home » For full » Why is the seal called curious. Nerpa - Baikal mammal

Why is the seal called curious. Nerpa - Baikal mammal

On May 25, a regional children's and youth ecological holiday is celebrated - the day of the seal. It was first held in 2003 in Irkutsk.

The holiday very quickly became popular in many regions of Russia, including the Irkutsk region, the Republic of Buryatia and other regions of Siberia, and is included in the calendar of ecological dates. We have collected 10 unique facts about this rare mammal.

The Baikal seal is one of three species of freshwater seal found nowhere else but this lake. The main seal rookery is located on the Ushkany Islands, where you can find a lot of food and there are practically no people who pose the main threat to these animals.

Why is the Baikal seal interesting and unique?

1. The seal is the only mammal of Lake Baikal. According to morphological and biological features, the Baikal seal is close to the ringed seal that lives in the seas of the Far North and the Far East. There are also some signs of similarity between the seal and the Caspian seal.

2. It is not known how the seal ended up in Baikal. Some researchers believe that it penetrated into it during the ice age from the Arctic Ocean through the Yenisei-Angara river system simultaneously with the Baikal omul. Others believe that the entire family of true seals (Caspian, Baikal and ringed seals) originally appeared in large freshwater reservoirs of Eurasia and only then settled in the Caspian Sea, the Arctic Ocean and Baikal. However, this mystery has not yet been solved.

3. The Baikal seal can accelerate under water up to a speed of 25 kilometers per hour. She is a consummate swimmer and can easily avoid danger at this speed.

4. The seal dives to a depth of 200 meters and remains under water for 20-25 minutes.

5. The seal can suspend pregnancy: no other animal on Earth can do this. In some cases, the embryo stops developing, but does not die and is not destroyed, but simply falls into suspended animation, which lasts until the next mating season. And then the seal gives birth to two cubs at once.

6. Pregnancy of seals lasts 11 months. Females puppies in March-April. Fur seals are white, so they are called pups. This coloration allows them to remain almost invisible in the snow in the first weeks of life. With the transition to self-feeding by fish, the cubs molt, the fur gradually acquires a silver-gray color in two or three months old, and in older and adult individuals it becomes brown-brown.

7. The fat content of Baikal seal milk is 60%. The nutritional properties of milk help seals gain weight quickly.

8. Seals build their winter homes from under the ice. They swim up to a suitable place, make holes - vents, scraping the ice with the claws of their forelimbs. As a result, their house from the surface is covered with a protective snow cap.

9. The Baikal seal is a very cautious, but inquisitive and intelligent animal. If she sees that there is not enough space on the rookery, then she begins to rhythmically spank with flippers on the water, imitating the splash of oars, in order to frighten her relatives and settle in the vacant place.

10. Seals live 55-56 years. Adult animals reach 1.6-1.7 meters in length and 150 kilograms of weight. Sexual maturity occurs in the fourth or sixth year of life. Females are able to bear fruit up to 40-45 years.

From whom should the Baikal seal be protected?

Huge losses of the Baikal seal were recorded in 1996, mainly due to licensed and poaching hunting, as well as chemical pollution of the lake.

“Today, the approximate number of Baikal seals is from 75 to 100 thousand heads. This is quite a lot, but fishing is not being carried out now,” said Mikhail Kreindlin, Greenpeace expert on specially protected natural areas.

Formally, the Baikal seal is still a commercial species and is not listed in the Red Book, but hunting for it was banned in 1980. Until 2009, a quota was issued for industrial capture of 50 animals. Since the end of 2014, the quota has been issued only to research institutes.

“Currently, a drop in the number of seals is not recorded, but the state of Baikal cannot but affect its inhabitants. For example, the recent drop in the water level has led to the drying of spawning grounds for fish, the main food for seals. There are also threats that have not yet been realized, for example, the construction of the Shuren hydroelectric power station on the Selenga River, the largest tributary of the lake, which can also lead to severe shallowing and indirectly threaten the seal too," said Mikhail Kreindlin.

Seals are a genus from the seal family. Sometimes seals are included in the genus of common seals. There are 3 species in the genus seals.

