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The fact that migratory birds living in Europe fly to Africa for the winter does not surprise anyone. But why birds living in Asia migrate to this continent amazes even scientists: after all, it would be much easier for birds to fly to the southern regions of their continent. For example, representatives of the passerine order annually fly from the northeastern coast of the Pacific Ocean to the African continent, flying over the entire Siberia. This mystery has still not been solved and, it seems, scientists will have to tinker with it for a long time.
When do birds fly away?
Regardless of what reasons birds find for migrating (and there are a lot of such reasons and the matter is not limited to hunger), the question remains “how do birds know that it is time to leave their homes and change their place of residence?” Observations by ornithologists have established that birds fly away at approximately the same time every year, and precisely when the seasons change. But what is the most reliable, unmistakable sign of this change? Most would agree that it is a change in the length of the day.
The breeding season for birds occurs in the summer, and this is also closely related to migration. Only in this case, the birds move in a northerly direction. Certain glands in the bird's body begin to produce substances related to reproduction, this happens in the spring, and the bird, feeling the need to procreate, heads north, where summer begins.
Consequently, the disappearance of food and a change in the length of the day give the bird a signal that it is time to go to warmer climes. And in the spring, the instinct of procreation tells the bird that it is time to fly north. Of course, there are other factors that we do not yet fully understand, but those listed above are the key that will allow us to unravel the mystery of bird migration.
Bird compasses
Once the course is known, you can follow it for a long time only with the help of a compass. Depending on the circumstances, birds confidently use at least three different types of “compasses.” In the daytime, birds accurately determine the position of the cardinal points by the sun. Even a light veil of clouds does not prevent this, as long as it still allows you to feel the position of the star in the sky. At night, the solar “compass” is replaced by a star “compass”, and many birds that make night migrations have also achieved great success in the art of using it. When the weather completely deteriorates and the sky is covered with clouds around the clock, a magnetic “compass” comes to the rescue of feathered travelers, which they also manage very skillfully.
Thus, to the question of what kind of “compass” feathered travelers use, scientists have an almost exhaustive answer. The situation is worse with understanding what the “navigator’s map” of birds is and what methods they use to mark their location on it. Let us remember that sailors learned to do this for real only with the advent of precise measuring instruments.
First of all, a chronometer - a watch with a very precise movement, allowing at a strictly defined hour during a multi-month voyage to track the height of the luminaries above the horizon and their azimuth - that is, their location in relation to the direction to the north. The position of the luminaries is determined using a sextant - a rather complex instrument, without which not a single long-distance ship has left the port over the past three centuries. To “get the location” of a ship, it is necessary to make at least two measurements of the altitude or azimuth of the stars - in any combination.
Having obtained the necessary figures with the help of navigation tables, which partially free the navigator from complex calculations, he can determine, with an accuracy of several miles, the geographic longitude and latitude under which the ship was located at the time of measurements. More accurate, but disproportionately more expensive methods of navigation, indicating the position of a ship or aircraft with an accuracy of tens of meters, became possible only with the advent of space technology.
Solar and star compasses
Thus, by the position of the Sun or stars in the sky, you can not only maintain a course, using the luminaries as a replacement for a compass, but also determine your position on the surface of the planet, using the luminaries as place indicators. It is now firmly established that birds have an innate ability to use solar and stellar “compasses”, thanks to the presence of precise “internal clocks” that allow them to choose the right direction at any position of the stars during the day.
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Penguin migration
Interestingly, birds that absolutely cannot fly are also prone to seasonal migration, among them emperor penguins. When summer ends in Antarctica, they swim into the Indian Ocean, with some individuals even swimming as far as 47 degrees south latitude.
Scientists say that the reasons for their migration include not only the harsh conditions of the Antarctic winter, but also the long polar night, during which it is easier for the predator to sneak up on the penguins. Interestingly, when living outside the home, penguins prefer to eat crustaceans rather than fish.
From an early age we know that in the fall many species of birds begin to appear in the sky, heading south. But often both children and adults find it difficult to answer what kind of birds they are. But before answering this question, let's find out what groups birds are divided into.
Scientists have divided all existing bird species into two groups. One included migrants, and the other wintered. All birds are warm-blooded, that is, their average body temperature is about 41 degrees.
Many people also believe that they have to leave their homes because they may freeze in winter. But this is not the main reason, it’s just that in winter it will be very difficult for them to find food for themselves. Thus, wintering birds include those species of birds that are able to get food for themselves during the cold season.
These species include woodpecker, capercaillie, tit, nuthatch, jay, pika, hazel grouse, and black grouse. In addition to them, some inhabitants of the cities also remain for the winter, who will be able to get food for themselves at any time.
Types of bird movements equated to migrations
In the last decade, fierce debate among ornithologists over the question of whether one-time moments of bird movement should be considered migrations ended in a peaceful agreement: some cases when birds found themselves in a new territory, but did not return, are also now called migration.
This is, first of all, introduction - the relocation of birds to a new territory with the help of humans and their subsequent permanent residence in a new place.
Vivid examples of introduction are the starling and the sparrow: the first moved with the help of humans to America and feels great there, the second, on the contrary, once moved to Europe.
Introduction should not be confused with invasion, which is also now recognized as a type of one-way migration. This concept implies the relocation of living beings, which occurred without human intervention for some natural reason.
For example, this happened with hummingbirds - which once inhabited Europe, they now live only in America, and not a single living settlement of these birds has survived in the old place.
