Why do birds fly away? What warm lands do birds fly to? Seasonal migrations of birds. Reasons for migration

According to statistical data, on the territory of Russia there are more than 60 species of birds flying away for wintering in warmer climes... Seasonal migrations are the prerogative of all migratory birds, without exception. Resettlements are made both long and fairly short distances. To understand which species of birds are migratory, it is necessary to understand that their migrations depend on what they, in fact, are. Most of all in nature are insectivorous birds. They are balanced by carnivorous and granivorous birds.

With the onset of cold weather, all insects, which many birds enjoy with pleasure, disappear. In this regard, birds have to fly to where there is never snow, where the abundance of tasty insects does not end all year round... Such migratory birds include robins, finches, and, of course, "spring messengers" - swallows.

Swallows feed on rather large insects, including dragonflies and May beetles. They catch them on the fly. They hibernate on the Mediterranean coast. It is curious that some of them even fly to hot Africa. Therefore, it is simply impossible to meet swallows in Russia.

In winter, rivers and lakes freeze, which poses a great threat, for example, to carnivorous herons that feed on frogs and fish. They also have to leave their native lands. The "vegetarians" who eat grasses and seeds also suffer, since in winter all this is covered with a white sheet of snow. The thermophilic cranes are one of the most famous herbivorous migratory birds.

If you closely observe the cranes, you will notice that already in September they are preparing to leave. At this relatively early time for resettlement, they are already gathering in flocks. Cranes leave their native land until spring, saying goodbye to people with their beautiful guttural cry. For complete objectivity, it should be noted that not all types of cranes fly away. This is done only by those who are forced to nest and breed in the northern regions of Russia.

Who stays for the winter?

Only those birds that have managed to “find mutual language" with a person. They are called sedentary. The most famous of them are,. The fact is that they have adapted to feed on waste found in landfills and in garbage cans. In addition, a person feeds them, resorting to the help of special feeders.

Bird's "compass"

Scientists have proven that migratory birds are perfectly oriented in the geography of their migrations. They can sense not only latitude, but also longitude, guided by the sun and stars. This is one of the versions of this bird phenomenon.

According to another version, migratory birds return to their permanent nesting sites, focusing on the Earth's magnetic field. In the journal Nature, a corresponding was published on this topic. In addition, it has been documented by ornithological scientists who ring migratory birds and then observe them in the same places for several years in a row.

However, despite this, there is still no consensus among ornithologists and researchers about the work of the so-called bird's "compass".

Twice a year, residents of northern latitudes witness such a natural phenomenon as the arrival and departure of migratory birds. At the beginning of the year, this event is a symbol of the onset of spring, and in the fall - the approach of cold and frosty weather. In fact, an unambiguous answer to the question of why annually birds fly south, not even the birdwatchers. There are several versions explaining the reasons for this phenomenon.

Instructions

For example, O. Bondarenko, a scientist working in natural science and non-academic, associates the constant migration of birds with the earth's magnetic field. He explains this by the fact that biological processes occur in the body of birds at an increased speed. This is what ensures their high muscle mass and lets them. Those processes that occur annually - incubation and feeding of chicks, loss of fat mass and a change in the balance between fat and muscle, make them fly, where the influence magnetic field land is less noticeable. Having gained weight, they begin to feel discomfort in the low magnetic field and are forced to fly again.

But the more reliable theory seems to be that most birds simply have nothing to eat in winter and, in addition, not all of them can survive the cold. Therefore, wild waterfowl, swallows, thrushes, starlings that feed on insects are simply deprived of food so necessary for them in winter. An indirect confirmation of this is that those species that can provide themselves with food do not fly away.

Those forest birds that feed on insect larvae hidden in the bark or berries growing wild on bushes may well feed in the winter months. Some species have adapted to the cities, and their food does not depend at all. These are pigeons, crows, sparrows and tits. They have adapted to life next to and now do not lack food either in winter or.

Some bird watchers believe that the factor that influenced the adaptability of birds to living conditions in cold weather is the risk of survival. Those species of birds in which the number of individuals surviving during the flight will be greater than during frosty wintering have chosen this method of preserving the species. Others, those for whom the flight threatens a large loss of individuals, chose to winter at home.

Related Videos

note

Due to the fact that crossbills feed on seeds of coniferous trees, their body has a very high percentage of resin. After death, the corpse of a bird practically does not decompose, but turns into a kind of tiny mummy.

Migratory birds are those representatives of birds that fly to the south from their usual habitats for wintering. Moreover, the same species can be considered both migratory and sedentary.

