In our age, when humanity has penetrated into space and we are eager to find at least some living organisms on Mars or other planets, we can’t help but wonder: are we really familiar with our earthly brethren? How much do we know about them? Do we know their way of life? Needs? Behavior? Relationships with the outside world?
You don't have to look far for examples. How many of us have seen a live elephant seal? Of course, almost everyone knows that such animals exist. But few people were lucky enough to see natural conditions these giants, exceeding the size and weight of rhinoceroses, hippos and walruses. Elephant seals live in remote places, namely: in Patagonia - off the coast of Argentina, on the Macquarie Islands - south of Tasmania, on Signy Island, on South Georgia.
To begin with, let's say that these are huge pinniped mammals belonging to the genus of earless seals (Phocidae), named so in contrast to eared seals— Otariidae. The length of males is from three to six meters, and such a colossus weighs up to two tons! In body shape, these giants resemble walruses, and their skin is just as thick and hard, but they do not have walrus tusks, but they do have something like a short thick trunk (which is what elephant seals owe their name to). Very few of these amazing animals have survived to our time. And if we hadn’t realized it at the last moment, they would have completely disappeared from the face of the Earth, like their close relatives - the sea cows, discovered by naturalist Georg Steller in 1741, during an expedition in the Bering Sea. Having described these huge, harmless herbivores, which were easy to shoot thanks to their slowness and gullibility, Steller involuntarily showed the way to easy prey for various enterprising people. By 1770, sea cows (later called Steller's cows) no longer existed.
Fortunately, this did not happen to elephant seals. Primarily because they live in areas that are difficult for humans to reach: or they swim in icy water polar seas the southern hemisphere, where, in addition, sharp storm winds never subside, or they briefly go to their rookeries located on the deserted rocky shores of Patagonia or on small islands lost in the ocean. In addition, elephant seals, unlike their harmless relatives - dugongs, or sirens, peacefully nibbling sea grass in underwater “meadows”, are by no means defenseless animals. Especially the males. Their teeth are sharp and their strength is enormous. An adult male can be quite aggressive. Elephant seals- predators: they feed on various aquatic animals, mainly fish.
There are two types elephant seals: northern (Mirounga angustirostris) and southern (Mirounga leonina). Northern view, differing from the southern one in being narrower and long trunk, lives in California and Mexican waters. Due to predatory fishing in the last century, this species almost completely disappeared. By 1890, only about a hundred northern elephant seals remained, and only the ensuing the strictest ban fishing allowed them to increase their numbers again. In 1960 there were already fifteen thousand of them.
Herds were also subjected to merciless extermination southern species, whose former vast range is now limited to only a few Antarctic islands, such as Kerguelen, Crozet, Marion, and South Georgia. Several rookeries have also survived on Macquarie and Heard Islands. However, in temperate zone, where previously there were also rookeries of these animals - for example, on the southern coast of Chile, on King Island near Tasmania or on the Falkland Islands and Juan Fernandez Island - now you will not see a single one...
Today, elephant seals can be said to have somewhat recovered from past shocks. In some places they have even restored their former numbers. But this, of course, is only where the animals are strictly protected, for example on the Argentine Valdez Peninsula, declared a protected area, or on the Macquarie or Heard Islands, where hunting them has been prohibited for forty-five years. The animals there are clearly thriving, and their numbers are growing year by year. As for islands such as South Georgia and Kerguelen, part of the herd is still shot there from time to time. True, it is claimed that they do this under strict scientific control.
Why were elephant seals so attractive to fishermen? These animals were hunted for their subcutaneous fat alone. Its layer reaches a thickness of fifteen centimeters! The animal needs it to protect it from heat loss in the icy water in which it spends most of its life. And it was this fat that turned out to be so attractive. For his sake, elephant seals were mercilessly killed, whole mountains of their carcasses towered along the shores, and right there on the shore, fat was melted out in huge vats specially installed for this purpose... On the Patagonian coast of Argentina alone, from 1803 to 1819, North American, English and Dutch fishermen drowned a total of one million seven hundred and sixty thousand liters of “elephant fat”. This means that the number of animals killed for this purpose reached no less than four to six thousand! They killed them in the most barbaric way: they cut off the path to saving water and stabbed them with spears or shoved burning torches into their open mouths...
And now, on the shores of many islands of Patagonia, these huge vats and other equipment for rendering fat are lying around, rusting in the salty sea wind... These abandoned vats seem to personify the sad memory of the thoughtless and irresponsible exploitation of nature by man in the recent past and serve as a warning to future generations...
And now, when people have stopped killing elephant seals, the time has come to study them. Several groups of scientists from different countries are doing this. Very successful observations of the life of these giants were carried out on the islands of Signy and South Georgia by English biologists under the leadership of Dr. R. M. Loves from the British Antarctic Survey; at the same time, Australian scientists, led by Dr. R. Carrick, were working on Macquarie and Heard Islands. The results of their research were published in Canberra in 1964. Somewhat later, the famous English zoologist John Warham conducted observations on the same islands.
What did you manage to find out about this rare and little-studied animal?
Despite its colossal size, the elephant seal is a good swimmer. This is facilitated by the spindle-shaped shape of its body. The elephant seal is capable of swimming at speeds of up to twenty-three kilometers per hour. Moreover, in icy water reliable protection against the cold he wears a kind of “quilted jacket” - a thick layer of subcutaneous fat. In the water, this heavy animal shows extraordinary maneuverability and dexterity: after all, here it has to get its food by chasing fish, looking for accumulations of plankton and various crustaceans. The elephant seal is much less suited to living on land, although it has to spend a good quarter of its life there. It’s hard to imagine a slower and more clumsy animal here! He painfully drags his heavy body along the rocky soil, moving with only his front flippers. At this time, it resembles a huge snail or caterpillar: one “step” for an elephant seal is only thirty-five centimeters! Own weight, so invisible in water, on land it becomes an unbearable burden for the animal. It is not surprising that the elephant seal quickly gets tired from exertion, lies down and immediately falls asleep in a rich, uninterrupted sleep. The elephant seal's sleep is truly uninterrupted - in any case, it is not so easy to wake it up. This is explained by the fact that for a very long time these giants had no enemies on land, and they, like rhinoceroses, had no one to fear and no need to sleep lightly.
The deep sleep of elephant seals repeatedly surprised the English zoologist John Warham, who carried out his observations on Macquarie Island. Every morning, leaving his tent, he came across elephant seals lying sideways in front of the door and blocking his path. These were all molting young males ranging from three to four and a half meters long. They slept completely serenely, their breathing was deep and noisy, sometimes even turning into loud snoring. However, it didn’t take much effort for the researcher to get over them: he walked right on their backs, and by the time these bumpkins realized that they had been walked on in forged boots (which made them raise their heads in fear), the troublemaker was already far away...
No less amazing is the ability of elephant seals to sleep underwater. But how do animals manage to breathe at this time? After all, they have lungs, not gills!.. Scientists managed to figure out the secret of such underwater sleep. After five or ten minutes under water, the animal’s chest expands, but the nostrils remain tightly closed. As a result, the density of the body decreases and it floats up. At the surface of the water, the nostrils open and the animal inhales air for about three minutes. Then it sinks to the bottom again. The eyes remain closed all this time: the elephant is clearly sleeping.
Stones are commonly found in the elephant seal's stomach. Residents of the places where these animals live believe that the stones serve as ballast while the elephants dive under water. There are other explanations. For example, stones in the stomach can contribute to the grinding of food - whole swallowed fish and crustaceans.
Elephant seals feed mainly on fish, and not cuttlefish, as was previously thought. Cuttlefish in their “menu” is no more than two percent. But an adult elephant seal eats a lot of fish. According to the famous zoologist Hagenbeck, the five-meter Goliath elephant seal kept in his menagerie ate an average of fifty kilograms of fish per day! Messages of this kind have led some ichthyologists to argue that the disappearance of elephant seals is a good thing, because they allegedly disputed the fishermen’s catch... However, careful research has shown the absurdity of such conclusions: elephant seals feed mainly on small sharks and rays that are not listed commercial fish... On land, during the breeding season, elephant seals are able to fast for weeks: during this time they do not eat anything, but live off their internal fat reserves.
