egoism of happiness.
“Well, my soul,” he said, “yesterday I wanted to tell you and today I came to you for this. Never experienced anything like it. I'm in love my friend.
Pierre suddenly sighed heavily and sank down with his heavy body on the sofa, next to Prince Andrei.
- To Natasha Rostov, right? - he said.
- Yes, yes, in whom? I would never believe it, but this feeling is stronger than me. Yesterday I suffered, suffered, but I will not give up this torment for anything in the world. I haven't lived before. Now only I live, but I can't live without her. But can she love me?... I'm old for her... What don't you say?...
- I? I? What did I tell you, - Pierre suddenly said, getting up and starting to walk around the room. “I always thought that… This girl is such a treasure, such… This is a rare girl… Dear friend, I beg you, don’t think, don’t hesitate, get married, get married and get married… And I’m sure that no one will be happier than you.
- But she!
- She loves you.
“Don’t talk nonsense ...” said Prince Andrei, smiling and looking into Pierre’s eyes.
“He loves, I know,” Pierre shouted angrily.
“No, listen,” said Prince Andrei, stopping him by the hand. Do you know what position I'm in? I need to tell everything to someone.
“Well, well, say, I’m very glad,” Pierre said, and indeed his face changed, the wrinkle smoothed out, and he joyfully listened to Prince Andrei. Prince Andrei seemed and was a completely different, new person. Where was his anguish, his contempt for life, his disappointment? Pierre was the only person before whom he dared to speak out; but on the other hand, he told him everything that was in his soul. Either he easily and boldly made plans for a long future, talked about how he could not sacrifice his happiness for the whim of his father, how he would force his father to agree to this marriage and love her or do without his consent, then he was surprised how on something strange, alien, independent of him, against the feeling that possessed him.
“I would not believe someone who would tell me that I can love like that,” said Prince Andrei. “It's not the same feeling I had before. The whole world is divided for me into two halves: one is she and there is all the happiness of hope, light; the other half - everything where it is not there, there is all despondency and darkness ...
“Darkness and gloom,” Pierre repeated, “yes, yes, I understand that.
“I can't help but love the light, it's not my fault. And I am very happy. You understand me? I know that you are happy for me.
“Yes, yes,” Pierre confirmed, looking at his friend with touching and sad eyes. The brighter the fate of Prince Andrei seemed to him, the darker his own seemed.

For marriage, the consent of the father was needed, and for this, the next day, Prince Andrei went to his father.
The father, with outward calm, but inward malice, received his son's message. He could not understand that someone wanted to change life, to bring something new into it, when life was already ending for him. “They would only let me live the way I want, and then they would do what they wanted,” the old man said to himself. With his son, however, he used the diplomacy he used on important occasions. Assuming a calm tone, he discussed the whole matter.
Firstly, the marriage was not brilliant in relation to kinship, wealth and nobility. Secondly, Prince Andrei was not the first youth and was in poor health (the old man especially leaned on this), and she was very young. Thirdly, there was a son whom it was a pity to give to a girl. Fourthly, finally, - said the father, looking mockingly at his son, - I ask you, put the matter aside for a year, go abroad, take medical treatment, find, as you like, a German, for Prince Nikolai, and then, if it’s love, passion, stubbornness, whatever you want, so great, then get married.
“And this is my last word, you know, the last ...” the prince finished in such a tone that he showed that nothing would make him change his mind.
Prince Andrei clearly saw that the old man hoped that the feeling of his or his future bride would not stand the test of the year, or that he himself, the old prince, would die by this time, and decided to fulfill his father's will: to propose and postpone the wedding for a year.
Three weeks after his last evening at the Rostovs, Prince Andrei returned to Petersburg.