Instructions

All wild birds are conventionally divided into two groups: sedentary and migratory. You can notice that the sedentary remain for the winter in their usual habitat, and migrants go south with the onset of cold weather. What birds are considered migratory?

Migratory birds regularly move between nesting and wintering sites. Moreover, birds can perform both at short distances and at rather distant ones, which are thousands of kilometers from their habitat. How smaller size birds, the smaller the distance it is able to master at a time, although even the most can fly without stopping for 70-90 hours, covering a distance of up to 4000 km.

You cannot unambiguously classify some species of birds as sedentary or migratory. The fact is that there is in the behavior of different populations of the same species and birds of the same population. For example, the wren, which lives in Europe and the circumpolar Commander and Aleutian Islands, is settled, but the Canadian and North American representative wanders for short distances. And the wren, who have chosen permanent place habitat northwest of Russia, Scandinavia and the Far East, with the arrival of cold weather goes to the south.

The first heralds the onset of spring and returns to his usual habitat. 12 species of these birds are known to fly to Spain, France, Italy, Greece, Yugoslavia, Turkey, India and Pakistan for wintering. However, an ordinary starling, or as it is also called a blue jay, can move to the south in the same territory in winter, or it can live sedentary, so it cannot be unequivocally classified as a migratory m.

Rooks return to their lands almost simultaneously with the starlings. You also cannot classify this bird from the genus as migratory, since the rook is considered sedentary in the southern part of Eurasia, and migratory in the northern part. Swallows are considered migratory birds. They fly over the winter to Africa, Indonesia and South America... At the end of March, you may notice the appearance of finches, and by the end of April, blackbirds. In the first half of May he can tell about his return. This bird is known for its enchanting singing, which can be enjoyed all day, as well as from dawn until morning.

Migratory birds include lapwings, wagtails, robins, redstarts, orioles, forest pipits, and chiffchaffs. Most migratory birds leave us in flocks, but there are those that fly singly or in small groups. The cranes, lining up in a wedge, are flying very much. The ravens form a chain. In some representatives of birds, the young “breaks down” ahead of time, and in some, the males catch up with the females that have flown ahead. But most importantly, they always return to signify.

Some birds, with the onset of cold weather, leave their native lands, setting off on long journeys to the southern latitudes. This beautiful sight can be observed every autumn, and only the farewell cry of migratory birds will remind of feathered wanderers for some time.

Instructions

The reasons why some birds fly south are obvious: in winter it is difficult to search for food under the snow, and the ambient temperature becomes too cold. The fact is that birds are animals with a body temperature of 40 ° C on average. When cold weather comes to the region, some birds lack warmth, as their feathers and down are not enough to survive the severe frosts. But not all birds are cold in winter! For example, crows, tits, pigeons are not afraid of cold weather. They are, i.e. do not leave their native northern latitudes, but hibernate with a person. Such birds find food near garbage cans, in feeders, eat winter berries on trees, etc. The fact is that the amount of subcutaneous fat and feathers, as well as the structure of their body, are somewhat different from the physiology of migratory birds.

Most migratory birds are insectivorous creatures, the diet of which in winter period is reduced to zero. That is why migratory birds go where it never snows, and their food remains complete. Migratory birds include blackbirds, rooks, jackdaws, finches, dawns, warblers, buntings, and swallows. In the summer season, these birds feed on large insects ( May beetles,), in winter it is simply unrealistic to meet them in northern latitudes. For example, many swallows generally fly to the Mediterranean coast, and the most desperate of them go straight to Africa! Beautiful cranes also fly away to the south. Already in September, they are going on a long journey. These beautiful and graceful birds say goodbye to people until spring, at which time their beautiful and guttural cry is clearly heard in the sky, spreading throughout the clean and autumn air.

Birds such as hawks, kites, and kingfishers fly away to warmer regions one by one. But most migratory birds, nevertheless, leave their native northern latitudes in whole flocks. For example, cranes build a graceful and beautiful wedge in the sky, and ducks form oblique rows. Migratory birds also include such birds as lapwings, orioles, warblers, starlings, shrikes, nightingales, herons, swans, hoopoes and wagtails. Migratory birds return to their homeland at different times: some earlier, some later. For example, swallows are called heralds of spring, although there is an opinion that the rooks are the first to return to their native land. Since the earliest times, the return has personified the arrival of spring and warmth. Such a reputation as spring messengers made these birds popular favorites: they are happy, they are trying to feed them.