Careful study of these animals in recent years has lifted the curtain on many of the secrets of their life and behavior. In some ways, these clumsy colossi turned out to be quite a convenient object for the researcher: it didn’t cost anything, for example, to measure their length, calculate the number of individual herds, their composition, age groups, observe the “family” life of these animals, the birth of young animals, etc. d. But try weighing such a huge thing! After all, after all, a male who has reared up (and this is their usual pose of threat) becomes as tall as a good column, and even the sight of just one photograph of such a giant is awe-inspiring. Where can we even think about grabbing him and throwing him on the scales!.. No, studying such animals is not an easy task, and you have to be a real enthusiast to take it on. After all, we must not forget about climatic features places where these observations are made: about continuous prickly winds, icy water, bare, inhospitable rocky landscape... And yet the researchers managed to conduct very important work, which made it possible not only to determine the age of individual individuals, but also to trace their migrations, seasonal changes herd composition, molting process, relationships in the herd.
But let's start in order. For four years, Australian researchers on Heard and Macquarie Islands systematically branded elephant seal pups, much like domestic calves or foals. By 1961, nearly seven thousand elephant calves had been tagged. This subsequently made it possible to accurately determine the age of a particular animal, the order in which different age groups appear at the rookery, the attachment of individual individuals to their “homeland” or the tendency to change places... Thus, the female number “M-102” for four years in a row gave birth to offspring in the same place and only in the fifth year moved half a kilometer further. Other patterns also emerged. For example, “teenage” groups of elephant seals appear at the rookery much later than adults participating in breeding, which usually occurs from August to mid-November. Shedding in animals of different age groups also occurs in different time. Thus, the rookery is almost never empty - only the contingent of its inhabitants changes.
Among the males, four groups can be clearly distinguished. The first - “teenage” - includes animals aged from one to six years, their size does not exceed three meters. They appear at the rookery in winter, especially after storms, with the obvious purpose of taking a break from swimming. These animals appear before anyone else to molt - in December (the beginning of summer in the southern hemisphere), and then all other animals appear in order of seniority: the older in age, the later.
The second, or “youthful” group is formed by animals aged from six to thirteen years, their size is from three to four and a half meters. They swim to the beach in the fall, soon after the females give birth to their cubs, but they do not engage in fights with older males and swim out to sea even before the start of the rut (after the cubs are weaned).
Next age group- the so-called contenders. Such males, measuring from four and a half to six meters, with a proudly inflating trunk, are in a constantly aggressive mood and try to fight with the owners of the rookery - the owners of the “harems” - powerful old males, trying to take away some of the females from them. These old, experienced males make up the fourth age group.
Such a “harem” owner is a very impressive figure. He is huge, imposing, jealous and aggressive. If he had been different, he would not have held his “post.” After all, a “harem” usually consists of several dozen females, and in order to keep all these curious beauties in obedience, trying to scatter in different directions and “flirtying” with every “contender” that appears, you need remarkable strength and a vigilant eye... Seeing a rival, the owner “ harem" emits an angry roar and rushes towards him, destroying everything that gets in the way: knocking over females and trampling cubs... Such a "master" is generally, as a rule, an extremely "insensitive" animal. It often happens that he crushes newborn cubs to death. A case is described when a male went to bed, crushing a desperately screaming cub under him, but did not even think of getting up to free the unfortunate one.
If the “harem” turns out to be too large for one owner, he is forced to allow “assistants” into his territory, guarding its remote areas...
Observations have shown that the same old and strong male dominates the “harem” throughout the entire breeding season, and younger and weaker males are often forced to give up their place to a rival that is superior in strength. Although male fights usually take place in the water, not far from the shore, panic also begins on the beach at this time - alarmed females scream, the cubs try to escape. Therefore, from “harems” where they are too often disturbed, females try to move to calmer “harems”.
The fight between males is an impressive sight. The rivals, having swam up to each other, rear up, rising about four meters above the shallow water, and freeze in this position for several minutes, reminiscent of stone sculptures of monsters. The animals emit a dull roar, their trunks swell menacingly, showering the enemy with a cascade of spray. After such a performance, the weaker enemy usually retreats backwards, continuing to roar threateningly, and, having moved to a safe distance, takes off running. The winner lets out a proud cry and, after making several false throws after the fugitive, calms down and returns to the beach.
When none of the opponents is going to concede, the battle flares up in earnest. Then both powerful bodies they loudly hit each other, with a quick and sharp movement of their heads, each tries to sink their fangs into the opponent’s neck. However, the skin of the elephant seal is so hard and slippery, and also equipped with a thick cushion of subcutaneous fat, that serious injuries rarely occur. True, scars and scars remain on the neck of males for life, but that’s all.
No matter how terrifying such a battle may look from the outside, in most cases it does not lead to serious bloodshed. Usually everything is limited to mutual intimidation, terrifying roars and sniffles. The biological meaning of this behavior is clear: the strongest is identified, who will take on the functions of a producer during the mating season and, as a continuer of the clan, will pass on his offspring to his offspring. positive traits. At the same time, the weaker young male does not die on the battlefield and thus is not excluded from the further process of reproduction of the species...
When individual plots and “harems” have already been distributed, there are practically no battles between male neighbors: if someone violates territorial integrity, it is enough for the “master” to rise up and growl for the border violator to immediately leave.
Tall males do not always show aggressiveness towards humans. And it is not they, but the females that may turn out to be the most dangerous for a researcher who dares to penetrate into the very thick of the herd. John Warham, for example, more than once had to get acquainted with their sharp teeth and run away shamefully, leaving a good piece of his trouser leg as a souvenir for the angry elephant seal...
It is worth telling more about the females. Females are significantly smaller than males - they rarely reach three meters in length and a ton of weight. They grow slowly, but physically develop faster than males: by two to three years they become sexually mature, while males reach sexual maturity much later.
The breeding season lasts from August to mid-November. Females appear at the rookery already “during pregnancy” and within five days they bear offspring. Most babies will be born from late September to mid-October. Owners of “harems” vigilantly guard the females during the period of birth of offspring.
Both females and males arrive at the beach well-fed after fattening up thoroughly at sea. This is necessary for the long “fast” that they have to endure on land: males “fast” for up to two weeks, and females even for a whole month! But during this time, the females will have to endure all the hardships associated with childbirth and feeding the cubs, and the males will have to endure the stress of the subsequent mating season and the associated fights with rivals.
Having appeared on the beach and preparing for childbirth, the females are located at some distance from each other, and do not lie closely side by side, as in normal times. The birth itself lasts only about twenty minutes, and the baby is born sighted. Moreover, he is very pretty: covered with wavy black fur and looking at the world huge radiant eyes. But the “baby” weighs about fifty kilograms, and reaches a length of one and a half meters, that is, the size of an adult seal...
Having been born, the cub emits a short bark, reminiscent of a dog, and the mother responds in kind, sniffs it and thus remembers it. Subsequently, she will unmistakably distinguish him among many other cubs and will be able to return him if he tries to escape.
The upcoming birth can be immediately determined by the fact that loud, large brown birds, called skua in some areas, are circling above the woman in labor. These birds work as “midwives” for elephant seals. With extraordinary agility they remove birth membranes and placenta, and on occasion they can even cope with a stillborn baby. Skua is not averse to treating herself to the milk of nursing females spilled on the ground.
This milk is unusually nutritious (almost half consists of fat), and the cubs grow with unprecedented speed: they gain from five to twelve kilograms per day! In the first eleven days they double their weight, and in two and a half weeks they triple it. They gain length, albeit a little, but they build up an impressive layer of fat - seven and a half centimeters, which they will need first of all: it should protect their body from hypothermia during the upcoming long stay in the water.
After about a month, the females stop feeding the cubs, or “kochoro” as they are called in Patagonia. By this time, their “baby” black fur has been replaced by silver-gray, and they look very well-fed and happy. Soon they leave the “harem”, crawling deeper into the beach, where they rest and build up their muscles. At the age of five weeks, the young begin their first timid attempts at swimming. On quiet, windless evenings, baby elephant seals clumsily descend into the sun-heated water of lagoons or the remaining basins after low tide and carefully swim near the shore. Gradually they become more confident and bolder, they venture on longer sea excursions, until, at nine weeks old, they finally leave their native rookery and swim off into the distance...
And again, one can only be amazed at how intelligently everything is arranged in nature. The young become independent precisely at the period when the prospects for their survival are most favorable. Just at this time, the surface of the sea is covered with a particularly thick layer of plankton, and young elephant seals are provided with easily accessible and high-calorie food for several months.
However, control over marked animals showed something else: half of the cubs die in the first year of their life. Later, losses are significantly reduced, and approximately forty percent of the young animals reach four years of age.
