Type of spine in a tiger shark. The tiger shark is a thunderstorm of the tropical seas. Shark species, names and photos

Tiger shark- cartilaginous fish from the family of gray sharks, which is the most dangerous species of marine animals for humans.

This huge fish gray color lives in coastal waters and does not go deeper than 3 meters. Unfortunately, people from time to time encounter a formidable predator and it ends badly, even to the point of death.

But for a person it happens in exceptional cases, because a toothy fish prefers to swim at a depth of 350 meters. Sometimes the shark was noticed at a depth of 900 meters. Perhaps it goes even deeper, but this is not recorded anywhere.

Representatives of this species of gray sharks are found in all seas in temperate and tropical latitudes. predatory fish roams, swimming in warm waters from one side of the world to another. Easily crosses the Indian, Atlantic, and even the Pacific Ocean. Although the depth of the ocean does not frighten her, nevertheless the fish prefers to be closer to the continents.

The range covers areas such as northern regions Indian Ocean, Caribbean waters and Oceania. A large number are observed off the northwest African coast and near the island of Madagascar. coastal zone of the Australian continent and Persian Gulf for sharks of this species are very attractive. But where they do not swim is the Mediterranean Sea.

Appearance of a tiger shark

This species is the largest representative of its family that lives in the open sea. The body length of the shark is 3-4 meters with a weight of 400 to 600 kg.

Females are usually larger than males. Some female individuals reach a length of 5 meters, but as a rule, the length of the female does not exceed 4.5 meters. Some experts argue that the predator can grow to a size of 7.5 m, weighing 3 tons.

A large female was caught off the coast of Australia, whose weight reached 1200 kg and a length of 5.5 m. Cartilaginous fish with similar data were no longer found, apparently such a large specimen was an exceptional case.

The body of the fish has a gray tint. Young individuals have a skin of a greenish color along which dark stripes run, resembling a tiger color. From this predator and got its specific name. The stripes gradually disappear when the shark reaches 2 meters in length.

Such stripes are excellent at camouflaging young tiger sharks from larger enemies, including adults of their own species.

Adult fish have a uniform coloration of the upper body. The belly is light yellow or white. The large head is blunt wedge-shaped. Shark mouth very big size and armed with razor-sharp teeth. Teeth have characteristic appearance- Beveled top and serrated blade. With such teeth bloodthirsty predator easily tears through any flesh. The front part of the body has a thickened appearance and tapers towards the tail, which means it has excellent streamlining. Although, the readings of the speed that the fish can develop are not very high. Max Speed The movement of a shark in the water is 30 km/h.

The tiger shark is a real toothy monster.

reproduction

Puberty of predators is comparable to their size. For example, in males it occurs, with a body length of 2.3-2.5 m. To become sexually mature, females must grow 2.5-3 m long. These fish are viviparous.

Fertilization occurs 1 time in 3 years, pregnancy lasts 16 months. A shark can produce from 10 to 80 sharks at a time. Cubs have a length of 51 to 78 cm. Having been born, small tiger sharks immediately begin an independent life.

In the period before giving birth, the mother shark loses its appetite. This circumstance helps to avoid cannibalism. To protect their babies, female sharks huddle in flocks, as cubs are in danger everywhere, and above all, from male tiger sharks.

Survive in ocean depths not easy, however, those who are lucky grow into huge and ferocious predators. There is no exact data on the life expectancy of tiger sharks, but there is evidence that representatives of the species can live for more than 12 years.

Behavior and nutrition of the tiger shark

Predatory fish is omnivorous and is able to deal with everything that produces any movement. The diet of young individuals is made up of mollusks, fish and. When sharks grow up, their diet expands significantly. Their victims are not only fish, but also other types of sharks, seals, sea lions, dolphins and even birds sitting on the water. Sharks love to feast on carrion and garbage, which floats a lot in the coastal zone.

Tiger sharks have an excellent sense of smell. Smell spreads even better in water than in air, and a shark can smell blood from miles away. Much depends on where the undercurrent is directed.

In pursuit of prey, sharks often appear in close proximity to the coast and there is a high probability of a collision with a person. According to statistics for 2011, there were 169 tiger shark attacks on people around the world. 29 of them were fatal. It is very difficult to escape from a shark attack, given its huge strong jaws and sharp teeth.

