Animals leading a semi-aquatic lifestyle. River otter (lat. Lutra lutra). Habitat and lifestyle

Mammals have adapted to life in the ground-air, soil and water environments of life, there are flying animals. In various natural climatic zones mammals inhabit forests, meadows, steppes, deserts, mountains. They live along the banks of reservoirs, in rivers, lakes, seas and oceans. According to the way of life, mammals are combined into several ecological groups. Animals of the same ecological group have characteristic features structure, life, behavior (Fig. 218). (For an explanation of the name "ecological group" see § 49, in an essay on the ecological groups of birds.)

Typically land mammals inhabit forests and open spaces. They have a proportionally folded strong body, well-developed high limbs, a muscular neck. They move by walking, running and jumping. The signs of the group are most pronounced in fast-running animals.

Among land animals there are many herbivorous species - these are deer, horses, antelopes, goats, rams, etc. Mammals that feed on branches and leaves of trees have special adaptations. So, the giraffe has a well-developed neck. This allows him to pluck leaves that are inaccessible to other land animals, to see well and to detect enemies in time. Elephants have a powerful compact body, a massive head and a short neck, offset by a long movable trunk.

Predatory animals that lie in wait for prey, for example, a lion, a tiger, a lynx, do not have such long legs like those who run. Relatively long legs in predators chasing prey, such as the wolf and cheetah.

Jumping mammals - hare, jerboa, kangaroo have long strong hind legs and shortened, weaker front legs.

In kangaroos, the weak front legs have lost their support value when landing after a jump. On the other hand, a long tail is developed, on which the animal leans during slow movement, and during large jumps it plays the role of a balancer and a rudder.

Land-arboreal mammals live in forests and are associated with tree-spring-shrub vegetation. They make nests in trees and feed both on the ground and in trees. These animals have an elongated, strong and flexible body, shortened limbs, armed with sharp claws.

Rice. 218. Animals leading different image life: 1 - protein; 2- Noble deer; 3 - bat; 4 - badger; 5 - mole; 6 - wild boar; 7- fur seal; 8 - dolphin

This group includes pine marten, sable, squirrel, chipmunk. Many small terrestrial-arboreal species have a well-developed tail with long spinous hairs, which facilitates gliding jumps. The flying squirrel has a leathery fold on the sides of the body, which improves gliding capabilities.

Soil mammals are adapted to a burrowing lifestyle. Many species spend most of their time underground, rarely appearing on the surface.

The body of shrews is short, valky, the cervical region is invisible, the tail is reduced. The fur is short, dense, without guard hairs, the legs are short with strong muscles and big claws. The auricles are reduced. Vision is poorly developed, and in some underground animals (for example, in a mole rat), the eyes are hidden under the skin. The sense of smell and touch are well developed in shrews. The mole digs the earth with strong, outward-turning spade-shaped forelimbs and pushes the earth to the surface with its head. The mole rat digs the ground with large, protruding incisors.

Flying mammals have fully mastered the air environment - they have adapted to flight. This group includes representatives of the order Chiroptera. Their forelimbs are turned into mobile wings. The flying membrane is stretched between the strongly elongated bones of the hand of the forelimb, the trunk, the hind limb, and even the tail. In fast-flying animals, for example, in the red evening, the wings are long and narrow; in slow-flying ears, they are wide and blunt. In connection with flight, the pectoral muscles are well developed in bats, which, like in birds, are attached to the sternum keel and wing bones. The bats catch insects in the air. Some of them, like birds, make seasonal migrations: fly to warm areas for wintering. All bats have well-developed hearing organs with large auricles that provide echolocation.

Aquatic and semi-aquatic mammals - cetaceans and pinnipeds - are typical aquatic animals. Whales have completely lost contact with land. They have a streamlined fish-like body, the head merges with the body: the cervical region is absent. The caudal fin serves as the organ of movement. The forelimbs, modified into flippers, act as rudders. The hind limbs are reduced. The auricles have disappeared, the external auditory canal is closed, the nasal openings are closed with valves, there is no coat. Well developed subcutaneous fat, providing thermal insulation. In connection with feeding on planktonic organisms, baleen whales lost their teeth and developed a special filtering apparatus, consisting of numerous horny plates, the so-called whalebone.