The ringed seal is found in the temperate and cold waters of the Pacific and Atlantic oceans and in the Arctic Ocean; in Russia it lives in all northern seas, and also in the Bering and Okhotsk seas. The Caspian seal, or the Caspian seal, lives in the Caspian Sea. The Baikal seal, or the Baikal seal, inhabits Lake Baikal.

The uniqueness of the Baikal seal lies in the fact that it is the only mammal that lives on Lake Baikal. Belongs to the seal family. A rather large mammal, the body length reaches up to 140 cm, and the weight reaches a full 90 kg. Males are always larger and heavier than females. Even a newborn cub is particularly weighty; at birth, it weighs about 3 kilograms.

Appearance and behavior

The color is rather monotonous light gray on the back, closer to the belly, the transition to yellow begins. Such, dull at first glance, coloring perfectly masks the seal. In nature, she has no natural enemies, the only one who hunts her is a man.

The skin of the seal is considered the warmest and most practical, so the fishermen catch this animal. The indigenous inhabitants of Transbaikalia are happy to use the meat of the hunted seal for food.

The seal has very powerful paws crowned with strong nails, which allows it to tear apart a thin part of the ice in winter in order to breathe oxygen. The constant presence under water at dusk has formed a certain device of the eyes, they are rather convex, which allows the seal to easily get food for itself. The seal can stay under water for up to an hour, holding its breath for this period, it is an amazing swimmer, thanks to the increased concentration of hemoglobin, it can dive up to 300 meters deep.

Its natural habitat is water depths, despite its impressive dimensions, it is very maneuverable and dexterous in water, under water it can reach speeds of up to 25 km / h. But, like all seals, it is completely clumsy on land, in moments of danger, being on the shore, it can go to the races, which looks pretty funny.

Food

The favorite food of the seal is the small and large golomyanka, long-winged goby, yellow-winged goby, sandy sculpin. Golomyankas occupy the main stage in the nutrition of seals. The seal eats from 3 to 5 kg of fish per day. And it takes 2-3 hours to digest food in the stomach.

reproduction

Females after 4 years of life are ready for mating and reproduction, but males are a little behind and mature a couple of years later. The mating season for seals lasts from late March to late April. At this time, the males make every effort to invite the female to the ice to mate. And if successful, a small seal will be born in 11 months. A natural feature is to delay pregnancy for 2-3 months, that is, a fertilized egg may be in the fading stage, and only after this period, the female's pregnancy will begin to develop.

It is the female who takes care of the place of the future birth for her cubs, usually this is a den in the snow, since the cubs appear in winter. After the birth of the baby, the seal mother will feed him with milk for 3 months. Baby seals are born completely dependent on their mother, their skin is painted white. During the feeding period, the mother will only go fishing for her own food, the female spends the rest of the time with the babies. When she is in the lair, the temperature there rises to +5, although outside it the temperature can drop to -15.

The ringed seal is so named for the light rings with a dark frame that make up the pattern of its coat. Adults reach a size of 135 cm and a weight of 70 kg.

Dimensions and appearance

The ringed seal is one of the smallest. The body length of an adult seal is up to 150 cm, the total weight usually does not exceed 50-60 kg. The body is relatively short and thick. The neck is short, the head is small, the muzzle is shortened. Vibrissae are flattened with wavy edges. The hairline of adult animals, as in other species, is short, hard, with a predominance of awns.

Adult coloration varies widely. Characterized by the presence of a large number of light rings scattered throughout the body. The general background of the coloration of the dorsal side of the body is dark, sometimes almost black, the ventral side is light, yellowish. There are no light rings on the flippers. Males and females are colored the same.

Habitat

The ringed seal is an inhabitant of the Arctic and subarctic waters of the Atlantic and Pacific Oceans, where it is found everywhere. It lives mainly in coastal shallow water areas. It also inhabits the Baltic Sea, lakes Ladoga and Saimaa.

In Russia, the seal is distributed from the Murmansk coast to the Bering Strait, including the White Sea, the waters of Novaya Zemlya, Franz Josef Land, Severnaya Zemlya, and the New Siberian Islands. In the Far East, the ringed seal is called Akiba. In the Bering Sea, it lives along the western (where it descends to the south almost to Cape Lopatka in Kamchatka) and eastern (up to Bristol Bay) coasts, including the waters of the Commander and Aleutian Islands. In the Sea of Okhotsk, it inhabits the entire coastal part, including numerous bays, as well as the coast of Eastern Sakhalin, the Sakhalin Bay and the Tatar Strait. Reaches the shores of the island of Hokkaido.