In order to hunt, sharks never come together in packs. It is common for them to eat their smaller relative. Normally, sharks are rather slow. However, sensing the prey, the fish begins to move quickly and swiftly.

These predators do not have an air bladder and cannot hang in the water because of this. They have to be on the move all the time. The shark chooses caves or the seabed, where it can lie down to rest. Tiger sharks hunt mainly at night.

Brindle or leopard shark is the only representative of cartilaginous fish and belongs to the genus of the same name from the family of gray sharks of the order Carchariformes. This is one of the most common and numerous species of sharks currently living on our planet.

Description of the tiger shark

The tiger shark belongs to the oldest class, which arose several million years ago, but to this day appearance of this representative of cartilaginous fish practically did not undergo any significant changes.

Appearance

Range, habitats

The tiger shark can be found more often than other species in tropical as well as sub tropical waters. individuals different ages This predator is found not only in the waters of the open ocean, but also in close proximity to the coastline.

It is interesting! Sharks swim especially close to the coast and islands in the Caribbean Sea and the Gulf of Mexico, and also approach the shores of Senegal and New Guinea.

AT last years Increasingly, this species is found in the waters of Australia and near the island of Samoa. If necessary, to find food for themselves, tiger sharks can even swim into small bays and relatively shallow river channels. Often the "sea scavenger" is attracted to busy beaches with numerous vacationers, so this species of predator is also well known under the name man-eating shark.

Tiger shark diet

The tiger shark is an active predator and an excellent swimmer, slowly patrolling its territory for hunting. As soon as the prey is detected, the shark becomes fast and agile, instantly developing a sufficiently high speed. The tiger shark is very voracious and prefers to hunt alone, most often at night..

The basis of the diet is crabs, lobsters, bivalves and gastropods, squids, as well as the most various kinds fish, including rays and other, smaller species of sharks. Very often, various sea birds, snakes and mammals, represented by bottlenose dolphins, white-barreled dolphins and spotted dolphins, become prey. Tiger sharks attack dugongs and seals, as well as sea ​​lions.

Important! The shell of the animal is not a serious obstacle for the "sea scavenger", therefore the predator successfully hunts even the largest leatherback and green turtles, eating away their body with sufficiently powerful and strong jaws.

Large serrate teeth make it possible for a shark to attack large prey, but the basis of their diet is still represented by small animals and fish, the length of which does not exceed 20-25 cm. A very acute sense of smell allows the shark to quickly respond to even the slightest presence of blood, and the ability trap sound waves low frequency helps to confidently detect prey in murky waters.

It is interesting! For a tiger shark, cannibalism is characteristic, therefore, eating by large individuals of the smallest or weakest relatives is often observed, but this species does not disdain carrion or garbage.

Adults often attack an injured or sick whale and also feed on their carcasses. Every year in July, large schools of tiger sharks gather along the coast of the western part of the Hawaiian Islands, where chicks and young of dark-backed albatrosses begin their independent years. Insufficiently strong birds sink to the surface of the water and immediately become easy prey for predators.

Reproduction and offspring

Adult individuals living alone are able to unite in order to procreate. In the process of mating, the males dig their teeth into the dorsal fins of the females, as a result of which the eggs in the womb are fertilized. The gestation period lasts an average of 14-16 months.

Immediately before giving birth, females huddle together and avoid males. Among other things, in the process of childbirth, the females lose their appetite, which avoids the cannibalism characteristic of the species.

It is interesting! The tiger shark belongs to the category of ovoviviparous fish, so the offspring develops in the womb of the female in eggs, but when the time of birth approaches, the babies are released from the egg capsules.

This species is considered quite prolific, and this fact partly explains the significant number and very extensive range of the predator. As a rule, a female tiger shark at a time brings from two to five dozen cubs, whose body length reaches 40 cm or more. Females do not care about their offspring at all. Juveniles have to hide from adults so as not to become easy prey for them.

The tiger shark is in the "honorable" third place on the list of ten that it is highly undesirable for any of us to meet. The second name of this species is the leopard shark. In the system of fish, its place is determined as follows: the family of gray sharks (Carcharhinidae) in the order of carcharhiniformes (Carcharhiniformes) in the class of cartilaginous fish. The scientific Latin name for this shark is Galeocerdo cuvier.

The genus name is associated with Greek word"galeos" (γαλεός), which means "shark". And the name of the species "cuvier" - on behalf of the famous French naturalist, whose name is Georges Leopold Cuvier.