Pinnipeds spend most of their lives in the water. However, they have not lost touch with the land: they come out onto land, to rookeries, during the breeding season.

Pinnipeds have two pairs of flippers that take part in movement in the water. The coat is reduced, although the cubs are born covered with thick fur. A thick layer of subcutaneous fat plays a thermally insulating role.

Mammals leading a semi-aquatic lifestyle belong to various systematic groups and use different foods. However, they have common features in connection with a semi-aquatic lifestyle: the limbs are equipped with swimming membranes, the tail in the water acts as a rudder, the coat is well developed, there is a thick warm undercoat. Animals leading a semi-aquatic lifestyle carefully take care of the wool: they disassemble, comb, lubricate with the oily secretion of the skin glands. Mammals that lead a semi-aquatic lifestyle include the platypus, muskrat, beaver, otter, muskrat, etc. They swim and dive perfectly in water, move freely on land, although they are noticeably inferior in speed to typical terrestrial animals.

Among terrestrial, soil, aquatic, semi-aquatic and flying animals there are representatives of different orders and families. They have similar adaptive (adaptive) features to similar habitat conditions, constitute separate environmental groups.

Lesson learned exercises

1. List the main ecological groups of animals. Specify the main representatives of each of them.
2. What common features in external structure and behavior possess running and jumping mammals of open spaces?
3. What are the features of adaptations to a tree-climbing lifestyle in animals using several examples.
4. What is characteristic of burrowing animals? Verify with examples.
5. What are the common features of aquatic mammals?

The otter is a semi-aquatic animal and a real thunderstorm of fish. She swims and dives beautifully, which makes it easy to keep up with any large and small fish.

Once this beast inhabited almost the entire Earth where there were fish. The only exceptions were Antarctica, Australia and some islands in the extreme South and North. Otters were common representatives of the river fauna of Europe, Asia, America and North Africa. But people saw them as competitors in catching fish, as well as northern peoples appreciated their waterproof fur. Otters were so mercilessly destroyed that today it is a great success to see the animal in their former habitats. Only in Alaska and Siberia they can be found everywhere.

Places where different types of otters live

The most famous and widespread European otter, or common river otter, inhabits North Africa, Europe (besides Switzerland and the Netherlands) and Asia, not meeting only on the Arabian Peninsula.

In South America, there is a record-breaking otter for length and weight among representatives of the subfamily - giant, or. The length of her body without a tail reaches 150 cm, the tail is 70 cm long, and her body weight is about 30 kg. The main difference between the giant otter and other relatives is its flattened tail. Brazilian otters live in small family groups in quiet rivers: Amazon and Orinoco. They communicate with each other with different sounds. To notify the family of their presence, otters scream sharply and emerge from the water.

Three more species of the otter subfamily inhabit the Central and South America, these are: southern, long-tailed and cat otter. AT North America the Canadian otter lives, which differs from the common otter only large size and the structure of the skull. The Canadian otter can weigh up to 14 kg.

In Africa south of the Sahara, the variegated, white-throated, or spotted otter lives; in Indochina and the Malay Archipelago, the Sumatran otter, in South-East Asia- Indian otter. Also in these parts of the world you can see different types clawless otters.

otter dwelling

Otters spend most of their lives in the water looking for food. But to breed and rest after have a hard day come out on land. Otters live in burrows near the shores of the reservoir in which they live. The otter builds its dwelling in such a way that it can immediately get into the water from it.

There is probably no person who would not know what the Red Book is. The river otter is listed in this book as an endangered animal.

waterfowl predator

The river otter (in Latin - Lutra vulgaris) is a medium-sized mammal that is a predator. The otter comes from the marten family.