Sensational discovery!
However, on May 21, 1822, a sensation spread around the world! Near Mecklenburg, Germany, an 80-centimeter arrow was found in the body of a dead stork, piercing the bird’s neck. The arrow was not from here and belonged to one of the African tribes. A desperate brave man with an arrow in his throat managed to overcome the entire migration route, returning home from the equatorial wintering grounds.
This story shed light on the mysterious disappearance of birds in winter. A stuffed specimen of the famous arrow stork can still be seen in the zoological collection of the University of Rostock.
Repeated reports of white storks with African arrows in their bodies helped make the discovery: European birds winter in equatorial Africa. However, ringing, which naturalists began to carry out since the 90s of the 19th century, made it possible to accurately determine the places where birds fly to for the winter.
Migratory and nomadic
There are fundamental differences between migratory species and nomadic ones. The first group will necessarily leave their homeland with the onset of cold weather. As for nomadic flocks, they always have a choice whether to fly away or stay. It depends on the comfort level of the season, weather conditions and food. In warm winters, rooks, jackdaws, siskins, bullfinches, nuthatches and other nomads remain in their homes.
As for rooks, swans, nightingales, ducks, larks, they have no choice and therefore are classified as migratory. For this reason, you will never see them during the cold months, even if the winter is mild.
Wintering places chosen by Russian birds: Southern regions of Asia, Africa, as well as the warm regions of the European continent.
Causes
Birds are warm-blooded creatures, their normal body temperature is about forty-one degrees. It would seem that they should feel great in the winter season too. This is true, but when it’s cold, it’s difficult for many of them to get food, and for some species it’s completely impossible.
But there are still those who fly away due to frost. Therefore, sometimes risking their lives, birds fly to places where they can keep most of their flock and have offspring without any problems. Naturally, many fly away not because of a lack of food, but also because of the approaching cold weather.
What birds fly south in the fall not for food? They are called migratory. These are birds such as swallow, swift, lapwing, chaffinch, redstart, oriole, chiffchaff and others.
What other birds fly away? Of course, plovers, rooks, siskins, starlings, buntings, shrikes, lapwings, tree pipits, warblers, robins, nightingales, black-headed grosbeaks, flycatchers, herons, wagtails, swans, hoopoes, storks, larks, geese, ducks, cuckoos, robins .
But there are also sedentary birds; they do not leave their homeland all year round. Walking around you can see sparrows, titmice, jays and woodpeckers.
There are also birds that do not fly south in the fall, but migrate. They move to another place only when the conditions in the previous one have become unsuitable for living. On the territory of Russia, these birds include the jay, bullfinch, crossbill, tit, nuthatch, shura, siskin, waxwing and others. Typically, such species live in the highlands, but with the onset of severe cold they settle in nearby valleys.
It’s clear which birds fly south in the fall, but why do they go there? They usually move to places where conditions resemble their area. For example, if they live in the steppes, then they will fly into fields and meadows, if in the forest, then into the thicket. The timing of their migration may be affected by the weather, but they usually do so at the same time. Autumn migration begins when the chicks grow up. Birds gather in flocks, and some leave their homes alone.
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Winter is the most difficult season of the year for birds, as well as other animals. In winter, the length of the day and the intensity of light are sharply reduced, the temperature drops, and the feeding and other living conditions of birds deteriorate. Among the adaptations that birds have developed over many millennia to survive this unfavorable season of the year, seasonal migrations are of paramount importance, i.e. moving to places with a favorable environment. Seasonal migrations in one form or another are characteristic of almost all birds of cold and temperate latitudes, where seasonal changes in living conditions occur. In passing, we note that the latter also occur in the arid regions of the tropics and subtropics, in which seasonal bird migrations are also observed.
The severity and scope of seasonal migrations are closely dependent on the degree of seasonal fluctuations in living conditions and, first of all, on the duration and severity of winter. The longer and more severe the winter, the fewer bird species are able to survive it and the greater the number migrate to other climate-milder areas. Therefore, in northern latitudes, with their harsh, long winters, seasonal migrations are more pronounced than in more southern latitudes. This is clearly visible in the attached diagram, which shows that as we move from northern to southern latitudes, the proportion of migratory species decreases and the proportion of nomadic and sedentary species increases.
Seasonal migrations are characteristic of birds of almost all geographical regions with distinct seasons of the year, however, they manifest themselves differently in different species. Some of them lead a semi-sedentary lifestyle, making minor movements in the winter around the nesting area (grouse, hazel grouse, etc.). Others undertake longer migrations in different directions in winter (tits, woodpeckers, etc.). Still others regularly fly for the winter to relatively close southern latitudes (crows, rooks, goldfinches, siskins, some ducks, etc.). Finally, the fourth make long-distance migrations to the equator region or the southern hemisphere (swallows, swifts, many waders, etc.). Migration is expressed differently even among species living in the same area, with the same seasonal fluctuations in the environment. Thus, the common bunting living in the Moscow region in winter is limited to small migrations, and from the same places the forest pipit flies to the south for the winter. The pied flycatcher flies from near Moscow to spend the winter in Portugal and North Africa, and the great tit, which often nests in neighboring hollows, migrates mostly within the central regions of our country.