Outside our waters, the ringed seal lives off the coast of Northern Norway, Svalbard, the eastern (up to 75 degrees N) and western coasts of Greenland, in the northern part of the Gulf of St. Lawrence and near the island of Newfoundland. Inhabits almost the entire Canadian Arctic Archipelago, including Hudson Bay.

Migration in ringed seals is weakly expressed. Obviously, she comes the farthest to the north. She spends most of the year in ice-covered bays and fiords. In autumn, as the water freezes, the animal does not migrate south, but makes holes in the ice, to which it regularly swims up to breathe and rest. Usually, the seal spends 8-9 minutes under water, but if necessary, it may not rise to the surface for up to 20 minutes. It takes 45 seconds for a seal to stock up on a new portion of air.

reproduction

In the Sea of Okhotsk and Chukchi, in the White and Barents Seas, females give birth from mid-March to mid-April, in the Baltic Sea and Lake Ladoga - mainly in early March.

The cubs are born in a long, thick white coat, which is replaced, apparently, after 2 weeks. The length of the newborn is about 60 cm, weight up to 4 kg. Milk feeding lasts about one month. During this time, the body length of the cubs increases by approximately 10 cm, and the weight doubles. Then the growth rate slows down. By winter, the body weight of young seals reaches 12 kg, and its length is 80 cm or more. One-year-old seals have a body length of up to 84 cm, weight up to 14 kg.

The ringed seal is the only one of all seals that builds a nest for its young. In March or April, when the ice begins to break, the female makes a hole in a snowdrift with a tunnel leading to the water.

Females give birth to one baby pup. A characteristic distinguishing feature of this species is that in many cases the cubs that have lost their mother do not die, but survive, but their growth is greatly slowed down, and as a result they remain dwarfs.

Female ringed seals reach sexual maturity in most cases at the age of 5-6 years, and the first offspring are brought at the age of 6-7 years. Males start breeding mainly at the age of 6-7 years. In ringed seals, growth stops at the age of 10 years.

The food of the ringed seal is based on two groups of animals - fish and crustaceans, and only those that form large accumulations in the upper layers of the water.

Appearance

The body length of the Caspian seal is up to 150 cm, and its average weight is 70 kg. The body is relatively thick with a short length. The neck is not long, but noticeable, the head is small. The edges of the flattened vibrissae are wavy.

The color of this seal in animals of different ages and different sexes is different. There is a large individual variation in coloration. Basically, the upper surface of the body has a darkish background, the ventral surface is light gray. On the sides, the transition of tones is gradual. Dark gray, brownish, sometimes almost black spots of various sizes and shapes are randomly scattered throughout the body. Spotting is more pronounced on the back than on the belly. Males are more brightly and contrastingly colored than females.

Habitat

The Caspian seal lives only in the Caspian Sea, where it is found everywhere from the Northern Caspian to the coast of Iran. The northern half of the sea is generally more populated than the southern.

The Caspian seal makes regular seasonal, although not long, migrations. During the winter months, almost the entire population is concentrated in the ice zone of the Northern Caspian. As the ice disappears, the animals move to the south and by the beginning of summer they are widely distributed over the waters of the Middle and South Caspian. Here they feed heavily, and in early autumn they begin to move again to the Northern Caspian.

Food

The basis of the diet of the Caspian seal is made up of various types of gobies. The second place in nutrition is occupied by sprat. In even smaller quantities, these seals eat atherina, shrimps, and amphipods. Of the valuable commercial fish, herring is sometimes found in their stomachs, which they eat in certain periods of the year in small quantities. The composition of food during the year changes little.

reproduction

The period of puppies in the Caspian seal is shorter than in other species - from the middle of the last decade of January to the end of the first decade of February. The majority of females bring offspring during this period. Mating begins after the puppy and lasts from mid-February to early March. Reproduction and mating take place on the ice of the Northern Caspian.

The female brings, as a rule, one large cub up to 75 cm long, weighing 3-4 kg. It is covered with long silky almost white hair. The duration of milk feeding is about 1 month, and during this period the length of the cub increases to 85-90 cm, and body weight - more than 4 times.