Sedentary, nomadic and migratory - these three main groups of birds are distinguished depending on how they react with movements to the changing seasons. If the sedentary live all year round in the same area, the nomadic migrants gradually migrate to the south, then the migratory ones winter far from their main habitats.

The question of bird flights can be divided into two:

1. Why do birds fly away to foreign lands every year?

2. Why do they come back, do not stay where they were not bad at all?

The questions are as interesting as they are difficult to answer!

For a long time, the migration of birds was explained by only one thing: in winter they are cold and it is necessary to change the climate. However, oddly enough, temperature alone is not a reason for flights. Feathers can provide good protection from the cold. For example, a canary can survive in freezing temperatures down to -45 ° C if it has enough food.

Now it is believed that in winter birds fly away to warmer regions from the winter lack of food. Birds use up the energy they receive from food very quickly, which means that they need to eat often and a lot. Therefore, when the ground freezes and food is difficult to find, especially for insectivorous birds, many of them go south.

The proof that the birds are "driven" to the south by the lack of food is the following fact: if food is in abundance, some migratory birds, even in cold weather, do not leave the places where they were born.

For example, a swallow leaves cold lands to spend the winter in Africa or Asia, under a cloudless summer sky. But why does it fly over the whole of Africa, then how can it find warm lands and closer?

It also happens: petrels fly from Antarctica to the North Pole. What kind of search for warmth is there!

And many tropical birds, which are not threatened by either cold or hunger, after feeding their chicks, go on long journeys. The gray tyrant, for example, (it looks a bit like our shrike) visits the Amazon selva every year and returns back to the West Indies when it is time to breed.

If scientists still do not understand everything about the reasons why birds break from their homes to warm lands, then the question of why they return back to the north from the fertile south is even more complicated.

It is believed that with the onset of the autumn season in the south, birds and their offspring are unfavourable conditions... For example, in the tropics and at the equator such thunderstorms are frequent that temperate countries simply do not know. In addition, the number of thunderstorm days there is much more than ours, dozens of times. Birds that fly to India and the subtropics are forced to flee from the dry season in the summer.

The snowy owl nests in the tundra, where summers are cold, the climate is humid and there are many lemmings that the owl feeds on. She spends winter in the forest-steppe of the middle zone. Can this owl stay for the summer in a hot dry steppe, where there is little food it is used to? Of course not. She flies off to her native tundra.

Part of the urge to return home can be attributed to internal changes in the bird's body. When the breeding period begins, the endocrine glands, under the influence of external stimuli, secrete special substances into the bird's body - hormones. Under the influence of hormones, the seasonal development of the gonads begins and passes. This, apparently, prompts the birds to migrate.

Another reason for birds to return home is that it is more profitable for birds to breed in mid-latitudes in summer, because here in summer the days are longer than in the south. Migratory birds are diurnal, and a long day gives them more opportunities to feed their offspring.

The nights are getting longer, the air is filled with freshness and frost, the plants are covered with the first frost, and the birds are preparing for long journeys. Yes, autumn has come and with it it is time to go to the warm shores.

Only not to us, but to our feathered brothers. They eat more and diligently accumulate fat, which will save them from the cold air and saturate the body with energy.

At one fine moment, the leader of the flock soars up and heads south, and after him all the other birds rush south. Some birds travel alone, because their natural instinct knows where to fly.

Of course, not everyone wants to fly south. So, such sedentary birds as, and feel great in the cold in winter.

They can fly to cities and feed on food that humans give them, and these species of birds will never fly away to hot countries. However, the overwhelming majority of birds tend to fly away.

Causes of winter migrations of birds

Have you ever wondered why do birds fly south and return back? After all, they could stay in one place and not make long and exhausting flights.

There are several theories about this. One of them is because winter has come - you say, and you will be partially right. It gets cold in winter and they have to change the climate.

But the cold itself is not the reason why birds leave their homelands. Plumage sufficiently protects birds from frost. You will probably be surprised, but you are able to live at a temperature of -40, if, of course, there are no problems with food.

Another reason for the flight is the lack of food in winter. The energy received from food is consumed very quickly, from this it follows that birds need to eat often and in large quantities. And since in winter not only plants, but also the earth freeze, insects also disappear, so it becomes difficult for birds to find food.

Evidence that why do many birds fly south due to lack of food is that when there is enough food to spend the winter, some migrants stay in their homeland during the winter cold.

However, of course this answer cannot be definitive.The following assumption is also controversial. The birds have a so-called natural instinct to change their habitat.

Some scientists suggest that it is he who makes them make long and dangerous journeys, and then return back a few months later. Of course, the behavior of birds is not fully understood and hides in itself many mysteries, the answers to which scientists have not yet found.