Based on these data, Australian experts came to the following important conclusions. If it is necessary to shoot some part of the elephant seal herd (due to overcrowding of the rookery, lack of food, etc.), then it should be young animals aged from five weeks to one year. But it is completely unacceptable to shoot adult males, as was once practiced in South Georgia, where about six thousand of them were once killed in one summer. Without proper protection of the “harems” by old, experienced males, the herds decline, because young males begin to wage continuous battles with each other, challenging primacy. This is what incompetent human intervention in the affairs of nature leads to and therefore we must avoid rash actions without sufficient scientific justification.
But let's return to the elephant seal rookery, from where the young have just departed. After the “weaning” of the cubs, the females mate again with the owner of the “harem” and soon after that they go to sea - to take a break from the hardships of childbirth, to eat well and build up new layer fat until its next appearance at the rookery - in February, during the molting period.
And here we should mention one of the most amazing adaptations of the animal body to the conditions of existence: the development of the embryo in the womb of the female is temporarily suspended, and the embryo is, as it were, “preserved” for the entire unfavorable period of the animal’s life - in this case, during molting. (A similar phenomenon is observed in some other animals - many pinnipeds, as well as in sable, rabbit, kangaroo, etc.) The development of the embryo continues only in March, when the molting of females is already completed.
Powerful males, the owners of the beach, show up to molt much later - around the beginning of April. Intense life at the rookery requires longer recuperation.
As already mentioned, the younger ones appear first, and later the older ones. During molting, age groups stay together, but according to gender: females with females, and males with males. Molting lasts, depending on age, one to two months. Until it is completely over, animals will never set sail, because at this time they are sensitive blood vessels the skin is greatly expanded and sudden cooling can cause disruption of the thermoregulation mechanism, which means inevitable death in icy water.
The molting elephant seal looks most deplorable: its old skin hangs on it in torn rags. First it comes off the muzzle, and then from the rest of the body. At the same time, the poor creatures scratch their sides and stomach with their flippers, trying to speed up this obviously unpleasant process for them...
Shedding animals usually settle down in some moss-covered swamp, not far from the shore, and, restlessly tossing and turning, stir up the loose soil, turning it into a dirty mess. They plunge into it up to their nostrils. The stench around at this time is terrifying. So not every tourist is able to withstand it... By the way, about tourists visiting protected places. As already mentioned, the Argentine government has declared the small Valdez Peninsula in northern Patagonia a protected area. A colony of elephant seals, numbering several hundred heads, settled on this peninsula. It is called “elephantery” (elephant colony), and recently access has been opened to visitors. One hundred and sixty-five kilometers from the rookery, the resort town of Puerto Madryn arose. And since the water here is often too cold for swimming, many vacationers willingly take excursions to the “elephanteria”. They offer paid tour guides. In addition, the tourist route, which runs through a number of South American countries, includes a visit to the Valdez Peninsula with its elephant seal rookery. The ever-increasing flow of tourists, loudly expressing their delight and constantly clicking cameras, certainly unnerves the animals and disrupts their usual way of life, especially at a time when females give birth. The males who own the “harems” here began to behave much more aggressively than usual. They angrily rush towards annoying visitors, trying to drive them away from “their” territory, or drive their entire “harem” into the water...
There are 2 species in the genus:
southern elephant seal - M. leonina Linnaeus, 1758 (subantarctic waters circumpolar north to 16° S and south to Antarctic pack ice - 78° S; breeds near Punta Norte and Tierra del Fuego in Argentina and on islands of Falkland, South Shetland, South Orkney, South Georgia, South Sandwich, Gough, Marion, Prince Edward, Crozet, Kerguelen, Heard, Macquarie, Auckland, Campbell);
northern elephant seal - M. angustirostris Gill, 1866 (islands off the coast of Mexico and California north to Vancouver and Prince of Wales islands; breeds on San Nicolas, San Miguel, Guadalupe and San Benito islands).
The northern elephant seal was recently close to extinction due to overfishing, but Lately Thanks to the ban on fishing, its numbers have increased significantly and continue to increase.
The total number of southern elephant seals is estimated at 600-700 thousand heads, and the northern ones - only 10-15 thousand heads.
Southern elephant seals are hunted on coastal haulouts, and there are restrictions on fishing according to seasons, the size of seals harvested, at least 3.5 m in length, and their number. For example, in 1951 it was allowed to kill 8 thousand elephant seals; harvested 7877. Fat and skin are obtained from hunted animals.
November 7th, 2013
In our age, when humanity has penetrated into outer space and we are eager to find at least some living organisms on Mars or other planets, we can’t help but wonder: are we properly familiar with our earthly brothers? How much do we know about them? Do we know their way of life? Needs? Behavior? Relationships with the outside world?
You don't have to look far for examples. How many of us have seen a live elephant seal? Of course, almost everyone knows that such animals exist. But few people are lucky enough to see these giants in natural conditions, exceeding the size and weight of rhinoceroses, hippos and walruses. Elephant seals live in remote places, namely: in Patagonia - off the coast of Argentina, on the Macquarie Islands - south of Tasmania, on Signy Island, on South Georgia.
So what are these elephant seals like?
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To begin with, let's say that these are huge pinniped mammals belonging to the genus of earless seals (Phocidae), named so in contrast to the eared seals - Otariidae. The length of males is from three to six meters, and such a colossus weighs up to two tons! In body shape, these giants resemble walruses, and their skin is just as thick and hard, but they do not have walrus tusks, but they do have something like a short thick trunk (which is what elephant seals owe their name to). Very few of these amazing animals have survived to our time. And if we hadn’t realized it at the last moment, they would have completely disappeared from the face of the Earth, like their close relatives - the sea cows, discovered by naturalist Georg Steller in 1741, during an expedition in the Bering Sea. Having described these huge, harmless herbivores, which were easy to shoot thanks to their slowness and gullibility, Steller involuntarily showed the way to easy prey for various enterprising people. By 1770, sea cows (later called Steller's cows) no longer existed.
Fortunately, this did not happen to elephant seals. Primarily because they live in areas difficult for humans to reach: they either swim in the icy water of the polar seas of the southern hemisphere, where, in addition, sharp storm winds never subside, or they briefly go to their rookeries located on the deserted rocky shores of Patagonia or on small lost in the ocean islands. In addition, elephant seals, unlike their harmless relatives - dugongs, or sirens, peacefully nibbling sea grass in underwater “meadows”, are by no means defenseless animals. Especially the males. Their teeth are sharp and their strength is enormous. An adult male can be quite aggressive. Elephant seals are predators: they feed on various aquatic animals, mainly fish.
There are two species of elephant seals: northern (Mirounga angustirostris) and southern (Mirounga leonina). The northern species, which differs from the southern one in having a narrower and longer trunk, lives in Californian and Mexican waters. Due to predatory fishing in the last century, this species almost completely disappeared. By 1890, only about a hundred northern elephant seals remained, and only the strict ban on fishing that followed allowed them to increase their numbers again. In 1960 there were already fifteen thousand of them.
Herds of the southern species were also subjected to merciless extermination, the former vast range of which is now limited to only a few Antarctic islands, such as Kerguelen, Crozet, Marion, and South Georgia. Several rookeries have also survived on Macquarie and Heard Islands. However, in the temperate zone, where previously there were also rookeries of these animals - for example, on the southern coast of Chile, on King Island near Tasmania or on the Falkland Islands and Juan Fernandez Island - now you will not see a single one...
Today, elephant seals can be said to have somewhat recovered from past shocks. In some places they have even restored their former numbers. But this, of course, is only where the animals are strictly protected, for example on the Argentine Valdez Peninsula, declared a protected area, or on the Macquarie or Heard Islands, where hunting them has been prohibited for forty-five years. The animals there are clearly thriving, and their numbers are growing year by year. As for islands such as South Georgia and Kerguelen, part of the herd is still shot there from time to time. True, it is claimed that they do this under strict scientific control.
Why were elephant seals so attractive to fishermen? These animals were hunted for their subcutaneous fat alone. Its layer reaches a thickness of fifteen centimeters! The animal needs it to protect it from heat loss in the icy water in which it spends most of its life. And it was this fat that turned out to be so attractive. For his sake, elephant seals were mercilessly killed, whole mountains of their carcasses towered along the shores, and right there on the shore, fat was melted out in huge vats specially installed for this purpose... On the Patagonian coast of Argentina alone, from 1803 to 1819, North American, English and Dutch fishermen drowned a total of one million seven hundred and sixty thousand liters of “elephant fat”. This means that the number of animals killed for this purpose reached no less than four to six thousand! They killed them in the most barbaric way: they cut off the path to saving water and stabbed them with spears or shoved burning torches into their open mouths...