The varying degrees of severity of seasonal migrations are explained by the fact that different species have adapted differently to experience seasonal fluctuations in the environment. Some species cannot withstand the deterioration of living conditions that occurs in winter in northern and temperate latitudes, and fly south to places with favorable conditions for the entire winter period. Others, in the process of their historical development, acquired certain adaptations to survive the critical winter period and spend the latter in the same latitudes. And the more perfect these adaptations are, the less pronounced migrations are and vice versa.
To illustrate what has been said, let us consider the adaptations of birds to the changes that occur in winter in such important environmental conditions as food, temperature, protective and light.
The winter season brings enormous changes to the feeding conditions of birds of high and temperate latitudes. First of all, the total reserves and range of feed are sharply reduced. The entire vegetative parts of plants and low-growing shrubs (lingonberries, blueberries, etc.) hidden under the snow cover fall out as a food base for birds. The vast majority of insects and other invertebrate animals disappear. Amphibians, reptiles, and fish from frozen bodies of water become completely inaccessible. It becomes very difficult to catch mouse-like rodents and other small animals hiding under deep snow cover or hibernating.
The winter food available to birds at these latitudes remains mainly seeds, buds, needles, and terminal branches of trees and shrubs; in small quantities, seeds of tall herbaceous plants; insects, their eggs, larvae and pupae hidden in shelters on the trunks and branches of woody plants; small species of mammals and, finally, various kinds of waste and refuse from human agriculture in their settlements, landfills and on roads. In general, the quantitative reserves of plant food predominate over animal food, and moreover, obtaining the latter in winter becomes more labor-intensive.
Under the influence of such impressive seasonal changes in feeding conditions, many birds are deprived of their usual food for the winter and migrate to warmer climatic zones. Only those who have adapted to obtaining and using the food available during this season remain to spend the winter here. These adaptations are mainly expressed in: changing food according to the seasons, changing places and methods of searching for food, and storing food.
Seasonal change of feed , i.e. the transition to feeding on those foods that are most abundant and available in a particular season of the year is one of the most important adaptations characteristic of many birds of northern and temperate latitudes. To survive winter, switching to plant foods, which are more abundant during this season of the year, is of particular importance. Species whose diet in winter consists entirely of plant foods include black grouse, hazel grouse, chaffinch, siskin, goldfinch, buntings, skylark and many others. In addition, many species, while remaining mainly animal-eating, in winter partially switch to plant foods. These species include: great spotted woodpecker, nuthatch, great tit, Muscovy and others. Finally, some species that winter in human settlements switch entirely or partially to feeding on household waste (sparrows, jackdaws, crows, etc.).
The diagram below shows that the vast majority of species nesting near Moscow, which have the ability to 100% or partially (86-64%) change the composition of food according to the seasons of the year , do not make long flights, but lead a sedentary, semi-sedentary and nomadic lifestyle, or undertake relatively short flights within the same latitudes. The vast majority of birds from the last group winter in a climate zone with an average January temperature of -20 and above. Consequently, the transition to feeding on plant foods in winter weakens the scope of seasonal migrations and strengthens the element of sedentism in birds.
The transition to winter feeding on plant foods is most fully accomplished in species that are predominantly herbivorous than in species that are predominantly animal-eating. Therefore, the former have a more stable food supply in winter than the latter and are less susceptible to seasonal migrations. Thus, in the Moscow region, all sedentary, semi-sedentary and half of the nomadic species are predominantly herbivorous, while the absolute majority of migratory species are predominantly animal-eating. Among the birds wintering in northern and temperate latitudes, the majority are predominantly herbivorous. In the Pechora-Ilichsky Nature Reserve (Komi Autonomous Soviet Socialist Republic) there are 68% of them, in the former Volga-Dubnensky Nature Reserve (Moscow region) 64%.
Since in winter food from herbaceous plants disappears under the snow, only species that search for food in trees can winter in latitudes with deep snow cover. Birds that feed on the ground are forced to fly to latitudes where there is no snow cover. The exception is species that feed on household waste in human settlements in winter (sparrows, magpies, crows, etc.).
The noted influence of snow cover also applies to animal-eating species that forage on the ground. Of the latter, not only those who feed on invertebrates (insects, worms, etc.) and “cold-blooded” vertebrates (frogs, lizards, fish, etc.), who fall into torpor in winter and disappear under deep snow, fly south and ice cover, but also feeding on terrestrial “warm-blooded” animals (mammals), in particular mouse-like rodents. Although mouse-like rodents do not hibernate and are active throughout the winter, hunting them in the snow cover is difficult, and mouse-eating predators (harriers, buzzards, some owls) are not able to feed themselves.
Therefore, the absolute majority of birds wintering in the zone of continuous snow cover belong to species that forage above the ground - in trees and in the air (bird-eating predators). In the former Privolzhsko-Dubnensky Nature Reserve, they make up 81% of all wintering birds. The remaining 19 species live in human settlements and feed on household waste.
Changing places and methods of searching for food is characteristic of quite a few species of birds of northern and temperate latitudes. Thus, black grouse, hazel grouse, capercaillie, and willow partridge feed exclusively on the ground in the summer, but in winter they switch to feeding on woody food - buds, catkins, pine needles, turning from “terrestrial” to “arboreal” bird species. In summer, these birds have bare toes; in winter, they are edged with a horny, comb-like fringe, which helps the bird to stay on icy branches and move along them. Magpie, crow, and common bunting live in forests in the summer, where they collect food on the ground. In the winter, they move to human habitation, where they feed in garbage dumps and landfills. The Great Spotted Woodpecker in summer hollows out insects and their larvae in the bark and wood of tree trunks; in winter it looks for cones on thin branches, feeding on the seeds of coniferous trees. A number of tit species in summer peck insects from the surface of leaves and thin branches, in winter they inspect trunks and hollow out insects from their shelters,
Birds that have the ability to change places and methods of obtaining food usually do not make significant migrations and live in the same latitudes all year round.