Appearance

The body shape of the river otter is streamlined, its length is from 55 to 95 centimeters, excluding the tail, which grows up to 55 centimeters. The animal weighs approximately 6 to 10 kilograms. The tail of the animal is not at all fluffy, but is equipped with large quantity muscles. The eyes are small, round, but located on the face so that the animal sees everything around very well. The animal has a thick neck.

The paws play a very important role for the river otter: they are short and have membranes. The hind legs are longer than the front ones, this feature allows the otter to easily float on the water and swim quickly.

The fur of the animal below is painted in silver or light tone, but on the back and legs it is dark brown. Special structure hairline allows the river otter not to get wet in the water. In spring and summer, the animal molts, but the color does not change.

Habitat

The animal is common in the western part of Europe, in addition, the range of the otter includes Asia. In our country, it lives in almost all regions, even in areas Far North.

The animal lives in rivers flowing in the forest, and even in lakes and ponds. There were times when river otter met on the coast of the sea. The rivers are chosen by those in which there are non-freezing rapids and there is a lot of windbreak on the shore: here it is easier for her to hide and make herself a protected and invisible mink.

The dwelling of the river otter is also interesting: the animal makes the entrance to its hole right under water. The otter lines its burrow with grass. Each burrow has two exits

Lifestyle

The river otter is not always in the water, but the main part of its life is connected with aquatic environment. Scientists have noticed that an otter can hold its breath and stay under water for two minutes. Being on land, it moves sinuously, resembling the movements of a snake. When he goes out on the ice, he almost slides on it

The otter is predominantly a nocturnal animal. During the day, she prefers to sit in her “house”, but with the onset of darkness, she goes hunting. This small animal is distinguished by gluttony and even bloodthirstiness. Otters are also very cunning: when they are pursued, they immediately run into the water. And they can even bite their enemy, moreover, very strongly!

River otters are solitary animals, they do not form colonies, sometimes, however, female individuals lead a joint lifestyle with each other. Otters live up to 10 years.

What does a river otter eat?

Of course, based on the lifestyle, the main food is fish, especially carp, pike and trout. But the otter can also hunt other inhabitants. water world. So, for example, she sometimes catches water rats, crayfish, frogs, shrimps. If she didn’t eat aquatic animals during the hunt, she can look after the “food supplement” on land. Rabbits, birds and other rodents sometimes become its victims. In addition, she can also eat plant foods.

Breeding

The mating season for otters falls on the first months of spring, in some climatic zones this process is year-round. Mating takes place in the water. The female bears offspring for about 63 days, although the entire pregnancy is 270 days. One female is born from 2 to 4 puppies (that's what otter babies are called). At birth, little otters do not see anything at all. Completely cubs mature by two or three years of their life. Already at this age they are able to acquire their own offspring.

A person has met a river otter for a long time. It was very difficult not to notice this animal with the skills of a born swimmer. The otter is of interest not only because of its practical and durable fur. This is a very friendly creature that can be kept in captivity without any problems. With proper upbringing, a river otter can be trained quite easily, as it is a rather peaceful animal that is not inclined to show aggression towards humans.

Characteristic

Because the river otter holds most your life in the water This was reflected in her behavior and habits.

• This animal belongs to the mustelid family, so it demonstrates the skills of a cunning hunter characteristic of its representatives.
• The food for this animal is fish, which it is not difficult for an otter to catch up with.
• While moving on land, the body of the animal looks slightly hunched, but even this allows it to develop a high running speed.
• If a person meets an otter on the ground, then she can still run away from him.
• The best place to build a dwelling are deaf places where people rarely visit. Even though there will be little food in the place of residence, this is more than enough for the otter, since this guarantees the safety of not only him, but also his offspring.
• This animal usually goes hunting in the morning and evening twilight. During strong wind and snowfalls, the otter prefers not to go outside and stays in its shelter for a long time.
• The otter is a very secretive and cautious animal that looks around all the time. It is very difficult to meet an otter in an open area on the shore. She also demonstrates stealth when arranging her house, masking the way out of the water with spruce branches or creating it in those places overgrown with shrubs.
• The river otter is a rather good-natured animal that loves to play. Therefore, if you decide to have it in your home, then you will not be bored.

