Elephant seals: species, description, reproduction, nutrition, behavior and conservation status. Sea elephant - a giant of the northern and southern seas. A marine animal with a trunk

Any schoolchild knows that trusting the "sea" names of animals is very reckless: sea lions have nothing to do with lions, seahorses have nothing to do with horses, and sea urchins have nothing to do with the hero of a famous cartoon who got lost in the fog. Elephant seals are no exception. In common with elephants, they have only outstanding sizes (these are the largest of marine mammals, not counting whales) and a long, movable nose resembling a trunk.

In fact, elephant seals living in the waters of the Arctic and Antarctic belong to the family of true seals, which is part of the order of predatory mammals. It is curious that 20 years ago it was written in biology textbooks that elephant seals, along with all other seals and walruses, constitute a separate order of mammals - pinnipeds (although many scientists have long expressed their doubts about this).

Since the taxonomy of biological species is built on an evolutionary basis, it was assumed that all pinnipeds have a common ancestor. But the successes of paleontology and genetics have convincingly proved that pinnipeds cannot be singled out as a separate order. It turned out that of the three families traditionally included in this order, two - eared seals and walruses - come from ancient bears, and the third - real seals - from martens. Moreover, even the transition to an aquatic way of life happened to them in different parts of the earth: the first "went into the water" on the Pacific coast, the second - in the Mediterranean Sea. And they became similar to each other only due to the same living conditions. So the closest terrestrial relatives of elephant seals are badgers, wolverines, martens and ferrets.

Manatees and dugongs have much more rights to be called elephant seals. They are indeed close relatives of elephants. But, ironically, their largest representative (alas, recently extinct) was called the sea, or Steller cow.

But back to our elephant seals. These animals are remarkable not only for their outstanding size, but also for the so-called sexual dimorphism, that is, a pronounced difference between males and females. According to this indicator, they seem to confidently take first place among mammals. Thus, male elephant seals often reach a length of 6.5 m and a weight of 3.5 tons, while females grow to a maximum of 3.5 m and 900 kg, respectively. If people had the same sexual dimorphism, then eighty-meter-tall boys would be walking down the street with their twenty-kilogram girlfriends less than a meter tall. No pins would help here.

With such differences, it is not surprising that the elephant seal herd is an all-male-dominated society. Strong adult males capture from a dozen (in the northern species) to a hundred (in the southern species) females into their harems and jealously protect them from the encroachments of their less fortunate rivals. Offering his hand and heart to the lady, the male puts his flipper on her back and gently bites her on the back of the head. However, if the lady is not in the mood, the male does not stop before the banal rape. Having pressed her with his carcass to the ground, he does everything that is necessary with his chosen one, not particularly interested in her consent. Elephant seals are one of the few representatives of the animal kingdom that practice domestic violence.

As for the "trunk" of the elephant seal, despite its external resemblance to a real elephant's trunk, it is not used as a working tool. The long nose is only found in males and is used to attract females and scare away other males. Firstly, it serves as a sound resonator: the roar of the elephant seal, like its land namesake, is heard for many kilometers. Secondly, during the mating period, due to the rush of blood to it, the nose swells and turns a little red, which, no doubt, should attract females, and at the same time demonstrate to other males who is the boss in the house. Therefore, in constant fights among themselves, males tend to primarily damage the opponent's trunk, often tearing it literally to shreds.

Elephant seals did not quite reach the championship title in such a sport as diving. According to reports, they dive for prey to a depth of almost one and a half kilometers! Of the mammals, only some whales dive deeper - up to two kilometers. The secret lies in the ability of elephant seals to control their blood circulation. When they are immersed in water, the blood supply to most muscles and internal organs is almost cut off, and oxygen from the blood goes only to the brain and heart. Therefore, elephant seals are able to linger under water for a long time.

Sea elephants ( Mirounga) is the largest genus in the family of true seals,. There are two types of elephant seals, named according to the hemisphere in which they live. northern elephant seals ( Mirounga angustirostris) are found in coastal waters around Canada and Mexico, and southern elephant seals ( mirounga leonina) are common off the coast of New Zealand, South Africa and Argentina.

Description

The oldest confirmed fossils of these animals date back to and they were discovered in New Zealand.

Only an adult male has a large trunk, similar to. The male uses it to roar during the mating season.

Southern elephant seals are slightly larger than northern ones. pronounced, males of both species are much larger than females. The average weight of an adult male of the southern species can be 3000 kg, and the body length can reach 5 m. An adult female weighs about 900 kg, and her body length is approximately 3 m.

The color of the animal depends on sex, age and season. It can be rusty, light or dark brown, or gray in color.