Food storage is observed almost exclusively in species wintering in northern and temperate latitudes. It is well known for the taiga bird nutcracker, which hides a significant amount of pine nuts in separate piles under moss, tree roots, etc.; jays, which hide acorns under the roots and in the hollows of trees in the fall. The pygmy owl collects various small birds and mouse-like rodents in hollows in the fall and first winter. Crows and magpies make small reserves of food, hiding them in fallen leaves or in the snow. The tufted tit, the black-headed tit, and the black-headed chickadee are widely practiced in the fall to store seeds of pine, spruce, fir, etc., placing them in the cracks of the bark under twigs, lichens on trees, etc. The nuthatch creates reserves for itself by placing maple lionfish, beech nuts, etc. in cracks in the bark of trees.
Birds use stored food during the hungry winter period, and each individual finds only part of its reserves and uses food stored by the entire population of the species in a given area. Birds stocking food in winter do not migrate far and winter in the same northern and temperate latitudes.
Ambient temperature plays an important role in the life of birds. Cold weather in winter sharply increases the heat transfer from the bird's body and to maintain the normal temperature of its body requires, on the one hand, an increase in the amount of food consumed, and on the other, special devices. Such devices that reduce heat transfer and promote normal heat exchange include: increasing the density and length of plumage, using special shelters for overnight stays and protection from bad weather.
The feather cover of birds reduces heat transfer from the body and maintains its constant temperature. In accordance with seasonal fluctuations in environmental temperature, changes in the density of plumage and its length are observed in birds. These changes are especially significant in species wintering in cold climate zones. Thus, in siskins caught in February and March, the number of feathers in the plumage was equal to 2107-2368, while in the specimen caught in June it was only 1439; in one species of tits in February - 1704, in June - 1140.
The heat-insulating role of plumage increases in winter due to the lengthening of the feather itself, the development of the downy part and the side stem. This is clearly seen in the example of the white partridge wintering in a cold zone. The length of the feather from the back is on average 5.4 cm, in summer - 4.7 cm; the downy part of the feather is 2 and 1 cm, respectively, and the length of the side trunk is 3.4 and 2.7 cm. The same can be said about feathers from other parts of the body. In addition, the beards of winter feathers are longer and located somewhat more often than those of summer feathers. As a result, the downy part and side stem of the winter feather of a partridge are thick, like felt, and retain heat well. The partridge's summer plumage is shorter and looser, which contributes to better heat transfer.
The lowest temperatures in winter fall at night, when most birds rest and stop feeding. Consequently, the most intense heat transfer from the body coincides with the period of least activity of the body and a decrease in the level of oxidative processes due to the cessation of food intake. This makes normal heat exchange difficult and makes the bird vulnerable to night cold. In this regard, birds wintering in cold climate zones use various types of shelters for overnight stays, which protect them from low temperatures and help reduce heat transfer. Some birds also resort to this kind of shelter for protection from bad weather (blizzards, blizzards, etc.) during the daytime.
A number of species burrow into the snow at night during severe cold and bad weather. This is observed in black grouse, wood grouse, hazel grouse, white and gray partridges, etc. Snow is a poor conductor of heat and has good heat-insulating properties. According to observations in the Pechora-Ilych Nature Reserve, when the air temperature fluctuated from -16 °C to -39 °C, the snow temperature at a depth of 20 cm changed only from -10 °C to -16 °C. The hazel grouse spends the night in snow holes all winter, spending up to 20 hours a day in them during the cold months (January-February) and flying out to feed for several hours during the warmest time of the day.
The black grouse spends more time outdoors, but in severe frosts it buries itself at a shallow depth in the snow many times a day to warm itself up. In winters with little snow, when birds cannot take refuge in it, mass freezing of black grouse, hazel grouse and other birds using snow shelters is often observed.
Hollow-nesting forest birds (woodpeckers, nuthatch, tits, etc.) take refuge in hollows for the night and in bad weather. The latter are also used by owls during rest hours (i.e. during the day). Sparrows, jackdaws, some tits, buntings and others wintering in human settlements climb at night under roofs, behind window frames, under eaves, etc., often taking advantage of some of the warmth of human habitation.
A number of small birds are observed to roost together in groups on cold winter nights. Under roofs and in other places, pikas were observed roosting in groups of up to 20 individuals, huddled together in a dense heap. Wrens can gather up to 30-40 individuals in one shelter. Group roosting is observed in the woodpecker hollows of woodpeckers and small species of tits. Some species (jackdaws, rooks, crows), spending the night openly in trees, gather in large dense groups, huddled close to each other. Group roosting helps reduce heat transfer and preserve body heat for each bird.
The described adaptation to withstanding winter cold at night is widespread. Of the 37 species wintering on the territory of the former Privolzhsko-Dubnensky Nature Reserve, 24 species (65%) use special shelters for overnight stays. Other species spend the night under the protection of dense tree branches or other shelters.
Low temperatures during long winter nights are one of the important factors limiting the number of wintering birds in northern and temperate latitudes. Species adapted to withstand cold nights remain here for the winter.