The next day after her explanation with her mother, Natasha waited all day for Bolkonsky, but he did not arrive. The next day, the third day, it was the same. Pierre also did not come, and Natasha, not knowing that Prince Andrei had gone to her father, could not explain his absence to herself.
So three weeks passed. Natasha did not want to go anywhere, and like a shadow, idle and despondent, she walked around the rooms, in the evening she secretly cried from everyone and did not appear in the evenings to her mother. She was constantly blushing and irritated. It seemed to her that everyone knew about her disappointment, laughed and regretted her. With all the strength of inner grief, this vainglorious grief increased her misfortune.
One day she came to the countess, wanted to say something to her, and suddenly burst into tears. Her tears were the tears of an offended child who himself does not know why he is being punished.
The Countess began to reassure Natasha. Natasha, who at first listened to her mother's words, suddenly interrupted her:
- Stop it, mom, I don’t think, and I don’t want to think! So, I traveled and stopped, and stopped ...
Her voice trembled, she almost burst into tears, but she recovered herself and calmly continued: “And I don’t want to get married at all. And I'm afraid of him; I am now completely, completely, calmed down ...
The next day after this conversation, Natasha put on that old dress, which she was especially aware of for the cheerfulness it delivered in the morning, and in the morning she began her former way of life, from which she lagged behind after the ball. After drinking tea, she went to the hall, which she especially loved for its strong resonance, and began to sing her solfeji (singing exercises). Having finished the first lesson, she stopped in the middle of the hall and repeated one musical phrase that she especially liked. She listened joyfully to that (as if unexpected for her) charm with which these sounds, shimmering, filled the entire emptiness of the hall and slowly died away, and she suddenly became cheerful. “Why think about it so much and so well,” she said to herself, and began to walk up and down the hall, stepping not with simple steps on the resonant parquet, but at every step stepping from heel (she was wearing new, favorite shoes) to toe, and just as joyfully as to the sounds of his voice, listening to this measured clatter of heels and the creaking of socks. Passing by a mirror, she looked into it. - "Here I am!" as if the expression on her face at the sight of herself spoke. “Well, that's good. And I don't need anyone."
The footman wanted to come in to clean up something in the hall, but she did not let him in, again shutting the door behind him, and continued her walk. She returned that morning again to her beloved state of self-love and admiration for herself. - “What a charm this Natasha is!” she said again to herself in the words of some third, collective, masculine face. - "Good, voice, young, and she does not interfere with anyone, just leave her alone." But no matter how much they left her alone, she could no longer be at peace, and immediately felt it.
In the front door the entrance door opened, someone asked: are you at home? and someone's footsteps were heard. Natasha looked in the mirror, but she did not see herself. She listened to the sounds in the hallway. When she saw herself, her face was pale. It was he. She knew this for sure, although she barely heard the sound of his voice from the closed doors.
Natasha, pale and frightened, ran into the living room.
- Mom, Bolkonsky has arrived! - she said. - Mom, this is terrible, this is unbearable! “I don’t want to… suffer!” What should I do?…
The countess had not yet had time to answer her, when Prince Andrei entered the drawing room with an anxious and serious face. As soon as he saw Natasha, his face lit up. He kissed the hand of the countess and Natasha and sat down beside the sofa.
“For a long time we have not had pleasure ...” the countess began, but Prince Andrei interrupted her, answering her question and obviously in a hurry to say what he needed.
- I have not been with you all this time, because I was with my father: I needed to talk to him about a very important matter. I just got back last night,” he said, looking at Natasha. “I need to talk to you, Countess,” he added after a moment's silence.
The Countess sighed heavily and lowered her eyes.
“I am at your service,” she said.
Natasha knew that she had to leave, but she could not do it: something was squeezing her throat, and she looked impolitely, directly, with open eyes at Prince Andrei.
"Now? This minute!… No, it can't be!” she thought.
He looked at her again, and this look convinced her that she had not been mistaken. - Yes, now, this very minute her fate was being decided.
“Come, Natasha, I will call you,” said the countess in a whisper.
Natasha, with frightened, pleading eyes, looked at Prince Andrei and at her mother, and went out.
“I have come, Countess, to ask for the hand of your daughter,” said Prince Andrei. The countess's face flushed, but she said nothing.