Appearance

When someone mentions an otter, we usually associate it with something that looks ugly. However, this animal does not correspond to this idea. She is looks pretty attractive, having a very funny muzzle that looks beautiful thanks to long sideburns.

This animal highly valued for its durable and waterproof fur, which is an excellent material for making warm and beautiful fur coats.

Habitat

The otter can be found throughout Western Europe, as well as in Asia. She is also not a rare guest near the southern border of Hindustan and China. The first representatives of this species were found in Greece, Spain, Great Britain and Switzerland, but rather soon their population disappeared, which was the result of active hunting for them. Professionals who understand high risk complete disappearance otters are trying to create suitable housing for them on the lakes and reservoirs of these countries, but so far their attempts have not been particularly successful, and the otter is still on the list of endangered species.

This animal feels most comfortable on rivers with a fast current and a rocky bottom. She is likes narrow rivers about 10-15 m.

Today, the river otter has about 90 thousand individuals, which is very small, given the area of ​​\u200b\u200bour planet.

Key Features

From other members of the family mustelid otter differs in that most of the time spends in the water. Therefore, she chooses for herself such habitats where there is a reservoir. According to experts, it is very important for this animal to have enough food, for which it can walk tens of kilometers on land. She is not inclined long time be in one place. It can only be kept by the presence of a sufficient amount of food.

The otter differs from other animals in that it and stays awake in winter. Therefore, at this time of the year, it can be seen near non-freezing water areas. Thanks to the presence of the polynya, this animal can lead its normal life, breathe and walk on land after a successful hunt.

Nutrition

This animal is not picky about food, so it can eat various types of fish. The main food for otters are:

• carp;
• trout;
• pike;
• small roach;
• carp.

When an otter is on land, it hunts rodents, wading birds and frogs. Also, she will not refuse a large beetle and mollusk.

In search of food, this animal can also look into the fish hole, in which you can find many various kinds fish. An easy prey for the otter are slow-moving flocks, which it easily catches up with and, being in the thick of the maliks, grabs the largest specimens.

Lonely predatory fish can also be of interest to the otter: in order to catch them, the otter sets up an ambush, from where it makes a lightning attack, as a result of which the victim has no chance to escape. She uses a similar tactic for hunting small rodents.

reproduction

Animals accustomed to living alone. Scholars do not have precise information about the periods in which they are usually disputed. Here it is necessary to take into account the climate of their habitat. In the temperate zone, these animals usually mate in March-April. But in Britain, as well as countries with a warm climate, these animals can bear offspring all year round.

Usually the otter starts breeding at the age of 2-3 years. The duration of pregnancy is approximately 8 months, and this does not allow maintaining a high number of representatives of this species. The female can bring at one time no more than two or four cubs. In the first years, offspring require special attention, since it must be protected not only from enemies, but also from the vagaries of the weather.

An otter mother during the period of bearing cubs demonstrates amazing caringness: she is ready to attack anyone if she has any suspicions that someone wants to harm her babies. Because of rapid growth Otters do not stay with their mother for very long. Already upon reaching the age of one year, they leave their mother and begin an independent life.

If you want to adopt an otter, we advise you not to. But if you are determined, you can try. But keep in mind that you must create suitable conditions for this animal: the presence of a deep reservoir with clean water. You must also create conditions for walking the animal along the shore.

Unlike other pets, the otter empties very frequently and loose stools from which comes bad smell. This is due to the fact that she eats fish. This is another reason to think about whether to start an otter at home.

On an industrial scale, these animals are bred in large nurseries, where conditions are created that practically do not differ from natural ones. But even with appropriate care, even experienced breeders are not able to provide everyone with fur products. The thing is that these animals too rarely bring offspring.

