Whale shark. Whale shark lifestyle and habitat

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There have been many legends and rumors about this giant fish that lives in the southern seas for a long time. People, frightened by its appearance and size, described the whale shark as a terrible lone monster from the ocean abysses. Only after a long time it became clear that this predator, despite its terrifying appearance, was not at all dangerous. However, the whale shark remains one of the most mysterious fish on the planet to this day.

Scientific classification

• Kingdom: Animalia (animals)
• Phylum: Chordata
• Class: Chondrichthyes (cartilaginous fishes)
• Order: Orectolobiformes (wobbegongs)
• Family: Rhincodontidae (rhincodonts)
• Genus: Rhincodon (whale sharks)
• Species: Rhincodon typus (whale shark)

The whale shark was first described by Andrew Smith in 1828 from a specimen harpooned in Table Bay, South Africa. Historically, family, genus, and species names have had many synonyms (alternate scientific names). The first scientific edition of the genus name appeared as Rincodon, despite Smith's desired name Rhineodon. However, in 1984, the International Commission on Zoological Nomenclature banned the previous generic variations in favor of the genus name Rhincodon and the family Rhincodontidae.

Significance in culture and tourism

Even in those regions where the shark is most common, it does not have a special role in the culture of a particular nationality. And only Japanese and Vietnamese fishermen treat this giant with special trepidation. So, in Japan it is believed that meeting a giant fish is a good omen. Also in this country, where seafood forms the basis of the daily diet, whale shark meat is practically not consumed.

Vietnamese sailors also treat it with great respect, believing that fish not only brings good luck, but is also a kind of sea deity. The Vietnamese even recorded their attitude in the peculiar folk name of this giant, which is literally translated from their language as “Mr. Fish.”

https://youtube.com/watch?v=e2qmWfvlllk

The shark has acquired great importance in the tourism business. In some countries, where the species is still relatively common, entire tours are organized in which everyone can not only watch the giant from aboard a sea vessel, but even get close to it by scuba diving.

Diving tours are especially popular in Mexico, the USA, the Maldives and Seychelles, Australia, and the Caribbean. Unfortunately, such human entertainment does not contribute in any way to increasing the population, but, on the contrary, negatively affects the peace and lifestyle of these largest fish, of which there are already only a few left.

Varieties

Photo: BlueSun2 Boat Charters

Recent studies using mitochondrial DNA and microsatellite analysis have shown that there are two main subpopulations of whale sharks that differ slightly in size and behavior:

• Indo-Pacific population;
• Atlantic population.

The Indo-Pacific population ranges from the western Indian Ocean to the Philippines, Taiwan, Thailand, and the western and central Pacific Ocean. The size of this population is rapidly declining due to overfishing in the area. It is known that the Atlantic population is characterized by greater aggregation in feeding areas.

Pelagic largemouth shark

Appearances can be deceiving. The pelagic largemouth shark looks very predatory, but it is not dangerous to people. Due to the small size of its teeth, its diet consists exclusively of plankton and small fish. Therefore, she always swims with her mouth wide open, thus swallowing water and food. The population of this shark species numbers about 100 individuals, which extremely rarely approach the coastline, so a human encounter with this predator is unlikely.

Geographical range

The whale shark has a very wide distribution, living in all tropical and warm-temperate seas, except the Mediterranean Sea. The fish is found throughout the Atlantic Ocean, from New York through the Caribbean to central Brazil and from Senegal to the Gulf of Guinea. The whale shark is also found in the Indian Ocean throughout the region, including the Red Sea and the Persian Gulf. In the Pacific Ocean it is found from Japan to Australia, from Hawaii and California to Chile.

The whale shark has a circumterrestrial distribution , living in seas between 30 degrees north latitude and 35 degrees south latitude. Almost all coastal countries at these latitudes have recorded whale sharks in their waters. This species can be regularly found in the coastal waters of Australia, Belize, Ecuador, Mexico, the Philippines and South Africa.

• Biogeographic regions: Indian Ocean, Pacific Ocean, Atlantic Ocean, Arabian Sea, Red Sea

A little about reproduction

This huge fish has been observed for more than a century, but scientists still have very little information about its reproduction. First of all, it is known that she is ovoviviparous , i.e., embryos develop in the womb in characteristic egg capsules, after which they hatch there and are then born into the world.