And now, on the shores of many islands of Patagonia, these huge vats and other equipment for rendering fat are lying around, rusting in the salty sea wind... These abandoned vats seem to personify the sad memory of the thoughtless and irresponsible exploitation of nature by man in the recent past and serve as a warning to future generations...
And now, when people have stopped killing elephant seals, the time has come to study them. Several groups of scientists from different countries are doing this. Very successful observations of the life of these giants were carried out on the islands of Signy and South Georgia by English biologists under the leadership of Dr. R. M. Loves from the British Antarctic Survey; at the same time, Australian scientists, led by Dr. R. Carrick, were working on Macquarie and Heard Islands. The results of their research were published in Canberra in 1964. Somewhat later, the famous English zoologist John Warham conducted observations on the same islands.
What did you manage to find out about this rare and little-studied animal?
Despite its colossal size, the elephant seal is a good swimmer. This is facilitated by the spindle-shaped shape of its body. The elephant seal is capable of swimming at speeds of up to twenty-three kilometers per hour. Moreover, in icy water, a kind of “quilted jacket” - a thick layer of subcutaneous fat - serves as reliable protection from the cold. In the water, this heavy animal shows extraordinary maneuverability and dexterity: after all, here it has to get its food by chasing fish, looking for accumulations of plankton and various crustaceans. The elephant seal is much less suited to living on land, although it has to spend a good quarter of its life there. It’s hard to imagine a slower and more clumsy animal here! He painfully drags his heavy body along the rocky soil, moving with only his front flippers. At this time, it resembles a huge snail or caterpillar: one “step” for an elephant seal is only thirty-five centimeters! Its own weight, so imperceptible in water, on land becomes an unbearable burden for the animal. It is not surprising that the elephant seal quickly gets tired from exertion, lies down and immediately falls asleep in a rich, uninterrupted sleep. The elephant seal's sleep is truly sound - in any case, waking it up is not so easy. This is explained by the fact that for a very long time these giants had no enemies on land, and they, like rhinoceroses, had no one to fear and no need to sleep lightly.
The deep sleep of elephant seals repeatedly surprised the English zoologist John Warham, who carried out his observations on Macquarie Island. Every morning, leaving his tent, he came across elephant seals lying sideways in front of the door and blocking his path. These were all molting young males ranging from three to four and a half meters long. They slept completely serenely, their breathing was deep and noisy, sometimes even turning into loud snoring. However, it didn’t take much effort for the researcher to get over them: he walked right on their backs, and by the time these bumpkins realized that they had been walked on in forged boots (which made them raise their heads in fear), the troublemaker was already far away...
No less amazing is the ability of elephant seals to sleep underwater. But how do animals manage to breathe at this time? After all, they have lungs, not gills!.. Scientists managed to figure out the secret of such underwater sleep. After five or ten minutes under water, the animal’s chest expands, but the nostrils remain tightly closed. As a result, the density of the body decreases and it floats up. At the surface of the water, the nostrils open and the animal inhales air for about three minutes. Then it sinks to the bottom again. The eyes remain closed all this time: the elephant is clearly sleeping.
Stones are commonly found in the elephant seal's stomach. Residents of the places where these animals live believe that the stones serve as ballast while the elephants dive under water. There are other explanations. For example, stones in the stomach can contribute to the grinding of food - whole swallowed fish and crustaceans.
Elephant seals feed mainly on fish, and not cuttlefish, as was previously thought. Cuttlefish in their “menu” is no more than two percent. But an adult elephant seal eats a lot of fish. According to the famous zoologist Hagenbeck, the five-meter Goliath elephant seal kept in his menagerie ate an average of fifty kilograms of fish per day! Messages of this kind have led some ichthyologists to argue that the disappearance of elephant seals is a good thing, because they allegedly disputed the fishermen’s catch... However, careful research has shown the absurdity of such conclusions: elephant seals feed mainly on small sharks and rays that are not listed commercial fish... On land, during the breeding season, elephant seals are able to fast for weeks: during this time they do not eat anything, but live off their internal fat reserves.
Careful study of these animals in recent years has lifted the curtain on many of the secrets of their life and behavior. In some ways, these clumsy colossi turned out to be quite a convenient object for the researcher: it didn’t cost anything, for example, to measure their length, calculate the number of individual herds, their composition, age groups, observe the “family” life of these animals, the birth of young animals, etc. d. But try weighing such a huge thing! After all, after all, a male who has reared up (and this is their usual pose of threat) becomes as tall as a good column, and even the sight of just one photograph of such a giant is awe-inspiring. Where can we even think about grabbing him and throwing him on the scales!.. No, studying such animals is not an easy task, and you have to be a real enthusiast to take it on. After all, we must not forget about the climatic features of the places where these observations are carried out: continuous prickly winds, icy water, a bare, inhospitable rocky landscape... And yet, the researchers managed to carry out very important work, which made it possible not only to determine the age of individual individuals, but also to trace their migrations, seasonal changes in the composition of herds, the molting process, relationships in the herd.
But let's start in order. For four years, Australian researchers on Heard and Macquarie Islands systematically branded elephant seal pups, much like domestic calves or foals. By 1961, nearly seven thousand elephant calves had been tagged. This subsequently made it possible to accurately determine the age of a particular animal, the order in which different age groups appear at the rookery, the attachment of individual individuals to their “homeland” or the tendency to change places... Thus, the female number “M-102” for four years in a row gave birth to offspring in the same place and only in the fifth year moved half a kilometer further. Other patterns also emerged. For example, “teenage” groups of elephant seals appear at the rookery much later than adults participating in breeding, which usually occurs from August to mid-November. Shedding in animals of different age groups also occurs at different times. Thus, the rookery is almost never empty - only the contingent of its inhabitants changes.
Among the males, four groups can be clearly distinguished. The first - “teenage” - includes animals aged from one to six years, their size does not exceed three meters. They appear at the rookery in winter, especially after storms, with the obvious purpose of taking a break from swimming. These animals appear before anyone else to molt - in December (the beginning of summer in the southern hemisphere), and then all other animals appear in order of seniority: the older in age, the later.
The second, or “youthful” group is formed by animals aged from six to thirteen years, their size is from three to four and a half meters. They swim to the beach in the fall, soon after the females give birth to their cubs, but they do not engage in fights with older males and swim out to sea even before the start of the rut (after the cubs are weaned).
The next age group is the so-called applicants. Such males, measuring from four and a half to six meters, with a proudly inflating trunk, are in a constantly aggressive mood and try to fight with the owners of the rookery - the owners of the “harems” - powerful old males, trying to take away some of the females from them. These old, experienced males make up the fourth age group.
Such a “harem” owner is a very impressive figure. He is huge, imposing, jealous and aggressive. If he had been different, he would not have held his “post.” After all, a “harem” usually consists of several dozen females, and in order to keep all these curious beauties in obedience, trying to scatter in different directions and “flirtying” with every “contender” that appears, you need remarkable strength and a vigilant eye... Seeing a rival, the owner “ harem" emits an angry roar and rushes towards him, destroying everything that gets in the way: knocking over females and trampling cubs... Such a "master" is generally, as a rule, an extremely "insensitive" animal. It often happens that he crushes newborn cubs to death. A case is described when a male went to bed, crushing a desperately screaming cub under him, but did not even think of getting up to free the unfortunate one.
If the “harem” turns out to be too large for one owner, he is forced to allow “assistants” into his territory, guarding its remote areas...
Observations have shown that the same old and strong male dominates the “harem” throughout the entire breeding season, and younger and weaker males are often forced to give up their place to a rival that is superior in strength. Although male fights usually take place in the water, not far from the shore, panic also begins on the beach at this time - alarmed females scream, the cubs try to escape. Therefore, from “harems” where they are too often disturbed, females try to move to calmer “harems”.
The fight between males is an impressive spectacle. The rivals, having swam up to each other, rear up, rising about four meters above the shallow water, and freeze in this position for several minutes, reminiscent of stone sculptures of monsters. The animals emit a dull roar, their trunks swell menacingly, showering the enemy with a cascade of spray. After such a performance, the weaker enemy usually retreats backwards, continuing to roar threateningly, and, having moved to a safe distance, takes off running. The winner lets out a proud cry and, after making several false throws after the fugitive, calms down and returns to the beach.