They are valued primarily for expensive and rare fur. Many experts note that the fur of this animal is unrivaled in terms of wear resistance. Black fur products have the most spectacular appearance. They have coarse outer hair, but at the same time they have very soft and fluffy. If necessary, designers can create real masterpieces from otter fur: for this they pluck out the outer hair, as a result they get unusual beauty products covered with the most delicate underfur.

Conclusion

The river otter is a very interesting animal that is very difficult to meet, even knowing about its habits. The fact is that she behaves very secretly and never settles near human dwellings. At the first suspicion that she is being watched, she will immediately hide in her shelter. Therefore, it must be monitored very carefully. The river otter may seem like a funny animal to someone, so you may want to have it in the house. However, it is not recommended to do this, as this is a very troublesome business.

In addition to the fact that you have to create conditions for her as close to natural as possible, this animal can cause trouble with its frequent bowel movements which will give off an unpleasant odour. Therefore, if you have not yet lost the desire to keep a river otter at home, be prepared to put up with this shortcoming.

It is so different from its relatives that zoologists are ready to recognize it as a separate detachment. The river otter, which is very difficult to photograph due to its caution, lives along the banks of fresh water bodies. She prefers mountain rivers or those whose rapid current does not allow water to freeze in winter, as well as with a rocky or pebble bottom. Therefore, in the valley large waterways it is rare to find her.

It is known that for plants there is a special list - the Red Book. The river otter, unfortunately, is also introduced there, and not because it has become a victim of uncontrolled hunting. The fact is that this small predator can only live in very clean water, and the industrial rise in Western Europe in late XIX the century was very polluted The otter completely disappeared from the expanses of Switzerland, Great Britain, Spain, Sweden and the Netherlands (now there are attempts to introduce animals in their usual habitats). And in other parts of the Old World, the number of animals has decreased significantly.

Subspecies of these creatures are found in North and Latin America, in Asia (up to South China) and, of course, the river otter does not live in arctic tundra. After all, even in winter, she needs open water. The largest of the species is the South American giant otter, which can weigh up to 25 kg. By the way, these giants, unlike their counterparts, who prefer to live alone, settle in small communities.

great swimmer. Everything in her physique is adapted for a long stay under water. The body is streamlined, elongated, the hind legs are longer than the front ones, there are membranes between the fingers. Almost imperceptible ears are equipped with a special valve that prevents water from entering the auditory shell. Since the animal does not have a thick layer of fat (and remains flexible and fast), all hope for the preservation of heat relies on fur. It is dense, with coarse guard hairs and a delicate wavy undercoat. But most importantly, it does not get wet at all! When moving in water, the otter is helped by a flat head and a long, muscular tail. The color of the otter is dark brown on top, and its belly is light, slightly silvery.

Eurasian river otter - small predator. Males reach a body length of 90 cm and a weight of 10 kg, females are much smaller (55 cm and 6 kg). Their main food is small fish, but these hunters do not disdain eggs and chicks of river birds, frogs, caddisflies. The habitat of one individual is rather small - 250 m of the coastal strip, which it marks with excrement. But the otter neighbors live peacefully, and in times of famine converge to places where there is food. The animal digs one permanent hole, the entrance to which opens under water. The lair itself is dry, warm, lined with moss, grass and leaves. In winter, animals stay close to polynyas or gullies.

The river otter prefers to hunt in the morning and in the evening. During the day, she basks in the sun, perched on a stone or a trunk of a fallen tree. Her disposition is cheerful and mischievous. Otters often play with themselves: uttering squeals and chirping, they love to roll into the water from inclined surfaces. In captivity, they are quickly tamed, recognize the owner and fawn like cats. In the wild, they live up to 10 years. Otters are very caring mothers. The female bravely defends her brood (usually there are 3 or 4 cubs) even from humans. The young live with the parent for about a year.