During the second and third decades of February, even during the lactation period, the cubs molt, replacing the children's white hairline. Shedding cubs are called sheepskin coats, and young animals that have completely replaced children's hair are called sivaris. The short hairline of the sivar has an almost monochromatic dark gray color on the back and a light gray (whitish) monochromatic color on the belly. As the animal grows, with each annual molt, the spotting of color appears brighter and brighter.

Females reach sexual maturity, apparently, at the age of 5, so that most of the females bear the first offspring at the age of 6 years. After that, most sexually mature females breed annually.

The seals do not form large and dense accumulations on the ice. Females with cubs are usually located at some distance from one another. Preferably, they cub on strong ice floes, in which they make holes (holes) even at a time when the ice is thin. These holes do not freeze due to the constant use of their animals to go out onto the ice. Sometimes seals are forced to widen their eyes with the help of sharp claws on their front flippers.

During the molting after the breeding and mating period, when the ice area is reduced, the Caspian seals form relatively dense aggregations. Animals that did not have time to molt on the ice sometimes (in April) lie down in groups on shalygs (sand islands) in the northern part of the Caspian.

In the summer months, Caspian seals stay in open water separately in a large area of the Middle and South Caspian, and in autumn (September-October) they gather in the northeastern part of the sea, where they lie in dense groups (males and females of different ages) on shalygas.

In principle, it is impossible to somehow compare these animals, since seals are a collective concept, which includes not only seals, but also monk seals, elephant seals, Ross seals, crabeater seals, leopard seals, Weddell seals, sea hares (also called bearded seals), hooded seals, long-snouted seals, harp seals and striped seals. Well, seals are one of the genera of this diverse family, or the so-called subfamily.

But if we compare seals with all other animals of the family, the former are considered smaller. So, the average size of a ringed seal is only about 1.25-1.3 m, and its weight is about 90 kg. Elephant seals are considered the largest animals of this family - the weight of males of these animals can reach 3.5-3.7 tons, and the length from the tip of the nose to the end of the tail is 6.5-6.7 m.

Different for all genera of seals and habitats, eating habits, as well as the timing of growth, raising cubs, the timing of weaning from the mother, and many other aspects.

More about seals

In addition to the already mentioned ringed seal, which is also called akiba, or Pusa hispida in Latin, this genus of animals includes the Baikal seal, or Pusa sibirica, and the Caspian seal - Pusa caspica. Unfortunately, all of them were and are objects of fishing, as a result of which some subspecies have already been included in the Red Book of Russia and the world.

The Baikal seal, as its name implies, lives only in the fresh waters of Lake Baikal and is its endemic. The beds of these animals are usually located on the shores of the Ushkany Islands of the lake, and very often these curious seals swim up to the ships and to the shores of the lake. Animals feed on lake golomyanka and Baikal goby, and in a year one individual is able to eat up to 1 ton of food.

In turn, the more heat-loving Caspian seal is an endemic of the Caspian Sea. Moreover, these animals can often be seen at the mouth of the Volga River, as well as not far from the city of Volgograd. This seal lives up to 50 years, and can catch food at a depth of up to 80 m. Basically, these are sprat and various crustaceans.

The ringed seal is found only in the waters of the Arctic - in the Arctic Ocean. Unlike all other seals, they live exclusively alone and do not form massive haulouts. These animals are traditionally hunted and slaughtered by the Eskimos. By the way, it is the ringed seal that is depicted on the coat of arms of the city of Snezhnogorsk.

The Baikal seal is one of three species of freshwater seals that live on our planet. This animal is endemic and the only mammal living in the waters of Lake Baikal, located in the south of Eastern Siberia. It is considered one of the most interesting objects of the so-called ecological tourism, which is rapidly gaining popularity. Read more about the lifestyle and habitat of the Baikal seal later in this article.

Short description

Adult animals can reach a length of 165 cm, and their weight varies between 50-120 kg. The growth of seals stops only at the nineteenth year of life, however, at the same time, body weight can periodically gain or decrease. The Baikal seal lives on average 55-60 years.