Newborn sharks are about 0.5 meters long and can go without food for quite a long time, since they accumulate a sufficient amount of internal nutritional reserves while still in the womb of the mother. Proof of this is the case when a living and fully developed baby shark was removed from the belly of a caught shark. The baby was placed in an aquarium, where for the first two weeks he ate absolutely nothing, but was alert and active.

Research at the end of the twentieth century also found that this representative of the sharks goes through an extremely long process of puberty, lasting up to 30-50 years. The full lifespan of the species ranges from 70 to 100 years. There is unverified information even about 150-year-old individuals, but this has not been proven by science.

Habitat

Photo: Time Out Doha

Unlike most sharks of the same order, which are benthic (living on or near the bottom) species, the whale shark is a pelagic (open sea) species. Research shows that this shark prefers warm waters with temperatures around 21-30 °C . They feel comfortable in deep and shallow coastal areas, as well as in subtropical zones, reef lagoons and coral atolls.

These giant zooplancivores are usually found in coastal areas with high food productivity. Data collected from archival tags showed that the species can dive to depths exceeding 1,900 meters and can also tolerate temperatures as low as 7.8°C.

• Habitat: tropical, temperate
• Aquatic biomes: pelagic reef, coastal, atolls, open sea

Home range

This is a migratory species of shark, constantly returning to the same feeding area. Because whale sharks migrate across oceans, they do not maintain a home range or defend a personal territory. At different times of the year, different geographical locations are preferred. Whale sharks can undertake either extremely localized or large-scale transoceanic migrations.

Whale sharks travel a distance of about 24-28 km daily. Recent studies have shown that individuals also undertake long-term migrations (up to 37 months) over very long distances of up to 13,000 km , most often from Mexico to the Kingdom of Tonga and from East Africa to Thailand. It is believed that the movements of whale sharks are closely related to plankton blooms and spawning.

Whale sharks have been found to congregate on the continental shelf of Australia's central west coast every March and April, particularly in the Ningaloo Reef area. This phenomenon is explained by the high concentration of local zooplankton.

Giant shark

Despite their impressive size and dangerous appearance, giant sharks are not interested in humans as food. Therefore, a giant shark swimming nearby does not pose any threat to you. This species feeds exclusively on plankton and fish, showing neither interest nor aggression towards people. Even despite their powerful jaws rich in teeth, giant sharks are considered peaceful and not dangerous. And they can be found everywhere in both northern and temperate waters of the world’s oceans.

Distinctive characteristics

Whale sharks are easily distinguished from other shark species by their enormous size, unique checkerboard pattern of spots and stripes on their backs, three prominent longitudinal ridges (keels) along their upper sides, and their distinctive head and mouth.

Appearance

A streamlined, spindle-shaped body and a depressed, wide and flattened head characterize the whale shark. The fish's body is widest in the middle and tapers towards the head and tail.

The fish's mouth is transverse, very large (reaches 1.5 meters in diameter), located almost at the tip of the muzzle. The mouth contains more than 300 rows of tiny, hooked, replaceable teeth and 20 filter pads.

The gill slits are very large and internally modified into filter sieves , which are used to retain small prey. On the front of the snout, whale sharks have a pair of small nostrils with vestigial barbels; these nostrils lack the folds and grooves characteristic of other shark species.

The first dorsal fin is much larger than the second dorsal fin and is located at the back of the body. crescent-shaped in adults ; in small juveniles the upper lobe is significantly longer than the lower one. In addition, males have clasps, which are modified anal fins.

Coloring

Whale sharks are greyish, bluish or brownish above, with a "checkerboard" pattern of creamy white spots on the surface between pale, vertical and horizontal stripes. The ventral part of the body is white. The coloration remains unchanged throughout the whale shark's life, making it ideal for identification.

Photo: DIVE Magazine

The purpose of the distinctive pattern on the whale shark's body is unknown. Many bottom-dwelling fish have markings on their bodies that act as camouflage. The whale shark's markings may be the result of its evolutionary relationship with bottom-dwelling carpet sharks. Distinctive markings in pelagic species may be associated with social activities such as postural displays and recognition processes.

Anatomical features

The skin is studded with dermal denticles , which are scaly, tooth-like structures that are considered hydrodynamically important. They reduce resistance and function as a form of parasite repellent.