The elephant seal has a large body, short toed front flippers, and webbed rear flippers. Under the skin is a thick layer of fat that protects the animal in cold weather. Every year, elephant seals molt.

Average life expectancy is 20 to 22 years.

reproduction

Elephant seals are solitary animals. They return to established breeding colonies every winter. Females become sexually mature at the age of 3 to 6 years, and males - at 5-6 years.

However, males must reach alpha status to mate, which usually occurs between 9 and 12 years of age. Males fight each other using body mass and teeth. While deaths are rare, injuries are common. An alpha male's harem is between 30 and 100 females. Other males are found along the edges of the colony, sometimes mating with the females before the alpha males chase after them. Males stay on land during the winter to defend territory.

About 79% of adult females mate, but only more than half of them produce offspring. The gestation period lasts about 11 months, at the end of which one cub appears. The milk of a female contains an extremely high percentage of fat content, over 50% (compared to 4% fat content in female milk). Females do not eat for one month to feed the young. The next mating takes place during the last days of feeding.

Nutrition and behavior

Elephant seals are mammals. Their diet includes squid, octopus, eels, fish, krill, and sometimes. Males hunt at the bottom, while females hunt in the open ocean. Elephant seals use the sight and vibration of their whiskers to find food. They can attack sharks, killer whales and humans.

These animals spend about 20% of their lives on land and about 80% in the ocean. Although they are, elephant seals are capable of outpacing humans on land. In the sea, they develop a speed of 5-10 km / h.

Elephant seals can dive to great depths. Males spend more time underwater than females. An adult male is able to stay under water for about two hours and dive to a depth of about 2 km.

conservation status

Elephant seals were hunted for their meat, fur and fat. Poaching has brought the species to the brink of extinction. By 1892, most people believed that northern elephant seals were extinct. But in 1910, a single breeding colony was discovered near the island of Guadalupe off the coast of the Mexican state of Baja California. At the end of the 19th century, new marine conservation legislation was introduced to protect these animals. Today, elephant seals are no longer endangered, although they are at risk of becoming entangled in litter and fishing nets, and may be injured in collisions with watercraft. The IUCN lists them as Animals of Least Concern.

• Scientists have determined that at warm water temperatures, more males are born than females.
• The screech of orcs in the mines of Moria in The Lord of the Rings: The Fellowship of the Ring was the sound of baby elephant seals.
• In 2000, a male elephant seal named Homer terrorized the New Zealand city of Gisborne. Homer attacked cars, boat trailers, trash cans, trees, and even a transformer.

Thoughtless human activity almost ruined one of the curious species of animals - the sea elephant. They got their name not only for their huge size (these animals but also for a kind of nasal growth. Thick and fleshy, it looks like an underdeveloped trunk. It is not used as a hand, like a real land elephant, but “works” as a resonator organ, several times amplifying the sound of the roar.He also shows the surrounding relatives how formidable and powerful his master is.

Description

The elephant seal belongs to the pinnipeds, a family of true seals. They surpass even walruses in size and are the largest in their class of predators. They are distinguished by heavy build, very coarse skin, covered with fur. Fat can be up to 30% of an elephant's live weight. Sexual dimorphism is very pronounced - the size of males significantly exceeds the size of females. Another difference is that females do not have a trunk. Two types are known: northern and southern.

The elephant seal dives perfectly, can hold its breath for up to 2 hours and descend to a depth of almost two kilometers. The speed of its movement in water is up to 23 km / h. They feed on fish, molluscs, plankton, and cephalopods. Among the main enemies (except humans) are killer whales and large sharks. No one threatens them on the shore, so they are very careless and can afford to sleep soundly, often with loud snoring. On land, they move with difficulty, pulling their carcass up on their front flippers. For one such "throw" animals cover a distance of no more than 35 cm.

Females reach sexual maturity by 3-4 years, males at 6-7 years. The breeding season is once a year. It begins with the fact that adult (from 8 years old) males are the first to swim to the places of the rookery and occupy parts of the beach. Then the females pull themselves up and, entering the “conquered” territory, automatically become members of the harem. There are sometimes up to 50 females per elephant (usually within 20). Fights for females can be very violent. During a tense duel, the elephant seal rises to its full gigantic height, keeping the body in an upright position on one tail. Young males (up to 8 years old) usually live on the periphery of the haulout and do not try to argue with the harem owners.

Pregnancy lasts 11 months. Usually, childbirth begins in females 5-6 days after arrival on shore. Newborn cubs feed exclusively on mother's milk for 4-5 weeks. They are born weighing up to 50 kg, up to 120 cm long. A month later they move to the outskirts of the haulout and after molting, at the age of 3-4 months, they go to the sea. Females after feeding babies are ready for mating.