Under water, the animal usually swims at a speed of no more than 8 km / h, but during hunting or in case of a threat, it can increase significantly. Getting ashore, the seal slowly moves with the help of flippers and tail, however, sensing danger, it gallops rather dashingly, pushing them off the ground.

Baikal seals do not need to dive too deep. The fact is that they feed on such non-commercial fish as golomyanka, omul and goby, which are found in the illuminated areas of the lake. But, despite this, they are able to dive to a depth of 200-300 m and withstand a pressure of 21 atmospheres. The seal can be under water for more than one hour. This time is quite enough to find food or escape from persecution.

The first mention of the animal

It belongs to the beginning of the 17th century. At that time, the second Kamchatka, or, as it was also called, the Great Northern Expedition, organized by Vitus Bering himself, passed here. It also included a group of researchers headed by I. G. Gmelin. It was she who was engaged in a more in-depth study of the nature of Lake Baikal and its environs. It was then that a seal was first seen, which was later called a seal.

Then the locals claimed that the same animal was found not only in the waters of Lake Baikal, but also in the Baunt lakes. It is assumed that the seal could get there in two ways - through the Lena or Vitim rivers. Some researchers are inclined to the version that the seal could have penetrated there directly through Baikal, since it had previously communicated with these lakes. However, none of the above assumptions has yet been able to find reliable confirmation.

Favorite habitats

The Baikal seal can be found throughout the reservoir, but the largest concentration of these animals is most often observed in the middle and northern parts of the lake. However, their most favorite habitat is the Ushkany Islands, which are part of the National Park called Zabaikalsky.

If there is no ice on the lake, the seals prefer to rest, lying on the rocks protruding from the water and basking in the sun, alternately exposing one or the other side to its warm rays. The largest number of these animals can be observed in June, when they come to the surface for a long time and are located along the rocky shores of the Ushkany Islands.

Where does the Baikal seal winter?

In the cold season, animals live on the ice in special lairs located under the snow. Often they are found in hummocky areas of the lake. When Baikal begins to freeze, animals make the main ice on the ice, the average diameter of which is about 150 cm. It is interesting that seals can keep it in this state for a long time, from time to time removing the ice formed on it.

With the onset of severe frosts, when the lake freezes, these animals, being under a layer of snow, breathe only through secondary vents. To do this, they rake the ice with the help of their forelimbs, which end in strong claws. Thus, a seal's lair can have up to a dozen such vents located along its perimeter. The diameter of the secondary vents is no more than 15 cm. Such a hole is quite enough for the animal to stick its nose in there.

reproduction

Puberty in these animals occurs already in the fourth year of life in females and in the sixth in males. The period of bearing cubs of Baikal seals lasts 11 months. After the female is 40 years old, she is no longer able to give birth. In her entire life, she can give birth to 20, and under favorable conditions, more cubs.

Before giving birth, the female prepares a reliable snow shelter. Usually one or two cubs are born. The weight of newborns is no more than 4 kg. Seals have soft white fur, which is why they are often called pups.

Caring for offspring

The snow lair is quite warm: at an external temperature of -20 ⁰C inside the “room”, it is +5 ⁰C. Baby seals stay in the shelter for five weeks. During this time, they eat only mother's milk and do not leave it for a minute. Before the lair begins to collapse, the squirrel manages to molt. The female leaves her cub only to hunt.

The lactation period for seals is about 60-75 days. It can last much longer, as it directly depends on the presence of ice cover. Before the babies begin to hunt on their own, they completely molt. At the same time, their fur turns from white to gray-silver. Color change occurs gradually and lasts about three months. In adult seals, the fur has a brownish-brown color.

The Baikal seal, starting from birth, knows how to build vents. This fact was confirmed by a specially conducted experiment. To do this, a small sheet of foam plastic 5 cm thick was placed directly on the water in the aquarium, while the rest of the space was left free. Several small seals, whose age did not exceed two months, began to make blowholes in the floating platform - special holes through which they breathed, sticking their nose in there. Surprisingly, the cubs did this, despite the fact that there was open water next to them. However, they, as if not noticing this, swam up from below, inhaled the air and again descended to the depth.

To conduct this experiment, several Baikal seal cubs were caught, which were no more than two weeks old. At this age, they still feed on their mother's milk, which means that the animals have never been immersed in water in their lives. When they grew up a little, during the first voyage, the seals demonstrated that the ability to make vents in the ice is their innate ability.