In winter, the length of the day is sharply reduced, reaching 6-7 hours in the middle zone of our country, and even shorter in the north. Many birds, even if there is food, cannot provide themselves with the necessary amount of food in a short day and migrate to latitudes with longer daylight hours for the winter. Normally, only those species that have developed certain adaptations to poor winter light conditions can winter here. From this kind of adaptations, one can indicate an increase in daily activity and the rate of search for food.
If in the summer most birds begin feeding a considerable time after the morning dawn, and finish long before the evening twilight, and even rest in the middle of the day, then in winter the situation changes. In winter, birds are active from morning to evening twilight, feeding continuously all day, limiting themselves to rest only at night. The rate of search for food also increases, which is especially noticeable in the example of tits and kinglets that winter with us, the speed of movement of which when searching for food in winter is higher than in summer, and higher than that of any other migratory small birds.
Protective conditions, i.e. various kinds of shelter from enemies and bad weather play an important role in the life of birds. Winter brings great changes to these conditions and worsens them. In summer, birds can hide in the dense foliage of trees, tall grass in a meadow, thickets of aquatic plants in ponds, etc. In winter, the leaves on the trees fall, the grass dries out and is hidden under the snow, and the protective conditions for birds deteriorate sharply. Birds remaining for the winter move to more protected places with a large number of shelters. Such habitats are forests and human settlements. It is typical that birds wintering in the Moscow region stay exclusively in these two types of habitat. It is also significant that the birds living here in winter keep their eyesight in coniferous and mixed forests, being much less common in deciduous ones. This is explained not only by the fact that there is more food here, but also by the fact that birds find more shelter in these types of forests. The dense needles of the trees hide them well from the eyes of enemies, protect them from wind, snowfall and other adverse weather influences.
From all that has been said, it is clear that many birds of northern and temperate latitudes have various adaptations to survive unfavorable winter conditions and participate in seasonal migrations much less frequently than those without these adaptations. They do not require long flights; they can successfully live all year round in the same places and latitudes. All of them are either sedentary, nomadic, or weakly migratory. These species express one way of adaptation to surviving unfavorable seasonal environmental factors, leading to the emergence of a tendency to settle down. Those species that were unable to adapt to surviving a harsh winter in place chose a different path: they make long-distance flights to other favorable climatic zones and latitudes, thereby avoiding the harmful influence of adverse factors that appear in the nesting area in winter. Thus, the nature and degree of adaptation to surviving the critical seasons of the year with their unfavorable environmental factors determine the nature and scope of seasonal migrations, the degree of sedentism and migratory behavior in different bird species.
A. Mikheev, Candidate of Biological Sciences
Magazine "Hunting and Hunting Management", No. 2, 1960.
Bird signs for spring
Early rooster crowing in severe frosts is a harbinger of warm weather. A bullfinch chirps under the window - a thaw. The white wagtail, a recognized harbinger of ice drift, always arrives on the eve of the opening of rivers.
Rook on the mountain - spring is in the yard. The rook has arrived - the snow will melt in a month. The seagull has flown in - soon the ice will melt.
The rooks arrived before March 14 - the snow will melt early. The rooks fly straight to the old nests - there will be a friendly spring, the hollow water will run away all at once. The rooks arrived early - in anticipation of a warm spring.
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The lark began to sing - it’s time to go out into the arable land. When the nightingale begins to sing in mid-May, spring will come together. A migratory bird flies together - and spring will be friendly. The early arrival of cranes means early spring.
Post-breeding period
Under the influence of external factors, bird feathers wear out and lose their color. Their edges become very thin, and the hooks connecting the beards of the fans are undermined. The flight and tail feathers, which play a major role in flight, become especially frayed.
This all worsens the flying abilities of birds and weakens the heat-insulating function, so one of the most important stages in the annual life cycle of birds is the change of plumage.
During the molting process, the seasonal and age cover changes . The “outfits” of each season will differ in the density of plumage and color. During the autumn moult, the number of feathers increases and the downy parts of the plumage become stronger.
Upon completion of breeding, the sedentary lifestyle of most birds ceases: they leave their inhabited territory. At first, broods do not fly far from the nest, but when families are organized into flocks, migrations occur over longer distances. Birds focus on places rich in food, since the leading need of the body during this period becomes the need for increased nutrition.
Post-breeding movements (migration) are widespread and represent a common phenomenon in the life of nomadic and migratory birds. In some species it occupies a significant share of the annual cycle.
Why do birds fly south?
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 the time has come to head to warm shores.
Not for us, but for our feathered brothers. They eat more and diligently accumulate fat, which will save them from cold air and saturate their body with energy. At one point, 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 all birds want to fly south. Thus, such sedentary birds as sparrows, magpies, tits and crows feel great in the cold in winter.
They can fly to cities and feed on the food that people give them, and these types of birds will never fly away to hot countries. However, the overwhelming number of birds still want to fly away.
Reasons for winter bird migration
Have you ever wondered why birds fly south and come back? After all, they could stay in one place and not make long and grueling flights. There are several theories about that. One of them is because winter has come - you will say and you will be partially right.
In winter it gets cold and they are forced to change the climate. But the cold itself is not the reason why birds leave their native lands. The plumage sufficiently protects birds from frost. You might be surprised, but a canary is able to live at a temperature of -40, unless, of course, there are problems with food.