There is another interesting opinion why do birds fly south in autumn and come back. The desire to return home is associated with changes in the body during the mating season.

The glands begin to actively secrete hormones due to which the seasonal development of the gonads occurs, which prompts the birds to go on a long journey home.

The last assumption about why they seek to return home is based on the fact that for many birds it is much easier to raise offspring in the middle latitudes than in the hot south.

Because migratory birds by their nature they are active during daylight hours, then a long day presents more opportunities for them to feed their offspring.

Mysteries of bird migration

Reasons why birds fly south have not been fully studied, and it is unlikely that there will ever be a scientist who can prove the unambiguity of this or that theory of winter migration. Judge for yourself the absurdity of flights of some species of birds.

For example, he prefers to spend the winter on the African continent, where the sun warms in winter. Why would a swallow fly across Europe and Africa when there are warm places much closer? If you take such a bird as, then it flies from Antarctica to the North Pole, where there can be no talk of warmth.

Tropical birds in winter are not threatened by the cold or lack of food, but having raised their offspring, they fly to distant lands. So, the gray tyrant (can be confused with our shrike) flies to the Amazon every year, and when the marriage time comes, he flies back to East India.

It is generally accepted that upon the arrival of autumn for southern birds, not quite comfortable conditions... For example, in the tropical zone, as well as at the equator, there are often thunderstorms, and those that cannot be found in countries with temperate climate... Birds flying to places of a subtropical climate, in summer period leave territories with a dry season.

So, for the white, the optimal nesting place is in the tundra. Cool summers and enough food, for example, makes the tundra ideal place her habitat.

In winter, the range of snowy owls changes to the forest-steppe of the middle zone. As you probably already guessed, the owl will not be able to exist in the hot steppes in the summer, and therefore in the summer it returns to the tundra again.

Do you know why birds fly south? Do you think that birds fly where it is warm, where it is easier to survive in winter? Any birdwatcher will tell you that this is not entirely true.

There is an opinion that birds do not prepare for flights in advance, but go to warmer regions only when they begin to feel the approach of cold weather. Thanks to numerous observations, ornithologists were convinced that most birds fly south when there are still no signs of approaching cold weather and lack of food. For example, pied flycatchers begin to wander in July, as soon as the chicks of the second clutch become independent. Conversely, some birds return when there is still snowfall and frost and when there is not enough food. At this time, the death of birds that have already arrived home is often observed.

Thus, the version that the birds are driven to warmer regions by hunger and cold disappears.

The real reason why birds fly south

It turns out that birds, long before departure, begin to prepare for it, to tune in. They undergo a physiological restructuring of the body. And, finally, birds sitting in cages do not feel either hunger or cold all year round, in autumn and spring they begin to show anxiety. This means that bad weather, cold and hunger do not force the birds to fly south. A powerful instinct developed over millennia makes them fly. And the "signal" for flights is given to them by the "migration impulse". Moreover, the "mechanisms" that make birds fly in one direction or another are different: one for wintering, and another for wintering home.

And, finally, why do birds return after they fly south? After all, they have a presentiment (let's say that this is so) unfavorable living conditions. Let us also assume that they "have a presentiment" that favorable conditions for life have come in their homeland. But why go on risky and burdensome travel, if the birds already live in warmth, if they are full? Let them live permanently in Africa or in the south of Europe. And they still fly back! And it is here, in their homeland, that nests are built and chicks are raised. Is this the key to bird flights to the south? Why don't they breed chicks in hot countries?

The thing is that in hot countries all birds - both adults and young - cannot survive. Indeed, in wintering places, a lot of birds from different parts the globe. You can still feed yourself, but you won't be able to feed the chicks. Even if there is enough food for the first brood, then the next (after all, the number of individuals will grow exponentially) will begin to starve significantly, and the third will probably die. However, the third may not exist (just like the second or even the first): there will be nowhere to build nests!

That is why, having overwintered in favorable conditions in the south, the birds fly to their homeland: it has already become warm there, insects have appeared, and most importantly, there are places for nesting. Birds, of course, do not realize this, but the powerful instinct that drives them has been working correctly for many millennia. He gives the order to the birds to fly south, survive the unfavorable conditions, and then orders to return and fulfill the main thing - to breed. And it does not matter for them whether it is still cold at home or fine days have already come - the birds fly back, obeying the order of the "inner voice" - the instinct of procreation.

Why is it important for birds to fly south?