Distribution and other features of the tiger shark

The tiger shark, one of them, has a vast distribution area: almost the entire World Ocean in tropical and subtropical regions (both in the open ocean and off the coasts). central part Pacific Ocean- the place where these sharks are most often found. Active at night.

Appearance and name

The name "tiger shark" is associated with a characteristic color. In young individuals that have not reached a length of two meters, there are clearly visible dark transverse stripes on the sides, resembling a tiger pattern. AT young age the stripes serve as camouflage, disguising young sharks from larger relatives.

What does a tiger shark look like as an adult?

The coloration of the upper body of adults can be of varying intensity of gray shades with blurry darker gray spots. These are the remains of faded and faded stripes that adorned the sides and backs of young sharks.

The ventral side of the body of the tiger shark, like all pelagic species, is lighter than the dorsal side: off-white shades. Watch a video about a tiger shark:

It is believed that the name “tiger shark” captures its cruel nature, because it is one of the deadliest sharks in the oceans.

In the front part of the body of sharks of this species is thicker, narrows in the belly area, and rather thin in the tail part. Take a close look at the photo of the tiger shark and you will see these features of its structure.

This shark has a large head and large eyes. Due to the wedge shape, the head is very mobile, and the shark can easily turn it right and left without difficulty. The tiger shark has a blunt and short snout, with a huge mouth that has powerful and strong jaw muscles. In the video about the tiger shark, you can see its mouth.

Uniqueness of teeth

Of particular note is the teeth of this terrible predator, they are not like the teeth of other sharks. You can even admire them if you just look at the photo of a tiger shark - its teeth.

What are the features of the structure of teeth:

• the width of the base of the tooth is greater than its length (height);
• they are sharp and large, and the edges are roughly serrated;
• each notch has even smaller notches along the edges;
• the outer edge has an inward slope of about 45 degrees;
• the size and shape of the lower and upper teeth are approximately the same;
• Only the first 2 rows of teeth work.

An interesting fact: within ten years, approximately 24,000 teeth grow, are used and discarded in one individual.

What advantages does a tiger shark have with such uniquely arranged teeth and strong jaw muscles?

• In the literal sense, not only soft tissues are cut, but also the bones of the victims.
• Shells break very easily sea ​​turtles.

Dimensions

After getting acquainted with the tool for capturing prey (uniquely arranged teeth), the question arises: “What is the size of a tiger shark?” As one of the largest shark species in the world's oceans, they are large in size. The largest individual of this species, recorded by the Guinness Book of Records, was a female (pregnant) 550 centimeters long and weighing almost 1.5 tons. She was caught near Australia.

According to unconfirmed reports, the maximum size of a tiger shark is indicated by the numbers 632 cm, 740 and 910 cm.

On average, their length is usually in the range from 325 cm to 425 cm, while their weight is from 350 kg to 635 kg. Sometimes there are larger individuals: males are 450 cm long, and females - 500 cm.

Food and hunting

Watching what a tiger shark looks like, it seems that it is clumsy due to its large physique. But despite this physique, she is an excellent swimmer among the sharks of the Karhariformes order.

When slowly patrolling the territory, it is characterized by low speed, while the fish makes barely noticeable movements. But as soon as the shark smells prey, it changes and becomes very fast. Attacking, she instantly "transitions" to high speed.

How does a tiger shark find its prey, because it hunts even in the dark? Here are the fixtures:

• On its snout there are expanded pores of electroreceptors, thanks to which it captures the most minimal changes in the surrounding electric field.
• The lateral line, located along the sides of the body, captures the minimum vibrations of the surrounding water area.

Tiger sharks hunt at night and alone. They swim far from the shore and rise closer to the surface. Only combed crocodiles can compete for food with them. Killer whales can attack tiger sharks.
This type of shark is very gluttonous and illegible in food. She eats everything.

• crustaceans (lobsters and crabs);
• mollusks (gastropods, bivalves, cephalopods);
• different types of fish, even stingrays and other sharks (grey-blue, the maximum length of which is 250 cm);
• marine mammals (seals, dugongs, sea lions, bottlenose dolphins and some others);
• sea ​​turtles, even such large ones: green, leathery and loggerhead (she eats them out of a strong shell).