“Your suggestion…” the Countess began sedately. He remained silent, looking into her eyes. - Your offer ... (she was embarrassed) we are pleased, and ... I accept your offer, I'm glad. And my husband ... I hope ... but it will depend on her ...
- I will tell her when I have your consent ... do you give it to me? - said Prince Andrew.
“Yes,” said the Countess, and held out her hand to him, and with a mixture of aloofness and tenderness pressed her lips to his forehead as he leaned over her hand. She wanted to love him like a son; but she felt that he was a stranger and a terrible person for her. “I'm sure my husband will agree,” said the countess, “but your father ...
- My father, to whom I informed my plans, made it an indispensable condition for consent that the wedding should not be earlier than a year. And this is what I wanted to tell you, - said Prince Andrei.
- It is true that Natasha is still young, but so long.
“It could not be otherwise,” Prince Andrei said with a sigh.
“I will send it to you,” said the countess, and left the room.
“Lord, have mercy on us,” she repeated, looking for her daughter. Sonya said that Natasha was in the bedroom. Natasha sat on her bed, pale, with dry eyes, looked at the icons and, quickly making the sign of the cross, whispered something. Seeing her mother, she jumped up and rushed to her.
- What? Mom?… What?
- Go, go to him. He asks for your hand, - said the countess coldly, as it seemed to Natasha ... - Go ... go, - the mother said with sadness and reproach after her daughter, who was running away, and sighed heavily.
Natasha did not remember how she entered the living room. When she entered the door and saw him, she stopped. “Is this stranger really become my everything now?” she asked herself and instantly answered: “Yes, everything: he alone is now dearer to me than everything in the world.” Prince Andrei went up to her, lowering his eyes.
“I fell in love with you from the moment I saw you. Can I hope?
He looked at her, and the earnest passion of her countenance struck him. Her face said: “Why ask? Why doubt that which is impossible not to know? Why talk when you can’t express what you feel in words.
She approached him and stopped. He took her hand and kissed it.
– Do you love me?
“Yes, yes,” Natasha said as if with annoyance, sighed loudly, another time, more and more often, and sobbed.
– About what? What's wrong with you?
“Oh, I’m so happy,” she answered, smiled through her tears, leaned closer to him, thought for a second, as if asking herself if it was possible, and kissed him.
Prince Andrei held her hands, looked into her eyes, and did not find in his soul the former love for her. Something suddenly turned in his soul: there was no former poetic and mysterious charm of desire, but there was pity for her feminine and childish weakness, there was fear of her devotion and gullibility, a heavy and at the same time joyful consciousness of the duty that forever connected him with her. The real feeling, although it was not as light and poetic as the former, was more serious and stronger.
“Did maman tell you that it couldn’t be before a year?” - said Prince Andrei, continuing to look into her eyes. “Is it really me, that child girl (everyone said so about me) thought Natasha, is it possible that from now on I am a wife, equal to this strange, sweet, intelligent person, respected even by my father. Is that really true! Is it really true that now it is no longer possible to joke with life, now I am big, now responsibility for all my deeds and words lies on me? Yes, what did he ask me?
“No,” she answered, but she did not understand what he was asking.
“Forgive me,” said Prince Andrei, “but you are so young, and I have already experienced so much life. I'm scared for you. You don't know yourself.
Natasha listened with concentrated attention, trying to understand the meaning of his words, but did not understand.
“No matter how hard this year will be for me, postponing my happiness,” continued Prince Andrei, “during this period you will believe yourself. I ask you to make my happiness in a year; but you are free: our engagement will remain a secret, and if you are convinced that you do not love me, or would love ... - said Prince Andrei with an unnatural smile.
Why are you saying this? Natasha interrupted him. “You know that from the very day you first came to Otradnoye, I fell in love with you,” she said, firmly convinced that she was telling the truth.
- In a year you will recognize yourself ...
- A whole year! - Natasha suddenly said, now only realizing that the wedding was postponed for a year. - Why is it a year? Why a year? ... - Prince Andrei began to explain to her the reasons for this delay. Natasha didn't listen to him.
- And it can not be otherwise? she asked. Prince Andrei did not answer, but his face expressed the impossibility of changing this decision.
- This is terrible! No, it's terrible, terrible! Natasha suddenly spoke up and sobbed again. “I’ll die waiting for a year: it’s impossible, it’s terrible. - She looked into the face of her fiancé and saw on him an expression of compassion and bewilderment.
“No, no, I’ll do everything,” she said, suddenly stopping her tears, “I’m so happy!” The father and mother entered the room and blessed the bride and groom.
From that day on, Prince Andrei began to go to the Rostovs as a groom.