Another reason for birds migrating is due to lack of food in winter. The energy obtained from food is consumed very quickly, which means that birds need to eat a lot and often. And since not only plants, but also the ground freeze in winter, insects disappear, so it becomes difficult for birds to find food.
Evidence of why many birds fly south due to lack of food is that when there is enough food to survive the winter, some migratory birds remain in their homeland during the winter cold.
However, of course this answer cannot be final. The following assumption is also controversial. Birds have a so-called natural instinct to change their habitat. Some scientists suggest that it is he who causes them to make long and dangerous journeys, and then return back after a few months.
Of course, the behavior of birds has not been fully studied and hides many mysteries, the answers to which scientists have not yet found. There is another interesting opinion why birds fly south in the fall and return 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 sex glands occurs, which encourages the birds to set off on a long journey home.
Since migratory birds are by nature active during daylight hours, long days provide them with more opportunities to feed their young.
Mysteries of bird migration
The 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 one or another theory of winter migration. Judge for yourself the absurdity of the flights of some species of birds.
For example, the swallow prefers to winter on the African continent, where the sun warms in winter. Why would a swallow fly across all of Europe and Africa when there are warm places much closer? If you take a bird like the petrel, it flies from Antarctica to the North Pole, where warmth is out of the question.
Tropical birds in winter are not threatened by either cold or lack of food, but after raising their offspring, they fly to distant lands. Thus, the gray tyrant (can be confused with our shrike) annually flies to the Amazon, and when mating time comes, it flies back to East India.
It is generally accepted that with the arrival of autumn, conditions are not entirely comfortable for southern birds. For example, in the tropical zone, as well as on the equator, there are often thunderstorms, and those that cannot be found in countries with a temperate climate.
Birds migrating to places with subtropical climates leave dry season areas in the summer. Thus, for the snowy owl, the optimal nesting place is in the tundra. Cool summers and ample food, such as lemmings, make the tundra its ideal habitat.
In winter, the range of snowy owls changes to the forest-steppe of the middle zone. As you probably already guessed, the owl cannot exist in the hot steppes in the summer, and therefore in the summer it returns to the tundra again.
Mechanisms of bird migration
Magnetic poles of the earth
With a certain degree of convention, the Earth can be imagined as a giant magnetized ball. At every point on the surface of the Earth there is a magnetic field, the direction of which can be easily determined using the compass needle, which always faces the magnetic pole. Let us recall that the magnetic poles of the planet lie somewhat away from the geographic poles marked on maps or the globe, through which the Earth’s rotation axis passes.
The needle of a conventional compass moves only left and right, therefore it shows the direction of only the horizontal component of the field, being directed along the magnetic meridian to the Earth's magnetic pole. But the forces of terrestrial magnetism act not only in the horizontal plane, but also towards the center of the planet, that is, the magnetic field also has a vertical or, as they say, gravitational component. If a compass needle could move in all directions, including up and down, its position would change noticeably as it moved from the equator to the poles.
At the equator, it would be located strictly parallel to the surface of the Earth, that is, absolutely horizontal, pointing its magnetized end strictly to the north. As we move from the equator, its deviations from the horizontal would become more and more noticeable, and finally, at the north pole, the arrow would turn to the center of the planet, that is, it would stand vertically. At the south magnetic pole, the needle will also take a vertical position, but its magnetized “north” end will face straight up. Thus, a compass with a similar device can be used not only to indicate the direction north, but also to determine its position on the meridian, that is, as an indicator of latitude.
VIDEO: How do migratory birds fly?
From today, the day of Gerasim Grachevik, migratory birds are expected in Russia. Making long-distance flights, they return from warm countries. How do they navigate? Why do they fly like a wedge? What do they eat? We decided to answer these and other “bird” questions.
How to get directions
How not to make a mistake with the route? After all, a mistake will cost your life! But for winged travelers this is not a problem at all: the routes have long been determined and remain unchanged from year to year. The younger generation learns where to head from their older comrades. But what if there is only one inexperienced youngster left in the flock? How to find out the road without a map and GPS navigator? It turns out that every bird has such a navigator; it is an innate instinct that leads birds in the right direction. This is confirmed by cases when young individuals made their first flight completely independently.
Wind, wind, you are powerful!
Weather conditions certainly influence the course of migration. In warm weather, birds fly longer and the flow of arriving birds increases dramatically. And if suddenly there is a strong cold snap, the birds may even turn back to the south. During the autumn migration, colder temperatures promote faster departure. Ducks can move south without stopping, covering long distances - 150-200 km. The wind can interfere with the flight, and, on the contrary, facilitate it. Seagulls, flying rather slowly, fly in a calm or with a tailwind. Naturally, with such an assistant, the flight is more intense.
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Pay in order!
Many birds fly in a wedge formation, such as cranes and geese. Some believe that birds fly in a wedge in order to cut through the air, just as the bow of a ship cuts through the waves. But that's not true. The meaning of the wedge-shaped formation, however, like any other (line, arc, oblique line), is to prevent birds from getting caught in the vortex-like air currents created by the movements of the wings of their neighbors. Due to the fact that the birds flying in front flapping their wings, additional lift is created for those flying behind. Geese save up to 20% energy in this way. At the same time, the bird flying in front has a great responsibility: it is a conductor and guide for the entire flock. This is hard work: the senses and nervous system are in constant tension. Therefore, the leading bird gets tired faster and is soon replaced by another.
The flight is a flight, and lunch is on schedule!