Despite the variety of menus, the diet of tiger sharks is based on small animals. When opening the stomachs of large sharks of this species, relatively small fish (20 cm long) were found.

The tiger shark has a very acute sense of smell, which makes it possible for it to catch minimal traces of blood. Perceiving low-frequency sound waves, she confidently finds her prey and in muddy water. Then it begins to circle around the prey and explore it, pushing with its snout. Often the victim is swallowed whole.

A lot of different things were removed from the stomachs of tiger sharks: tin cans, shoes, beer bottles, the remains of dogs and cats, car tires, canisters and many other unexpected items.

This is evidence that sharks are completely illegible in relation to food and can swallow everything.

reproduction

The ability to reproduce occurs in males that have reached a length of 2 - 2.9 meters. Mature females somewhat larger: 2.5-3.5 m in length. Offspring are born every two years on the third. The mating process is traumatic for the female, as the male often inflicts wounds on her, holding her with his teeth.

The tiger shark is an ovoviviparous species. Pregnancy continues more than a year(up to 16 months). The number of babies in the litter is 10-80 individuals, from half a meter to 76 cm in length. After birth, a born shark cub does not receive any care from the mother and is forced to independently ensure its own safety.

The tiger shark, with its sharp teeth, powerful jaws and voracious appetite, has long aroused in us a curiosity mixed with overwhelming fears, but justified.

Tiger sharks are better than many adapted to survive in underwater world. They are found in abundance in warm seas off the coast of the Americas and Africa. Australia and Oceania, and the most "enterprising" predators have been seen more than once in the English Channel and the cold waters of Iceland.

Being excellent swimmers, tiger sharks cover great distances in search of prey, feeling at ease both in shallow water and in estuaries. and at great depths, which makes them especially dangerous for humans.

Some eyewitnesses claim that they saw 9-meter tiger sharks, but, as a rule, their length rarely exceeds 6 m. They got their formidable name not so much for bloodthirstiness, but for striped, like a tiger, marks on the body of young individuals, which, according to gradually disappear with age.

The family of gray sharks, to which tiger sharks belong, unites 48 species, including the blunt and great blue shark. In turn, this family is included in the order of carcharine-shaped sharks that live in many seas and oceans and represent greatest danger for a person.

Like all its relatives, the tiger shark is a vertebrate animal. however, its skeleton does not consist of bone tissue, as in many fish, but of strong cartilage, much lighter and more flexible than bones.

The tiger shark glides smoothly in the water at the very bottom. In a labyrinth of algae-covered stones, it is easy to hide and unexpectedly ambush an unsuspecting victim.

The shark breathes with gills located on the sides of the head.

Streamlining and balance

An encounter with a huge, torpedo-like tiger shark does not bode well. Her slender body effortlessly glides in the water column, driven by the smooth curves of a powerful tail. Pectoral fins located on the belly, high dorsal and powerful caudal fins help maintain balance when moving. Wagging its tail from side to side, it swims forward, changing the speed and direction of movement with the help of its fins. The toothed scales of the tiger shark are smaller and lighter than the scales of other inhabitants. sea ​​depths, which gives her a huge speed advantage.

Undemanding in the choice of menu, the tiger shark always finds something to profit from. If some giant sharks (for example, whale sharks) feed only on plankton (the smallest plants and animals), then the omnivorous tiger shark without hesitation devours everything that turns up - from crabs and lobsters to fish, small sharks, poisonous rays, sea turtles and even marine lions. From her formidable jaws, neither a seagull crouching on the water, nor a crocodile swimming in the mouth of the river will be healthy. Even a fish-ball, capable of destroying any predator, the tiger shark calmly devours without any harm to itself. (The size of the fish-ball is not more than 30 cm, but in case of danger it swells up, becoming twice as large as usual, and many marine predators die of suffocation, choking on this dangerous prey.)

sea ​​scavenger

For the habit of devouring everything indiscriminately, tiger sharks are often called sea scavengers. Entire flocks of tiger sharks are on duty off the coast of many tropical cities, picking up any garbage, including bags and cardboard boxes.

Following the example of other large relatives, the tiger shark hunts alone, relying entirely on its senses.

A female tiger shark has just caught a fish (the tail of the prey is still sticking out of her mouth). Cruising tirelessly in shallow coastal waters, these predators will always find something to profit from.