Another interesting fact is that this animal is able to sleep for quite a long time right in the water, while practically not moving. Sleep can continue until the oxygen in the blood runs out. It is so strong that scuba divers can swim close to the Baikal seal and even turn it over, and the animal continues to sleep peacefully. Such fearlessness of seals is due to the fact that they have no natural enemies in this ecological environment. For them, only human activity poses a real threat.

Animal fishing

The Baikal seal, whose photo is located in this article, is an object of hunting. Its meat, fat and fur are especially valued, from which hats are sewn. In addition, hunters often use the skin to pad their skis. Seal meat can be eaten. They also eat boiled flippers, which are considered a delicacy. The most tender and tasty is the meat of young individuals.

In ancient times, seal fat was used in soap making and leather production. In 1895-1897, animal fat was used in large quantities to illuminate the mines that are part of the Lena gold mines. As for the locals, they were sure that seal fat was healing, so they used it for stomach ulcers, as well as for various lung diseases.

The hunting season for the Baikal seal begins in April and lasts as long as it is possible to move around the frozen lake. In addition, the animal can be caught with the help of nets. This method is more rational, since there are no losses that occur during shooting. The fact is that wounded animals often go under the ice. Where they die. Nowadays, seal hunting is not prohibited. Every year, at least 5-6 thousand seals are caught or shot.

Cause of mass death

It first happened in 1987. Recently, some scientists have been carefully studying the causes of the mass death of animals. Their diagnostics showed that the seals died due to the carnivore distemper virus. Interestingly, this disease affects both domestic and wild animals.

There is documented evidence that about one and a half thousand individuals died from distemper in 1987 and 1988. At the same time, fishing during the 80s of the last century amounted to at least 5 thousand heads. Fortunately, the Baikal seal was not included in the Red Book, as it was noticed that the population of the animal exceeded the optimal number. In addition, such shooting, according to scientists, is even useful, as it helps to reduce intraspecific competition and allows animals to gain weight faster.

Seal habitats

Since the ringed seal belongs to the pagethode (associated with ice) seals, it lives, as a rule, in those water bodies that are covered with ice at least for the winter. For reproduction, it knocks out mainly coastal immovable ice. Apparently, only Okhotsk seals deviate from this rule, and in some places, probably, Chukchi seals. Due to strong tidal currents in the Sea of Okhotsk, stable fast ice usually does not form, and akibs are forced to use for breeding and for molting broken moving ice drifting relatively close to the coast.

At the same time, they whelp mainly at some distance from the edge facing the coast, choosing rather strong, somewhat hummocked ice floes. A place for puppies is any more or less solid ice floe with holes made in the neighborhood. In most cases, the cub lies openly, not under the snow cover. In all other areas, during the breeding season, seals keep in a strip of fast, coastal ice, hidden from prying eyes by snow cover. The calf is born in snow caves on ice near a hole or in voids formed among heaps of ice fragments during hummocking. Young animals that do not participate in reproduction (and, apparently, partly also adult males) stay outside the fixed fast ice in the areas of broken and drifting ice closest to it.

Arctic seals, and much later, during the molting period, remain mainly on the same coastal immovable ice, strongly decayed from time and heat, located near holes (holes). Young animals also crawl out there, except for the offspring of the current year, which, after the end of lactation and the change of the embryonic hairline, leaves the fast ice.

Especially at this time, the seals lay down on the ice, which persists for a long time near the heavily indented coasts, in the straits between the islands. Such, for example, are the southern coasts of Novaya Zemlya, the coastline in the Bering Strait, and many other parts of the range. Nevertheless, seals do not avoid shallow water areas with a more or less even coastline, such as, in particular, the Yamal shallow water or the northern coastal strip of the Chukotka Peninsula. Naturally, in such conditions, the seal settles at a greater distance from the coast, outside of continuous ice heaps. In the Sea of Okhotsk, during the molting period, seals again lie down on separate small, preferably scattered ice floes. At this time, seals are completely illegible in choosing a place and can lie down on a clean and dirty ice floe, on a hummocky and smooth one; sometimes they can be found even on the top of the hummock.

Views