When none of the opponents is going to concede, the battle flares up in earnest. Then both powerful bodies loudly hit each other, with a quick and sharp movement of the head, each tries to sink his fangs into the opponent’s neck. However, the skin of the elephant seal is so hard and slippery, and also equipped with a thick cushion of subcutaneous fat, that serious injuries rarely occur. True, scars and scars remain on the neck of males for life, but that’s all.
No matter how terrifying such a battle may look from the outside, in most cases it does not lead to serious bloodshed. Usually everything is limited to mutual intimidation, terrifying roars and sniffles. The biological meaning of this behavior is clear: the strongest is identified, who will take on the functions of a producer during the mating season and, as a continuer of the family, will pass on its positive qualities to the offspring. At the same time, the weaker young male does not die on the battlefield and thus is not excluded from the further process of reproduction of the species...
When individual plots and “harems” have already been distributed, there are practically no battles between male neighbors: if someone violates territorial integrity, it is enough for the “master” to rise up and growl for the border violator to immediately leave.
Tall males do not always show aggressiveness towards humans. And it is not they, but the females that may turn out to be the most dangerous for a researcher who dares to penetrate into the very thick of the herd. John Warham, for example, more than once had to get acquainted with their sharp teeth and run away shamefully, leaving a good piece of his trouser leg as a souvenir for the angry elephant seal...
It is worth telling more about the females. Females are significantly smaller than males - they rarely reach three meters in length and a ton of weight. They grow slowly, but physically develop faster than males: by two to three years they become sexually mature, while males reach sexual maturity much later.
The breeding season lasts from August to mid-November. Females appear at the rookery already “during pregnancy” and within five days they bear offspring. Most babies will be born from late September to mid-October. Owners of “harems” vigilantly guard the females during the period of birth of offspring.
Both females and males arrive at the beach well-fed after fattening up thoroughly at sea. This is necessary for the long “fast” that they have to endure on land: males “fast” for up to two weeks, and females even for a whole month! But during this time, the females will have to endure all the hardships associated with childbirth and feeding the cubs, and the males will have to endure the stress of the subsequent mating season and the associated fights with rivals.
Having appeared on the beach and preparing for childbirth, the females are located at some distance from each other, and do not lie closely side by side, as in normal times. The birth itself lasts only about twenty minutes, and the baby is born sighted. Moreover, he is very handsome: covered with wavy black fur and looks at the world around him with huge radiant eyes. But the “baby” weighs about fifty kilograms, and reaches a length of one and a half meters, that is, the size of an adult seal...
Having been born, the cub emits a short bark, reminiscent of a dog, and the mother responds in kind, sniffs it and thus remembers it. Subsequently, she will unmistakably distinguish him among many other cubs and will be able to return him if he tries to escape.
The upcoming birth can be immediately determined by the fact that loud, large brown birds, called skua in some areas, are circling above the woman in labor. These birds work as “midwives” for elephant seals. With extraordinary agility they remove birth membranes and placenta, and on occasion they can even cope with a stillborn baby. Skua is not averse to treating herself to the milk of nursing females spilled on the ground.
This milk is unusually nutritious (almost half consists of fat), and the cubs grow with unprecedented speed: they gain from five to twelve kilograms per day! In the first eleven days they double their weight, and in two and a half weeks they triple it. They gain length, albeit a little, but they build up an impressive layer of fat - seven and a half centimeters, which they will need first of all: it should protect their body from hypothermia during the upcoming long stay in the water.
After about a month, the females stop feeding the cubs, or “kochoro” as they are called in Patagonia. By this time, their “baby” black fur has been replaced by silver-gray, and they look very well-fed and happy. Soon they leave the “harem”, crawling deeper into the beach, where they rest and build up their muscles. At the age of five weeks, the young begin their first timid attempts at swimming. On quiet, windless evenings, baby elephant seals clumsily descend into the sun-heated water of lagoons or the remaining basins after low tide and carefully swim near the shore. Gradually they become more confident and bolder, they venture on longer sea excursions, until, at nine weeks old, they finally leave their native rookery and swim off into the distance...
And again, one can only be amazed at how intelligently everything is arranged in nature. The young become independent precisely at the period when the prospects for their survival are most favorable. Just at this time, the surface of the sea is covered with a particularly thick layer of plankton, and young elephant seals are provided with easily accessible and high-calorie food for several months.
However, control over marked animals showed something else: half of the cubs die in the first year of their life. Later, losses are significantly reduced, and approximately forty percent of the young animals reach four years of age.
Based on these data, Australian experts came to the following important conclusions. If it is necessary to shoot some part of the elephant seal herd (due to overcrowding of the rookery, lack of food, etc.), then it should be young animals aged from five weeks to one year. But it is completely unacceptable to shoot adult males, as was once practiced in South Georgia, where about six thousand of them were once killed in one summer. Without proper protection of the “harems” by old, experienced males, the herds decline, because young males begin to wage continuous battles with each other, challenging primacy. This is what incompetent human intervention in the affairs of nature leads to and therefore we must avoid rash actions without sufficient scientific justification.
But let's return to the elephant seal rookery, from where the young have just departed. After the “weaning” of the cubs, the females mate again with the owner of the “harem” and soon after that they go to sea - to take a break from the hardships of childbirth, eat well and build up a new layer of fat until their next appearance at the rookery - in February, during the molting period.
And here we should mention one of the most amazing adaptations of the animal body to the conditions of existence: the development of the embryo in the womb of the female is temporarily suspended, and the embryo is, as it were, “preserved” for the entire unfavorable period of the animal’s life - in this case, during molting. (A similar phenomenon is observed in some other animals - many pinnipeds, as well as in sable, rabbit, kangaroo, etc.) The development of the embryo continues only in March, when the molting of females is already completed.
Powerful males, the owners of the beach, show up to molt much later - around the beginning of April. Intense life at the rookery requires longer recuperation.
As already mentioned, the younger ones appear first, and later the older ones. During molting, age groups stay together, but according to gender: females with females, and males with males. Molting lasts, depending on age, one to two months. Until it is completely over, animals will never set sail, because at this time the sensitive blood vessels of the skin are greatly dilated and sudden cooling can cause a disruption in the thermoregulation mechanism, which means inevitable death in icy water.
The molting elephant seal looks most deplorable: its old skin hangs on it in torn rags. First it comes off the muzzle, and then from the rest of the body. At the same time, the poor creatures scratch their sides and stomach with their flippers, trying to speed up this obviously unpleasant process for them...
Shedding animals usually settle down in some moss-covered swamp, not far from the shore, and, restlessly tossing and turning, stir up the loose soil, turning it into a dirty mess. They plunge into it up to their nostrils. The stench around at this time is terrifying. So not every tourist is able to withstand it... By the way, about tourists visiting protected areas. As already mentioned, the Argentine government has declared the small Valdez Peninsula in northern Patagonia a protected area. A colony of elephant seals, numbering several hundred heads, settled on this peninsula. It is called “elephantery” (elephant colony), and recently access has been opened to visitors. One hundred and sixty-five kilometers from the rookery, the resort town of Puerto Madryn arose. And since the water here is often too cold for swimming, many vacationers willingly take excursions to the “elephanteria”. They offer paid tour guides. In addition, the tourist route, which runs through a number of South American countries, includes a visit to the Valdez Peninsula with its elephant seal rookery. The ever-increasing flow of tourists, loudly expressing their delight and constantly clicking cameras, certainly unnerves the animals and disrupts their usual way of life, especially at a time when females give birth. The males who own the “harems” here began to behave much more aggressively than usual. They angrily rush towards annoying visitors, trying to drive them away from “their” territory, or drive their entire “harem” into the water...
There are 2 species in the genus:
southern elephant seal - M. leonina Linnaeus, 1758 (subantarctic waters circumpolar north to 16° S and south to Antarctic pack ice - 78° S; breeds near Punta Norte and Tierra del Fuego in Argentina and on islands of Falkland, South Shetland, South Orkney, South Georgia, South Sandwich, Gough, Marion, Prince Edward, Crozet, Kerguelen, Heard, Macquarie, Auckland, Campbell);
northern elephant seal - M. angustirostris Gill, 1866 (islands off the coast of Mexico and California north to Vancouver and Prince of Wales islands; breeds on San Nicolas, San Miguel, Guadalupe and San Benito islands).
The northern elephant seal was recently close to extinction due to overfishing, but recently, thanks to the ban on fishing, its numbers have increased significantly and continue to increase.