There was no betrothal, and no one was announced about Bolkonsky's engagement to Natasha; Prince Andrew insisted on this. He said that since he was the cause of the delay, he must bear the full burden of it. He said that he had forever bound himself with his word, but that he did not want to bind Natasha and gave her complete freedom. If in six months she feels that she does not love him, she will be in her own right if she refuses him. It goes without saying that neither the parents nor Natasha wanted to hear about it; but Prince Andrei insisted on his own. Prince Andrei visited the Rostovs every day, but not like a groom treated Natasha: he told her you and only kissed her hand. Between Prince Andrei and Natasha, after the day of the proposal, completely different than before, close, simple relations were established. They didn't seem to know each other until now. Both he and she loved to remember how they looked at each other when they were still nothing, now they both felt like completely different beings: then pretended, now simple and sincere. At first, the family felt awkward in dealing with Prince Andrei; he seemed like a man from an alien world, and Natasha for a long time accustomed her family to Prince Andrei and proudly assured everyone that he only seemed so special, and that he was the same as everyone else, and that she was not afraid of him and that no one should be afraid his. After a few days, the family got used to him and did not hesitate to lead the old way of life with him, in which he took part. He knew how to talk about housekeeping with the count, and about outfits with the countess and Natasha, and about albums and canvases with Sonya. Sometimes the household Rostovs among themselves and under Prince Andrei were surprised at how all this happened and how obvious the omens of this were: both the arrival of Prince Andrei in Otradnoye, and their arrival in Petersburg, and the similarity between Natasha and Prince Andrei, which the nanny noticed on the first visit Prince Andrei, and the clash in 1805 between Andrei and Nikolai, and many other omens of what happened, were noticed at home.
The house was dominated by that poetic boredom and silence that always accompanies the presence of the bride and groom. Often sitting together, everyone was silent. Sometimes they got up and left, and the bride and groom, remaining alone, were also silent. Rarely did they talk about their future lives. Prince Andrei was scared and ashamed to talk about it. Natasha shared this feeling, like all his feelings, which she constantly guessed. Once Natasha began to ask about his son. Prince Andrei blushed, which often happened to him now and that Natasha especially loved, and said that his son would not live with them.
- From what? Natasha said scared.
“I can’t take him away from my grandfather and then…”
How I would love him! - said Natasha, immediately guessing his thought; but I know you want no pretexts to accuse you and me.
The old count sometimes approached Prince Andrei, kissed him, asked him for advice on the upbringing of Petya or the service of Nikolai. The old countess sighed as she looked at them. Sonya was afraid at any moment to be superfluous and tried to find excuses to leave them alone when they did not need it. When Prince Andrei spoke (he spoke very well), Natasha listened to him with pride; when she spoke, she noticed with fear and joy that he was looking at her attentively and searchingly. She asked herself in bewilderment: “What is he looking for in me? What is he trying to achieve with his eyes? What, if not in me what he is looking for with this look? Sometimes she entered into her insanely cheerful mood, and then she especially liked to listen and watch how Prince Andrei laughed. He rarely laughed, but when he did, he gave himself over to his laughter, and every time after that laughter she felt closer to him. Natasha would have been perfectly happy if the thought of the upcoming and approaching parting had not frightened her, since he, too, turned pale and cold at the mere thought of it.
On the eve of his departure from Petersburg, Prince Andrei brought with him Pierre, who had never been to the Rostovs since the ball. Pierre seemed confused and embarrassed. He was talking to his mother. Natasha sat down with Sonya at the chess table, thus inviting Prince Andrei to her. He approached them.
"You've known the Earless for a long time, haven't you?" - he asked. - Do you love him?
- Yes, he is nice, but very funny.
And she, as always talking about Pierre, began to tell jokes about his absent-mindedness, jokes that they even made up about him.
“You know, I confided our secret to him,” said Prince Andrei. “I have known him since childhood. This is a heart of gold. I beg you, Natalie,” he said suddenly seriously; I'm leaving, God knows what might happen. You can spill... Well, I know I shouldn't talk about it. One thing - whatever happens to you when I'm gone...
– What will happen?…
“Whatever the grief,” continued Prince Andrei, “I ask you, m lle Sophie, no matter what happens, turn to him alone for advice and help. This is the most absent-minded and funny person, but the most golden heart.
Neither father and mother, nor Sonya, nor Prince Andrei himself could foresee how parting with her fiancé would affect Natasha. Red and agitated, with dry eyes, she walked around the house that day, doing the most insignificant things, as if not understanding what awaited her. She did not cry even at the moment when he said goodbye, he kissed her hand for the last time. - Don't leave! she only said to him in a voice that made him wonder if he really needed to stay and which he remembered for a long time after that. When he left, she didn't cry either; but for several days she sat in her room without crying, was not interested in anything, and only occasionally said: “Ah, why did he leave!”
But two weeks after his departure, just as unexpectedly for those around her, she woke up from her moral illness, became the same as before, but only with a changed moral physiognomy, like children with a different face get out of bed after a long illness.