The whale shark's skeleton is composed of thick, flexible cartilage and lacks a rib cage, significantly reducing body weight. The body's rigidity is provided by a subcutaneous complex of collagen fibers that act as a type of flexible "corset" to which the motor muscles are attached from the spine, forming a lightweight and mechanically efficient system.

Dimensions

The whale shark is the largest living shark and fish in the world. Adults reach 13 meters in length. The largest recorded individual was 20 meters long. Both males and females reach maturity when they reach 9 meters in size.

• Body weight: maximum 30,844 kg
• Body length: maximum 20 meters

Nutrition

The feeding method of the whale shark is similar to that of baleen whales, which also feed on plankton. However, if baleen whales filter water with food through the baleen plates growing from the palate of the upper jaw, then the whale shark’s filtering apparatus consists of 20 cartilaginous plates connecting individual gill arches to each other like a lattice (the side of its cells is only 1-3 mm) , and on which the skin teeth are located. When feeding, a whale shark is capable of passing up to 6 thousand cubic meters of water per hour through its mouth. Having filled its mouth with water and plankton, the shark closes it, after which the water is filtered through the gill openings. Then the filtered food organisms enter the stomach through a narrow (no more than 10 cm in diameter) esophagus. It is in connection with this method of feeding that the teeth of the whale shark are very small and numerous; they serve not for biting, but for “locking” prey in the mouth.

The whale shark everywhere feeds on almost everything that falls into its mouth and that it can swallow. These are primarily various planktonic organisms several millimeters in size - crustaceans, small squids, jellyfish, etc. Small schooling fish are also eaten - anchovies, sardines, small mackerel and even small tuna. The presence of whale sharks often serves as a sign for fishermen of the presence of game fish, such as tuna - as a rule, whale sharks stay where there is a large amount of plankton and, therefore, other fish that feed on it.

When feeding, the shark moves very slowly - about 1 m/s, and often almost stops, hovering in the water, and, sucking in plankton, sways up and down, moving its head to the sides. Often the fish stays almost vertical to the surface. Then, if the excitement is strong enough, in the depressions between the waves you can see the head of a shark emerging from the water. A case is described in which a whale shark sucked up plankton (apparently larvae of coral polyps) from the surface of corals; at the same time, the fish was kept at an angle of 45° to the reef surface. At the Ningaloo reefs, the massive accumulation of whale sharks is explained precisely by the high density of polyp larvae, as well as small planktonic animals that feed on them and also serve as food for the whale shark. Often the shark sucks in food that is located directly below the surface of the water (near-surface plankton consists mainly of small crustaceans such as copepods and sergestids, bristlejaws, as well as fish larvae). Then the upper part of its mouth - about 15% in height - appears above the water. A shark can graze near the surface for a very long time, spending on average about 7.5 hours a day.

A feeding shark makes 7-20 swallowing movements per minute, with movements of the jaws occurring simultaneously with movements of the gill slits. When there is an abundance of food, the fish eats so much that its belly protrudes greatly. It was estimated that a shark 4.33 m long swallowed about 1.5 kg of food during an hour of feeding in water with a normal plankton density (4.5 grams per cubic meter), and another individual, 6.22 m long, swallowed 2.76 kg. This roughly coincided with the food consumption of whale sharks observed in aquariums.

Lifestyle and behavior

They are usually solitary animals, although aggregations of several individuals have been reported in various locations; the largest known cluster is off Contoy Island in the Caribbean Sea. Aerial photography here recorded up to 420 individuals over an area of ​​18 square kilometers, of which an average of 74% were males.

Whale sharks exhibit the ability to learn . Individuals in captivity exhibit changes in behavior; When keepers arrive with food, whale sharks begin to swim in tight circles near the feeding area. They are also known to sometimes probe the nets of local boats for small fish.

Photo: Wildestanimal

It is a strong but usually slow swimmer. Juvenile and adult whale sharks cruise at speeds of up to one meter per second and continue at this speed for many hours without rest. They change their dive mode depending on environmental or bathymetric conditions. Their diving patterns are thought to be regulated by circadian rhythms, which can be influenced by diurnal light and dark cycles. Whale sharks spend most of the day near the surface and dive deeper at night.

How many years do sharks live?

Here it is immediately worth clarifying that for many species of sharks the exact lifespan is not known: not every scientist can immediately give at least approximate figures for how many years sharks live.