Keen hearing picks up the convulsive movements of a wounded fish, and pressure receptors in the ears and along the lateral line respond to the vibrations of the water emanating from a potential prey. The shark has an excellent sense of smell, distinguishing the smell of blood from afar, and excellent eyesight. Finally, nature endowed her with the unique ability to perceive the insignificant electrical impulses emitted by the nerves of animals. For these purposes, it serves as a kind of "radar", located at the tip of the snout.

Before rushing to the attack, the shark circles around the future prey for some time. Before the throw, the predator covers its eyes with a thin transparent film, and its gills sharply draw in water in order to push it out at the right moment and create additional acceleration. Having overtaken the victim, the shark snatches off a huge piece with sharp teeth like a saw and swims to the side, waiting for it to weaken. This manner of hunting largely explains why the tiger shark is so dangerous to humans. If a wounded swimmer flounders in the water, bleeding, the shark will instantly appear and will not let him out alive.

A newborn baby tiger shark is more likely to survive than many of its relatives, since it develops in the mother's body. Typically, a female tiger shark produces from 10 to 84 cubs (30-50 on average). After mating, the sperm can be stored in the posterior part of the oviducts of the expectant mother for about a year. Mature eggs leave the ovaries and descend into the oviduct, where they are fertilized. The development of the embryos in the mother's body lasts about ten months. Each embryo is in a separate capsule of a substance similar to transparent plastic, and in the process of growth it feeds on the yolk of its egg.

Sharks ready for birth (about 0.5 m long) break the walls of their capsules, go out through the birth canal and set off in search of food. From that moment on, the mother considers her mission accomplished and in the future does not care about her offspring, so many cubs become victims of other marine life.

Representing a serious danger to humans, tiger sharks, however, are the object of commercial and sport fishing. Leather is made from their skins, and the fat is used as fuel. Considerable damage is done to sharks and people's attempts to protect themselves from their sharp teeth. Many predators die of suffocation, entangled in net barriers, which are often exhibited on the beaches of Australia and South Africa to protect swimmers.

AUSTRALIAN SAND SHARK

The sand tiger shark is found in almost all oceans and everywhere, especially in Australia, enjoys a formidable, if not well-deserved reputation as a ferocious man-eater. The gray skin of the sand shark is all dotted with yellow spots; her belly is white. During pregnancy, several embryos develop in the female's body at different rates, but over time, the largest of them devours its smaller counterparts, and in the end, the mother gives birth to only one cub about 100 cm long. Adult sharks can swallow air, which provides them neutral buoyancy. conservation status

Systematics on Wikispecies

Images at Wikimedia Commons

ITIS NCBI EOL

Tiger sharks are widespread in the tropical and subtropical zone of the World Ocean, where they live both in open waters and near the coast. They are especially common around islands in the central Pacific. Lead night image life. These large predators reach lengths of 5.5 m. They have a highly varied diet that includes crustaceans, fish, marine mammals, birds, cephalopods, sea snakes, and turtles. Inedible objects were found in the stomachs of large individuals. Tiger sharks reproduce by live birth, they are prolific, there are up to 80 newborns in the litter. These sharks are dangerous to humans. They are the target fishery. The fins, hide and liver are valued.

Antique image of a tiger shark called Galeocerdo tigrinus

Taxonomy

The tiger shark was first described by Peron and Lesueur in 1822 as part of the genus Squalus, as a view Squalus cuvier. Later, this species was assigned to the genus described in 1837 by Müller and Henle Galeocerdo. According to modern concepts, it is the only species in the monotypic genus Galeocerdo .

The name of the genus comes from the Greek words. γαλεός - "shark". The species is named after the French naturalist Georges Leopold Cuvier.

area

Tiger sharks are found close to shore, mostly in tropical and subtropical waters around the world. They lead a mostly nomadic lifestyle, stay closer to the equator during the cold months, migrations are associated with warm currents. This species prefers to stay at depth, on the border with reefs, but, pursuing prey, can swim in shallow water. In the Western Pacific, these sharks are found from the coast of Japan to New Zealand. By tagging, it was found that during migrations, tiger sharks are able to overcome up to 3430 km.

This species occurs in large numbers in the Gulf of Mexico, off the coast of North and South America. It is also widely distributed in the Caribbean. In addition, tiger sharks are found off the coast of Africa, China, Hong Kong, India, Australia, and Indonesia.