The health and character of Prince Nikolai Andreevich Bolkonsky, in this last year after the departure of his son, became very weak. He became even more irritable than before, and all the outbursts of his causeless anger for the most part fell upon Princess Mary. It was as if he diligently sought out all her sore spots in order to torture her morally as cruelly as possible. Princess Marya had two passions and therefore two joys: her nephew Nikolushka and religion, both of which were the prince's favorite themes of attacks and ridicule. Whatever they talked about, he reduced the conversation to the superstitions of old girls or to pampering and spoiling children. - “You want to make him (Nikolenka) the same old girl as you yourself; in vain: Prince Andrei needs a son, not a girl, ”he said. Or, turning to mademoiselle Bourime, he asked her in front of Princess Mary how she liked our priests and images, and joked ...

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shark fox(the second name is “sea fox”, the Latin name is “Alopias vulpinus”) is a species of sea sharks that belongs to the fox shark family, order Lamniformes.

signs
Sea foxes are large sharks, with an average body length of 3 meters, specimens up to 5 meters long are known. The upper part of the body is painted in a dark gray-blue color, the belly is white. The average weight of fox sharks is 300 kilograms (maximum weight is 500 kilograms).

Distinctive sign sea ​​foxes is their caudal fin, the upper lobe of which is incredibly large, sometimes exceeding the length of the body of the fish itself. Such a tail is necessary for fish to hunt. Ichthyologists say that the sea fox is able to stun flocks of fish and even birds and small marine mammals with its tail ladle. In search of food, the shark rises to the surface of the water and, seeing potential food, strongly strikes the sea surface with its caudal fin.

Habitat

Fox sharks inhabit the basins of the Pacific and Atlantic oceans. They prefer to stay in tropical waters, but often swim in the waters of temperate latitudes.

Danger!!!

This type of shark does not pose a great danger to humans. However, cases of attacks of these sharks on people are described. Sea foxes usually hunt collectively, that is, they gather in groups of 3 to 5 individuals and surround schools of fish, drown them out with their tails, and then all together rush to the center of the accumulation of fish. It is during the moments of collective hunting that fox sharks are most dangerous. During the chase, they rush after any moving object in the water.

Class - Cartilaginous fishes / subclass - Elasmobranchii fishes / Superorder - Sharks (Selach)

Storystudy

The largest sea fox (Alopias vulpinus), its size is 5.5-6 meters, can be found in coastal areas. The smallest pelagic fox shark (Alopias pelagicus) is about 3 meters in size and lives at depths away from the coast. The color is a beautiful dark blue with a whitish belly. It has flat wide pectoral fins. The eyes are larger than those of the common fox, but not the same as those of the big-eyed fox. The most "beautiful" big-eyed fox shark (Alopias superciliosus) has unnaturally large bulging eyes. And what unites all representatives of this family is the possession of a magnificent fox tail.

Spreading

These sharks can be found near California and in parts of the Indian and Pacific Oceans.