This is due to various factors such as:

• the danger of working with predators;
• the impossibility of constant observation of some species in nature or keeping them in captivity;
• inaccuracy of methods for determining their age, or their complexity;
• poor knowledge of the biology of some species in general.

Since sharks grow throughout their lives, it is impossible to determine the exact age only by external signs; You can only determine the moment of puberty.

The most common two methods of determining age are: by rings on a section of a vertebra using an electron microscope and by radiocarbon dating of some cells, for example, the retina of Greenland sharks (but more on them a little later).

The first way to find out how many years sharks live is the most common, as it is relatively cheap and simple.

This principle of determining life expectancy is similar to determining the age of trees. But there is an important nuance! The fact is that the vertebrae of a shark consist of layers that grow downwards during the life of the animal.

The alternating white and black pattern may be too thin and too close together to accurately identify the age of a cartilaginous fish. In addition, the formation of belts does not necessarily correspond to the annual cycle.

That is why the question “How many years do sharks live?” - one of the most intriguing not only among biologists and researchers, but also among ordinary lovers of these underwater predators.

Below are approximate life expectancy values ​​for various shark species based on currently available research.

Communication and perception of the surrounding world

Whale sharks have small, round eyes located on the side of their heads. They provide a wide field of view. The broad, blunt shape of the head and the position of the eyes suggest that the fish may have binocular vision . Whale sharks' eyes can track swimmers from 3 to 5 meters away, suggesting they are capable of detecting objects at close range.

Photo: Brent Durand

Most sharks have ampullae of Lorenzini, which are pit-like sensory organs clustered around the head that detect weak electrical fields. The whale shark's inner ear is the largest in the animal kingdom, and the diameter of the semicircular canals is close to the theoretical maximum dimensions for such structures. With such large auditory structures, it is likely that whale sharks are most sensitive to long-wavelength and low-frequency sounds, suggesting that some sort of auditory communication may exist between conspecifics.

The olfactory capsules of whale sharks are spherical and quite large, so it is likely that they would have the same chemo-sensory detection abilities as other wobbegong-like species such as nurse sharks.

Photo: DIVE Magazine

Whale sharks have a mechanosensory system in the lateral line, but its capabilities are unknown. The lateral line allows fish to respond to water currents (rheotaxis). Whale sharks can determine the direction of their movement by following the Earth's magnetic field , which is thought to aid them in navigation. The lateral line also aids in prey detection, feeding, and prey capture.

Brownie shark

“Scary on the outside, but kind on the inside,” the goblin shark is considered safe for people. Moreover, not a single case of this shark attacking a person has been recorded in the world. Although its appearance can scare even the most fearless diver, it is not something to be afraid of. The razor-sharp teeth of this predator are designed to hunt other fish and sharks, squid and crustaceans, but not people. In addition, representatives of this species prefer deep-sea parts of the ocean, so their encounter with humans is unlikely.

Eating habits and hunting tactics

Whale sharks are known to prey on a range of planktonic and small nektonic organisms that are spatiotemporally heterogeneous. These include:

• krill;
• crab larvae;
• small crustaceans;
• jellyfish;
• sardines;
• anchovies;
• mackerel;
• tuna;
• squid.

Phytoplankton (microscopic plants) and macroalgae (larger plants) may also form part of their diet. Individuals feed during the day, at dusk and after dark.

When filter feeding, the whale shark swims forward at a constant speed with its mouth partially or fully open, displacing prey particles from the water by moving forward. This is also called "passive feeding" since the gills are practically not pumped. This type of feeding usually occurs when prey densities are low.

Suction feeding is achieved by the force of opening the mouth and swallowing prey. When the mouth is closed, water is released through the gills, filtering out the caught prey. Whale sharks often do this in a stationary, vertical or horizontal position. This type of feeding is associated with medium-density prey.

Whale sharks also have several rows of small teeth, but these do not appear to play any role in feeding. With all feeding methods, the filter pads become clogged with particles at some point, and the whale shark clears them by backwashing, appearing to cough underwater in a stream of waste.

Photo: Carmelo Lopez Abad

What does a whale shark eat?