During the flight, the flock will not always be able to eat fully - the opportunities for obtaining food are very limited. Where do you get the strength for such hard work? When going on a long journey, we usually think about our nutrition in advance. So the birds prefer to eat well on the way: in preparation for the flight, they eat very heavily in order to accumulate more fat reserves for the long flight.
I have time to rest, but the flight takes an hour
Flight is a difficult task, and energy reserves quickly deplete, so it is very important for birds to recuperate. Some species of birds fly practically without rest: woodcock, for example, covers a distance of up to 500 km without stopping in one night
Others cannot boast of such endurance and make many stops. As a rule, the speed of these birds is low. They arrange a rest near ponds, where they can recuperate, refresh themselves and quench their thirst. This takes a lot of time, and the flight takes about an hour on average per day.
Wandering in the dark
Our travelers already have a lot of problems, and then there are the hunters! The flocking lifestyle helps the birds. This way you have a better chance of noticing an attacking enemy. Packmates always signal each other about danger. It is no secret for hunters that it is much easier to get close to a single bird than to get close to a group. However, detecting a flock during a flight is not so easy. Birds fly at a much higher altitude than usual, while still managing to breathe thin, frosty air.
Text: Nadezhda Timokhova
Infographics: Maria Zaitseva
Flight
Since during the flight birds are not always able to find normal food for themselves, before setting off, they begin to gain weight intensively: therefore, if birds migrate over medium distances, they increase their weight by 15-25%, those that fly very far, they recover by fifty and even one hundred percent.
Before setting off, the birds gather in flocks and fly away from their homes, mainly on clear moonlit nights. It is interesting that there are birds that fly only at night (woodcocks, quails), and others that are able to continue their journey regardless of the time of day (geese, ducks, loons).
Birds prefer to fly mainly in a wedge: this gives them the opportunity to avoid vortex-like flows of air masses that arise due to the movements of the wings of birds located on the side. Thanks to the air currents arising from the movement of the wings of birds flying in front, additional lift is created for those flying behind, which allows birds to save about twenty percent of energy.
The birds flying in front are the strongest members of the flock, and the first bird also has a huge responsibility: being a guide, all its senses and nervous system are constantly tense. Naturally, she cannot remain in this state for long, and when she begins to show the first signs of fatigue, she is immediately replaced by another.
Birds fly quite quickly: small individuals are able to cover distances at a speed of about 30 km/h, large ones - about 80 km/h, some species can even accelerate to three hundred kilometers.
Birds prefer to move at an altitude of one to one and a half kilometers above sea level. This gives them the opportunity to fly at higher speeds than usual: at this altitude the air is very thin and has less resistance. But in some cases, birds are quite capable of descending to a height of up to one hundred meters, or flying up to thousands of kilometers above sea level (for example, bar-headed geese, on their way to India, fly over the Himalayas, whose height is almost 9 thousand meters).
In warm weather, birds fly much faster and are able to fly about 200 km without stopping. Much in this case depends on the movement of air masses: they can either interfere with the flight of birds or facilitate them (when moving with a tailwind, the flock moves faster).
Seasonal migrations of birds over long distances consist of several stages, between which they make rest stops. Some birds fly almost non-stop; for example, a woodcock is quite capable of flying about 500 kilometers in one night.
But the smaller the birds, the more often they stop, making rest near water bodies, while they take a lot of time to rest, and therefore they spend only a little more than an hour a day on the flight. If necessary (for example, crossing a sea or ocean), they are quite capable of continuously flying from 70 to 90 hours, covering a distance of 4 thousand km.
Annual cycle of birds
The life of birds, as well as other animals, on most of our planet is subject to changing seasons. The only exceptions are those areas where tropical forests are located.
The annual cycle of birds consists of four main stages. The first of these is the breeding season. Then comes molting, the seasonal migration of birds. The last stage is wintering.
As for seasonal migrations, they are not a continuous period for birds. There are flights in spring and autumn. At the same time, they are separated from each other by the wintering stage. The spring migration of birds can be considered as a phenomenon that is partially associated with preparation for the breeding stage. Autumn migrations are a search for food to preserve the species.
Some myths
Now we are so smart, we know everything, we are aware of everything. And if we don’t know something, we can easily find the answer to the question in electronic encyclopedias and printed reference books. But two thousand years ago our ancestors did not have such an option. Everything that our ancestors did not know and did not understand, they explained by the influence of forces from above. Where do you think the roots of the pagans come from? It is precisely from here - from a lack of understanding of the processes that took place around a person.
Ornithology, the science of birds, today can tell you dozens of myths that are associated with the seasonal migration of birds. We don’t have that much time, so we’ll talk about a few—the main ones. Aristotle, for example, trying to find an answer to the question of where birds go for the winter, quite sincerely believed that some birds, like bears, hibernate, while the other part is completely transformed into a different species. For example, Aristotle was sure that with the arrival of cold weather, the redstart turns into the morning dawn. You may ask where he got this from. And the answer will be very simple: the scientist and philosopher saw the redstart exclusively in the summer (in winter it flew to warmer regions for the winter), and the morning dawn only in the winter. This is where this crazy, from today's point of view, idea was born.