And now imagine the following: evolution, "worked" in such a way that all birds stopped flying south and adapted to winter in their homeland. Adapted to endure the cold, find food in the winter. Many hibernating birds die (out of 10 tits until spring they survive in best case 1-2). And if everyone hibernated, even more would die. Competition for food will increase, strong individuals will oust the weak. In the spring and summer, there will be competition for nesting sites. And again, the species adapted to survival will crowd out the less adapted.

In general, a tough fight will begin among the birds. Who would have won in it is unknown, but it is certain that the entire avian genus will lose. Therefore, for many millennia, birds have been flying south. And flying for birds is the most important of all the adaptations that allow them to survive on the planet.

And now I suggest you watch online beautiful video about the flight of birds to warmer regions.

The term "migration" comes from the Latin word "migratus" which means "to change". This word has special meaning when it refers to. Migration is the movement of animals from one region (or) to another. It occurs at certain times or seasons of the year. Animals migrate to reproduce, grow, seek food, or avoid cold weather. For many, migration occurs twice a year. They fly away in the fall and return again in the spring.

What makes a bird a bird?

All bird species have feathers. There are other characteristics common to the bird class, but feathers are the only trait completely unique to these animals. Many might say that flying makes birds special, but did you know that not all birds fly? Emus, cassowaries, and rhea are birds that do not fly. Flightless birds such as penguins are excellent swimmers underwater.

Birds have many interesting devices that allow them to fly. Lightweight yet strong bones and beaks are adaptations for weight loss during flight. Birds have unique eyes, ears, legs, and can build nests. Some species are capable of making beautiful sounds.

Why do birds migrate?

Many birds look for places in which it is warm, there is an abundance of food, as well as the opportunity to reproduce and protect themselves from predators. In, especially in, the climate is warm enough, so birds can find a sufficient amount of food throughout the year. The steady daylight gives them plenty of time to eat every day, so they don't need to fly somewhere to find food.

How do birds navigate?

Navigation is difficult because it requires birds to understand three things: their current location, their destination, and the direction they must follow to get to their destination.

Some birds use the sun and stars to navigate. Others are guided by features such as rivers, mountains, or coastlines. Some birds may even use their sense of smell. Though birds are also able to move on cloudy days and fly through where there are no clear landmarks. So how do they do it?

Scientists have come to the conclusion that birds sense the earth's magnetic field through magnetoreception. Birds contain so-called magnetite, which is an iron-containing mineral that acts like a compass. Other scientists believe that birds can see the magnetic field with their own eyes. Science is not yet fully aware of the orientation of birds, but they probably use several ways to navigate.

Why do birds fly in a wedge?

A flock of birds does not fly like a wedge by accident. Big birds such as geese and ducks form a wedge to reduce air resistance. The wedge allows flocking birds to fly farther and more efficiently than birds flying alone.

When flying in a wedge, efficiency is increased by 70%. The lead bird and the trailing bird are the hardest, while the birds in between benefit from the flapping of other birds.

Besides improving flight, this technique is also useful for bird-to-bird communication. Wedge flight allows birds to fly close to each other, as well as hear and see their relatives. They transmit information to each other (through sounds) and can stick together.

The danger of migration

Occasionally, birds must fly through harsh habitats such as deserts where water is scarce or oceans where there is no place to rest or feed.

Even if they find food and water, the birds need to land on the ground, where they risk becoming someone's prey.

There can be many predators on the migration path. Depending on their size, migratory birds become prey, foxes, wolves, humans and other animals. Some birds can be attacked more large species birds during the flight. Sometimes difficult weather conditions make it difficult to fly and even lead to death. It happens that birds collide with planes, which is dangerous both for themselves and for the planes.

How do bird watchers study birds and their migration?

Ringing birds is one of the methods used to study them. Scientists put a small, individually numbered metal or plastic ring on the bird's leg or wing. They also use special nets, known as mystical nets, as a way of capturing wild birds for research.

Thus, bird watchers can capture the same bird several times, measure and weigh it, and collect other important information over time. Scientists sometimes use satellite data to track bird migration routes.

Fascinating facts

Arctic tern has the longest known migration route. It flies about 70,000 km a year between breeding grounds in the Arctic and winter sites in.
Birds can fly at speeds ranging from 30 to 80 km / h.
Large birds fly faster than small species.
For 10 hours of flight, some birds cover about 650 km.
Radar surveys show that most flights take place at altitudes less than 3 km, but some birds have been recorded at altitudes over 8 km.
Birds flying long distances fly at higher altitudes than those flying short distances.

If you find an error, please select a piece of text and press Ctrl + Enter.