Photo: Great whale shark

Like other types of sharks, this fish belongs to the category of predators. However, one cannot blame her for bloodthirstiness. Despite its menacing appearance and equally terrifying Latin name, the “teeth-gnashing” whale shark feeds on zooplankton and small schooling fish (small tuna, mackerel, sardines, anchovies). This fish uses its teeth not to chew its prey, but to prevent it from escaping from its giant mouth. In other words, these are not millstones for grinding food, but peculiar “locks” for locking it.

Like baleen whales, the shark “grazes” for a long time. Taking water into her mouth, she strains out the plankton. The fish closes its mouth, and the water comes out through the filter gills. Thus, only those inhabitants of the ocean remain in the fish’s mouth that are able to penetrate the fish’s narrow esophagus (its diameter reaches only 100 mm). To get enough, a whale shark must spend about 8-9 hours feeding every day. In an hour, it passes about 6 thousand cubic meters of ocean water through its gills. Sometimes small animals clog the filters. To clear them, the fish “clears its throat.” At the same time, the stuck food literally flies out of the animal’s mouth.

The stomach capacity of whale sharks is about 0.3 m3. Fish spend part of their prey on maintaining energy balance. A certain amount of food is stored in a special compartment of the stomach as a reserve. Some of the nutrients are deposited in the animal’s liver - a kind of energy storehouse. This can be called a rainy day reserve. The liver of a whale shark is relatively small in size, and is in no way suitable as a “float” for holding a large, heavy body in the water column. These fish do not have a swim bladder. For better buoyancy, the animal swallows air, releasing it when diving into the ocean depths.

According to recent studies conducted by Japanese zoologists, the diet of whale sharks turned out to be somewhat more diverse than originally thought. In addition to animal food, which undoubtedly forms the basis of the menu, they also feed on algae, and, if necessary, they can also starve. Fish “fast” mainly during migration from one food source to another. With a shortage of basic food, the whale shark is content with a vegetarian “diet” for some time.

Reproduction and development of young

There has been great scientific debate about the development of whale sharks for decades. This continued until 1995. At this time, an 11-meter female whale shark was harpooned off the east coast of Taiwan, and 300 fetuses ranging from 42 to 63 cm in length were removed from two uteruses. This discovery proved that the whale shark is ovoviviparous (the eggs hatch in the mother's uterus when the female gives birth live young).

This whale shark's egg capsules were amber in color, smooth in texture, and had breathing holes on each side. The sex ratio was approximately 1:1. Female whale sharks appear to give birth while feeding in the rich waters of the Kuroshio Current. It is also clear that the southeastern coastal waters of Taiwan, the Philippines and India are an important nursery for whale sharks during the summer months.

Photo: DIVE Magazine

There is currently limited data to accurately determine the age at sexual maturity of whale sharks, but it is estimated that this could take up to 30 years. Information on the frequency with which they may occur and when and where this may occur is currently not available. It is only obvious that females do not show parental care towards the cubs after their birth. This is typical for almost all sharks.

• Mating system: polygamy
• Method of reproduction: ovoviviparity
• Number of offspring: several hundred cubs

How long do white sharks live?

Alas, the exact lifespan of white sharks is still not known, despite the fact that the question “How long do white sharks live?” one of the most popular regarding the most dangerous species among underwater predators.

Estimating age in white sharks is particularly challenging. The vertebrae are made up of layers of cartilage tissue arranged sequentially throughout the shark's life.

These layers alternate in patterns of light/dark stripes that may be narrower and less distinct than in other shark species, but the stripes do not necessarily indicate annual growth.

Large species of white sharks can be stunted in growth due to various types of phenomena in the environment, due to which the growth of the layers slows down, but the shark still lives. And one such stripe can grow not for 1 year, but for example 1.5, if not two.

That is why it is currently not possible to determine the exact figure for how long white sharks live.

Also, determining the lifespan of white sharks is greatly affected by the fact that white sharks reach sexual maturity at approximately 24-26 years, which is quite late. After this point, predators grow relatively slowly and it is believed that age greatly depends on the conditions in which they live.

Today, thanks to a combination of both methods of identifying the age of sharks, in the latest studies, scientists have finally announced how long white sharks live: according to rough estimates, the age of the largest male was more than 73 years, and the female - 60 years.

But the study of this issue continues. In addition, sharks have an interesting feature: the closer scientists get to solving one question, in this case, how many years do sharks live, the more other questions they have about these ancient predators.

Watch video - one of the largest white sharks: a female about 56 years old

Some scientists admit that touching the secrets of sharks is the same as opening Pandora's box.