Tiger sharks have been recorded at a depth of about 900 meters. Some sources state that they can come ashore to depths generally considered too shallow for sharks of their size, and even swim in river estuaries. In Hawaii, tiger sharks are regularly observed at a depth of 6-12 meters and even 3 meters. They often visit shallow reefs, jetties and channels where they can potentially meet humans.

Description

The anterior part of the body is thickened, becoming noticeably narrower towards the belly. large head with big eyes and a short, blunt snout is wedge-shaped and easily turns from side to side. Along upper lip there is a long furrow. The distance from the tip of the snout to the mouth is equal to the distance between the nostrils and much less than the length of the mouth. Behind the eyes are large slit-like spiracles. Nostrils small, distance between them 3 times their width. They are framed in front by a wide triangular fold of leather. The snout of tiger sharks is covered with enlarged pores. These are electroreceptors, allowing them to pick up changes in the electric field. With the help of the lateral line, which stretches along the sides along the entire body, sharks detect the slightest vibrations. aquatic environment. These adaptations allow them to find prey and even hunt in the dark.

The first dorsal fin is high and wide. Its foundation starts behind pectoral fins. It is closer to the pectoral fins than to the ventral ones. The second dorsal fin is small, its height is 2/5 or less of the height of the first dorsal fin. The base is in front of the anal fin. The pectoral fins are wide, sickle-shaped. The length of the pectoral fins from the base to the posterior tips is 3/5 to 2/3 of the length of their anterior margin. Their base is located at the level between the 3rd and 4th gill slits. There is a ridge between the first and second dorsal fins. A low longitudinal keel runs on the caudal peduncle. The anal fin is comparable in size to the second dorsal fin. The upper lobe of the caudal fin is elongated, with a ventral notch below the tip.

The tiger shark has a very large mouth with powerful jaw muscles and characteristic teeth. Each tooth has a beveled top and a serrated blade. The edge of each notch, in turn, is covered with small notches. Upper and lower teeth are similar in shape and size. The teeth are adapted to cut through flesh, bones, and even the shells of sea turtles.

The coloration is gray, the belly is white or light yellow. Until the shark reaches two meters in length, transverse stripes similar to tiger ones are noticeable on its sides - hence the name. These stripes camouflage these fish from their larger relatives. Then the stripes fade, fade. The dorsal surface of adult tiger sharks is dark grey. Especially well the coloring camouflages tiger sharks against a dark background.

Dimensions

This is one of the largest modern sharks. On average, tiger sharks reach a length of 3.25-4.25 m, with a mass of 385-635 kg. Occasionally, males grow up to 4.5 meters, and females up to 5 meters. According to the Guinness Book of Records, one pregnant female caught in Australian waters had a length of 5.5 m and a mass of 1524 kg. There is unconfirmed information that sharks of this species can reach much larger sizes - 6.32 m (Panama Bay, 1922), 7.4 m and even 9.1 m.

Biology

Being very voracious and illegible in food, this shark devours crabs, spiny lobsters, bivalves and gastropods, squids, a wide variety of fish (including rays and other sharks, for example, blue-gray), seabirds, snakes, mammals (including including bottlenose dolphins, white-barreled dolphins, prodolphins, dugongs, less often seals and sea lions) and turtles (including the largest species: loggerhead, green and, possibly, even leathery), which she eats out of the shell. Wide, fairly powerful and strong jaws, combined with large serrated teeth, enable the tiger shark to attack rather large or protected prey, although, in general, small animals form the basis of their diet - the fact that even small ones were found in the stomachs of large sharks fish about 20 cm long. A keen sense of smell gives her the ability to respond to the presence of even faint traces of blood. Capturing low-frequency sound waves, sharks confidently find prey even in muddy water. Sharks circle near the prey and explore it by pushing with their snouts. When attacking, they often swallow their prey whole.

Cannibalism is also characteristic of this species: for example, one large tiger shark ate a smaller representative of its species that got hooked on a tuna line, but was not satisfied and grabbed a neighboring bait, being caught itself. This shark, without excessive disgust, refers to carrion and garbage. The list of edible and inedible items removed from the stomachs is very large and includes the remains of horses, goats, dogs, cats, rats, canisters, car tires, cow hooves, deer antlers, the head and forelimbs of an African crocodile, various rags, boots, bags of coal , tin cans, beer bottles, cigarette boxes, potatoes, leather purse and many other things.