Southern

Animal sizes: males - 6 meters in length, weight up to 4 tons, females are three times smaller. The southern elephant seal (photo in the text) has its own peculiarity: it has a clear separation between haulouts. Some are used as "maternity wards", others a few hundred kilometers away - for feeding. Islands - breeding grounds:

• Kerguelen.
• Campbell.
• Crozet.
• Macquarie.
• Morion.
• Fire Earth.
• Auckland.
• Prince Edward.
• Falkland.
• Hurd.
• South Georgia.
• South Orkney.
• Southern Sandwiches.
• South Shetland.

The mating season is September-November. To date, the total number of animals is up to 700,000 heads.

Northern

The northern relative in style of life differs little. Mating takes place in February. It has permanent rookeries, where the sea elephant swims for breeding and for the molting period. The mainland (west coast of North America) from Mexico to Canada with pebble beaches or gently sloping rocky shores has long been chosen by water giants. It is inferior in size to its southern brother, males grow up to 5 meters, their weight fluctuates within 2.5 tons. They have a large trunk up to 30 cm, in an excited state it increases to 70 cm. Females weigh up to 900 kg, body length up to 3.5 meters.

It was the northern elephant seals that took the brunt of the extermination. After tough measures to ban fishing, their population has grown to 15 thousand individuals today. Not bad at all, considering there were about a hundred of them left.

Elephant seals are mammals that belong to the class of pinnipeds. They can be compared with seals, they are very similar. The difference is only in size, elephant seals are larger, as well as in a process of skin up to 30 cm long in the nose area, which is considered to be a trunk. That's why elephant seals were called that - because of this trunk.

Where do sea elephants live?

Elephant seals live in the southern hemisphere of the earth, they prefer subantarctic climatic zones, but these mammals can also be found in the arctic zones. Popular sites for elephant seal colonies are Heard and McDonald Islands, South Georgia, Prince Edward, Crozet, the Kerlegen Archipelago, and some peninsulas and islands of Western Antarctica.

What is unique about the elephant seal?

1. The sea elephant is considered the largest predator in the world. Its diet consists of squid, sometimes fish and krill.
2. Spend in water up to 300 days a year. The remaining 2-3 weeks, elephant seals find a rookery on the beaches near the coast for mating and breeding.
3. During their stay in the water, elephant seals cover a distance of up to 13 thousand kilometers, making daily dives into the water up to 700 meters, but there have been cases of diving up to 2000 meters.
4. The maximum stay under water of a sea elephant is registered - this is 120 minutes.
5. The blood of elephant seals is saturated with oxygen, which makes it possible for them to make such long swims and dives. Yes, and the blood itself makes up a fifth of the entire body weight of a mammal (this is 2-3 times more than in humans).
6. The body length of males can vary from 4 to 6 meters, their body weight is 3-5 tons. And the body length of the female is much less - from 2.5 to 3 meters, body weight - up to 1 ton.
7. Baby elephant seals are called puppies. Puppies are born quite large. Their body length at birth can be 125 cm and weight up to 50 kg.
8. The number of elephant seals in the world is about 800 thousand individuals, more than half of them live on the island of South Georgia.
9. The organization of the mating process of these mammals is similar to a harem. The strongest males regularly fight for their right to become the "master of the harem" with other males. Only a third of the males have the opportunity to get to the females.
10. Elephant seals move on land a little clumsily due to their large weight. When moving, the front flippers are used, but most of the weight is transferred to the back of the animal's body. In water, on the contrary, they feel harmonious and look very graceful.
11. The average life expectancy of males is 18-20 years, and that of females is 12-14 years.

The process of mating or mating games of sea elephants

Elephant seals live alone during swimming and only 2-3 summer months these mammals spend on land, gathering in large groups for rest and reproduction. The size of such a group can reach 400 thousand individuals. The reproduction of these mammals occurs exclusively on land. Females become ready for reproduction and mating at the age of 2-3 years, males become sexually mature later: at 4-7 years.

When entering land, all sexually mature females gather in one heap and form the so-called harem, where only selected males have the right to enter. Every male who wants to get into the society of females must defend his right to reproduce. Males emit a long roar and begin their battles among themselves. These battles are sometimes cruel and consist in the fact that one of the males drives another male out of his territory. In this battle, the size, weight and of course the age of the mammal play an important role.

After the victory, the male goes to the females and gets the opportunity to copulate with them. Only a third of all males can be honored with this honor. One male can mate with a large number of females: from 20 to 300 individuals, sometimes even up to a thousand females.

On average, 2-3 months after arriving on land, females have puppies. When puppies are three weeks old, they shed. The black fur that covered their body changes to a gray fur skin.