The total number of southern elephant seals is estimated at 600-700 thousand heads, and the northern ones - only 10-15 thousand heads.
Southern elephant seals are hunted on coastal haulouts, and there are restrictions on fishing according to seasons, the size of seals harvested, at least 3.5 m in length, and their number. For example, in 1951 it was allowed to kill 8 thousand elephant seals; harvested 7877. Fat and skin are obtained from hunted animals.
Domain: Eukaryotes
Kingdom: Animals
Type: Chordata
Class: Mammals
Squad: Predatory
Family: Real seals
Genus: Elephant seals
Spreading
Large colonies of the southern elephant seal are located on the following subantarctic archipelagos and islands: South Georgia, Kerguelen, Heard, Macquarie. Outside the mating season, individual individuals can be found on the coasts South Africa, Australia, New Zealand, Patagonia and Antarctica. These animals can cover sea distances of up to 4,800 km.
Northern Elephant Seals used to be found all along the West Coast. North America from Alaska to Baja California. In the 19th century, however, mass extermination of these animals began for the sake of blubber. Every year, thousands of elephant seals became victims of hunters and soon this species began to be considered extinct. Only one small colony of less than a hundred individuals survived on the Mexican island of Guadalupe. After her discovery, northern elephant seals were taken under protection.
In the 1930s, elephant seals came onto land to mate on California's Channel Islands. Northern elephant seals are now found on many islands along the western coast of the continent. In the north, their range reaches the Farallon Islands, and outside the mating season even to Vancouver Island.
The population increases by 15% every year and today this species is no longer seriously threatened. However, the fact that northern elephant seals have gone through a population bottleneck has resulted in extremely low genetic diversity among living individuals, which could become a serious problem under changing environmental conditions.
Description
Elephant seals (Mirounga) are the largest genus in the family of true seals, a class of mammals. There are two species of elephant seals, named according to the hemisphere in which they live.
The oldest confirmed fossils of these animals date back to the Pliocene era and were discovered in New Zealand. Only an adult male has big trunk, similar to the trunk of an elephant. The male uses it to roar during the mating season. Southern elephant seals are slightly larger than northern ones. Sexual dimorphism is pronounced, with males of both species being much larger than females. Average weight an adult male of the southern species can weigh 3000 kg, and its body length can reach 5 m. An adult female weighs about 900 kg, and its body length is approximately 3 m. The color of the animal depends on gender, age and season. It may be rusty, light or dark brown, or gray. The elephant seal has a large body, short front flippers with toes, and webbed rear flippers. Under the skin there is a thick layer of fat that protects the animal in its cold environment. Every year, elephant seals molt. Average duration life span is from 20 to 22 years.
Kinds
There are two types of elephant seals: Southern and Northern. The northern elephant seal reaches large sizes, its body length reaches five meters, weight – up to three and a half tons. Females are much inferior in weight and size to males: weight up to 900 kilograms, body length up to three meters. The color of such elephant seals is gray. They live on the Californian and Mexican islands and on the island of Guadeloupe. Offspring are born in January. Southern elephant seals are brown and slightly smaller than their cousins. They live in the waters of Antarctica, and give birth in October.
Northern elephant seal
Northern elephant seal(Mirounga angustirostris) is a species pinniped mammals from the family of True seals. The size of the male northern elephant seal reaches 6 m, and the female – more than 3 m. The name of this sea animal was given for big sizes and a nose, capable of swelling and then resembling a curled trunk.
Males are very different from females - they are almost twice as large, and during the breeding season they often flare out their noses to appear larger.
This huge pinniped, the northern elephant seal, is found on the Pacific coast of America from Alaska to Hudson Bay.
The northern elephant seal feeds on small sharks, fish, and squid. Elephant seals hatch in December and January so that the females can give birth. The males are the first to come ashore and defend the territory for their harem. Elephant seals form dense colonies on the shore. Elephant seals always have one baby in a litter. It is covered in black fur and remains on the shore for almost five months.
Southern elephant seal
Southern elephant seal (Mirounga leonina) is the most close-up view seals in the world. The trunk of the southern elephant seal is much shorter than that of its northern relative: its length is about 10 cm. This huge, enlarged nose is absent in females and young males. After constant growth trunk reaches full sizes by the eighth year of life and hangs above the mouth with the nostrils down. IN mating season this trunk swells even more due to the increased blood flow. It happens that during fights, more aggressive male loppers tear each other's trunks to shreds. The differences in size between males and females are significant. The male can reach sizes of up to six and a half meters, and the female only three and a half meters. The weight of the male is up to three and a half tons, the female weighs a maximum of 900 kg.
Elephant seals' prey includes fish and cephalopods. Elephant seals are able to dive for prey to depths of up to 1400 m. This is possible thanks to their large mass and a large volume of blood that can store a lot of oxygen. Like whales, the activity of internal organs in elephant seals slows down when diving to depth, which reduces oxygen consumption. The natural enemies of elephant seals are white sharks and killer whales that hunt in the upper layers of water.
Lifestyle
Most Elephant seals spend their lives underwater, feeding on fish and shellfish. They are able to dive to a depth of about 1400 meters, holding their breath for more than two hours. At the same time, the activity of their internal organs slows down, which allows saving required amount oxygen. Their natural enemies are killer whales and white sharks waiting for long-nosed seals in the upper layers of the water.
Elephant seals come ashore only in the warm season in order to give birth to offspring and conceive new ones. For three whole months the huge colonies fill coastal zones. Two to three dozen females give birth to babies under the protection of one male.
Fierce battles are fought for the harems, in which opponents are capable of inflicting serious injuries on each other. Every year, additional scars appear on the body of the strongest and largest males.
It is interesting that outwardly clumsy and clumsy elephant seals literally change before our eyes during fights. Sometimes they even straighten up to their full gigantic height and, vigorously waving their straightened trunk and back bodies perform amazing pirouettes.
Young three- to four-year-old elephant seals are forced to lead a bachelor lifestyle - they are pushed out of the edges of the colony by their more mature eight-year-old brothers. Considering this state of affairs to be unfair, they from time to time try to break through to the “married” females, which leads to new fights.
In the harems their own seething family life. Each “wife” gives birth to one cub, about 80 cm long and weighing 20 kg. His mother feeds him nutritious milk 4-5 weeks, after which he must take care of himself. After leaving it, he remains on the shore for another month, extracting nutrients from the fat layer. During this period, molting occurs, after which the baby goes on its first voyage.
The female is ready for a new fertilization approximately a month after giving birth. Her pregnancy will last a long 11 months. Having conceived, she fattens up a little at sea, and then goes to bed for the post-nuptial molt. Mature males are the last to molt.
Interestingly, during this period, animals of all ages relax so much that you can approach them closely. The body of seals resembles spread jelly, they absolutely do not pay attention to what is happening around them. Having finished their “land” affairs, elephant seals go to the ocean.
Elephant seal feeding
Elephant seals feed on fish and cephalopods, which are caught in the open sea. Latest Research, conducted on the California coast, during which the diving depth of animals was measured, showed that elephant seals are capable of diving to depths of up to 1,000 m. They feed on marine animals, octopuses and even small sharks. Elephant seals have fairly long tusks that protrude from the gums by about four centimeters; The molars are poorly developed, so they prefer prey with a soft body that does not require thorough chewing.
Reproduction and lifespan
Immediately after molting, it is time for love in the life of elephants. From mid-winter to mid-spring, elephants fight, then breed, and raise their future offspring.
It all starts with the elephants crawling onto the shore. The female has been pregnant since last year. After all, this period covers eleven months. Male elephants have nothing to do with raising their offspring.
Having found a quiet, inconspicuous place, the mother gives birth to only one calf. He is born one meter tall and weighs up to forty kilograms. For a whole month, the mother elephant feeds the child only with her milk. Representatives of these individuals have the highest calorie content. Its fat content is fifty percent. The baby gains weight well during feeding. Afterwards, the mother leaves her child forever.
The offspring have formed a sufficient layer of subcutaneous fat so that in the next adaptation, independent month their lives, they could survive. At three months of age, children leave the rookeries and go to open waters.
As soon as the female leaves her child, a period of mating fights without rules begins. The largest and oldest elephants fight to the death for the right to become the sultan of their harem.
Elephants roar loudly at each other, inflate their trunks and wave them, in the hope that this will scare the opponent. Then the powerful ones come into play, sharp teeth. The winner gathers the ladies around him. Some people have harems of three hundred females. And the victim, all wounded, goes to the edge of the rookery. He still finds his soul mate, without the authority of a hyper-male. It’s unfortunate, but during such fights, very often small children suffer and die; they are simply not noticed in battle and are trampled by adults.