The pelagic fox shark (Alopias pelagicus) lives in the Pacific and Indian Oceans. It can also be found off the coast of China, Taiwan, Western Australia and many other countries.

Externalview

Adult thresher sharks measure about 4.7 meters and weigh about 360 kilograms. Outwardly, these sharks stand out with huge eyes, which is typical for individuals that live in dark places.

Structural features

The fox shark has a very long upper lobe of the caudal fin, reaching the length of the entire body.

reproduction

Fox sharks are viviparous. Adult females are capable of giving birth to no more than two sharks. Newborn individuals measure about 1.5 meters. With a body length of about 4 meters, fox sharks reach sexual maturity.

Lifestyle

When hunting, this shark uses its long tail as its main weapon. Approaching a school of fish, the sea fox begins to circle around it, foaming the water with whip-like strokes of the caudal fin. Gradually, the circles become smaller and smaller, and the frightened fish gather in an increasingly compact group. It is then that the shark begins to greedily swallow its prey. A couple of sea foxes sometimes participate in such a hunt. In some cases, the sea fox acts like a flail with its tail fin, using it to stun its prey.


Food

The main food of fox sharks is small fish and shellfish. Thresher shark (Alopias vulpinus) has a fairly long upper tail fin. It has dimensions commensurate with the size of the body of a shark. The fox shark hunts with its fin. She wedges herself into a flock of fish and begins to beat her tail in different directions, stunning the fish. She then slowly eats her prey. Large individuals often attack even dolphins.

population

Fortunately, it has no commercial value, does not like to settle on the coast, has a formidable weapon and large size - all this helps it a lot not to get into the Red Book.


fox shark and man

Fox sharks are completely harmless to humans, however, during the dive of divers, they revolve around him, although they do not attack. However, there is information that these individuals attacked boats.

Genus: Alopias Rafinesque = Fox sharks, sea foxes

Species: Alopias vulpinus (Bonnaterre, 1788) = Sea fox

Sea fox = Alopias vulpinus

The sea fox (Thresher Shark) was first described by Bonnaterre in 1788 as Squalus vulpinis and later changed to the current name: Alopias vulpinus (Bonaterre, 1788). The word Vulpinus is derived from "fox" - in Latin vulpes.

Synonymous names include Squalus vulpes Gmelin 1789, Alopias macrourus Rafinesque 1810, Galeus vulpecula Rafinesque 1810, Alopias caudatus Philipps 1932, Alopas greyi Whitely 1937 and others.

It is also called: Fox Shark, Sea Fox, Common thresher, Fish shark, Fox shark, Longtail shark, Sea fox, Swingtail, Swiveltail, Thresher, Thresher shark, Whiptail shark

The common sea fox is widespread in all oceans, mainly in the temperate and subtropical zones. In the warm season, this shark migrates to the seas of the temperate zone. In the Atlantic Ocean, for example, it reaches the Gulf of St. Lawrence and the Lofoten Islands (Northern Norway) in summer.

In the western Atlantic, it is found from Newfoundland to Cuba and from southern Brazil to Argentina. In the eastern Atlantic from Norway and the British Isles to Ghana and the Ivory Coast, including the Mediterranean Sea.

In the Indo-Pacific region, it is found in the waters of South Africa, Tanzania, Somalia, the Maldives, the Chagos Archipelago, the Gulf of Aden, Pakistan, India, Sri Lanka, Sumatra, Japan, the Republic of Korea, Australia, New Zealand, and New Caledonia. The shark is also found in the Islands of Oceania, the Hawaiian Islands, and in the eastern Pacific region - from the coast of British Columbia through central California and Panama south to Chile.

The common sea fox lives in tropical and temperate waters, and is found both in the open ocean and near the coast. It usually stays in the surface layers of water, sometimes making jumps above the surface.

The sea fox prefers cool sea water, but can also wander in cold coastal areas. It can, if necessary, dive to a depth of 350 m.

The sea fox is a typical pelagic shark. The common sea fox reaches 5-6 m in length. The maximum recorded length is 760 cm. Adult sea foxes weigh between 200-350 kg. The maximum weight is about 450 kg. It has small jaws but can use its tail to drive and even kill fish. Their tail keel has a very elongated upper lobe. The pectoral fins are crescent-shaped, narrow and curved. Like other sharks, it has an anal fin, 5 gill slits, 2 dorsal fins without any internal skeleton, a mouth behind the eyes, and eyes without nictitating eyelids.