While feeding the puppies with milk, the female does not leave them even to catch food for herself. Feeding puppies can last up to 4 weeks.

In the 19th century, elephant seals were on the verge of extinction.

Indeed, in the 19th century, elephant seals were openly hunted, they were the object of hunting because of the subcutaneous fat that was extracted from their bodies. Especially a lot of large males were exterminated at that time, because of which the birth rate of puppies also decreased.


The extermination of sea elephants took place in a barbaric way. Animals were stabbed with a spear on the shore, they were not allowed to reach the water, and even burning torches were thrust into their mouths. And all this for the sake of a layer of subcutaneous fat, which in elephant seals can reach a thickness of 15 cm.

But starting in 1964, the ban on hunting elephant seals came into force. The International Convention for the Conservation of Antarctic Seals has been established to protect the rights of elephant seals and other pinnipeds.

Elephant seals are pinnipeds from the true seal family. In their order, these animals are the largest and exceed the size of the well-known walruses. The closest relative of elephant seals is the hooded seal, with which they have common features. In total, there are 2 types of elephant seals - northern and southern.

Male northern elephant seal (Mirounga angustirostris).

Sea elephants got their name not by chance, they are animals of really gigantic sizes. The body length of the male southern elephant seal can reach up to 5 m, weight up to 2.5 tons! Females are much smaller and reach a length of “only” 3 m. Elephant seals differ from the rest of the seals in their overall weight and a large amount of subcutaneous fat. The weight of the fat layer can be 30% of the total weight of the animal.

Penguins next to the southern elephant seal give an idea of ​​the size of this animal.

In addition to their size, elephant seals have another feature that makes them look like real elephants. The males of these animals have a thickened fleshy outgrowth on the nose, similar to a short trunk. During the mating season, the trunk is used for decoration, intimidation and as a resonator that enhances the formidable roar.

Male northern elephant seal during mating.

The females do not have a trunk.

The female northern elephant seal.

The skin of elephant seals is thick and rough like that of a walrus, but covered with short thick fur like that of real seals. Mature elephant seals are brown in color, while young ones are silver-gray.

Young southern elephant seal (Mirounga leonina).

Geographically, both species are also separated: the southern elephant seals live on the coast of Patagonia and the subantarctic islands, while the northern ones live on the west coast of North America - from Mexico and California to Canada. Both species prefer to settle on pebbly beaches and gently sloping rocky coasts. Elephant seals, unlike other seals, form rather large rookeries, numbering up to a thousand individuals.

Female southern elephant seal on a rookery.

Interestingly, southern elephant seals have two types of rookeries - for breeding and for feeding. Feeding rookeries are several hundred kilometers away from the "maternity hospitals", so elephant seals regularly migrate. These animals feed mainly on cephalopods, less often on fish. In general, elephant seals are quite calm and even apathetic animals. Due to their heavy weight on land, they are clumsy and sluggish.

The breeding season occurs only once a year and begins in August-October (in the Southern Hemisphere it is spring). Sexually mature males and females are the first to arrive at the maternity rookeries, the young come a little later. During the mating season, males are transformed beyond recognition. If at normal times they just sleep on the shore, then during the rut they lose their peace and sleep. Each male occupies a certain area of ​​the beach and does not allow other males to enter it. When the competition grows, the opponents converge in a fierce battle. They roar loudly, puff out their noses and shake them funny in the air to intimidate the enemy. But it looks funny only to an outside observer, because the males themselves in fights bite each other to the point of blood and often inflict severe injuries on the opponent.

Male southern elephant seals in a bloody duel.

And the thing is that every female entering the territory of the male becomes his chosen one and mates with him (unless, of course, she is beaten off by an opponent). So males form around themselves harems of 10-30 females. Pregnancy lasts 11 months, so childbirth and mating occur almost simultaneously. Females give birth to one large cub, the “baby” weighs 20-30 kg! Baby elephant seals are born black. Mothers feed them with milk for a little more than a month, after which the young move to the periphery of the haulout and do not enter the water for several more weeks. All this time, the cubs live off the reserves of subcutaneous fat accumulated during feeding with milk. After some time, the animals molt, after which they leave the breeding grounds.

Sea elephant during molting.

Despite their large size, many elephant seals (especially young ones) die in the mouths of killer whales and sharks. Sometimes males die from wounds and general exhaustion during the rut, moreover, adult males often crush cubs in the cramped haulout. In general, these animals are not very prolific, moreover, their numbers have been greatly undermined by fishing. Previously, hunting for elephant seals was carried out for the sake of rendered fat (up to 400 kg from one male!), Meat and skins. Now the fishery has already been stopped, but the number of northern elephant seals is still low.

Yawning sea elephant.