In connection with high risk attacks dolphins often avoid places of concentration of tiger sharks. Tiger sharks may attack injured or sick whales. A group of sharks of this species were documented attacking and eating a sick humpback whale in 2006 off the Hawaiian Islands. Tiger sharks also willingly eat the corpses of whales. In one of these recorded incidents, they, along with a white shark, tore off pieces from the carcass of a whale. Dugongs were found in the stomachs of 15 of 85 tiger sharks caught off the coast of Australia. In the course of research, teeth marks from a shark or killer whale were also found on the body of one of the dugongs. In addition, the change in dugong local habitats was of a nature that is characteristic of animals that tiger sharks commonly prey on.

Every year in July, tiger sharks gather off the coast of the western islands of Hawaii, when dark-backed albatross chicks begin to fly, still unable to stay in the air for a long time and forced to sink into the water.

Males reach sexual maturity at a length of 2-2.9 m, and females - 2.5-3.5 m. Females bring offspring once every 3 years. During mating, the male holds the female with his teeth, often inflicting wounds on her. In the Northern Hemisphere, mating usually occurs between March and May, with sharks born from April to June the following year. In the Southern Hemisphere, mating occurs in November, December or early January. The female, ready to produce offspring, loses her appetite to avoid cannibalism. The tiger shark is the only ovoviviparous species in its family Carcharhinidae. The cubs hatch from the embryo sac inside the mother and are born when they are fully developed. During the breeding season, female sharks gather in flocks to protect offspring from males. Pregnancy lasts 13-16 months. There are from 10 to 80 sharks in a litter. Newborns, as a rule, have a length of 51 to 76 centimeters. The maximum life expectancy is unknown, but it is estimated that it can reach 45-50 years. The age of the tiger shark, whose precaudal length was 2 m, was estimated at 5 years, and 3 m - 15 years.

Human interaction

In tropical waters, the tiger shark is perhaps the most dangerous species for humans. There are many cases when human body parts were found in the stomachs of captured sharks. Some of the finds can probably be explained by the devouring of corpses, but many of the victims undoubtedly met the shark while still alive and well. Attacks have been recorded in many areas - off the coast of Florida, the Caribbean islands, Senegal, Australia, New Guinea, the Samoa Islands and in the Torres Strait. These attacks took place both offshore and on the high seas. In 1937, a tiger shark killed two young men swimming off the coast of New South Wales (Australia). She was subsequently caught with the remains of her victims in her stomach. In 1952, near a small island in the Puerto Rico region, a shark attacked an underwater hunter who harpooned a fish. In 1948, a boat heading for the coast of Florida was attacked.

On average, 3-4 attacks per year occur in Hawaii, most of the attacks do not lead to the death of the victim. This is a surprisingly low number of attacks, given the fact that thousands of people swim, surf and dive in Hawaiian waters every day. In October 2003, newspapers were full of reports of a tiger shark attack. Then the American surfer Bethany Hamilton, who at that time was 13 years old, was bitten off by a shark arm to the shoulder. Despite the attack, after a while she returned to surfing. Hamilton is currently a professional surfer. After this incident, a large tiger shark was caught. Based on its size and the shape of its jaws, it has been suggested that this is the same shark that attacked Hamilton. By 2011, there were 169 tiger shark attacks on the International Shark Attack File, of which 29 were fatal. Between 1959 and 1976, 4,668 tiger sharks were shot to protect the tourism industry. Despite these efforts, the number of attacks is not decreasing. It is illegal to feed sharks in Hawaii. South African shark behaviorist and shark diver Mark Addison demonstrated in 2007 on the Discovery Channel how divers can swim with tiger sharks without a protective cage.

Tiger sharks are caught for their fins, meat and liver. They are the object of the target fishery, caught as by-catch. The number of tiger sharks has somewhat decreased in areas of intensive fishing due to a decrease in the food supply, but in general their situation is quite stable. Increasing demand, especially for shark fins, may lead to further stock declines in the future. The International Union for Conservation of Nature has given the tiger shark Near Threatened conservation status. In 2010, Greenpeace added the tiger shark to the seafood red list, which includes the most widely traded fish worldwide.