Having gathered his women, the leader chooses his passion, menacingly placing his front flipper on her back. This is how he shows superiority over her. And if the lady is not inclined to meet, the male does not care about this circumstance. He climbs all his tons onto her back. Here resistance is already useless.
The sexually mature period begins in the younger generation already at the age of four in males. Females, from the age of two, are ready for mating. Over the course of ten years, female elephant seals can give birth to children. Then they get old. Elephant seals die at fifteen or twenty years of age.
- The amazing ability of elephant seals is to sleep underwater. But how do animals manage to breathe at this time? After all, they have lungs, not gills!.. Scientists managed to figure out the secret of such underwater sleep. After five or ten minutes under water, the animal’s chest expands, but the nostrils remain tightly closed. As a result, the density of the body decreases and it floats up. At the surface of the water, the nostrils open and the animal inhales air for about three minutes. Then it sinks to the bottom again. The eyes remain closed all this time: the elephant is clearly sleeping.
- Stones are commonly found in the elephant seal's stomach. Residents of the places where these animals live believe that the stones serve as ballast while the elephants dive under water. There are other explanations. For example, stones in the stomach can contribute to the grinding of food - whole swallowed fish and crustaceans.
- Among the males, four groups can be clearly distinguished. The first - “teenage” - includes animals aged from one to six years, their size does not exceed three meters. They appear at the rookery in winter, especially after storms, with the obvious purpose of taking a break from swimming. These animals appear before anyone else to molt - in December (the beginning of summer in the southern hemisphere), and then all other animals appear in order of seniority: the older they are, the later. The second, or “youthful” group is formed by animals aged from six to thirteen years, their size is from three to four and a half meters. They swim to the beach in the fall, soon after the females give birth to their cubs, but they do not engage in fights with older males and swim out to sea even before the start of the rut (after the cubs are weaned). The next age group is the so-called applicants. Such males, measuring from four and a half to six meters, with a proudly inflating trunk, are in a constantly aggressive mood and try to fight with the owners of the rookery - the owners of the “harems” - powerful old males, trying to take away some of the females from them. These old, experienced males make up the fourth age group.
- Observations have shown that the same old and strong male dominates the “harem” throughout the entire breeding season, and younger and weaker males are often forced to give up their place to a rival that is superior in strength. Although male fights usually take place in the water, not far from the shore, panic also begins on the beach at this time - alarmed females scream, the cubs try to escape. Therefore, from “harems” where they are too often disturbed, females try to move to calmer “harems”.
- The fight between males is an impressive spectacle. The rivals, having swam up to each other, rear up, rising about four meters above the shallow water, and freeze in this position for several minutes, reminiscent of stone sculptures of monsters. The animals emit a dull roar, their trunks swell menacingly, showering the enemy with a cascade of spray. After such a performance, the weaker enemy usually retreats backwards, continuing to roar threateningly, and, having moved to a safe distance, takes off running. The winner lets out a proud cry and, after making several false throws after the fugitive, calms down and returns to the beach.
- No matter how terrifying such a battle may look from the outside, in most cases it does not lead to serious bloodshed. Usually everything is limited to mutual intimidation, terrifying roars and sniffles. The biological meaning of this behavior is clear: the strongest is identified, who will take on the functions of a producer during the mating season and, as a continuer of the family, will pass on its positive qualities to the offspring. At the same time, the weaker young male does not die on the battlefield and thus is not excluded from the further process of reproduction of the species.
- Tall males do not always show aggressiveness towards humans. And it is not they, but the females that may turn out to be the most dangerous for a researcher who dares to penetrate into the very thick of the herd. John Warham, for example, more than once had to get acquainted with their sharp teeth and run away shamefully, leaving a good piece of his trouser leg as a souvenir to the angry elephant seal.
- Having been born, the cub emits a short bark, reminiscent of a dog, and the mother responds in kind, sniffs it and thus remembers it. Subsequently, she will unmistakably distinguish him among many other cubs and will be able to return him if he tries to escape.
- It is worth mentioning one of the most amazing adaptations of the animal body to the conditions of existence: the development of the embryo in the womb of the female is suspended during molting, and the embryo is, as it were, “preserved” for the entire unfavorable period of the animal’s life. (A similar phenomenon is observed in some other animals - many pinnipeds, as well as in sable, rabbit, kangaroo, etc.) The development of the embryo continues only in March, when the molting of females is already completed.
- The molting elephant seal looks most deplorable: its old skin hangs on it in torn rags. First it comes off the muzzle, and then from the rest of the body. At the same time, the poor creatures scratch their sides and stomach with their flippers, trying to speed up this obviously unpleasant process for them. Shedding animals usually settle down in some moss-covered swamp, not far from the shore, and, restlessly tossing and turning, stir up the loose soil, turning it into a dirty mess. They plunge into it up to their nostrils. The stench around at this time is terrifying.
Video
Including the largest representatives of the order of predatory mammals. They owe their name to the trunk-shaped nose of males and large dimensions. Despite the fact that elephant seals are true seals, in their behavior and some other characteristics they are more reminiscent of eared seals. There are two very similar species - the northern elephant seal, which lives on the west coast of North America, and the southern elephant seal, which lives in Antarctica.
Appearance
Elephant seals did not get their name by chance; they really are animals. gigantic sizes. The body length of male southern elephant seals can reach up to 5 m and weight up to 2.5 tons! Females are much smaller and reach a length of “only” 3 m. Elephant seals differ from other seals in their overall heavy build and large amount of subcutaneous fat. The weight of the fat layer can be 30% of the total weight of the 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 thick, fleshy outgrowth on their nose, similar to a short trunk. During the mating season, the trunk is used for decoration, intimidation and as a resonator, enhancing the menacing roar.
Features of behavior
Elephant seals spend most of their lives underwater, feeding on fish and shellfish. They are able to dive to a depth of about 140 meters, holding their breath for more than two hours. At the same time, the activity of their internal organs slows down, which saves the necessary amount of oxygen. Their natural enemies are white sharks, which wait for long-nosed seals in the upper layers of the water.
Elephant seals come ashore only in the warm season in order to give birth to offspring and conceive new ones. For three whole months, huge colonies fill the coastal zones.
Young three- to four-year-old elephant seals are forced to lead a bachelor lifestyle - they are pushed out of the edges of the colony by their more mature eight-year-old brothers. Considering this state of affairs to be unfair, they from time to time try to break through to the “married” females, which leads to new fights.
Species and habitat
There are two known species of these - northern and southern elephant seals. The former are found on islands along the west coast of North America. They are slightly smaller than their southern relatives. Males weigh 2.7 tons with a body length of almost 5 m. Their trunk reaches 30 cm, which is much larger than that of the “southerners”.
Southern elephant seals gather in colonies on subantarctic archipelagos and islands such as Kerguelen, Macquarie, Heard and South Georgia. Individual individuals are found on the coasts of Australia, New Zealand and Antarctica. The weight of the largest males can reach 3.5 tons, and body length - 6.5 m. Females of both species are half the size of their partners.
Reproduction
Animals begin to arrive at the rookeries at the beginning of spring. This is the end of August - the first ten days of September (in the southern hemisphere, summer begins in December and winter in June). First, pregnant females appear on the rocky shores. The males arrive later. Fights immediately begin between them. Sometimes they turn into whole bloody battles, since elephant seals have quite powerful front fangs.
In the end, everything calms down, and each male finds a harem. It can include 10 females, or a hundred. It all depends on the strength and aggression of the male. The birth of babies occurs in September and October. Females crawl away to give birth in secluded places. The cub is born alone. Its body length reaches up to a meter, and its weight is 25-30 kg.
The mother feeds the baby with milk for a month. Then she returns to the male and becomes pregnant again. The gestation period is 11 months, that is, almost a year. The baby is left alone. He is already getting married without his mother's supervision. When he is 3 months old, he swims away with his peers in open ocean. After molting, at the end of February, adult animals leave the rookery until next spring. Sexual maturity in males occurs at 4 years, in females at 2 years. The female gives birth every year for 10-12 years. These animals live on average 20 years.