The sea fox has few, blade-like, smooth, crooked teeth. There are 20 teeth on both sides of the upper jaw and 21 teeth on both sides of the lower jaw. The teeth from a specimen caught off the coast of Massachusetts were almost 13 feet long.

The body of a common sea fox with a brown, gray or black back and a light belly, but there are dark spots near the pelvic fin and the beginning of the tail. The sides of the body are above the base of the pectoral fins with a white patch that extends forward from the ventral region.

Large sharks attack young sea foxes, but adults have no known predators. The sea fox lives for 20 years or more.

The usual food of the sea fox is various schooling fish, which it devours in large numbers.

Bony fish make up 97% of the sea fox's diet. Blue fish and butterfish are the most common food. They also feed on mackerel, herring, mackerel and other species.

The teeth are small, but strong and sharp, they are able to grab not only a variety of fish, but also squid, octopus, crab, and even seabirds.

By way of life, the sea fox is a pelagic, highly migratory species, leading a nocturnal lifestyle. She is a marine species, inhabiting both coastal and ocean water. It is most commonly observed far from the coast, despite the fact that it often cruises close to the coast in search of food. Adults are common over the continental shelf, while juveniles live in coastal bays and near the water's edge.

The sea fox uses its long tail as its main weapon when hunting. Approaching a school of fish, the sea fox begins to circle around it, foaming the water with whip-like strokes of the caudal fin. Gradually, the circles become smaller and smaller, and the frightened fish gather in an increasingly compact group. It is then that the shark begins to greedily swallow its prey. A couple of sea foxes sometimes participate in such a hunt.

In some cases, the sea fox acts like a flail with its tail fin, using it to stun its prey. Such a victim is not always fish. In particular, a shark was observed attacking seabirds sitting on the surface of the water in this way. An accurate blow with the tail - and the unfolded shark grabs its not quite ordinary prey.

In the stomach of one specimen, about 4 m long, for example, 27 large mackerels were found.

They are very strong swimmers, so they can jump almost entirely out of the water.

Reproduction occurs by ovoviviparity (there is no placenta in females), and the fecundity of this shark is very small - the female brings only two to four sharks, though very large ones. Their length at birth can reach 1.1 - 1.5 m, and weight between 5-6 kg.

The time of birth is confined to the warm summer season. Females give birth to up to 4-6 cubs. Sharks (more precisely, shark embryos) hatch from eggs while still inside the female. Developing embryos are ovophagi; they will eat the smaller, weaker baby shark embryos while they are in the womb.

On average, young sharks grow 50 cm per year, while adults grow about 10 cm.

Females become sexually mature with a body length of at least 2.6-3.5 m, males - 3.3 m.

Sea foxes are not aggressive and do not pose a threat to human life, but an attack can be provoked. Sharks are shy and difficult to approach. Divers who have encountered these sharks claim they did not act aggressively. Two provoked attacks by these sharks on boats with people are known. The sea fox's large tail can injure divers when attacked.

They have some commercial value, sometimes caught in the by-catch of tuna. Sea fox meat and fins are of good commercial quality. Their skins are used for skin, and the fat from their livers can be used to make a number of vitamins.

The total population of the sea fox is decreasing due to the depletion of fish stocks. Shark abundance in the American Atlantic water has decreased to about 67% of the previous abundance.

About the range, status and abundance of the sea fox in the Mediterranean Sea: Common or frequent species. Throughout the western Mediterranean as far as Sicily; somewhat rarer from southern Tunisia and more and more sporadic further east to Libya and Egypt. Sicilian and Maltese straits - sometimes local abundance. Cosmopolitan in the Ionian Sea, also on both sides of the Adriatic where the sea fox is found along the northern coasts; the coast of the Balkan Peninsula, the Aegean Sea, Turkey, the Dodecanese and Cyprus; a rarer species off the coast of Lebanon and Israel.

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