see also

Notes

1. Gubanov E.P., Kondyurin V.V., Myagkov N.A. Sharks of the World Ocean: A guide. - M.: Agropromizdat, 1986. - S. 132. - 272 p.
2. Lindbergh, G. W., Gerd, A. S., Russ, T. S. Dictionary of marine names commercial fish world fauna. - Leningrad: Nauka, 1980. - S. 40. - 562 p.
3. Reshetnikov Yu. S., Kotlyar A. N., Russ T. S., Shatunovsky M. I. Five-language dictionary of animal names. Fish. Latin, Russian, English, German, French. / under the general editorship of acad. V. E. Sokolova. - M.: Rus. yaz., 1989. - S. 32. - 12,500 copies. - ISBN 5-200-00237-0.
4. Tiger Shark (English) at the FishBase Database.
5. Galeocerdo cuvier (English) . The IUCN Red List of Threatened Species.
6. Lesueur, C.A. Description of a Squalus, of a very large size, which was taken on the coast of New Jersey // Journal of the Academy of Natural Sciences of Philadelphia. - 1822. - Vol. 2 (ser. 1). - P. 343-352.
7. Craig Knickle. tiger shark. Biological profile (indefinite) . Florida Museum of Natural History.
8. Compagno, Leonard J.V. Sharks of the World: An Annotated and Illustrated Catalog of Shark Species Known to Date. Part 2. Carcharhiniformes. Rome: Food and Agricultural Organization of the united Nations, 1984. - P. 503–506. - ISBN 92-5-101384-5.
9. Dr. Erich K. Ritter. Fact Sheet: Tiger Sharks (indefinite) . shark info.
10. (indefinite) . MarineBio.org. Retrieved 31 December 2015.
11. Kashmira Lad. Habitat of a Tiger Shark (indefinite) . Buzzle.
12. Life of animals. Volume 4. Lancelets. Cyclostomes. cartilaginous fish. bony fish/ ed. T. S. Rassa, ch. ed. V. E. Sokolov. - 2nd ed. - M.: Education, 1983. - S. 37-38. - 300,000 copies.
13. Tiger Sharks, Galeocerdo cuvier (indefinite) . http://marinebio.org/.
14. Tiger Shark (indefinite) . Newbrunswick.net.
15. Akimushkin I. I. Birds. Fish, amphibians and reptiles. - 3rd ed. - M.: "Thought", 1995. - S. 271-282. - 462 p. - (Animal world). - ISBN 5-244-00803-X.
16. Heithaus, Michael R. Predator–prey and competitive interactions between sharks (order Selachii) and dolphins (suborder Odontoceti): a review // Journal of Zoology. - 2001. - Vol. 253, No. 1. - P. 53–68. - DOI:10.1017/S0952836901000061 .
17. Wood, Gerald L. The Guinness book of animal facts and feats. - Guinness Superlatives, 1976. - P. 146. - ISBN 9780900424601.
18. Summary of Large Tiger Sharks Galeocerdo cuvier (Peron & LeSueur, 1822) (indefinite) . Home Page of Henry F. Mollet.
19. Heithaus, Michael R. The biology of tiger sharks, Galeocerdo cuvier, in Shark Bay, Western Australia: sex ratio, size distribution, diet, and seasonal changes in catch rates // Environmental Biology of Fishes. - 2001. - Vol. 61, No. 1. - P. 25-36. - DOI:10.1023/A:1011021210685 .
20. Crocodiles vs sharks (indefinite) . sandcroc2014. Retrieved 28 December 2015.
21. Croc Spotted Devouring a Tiger Shark (indefinite) . www.explore-townsville.com. Retrieved 28 December 2015.
22. Incredible moment killer whales hunt and kill a tiger shark | Daily Mail Online (indefinite) . mail online. Retrieved 23 December 2015.
23. Christopher G. Lowe, Bradley M. Wetherbee, Gerald L. Crow, Albert L. Tester. Ontogenetic dietary shifts and feeding behavior of the tiger shark, Galeocerdo cuvier, in Hawaiian waters // Environmental Biology of Fishes. - 1996. - Vol. 2, no. (47) . - P. 203-211. - ISSN 0378-1909. - DOI:10.1007/BF00005044.
24. M. Heithaus, L. Dill, G. Marshall, B. Buhleier. Habitat use and foraging behavior of tiger sharks ( Galeocerdo cuvier) in a seagrass ecosystem (English) // Marine Biology. - 2002. - Vol. 140.-Iss. 2. - P. 237-248. -