Another enemy is man. In past centuries, he mercilessly destroyed harmless animals for their fat. From one killed elephant seal they received at least 500 kg of valuable product. Nowadays, fishing for these is prohibited. In this regard, their number has increased. The number of southern elephant seals today is 750 thousand. At least 250 thousand animals live on the island of South Georgia, and the same number on the Kerguelen Islands. These are the largest rookeries of huge seals, which they share with penguins.
The belonging of elephant seals to true seals today is indisputable, but their position within this taxon is often the subject of debate. King hypothesized in 1983 that elephant seals are most closely related to the monk seal genus and that both genera represent the most ancient forms of true seals. In 1996, Binida-Emodnes and Russell could not find evidence for such a close relationship, but they confirmed the basic position of elephant seals in the taxonomy of true seals.
There are a lot of mammals in nature that we only see on TV. But if you think about it, in fact, we know nothing at all about them. How they live and where. Under what conditions and what do they eat? How they reproduce and raise their offspring. And most importantly, are they not threatened by anything?
Description and features of the elephant seal
Sea Elephant, has absolutely nothing to do with the land elephant. The only similarity between them is that the sea creature, at the end of its muzzle, has a thirty-centimeter thick appendage hanging down, supposedly reminiscent of an elephant’s trunk.
A mammal belonging to the earless seal family. Although some science experts, zoologists, have long refuted this theory. And they claim that their distant ancestor, oddly enough, is the badger and the marten. Elephant seals are huge in size, although they are mammals, they are predators.
They live in the north of the American continent and in the Antarctic region. IN Antarctica elephant seal got caught hiding from poachers. Inhabitants of the subarctic and subantarctic seas.
These representatives, Northern and southern elephant seals, many similar in appearance to each other. Northern elephant seals slightly larger in size than their southern relatives. Their nose, unlike southern elephants, is thinner and longer.
In the seal family, the elephant seal is the largest representative. After all, its size is impressive. Males elephant seal weigh up to four tons in the north, and three tons in the south. They are five or six meters tall.
Their females look like small, fragile inches compared to their men. They don't even weigh a ton. Within eight hundred nine hundred kilograms. Well, and accordingly half as long, only two and a half, three meters.
Males and females also differ in fur color. In males it is mouse-colored. And the females are dressed in darker tones, like earthen ones. Their fur coat itself consists of short, very thick and hard fibers.
But from a distance, it looks very beautiful. Like plush giants crawling out of the depths of the sea. The same cannot be said about the molting period. Half of winter, the animal is on the shore.
His skin covering becomes covered with bubbles, and whole layers peel off from it. During everything maritime elephants They eat nothing, lying in misery on the coastal pebbles. Since the process is quite painful and unpleasant.
The animal loses weight and becomes weak. But having changed my outfit, what does an elephant seal look like, one thing to see. With all our might, already faded, gray elephant seals rush to the sea to restore strength and replenish their bellies.
Male mammals have a big difference from their female counterparts in the presence of a so-called trunk. Photos of elephant seals show that it hangs down at the very edge of the muzzle, covering the mouth.
It all consists of large mounds, as if cobblestones were hidden there. Females do not have it at all. They have cute little faces, like giant plush toys. There are small, hard, highly sensitive antennae on the nose.
Interesting fact about elephant seals is that during the mating season, the male trunk inflates. Blood flows to it, the muscles begin to contract, and from the thirty-centimeter appendage, something half a meter or more appears.
The head of these animals is small in size, smoothly flowing into the body. It has small, dark olive eyes. The skin on the neck of elephant seals is very hard and rough. It protects the animal from being bitten during mating duels.
Their huge body ends in a large, forked fish-like tail. And in front, instead of limbs, there are two fins with large claws.
Lifestyle and habitat of elephant seals
So where do elephant seals live? Northern pinnipeds, permanent residents of Californian and Mexican waters. Even a hundred years ago, they were on the verge of extinction.
The number of their individuals was no more than one hundred animals. They were barbarously killed by stabbing with spears for the sake of valuable animal fat. For elephants, it served as a protective fifteen-centimeter layer, from ice water.
In the same place where they were destroyed, this fat was rendered. Its quantity reached millions of kilograms; that’s how many thousands of individuals needed to be destroyed. To this day, reminiscent of bitter times, vessels covered with algae, bird droppings and rust lie on the banks.
Activists fought hard to save their population. What can't you say about sea cows that have disappeared due to poaching. And already in the fifties of the last century, they multiplied to fifteen thousand individuals.
The southern mammal suffered the same fate; they had to flee, settling on the hard-to-reach islands of South Georgia, Marion. So on Macquar and Heard Islands there are a couple of animal rookeries.
The number of individuals in one rookery amounts to tens of thousands. The Argentine peninsulas have been made protected areas, and for the past fifty years, all hunting of animals has been prohibited.
And already, in the sixties, biologists began studying elephant seals. Despite their huge parameters, these animals feel great in water. They swim beautifully, reaching speeds of twenty kilometers per hour.
And what kind of divers they are. After all, the elephant, the first after whales, will be able to dive for prey to a depth of up to two kilometers. As it dives, its nostrils close.
And this is only known about elephant seals they control their blood circulation. Plunging deeper and deeper, the blood begins to flow only to the heart and brain, without any harm to the animal.
The same cannot be said about spending time on land. In my opinion, this is a whole test for a mammal. Crawling ashore, he struggles to move in the direction he needs. The length of his step is just over thirty centimeters.
Therefore, having coped with its affairs on the shore, the elephant gets tired very quickly. And the first thing that comes to his mind is to urgently get some sleep. Moreover, their sleep is so sound, and their snoring is so loud that scientists have even repeatedly managed, without any fear for their lives, to calculate their breathing rate, listen to their pulse and take a cardiogram of the heart.
They have another unique ability. Incredibly, elephants sleep underwater too. As they dive deep into the water, their nostrils close. And for fifteen to twenty minutes the animal sleeps peacefully.
Then the lungs expand, the body inflates, like balloon, and the pinniped floats to the surface. The nostrils open, the animal breathes for five minutes, then again dives into the depths. This is how he sleeps.
Elephant seal feeding
Since the elephant seal carnivorous mammal. His main diet consists of fish. Also squid, crayfish and crabs. An adult can eat half a hundredweight of fish in a day. To taste, they prefer shark meat and stingray flesh.
Very often, pebbles are found in the stomachs of elephant seals. Some believe that it is needed for ballast when immersing an elephant in water. Others, on the contrary, suggest that the stones contribute to the grinding of whole swallowed crustaceans.
But when the animals begin their mating season, molting, the elephants do not eat anything for months, existing solely on the reserves of fat that they have built up during the fattening period.
Reproduction and lifespan
Immediately after molting, it is time for love in the life of elephants. From mid-winter to mid-spring, elephants fight, then breed, and raise their future offspring.
It all starts with the elephants crawling onto the shore. The female has been pregnant since last year. After all, this period covers eleven months. Male elephants have nothing to do with raising their offspring.
Having found a quiet, inconspicuous place, the mother gives birth to only one calf. He is born one meter tall and weighs up to forty kilograms. For a whole month, the mother elephant feeds the child only with her milk.
Representatives of these individuals have the highest calorie content. Its fat content is fifty percent. The baby gains weight well during feeding. Afterwards, the mother leaves her child forever.
The offspring developed a sufficient layer of subcutaneous fat so that they could survive in the next adaptive, independent month of their lives. At three months of age, children leave the rookeries and go to open waters.
As soon as the female leaves her child, a period of mating fights without rules begins. The largest and oldest elephants fight to the death for the right to become the sultan of their harem.
Elephants roar loudly at each other, inflate their trunks and wave them, in the hope that this will scare the opponent. Then powerful, sharp teeth come into play. The winner gathers the ladies around him. Some people have harems of three hundred females.
And the victim, all wounded, goes to the edge of the rookery. He still finds his soulmate, without the authority of a hyper-male. It’s unfortunate, but during such fights, very often small children suffer and die; they are simply not noticed in battle and are trampled by adults.
Having gathered his women, the leader chooses his passion, menacingly placing his front flipper on her back. This is how he shows superiority over her. And if the lady is not inclined to meet, the male does not care about this circumstance. He climbs all his tons onto her back. Here resistance is already useless.
The sexually mature period begins in the younger generation already at the age of four in males. Females, from the age of two, are ready for mating. Over the course of ten years, female elephant seals can give birth to children. Then they get old. Elephant seals die at fifteen or twenty years of age.
Despite their impressive size, elephant seals also become prey for killer whales. Leopard seal pursues still fragile children. But the most terrible enemies, for many centuries, no matter how scary it sounds, we are people.
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