And now, in addition to the question “How long do white sharks live?” Scientists want to find out in particular whether female sharks can live longer than males, and how the life ages of sharks correlate with the stages of evolution that have occurred with them over 400 million years.

Natural enemies

Whale sharks have very few natural predators due to their large size as adults. Human activity and poaching have significantly reduced their numbers. Small specimens are vulnerable because they are not yet fully developed and their small size makes them easy prey for blue marlin and blue sharks. Killer whales have been known to attack and eat whale sharks up to 8 meters in size. In 2002, a whale shark was discovered with a missing fin and large bite marks, most likely caused by a great white shark.

The whale shark's best protective adaptation is its skin, which is covered with dermal denticles, which make the covering very tough, as well as a thick layer of cartilage.

European angelfish

The European (or common) angelfish shark is also known as the European squat. Due to its unusual body shape for sharks, it can be mistaken for a stingray, hence the name squatina (from the Latin squatina). This predator uses the advantages of its body to hunt in the bottom part of the sea and feeds on fish, crustaceans and mollusks, so encountering it while swimming is unlikely. Unless, of course, you are planning to dive to the bottom of the sea. Otherwise, be careful, as angel sharks lead a bottom-dwelling lifestyle and often hide in the sand or between rocks. Try not to step on them. Typically, despite having strong jaws and sharp teeth, angel sharks are not the first to attack humans. The exception is those rare cases when people themselves provoked aggression, forcing them to defend themselves. However, an attack by this predator on a person, as a rule, does not have serious consequences for the life and health of the victim, since their bites are weak and insignificant.

Meaning to people

Photo: DIVE Magazine

Whale sharks are part of national and international trade, a cornerstone of marine tourism and are often targeted by fisheries. The only fishery that existed in the Atlantic was organized in Cuba, where about 9 sharks were caught annually, but in 1991 it was banned.

Whale shark meat is a delicacy in Taiwanese restaurants . Although the cartilage fibers in the fins are not suitable for making soup, they are sold as display or trophy fins in Asian restaurants. In Pakistan, the meat is traditionally consumed fresh or salted, and whale shark liver oil is used to treat boat hulls and polish shoes.

Eco-tours for scuba diving and whale shark watching have now been established in several locations, including Mexico, Australia, Southeast Africa, Belize, Honduras, the Philippines, Seychelles and the Maldives. In some areas, tourism has developed and become a significant source of income due to laws prohibiting the fishing of whale sharks.

Threats

The main threat to the whale shark population is considered to be commercial fishing. Despite conservation measures taken, whale shark hunting in tropical countries (mainly Southeast Asia and India) continues due to population growth and, accordingly, a growing need for protein food. This is one of the main reasons for the decline in whale shark populations in the Pacific and Indian Oceans. The exceptionally long maturation and slow rate of reproduction prevent the rapid recovery of the population. The natural decline in the whale shark population is 5-6% per year.

Overall, research into the global population of whale sharks shows that their numbers are in constant decline. A study of the number of sightings of large whale sharks, particularly off Taiwan, has caused serious concern among scientists. Until the late 1990s, the average size of whale sharks observed off the northeastern coast of the island was quite large (the range of lengths of observed sharks was 10-20 m). However, observations from 2000 to 2004 showed that the average size of the shark decreased to 4.6 m. According to the researchers, this may be the result of overfishing, which led to the catch of large females. Research into the whale shark fishery off Bohol (Philippines) showed that 624 whale sharks were caught there between 1990 and 1996, and the fishery was constantly expanding. But the average catch per boat was constantly falling - from 1993 to 1997 it decreased by 2.5-3 times. According to the FAO, catches in Taiwan, which reached 100 animals per year, dropped to less than 10 animals by the 1990s. A serious negative role can also be played by the tendency of sharks to return after migrations to their former habitats, which leads to their rapid catch and impoverishment of local stocks.

Danger to people

Photo: Stephen Frink

Whale sharks are generally considered harmless animals. There are many videos on the Internet of divers swimming near a whale shark, freely touching the fish’s body. However, there have been several cases of whale sharks ramming sport fishing boats, possibly after being provoked. Typically, these fish are more at risk of accidental collisions with vessels while basking or feeding on the surface.

How long does the Greenland shark live?

But this question will be the most interesting - how many years does the Greenland polar shark live?

Today, the Greenland shark (Somniosus microcephalus) is recognized as the longest-living vertebrate in the world. Before her, the palm of leadership was held by sperm whales, living up to 211 years.

The oldest representative of cartilaginous fish, 5 meters long, was 392 years old!!!

And scientists said that this is not the limit. According to their estimates, the animal could live for about another 120 years, since no signs of aging were observed in the body. That is, if compared with the age of a person, the Greenland shark under study was 40 years old (by human standards) at the time of its study.

That is, theoretically, the Greenland shark will live 500 years or more. Unless, of course, it catches the eye of these curious scientists who, using a scalpel, are looking for the answer to the question “how long do sharks live?”

Watch the video - how old is the oldest shark on the planet (of those studied):

Such a great age was determined by radiocarbon dating of the cell nuclei in the retina of these predators. The older the individual, the more layers of lens fibers the lens nucleus has.

By peeling off these layers like cabbage leaves, scientists can get to the embryonic nucleus of the lens, which is formed in a shark before birth, and determine the age of the fish based on the carbon-14 isotope content in it.

The exact reason for such phenomenal longevity is unknown, and scientists are inclined to believe that this is due to slow growth due to slow metabolism and harsh living conditions in the habitat of this shark (the predator lives in the waters of the North Atlantic, where the water temperature is close to 0 degrees).

This is also due to living at a depth of up to 2200 meters, and a pressure of over 200 atmospheres (200 kg or more for each square cm of body).

The annual increase in body length in this species of shark is only 0.5-1 cm. These sharks are one of the least studied, and they still have a lot to surprise scientists with.

Therefore, the question “How long does the Greenland shark live?” will appear more than once in the headlines of popular scientific journals.

More detailed information about how many years Greenland sharks live can be read in the article: 400-year-old Greenland shark is the longest living animal on the planet

Determining the age of the Greenland shark

To determine the lifespan of Greenland sharks, researchers radiocarbon dated the nucleus of the eye lens of 28 female sharks.

Scientists' analysis has shown that the average lifespan of Greenland sharks reaches at least 272 years, making them the longest-living record among vertebrates.

The researchers estimated the age of the largest shark studied (502 centimeters long) at 392 ± 120 years, and individuals whose size was less than 300 centimeters turned out to be younger than a hundred years. The study authors also claim that Greenland sharks reach sexual maturity at approximately 150 years of age!

Would you like to live as long as Greenland sharks live?

Save Status

"endangered" and their populations are declining, according to the International Union for Conservation of Nature (IUCN) They face a high risk of extinction due to factors such as geographic range decline and unregulated fishing. Threats are created by human recreation and various industries, including oil and gas drilling, and marine resource extraction.

Moreover, whale sharks are threatened by shipping lanes. About one in five whale sharks have been injured at least once by commercial vessels, boats and propellers.

Leopard shark (Triakis semifasciata)

The leopard shark is a species of shark found primarily along the Pacific coast of North America, from Oregon to Mexico. They can be easily identified by their black leopard spots and markings on their backs.

Leopard sharks usually live in large schools in the shallow, murky waters of bays and estuaries. Although they are active predators, they feed primarily on shrimp, caviar, clams, spoonworms and other small animals found in the mud. Leopard sharks are known for swimming away when people approach them.

Leopard shark

Did you know?

1. Whale sharks can control their buoyancy by gulping a little air, just like sand tiger sharks.
2. Their lifespan can exceed 100 years.
3. The ancestors of whale sharks appeared during the Eocene period, 35-58 million years ago.
4. This fish has a thick 10-centimeter skin.
5. It is believed that only one in ten cubs survive.
6. In Taiwan, up to hundreds of whale sharks are caught every year.
7. They are capable of filtering up to 6,000 liters of water every hour.
8. Unlike true whales, which must come to the surface to breathe, whale sharks breathe through gills, like other fish.

Common sand shark

The temperate and subtropical waters of the World Ocean are inhabited by the common sand shark, which seems threatening only in appearance. In relation to humans, this predator is quite peaceful and calm, unless it is deliberately provoked, of course. Its open mouth while swimming can be scary, but this is just a way of hunting fish, and not an attempt to swallow you. Since most of the time the sand shark is located in the bottom part of the sea, encountering it is unlikely.