The most interesting thing is that despite the fact that Aristotle lived before the advent of our era, some of his followers, even several centuries ago, still continued to adhere to his views. Some of them believed that swallows hibernate in the mud. They say that, like swifts, they sink to the bottom of the reservoir and, wrapped in silt, fall asleep until the weather warms up. Some dreamers were convinced that a bird, in principle, was not capable of covering the distance from one continent to another, and assumed that the birds were waiting out the cold... on the Moon! Another part was convinced that large birds are more resilient, and small ones are too fragile for long and grueling journeys, so large representatives of birds carry smaller brothers on their backs. Just as the goose in the fairy tale transported Nils, and the swallow transported Thumbelina.
Interesting birds that live and are found in Russia
Russia is famous for its diversity of flora and fauna
The territory of the country is inhabited by a large number of birds, which attract the attention of both indigenous residents and tourists.
Capercaillie
While singing, the bird loses its hearing, which is why it was called that. Males are not only brighter in color, but also have more females. The capercaillie flies heavily and with a lot of noise, which is why it leads a mostly sedentary lifestyle. The largest representative of the grouse order, nests on the ground. Wood grouse are herbivores, but the chicks are fed insects and spiders. In captivity and in freedom, this species can produce joint offspring with black grouse, which are called mezhnyak.
Crow
Numerous experiments have proven that the raven is the smartest bird and is capable of reasoning at the level of analogies. Birds can express various emotions, empathize, imitate sounds, distinguish and remember faces. Having discovered the body of a relative, the crows cry out heart-rending sounds for some time, and then freeze on the branches with a sad look. Crows love to have fun: they slide off snow-covered roofs and play with tennis balls
This is how birds attract the attention of their fellow birds
Starling
Starlings arrive in Russia in early spring. They can burst into trills, taking short breaks. They also imitate the sounds of other birds and animals. The most experienced warblers have up to 40 alternating sounds in their repertoire. Even in the nests, parents begin to teach the chicks the art of singing. During the mating season, the starling's nose changes color from black to yellow. The bird's flight speed reaches 50 km/h.
Common nightjar
The nightjar actually eats parasitic insects on cows, sheep or goats. The inconspicuous bird is known for its extraordinary singing. The male periodically changes the volume, pitch and frequency of the trill, which can be heard 600 m away.
The elongated body, like that of a cuckoo, does not exceed 28 cm, and the nightjar weighs no more than 100 grams. In the air, these birds can be confused with a swift or a falcon, since their flight is energetic and maneuverable, but at the same time silent.
Flamingo
There are 6 species in the flamingodae family in the world. The largest and most common is pink, reaching 130 cm in height. The bright color of the plumage is given by lipochromes that come with food. To reduce heat loss in the wind, flamingos alternately hide their legs in their plumage.
Birds live on the banks of small bodies of water in colonies of up to hundreds of thousands of individuals. The thick skin on the legs allows you to stay near salty and alkaline bodies of water. Birds can tolerate high temperature changes. Flamingos do not nest in Russia, but the bird has been repeatedly spotted migrating near water bodies.
Tkachik
Granivorous birds are of medium size - body length does not exceed 17 cm. Outwardly they resemble sparrows, although the color of the feathers is individual for each species. All weavers live in flocks, and in some colonies there are up to 10,000 individuals.
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A distinctive feature is the ability to weave closed nests. They are built as close to the neighbor as possible. Nests come in different shapes: from a small basket to collective settlements buried in the crown of a tree.
Hoopoe
A small bird up to 30 cm is distinguished by a crest of red feathers. The hoopoe's flight is low and maneuverable, but it is capable of rising to great heights. Unlike most birds, this species never removes droppings from the nest. During the incubation of chicks, the birds produce an oily liquid with an unpleasant, pungent odor. By shooting it, along with its droppings, at a predator, the hoopoe protects its offspring.
Mandarin duck
A small waterfowl duck, reaching only 25 cm in length, is distinguished by its bright color. The mandarin duck builds its nests in hollows at a height of up to 15 m. The male has a crest and is brighter in color than the female. This species does not interbreed with other ducks because it has a smaller number of chromosomes. Mandarin ducks are able to rise vertically into the air from water or from land. In Russia, the bird is listed in the Red Book. Local residents breed it in parks.
Nightingale
It is considered the largest of the songbirds. The nightingale reaches a length of 17 cm and weighs about 25 grams. Migratory birds winter in northern Africa and return to their native lands in late spring. Children and adults enjoy listening to the singing of nightingales. The bird is diverse in species, each of which has a distinctive color. Birds live in different parts of the planet.
The ability of pigeons to find their way home
The amazing ability of pigeons to find their way to home has been known since time immemorial. The armies of the ancient Persians, Assyrians, Egyptians and Phoenicians sent messages from their campaigns with pigeons. During both world wars, pigeon mail performed such a service that monuments were erected in honor of the feathered letter carriers in Brussels and the French city of Lyon. At competitions, carrier pigeons are transported 150-1000 kilometers and released. The time the birds return to the dovecote is recorded using special devices. Well-trained pigeons fly home at an average speed of 80 kilometers per hour, the best of them are able to cover 1000 kilometers in a day.
The third monument to pigeons has not yet been built, but it has long been deserved by them thanks to their outstanding contribution to the study of the methods of orientation of birds. It turned out, for example, that pigeons can return to the dovecote from afar despite severe “myopia.” The birds were made “myopic” for the duration of the experiment by putting frosted contact lenses on their eyes, which made it possible to distinguish only the contours of nearby objects. And with such lenses, pigeons were released 130 km from the dovecote. Half-blind birds soared up and rushed home at great heights, seeing nothing around them except an impenetrable gray fog. Almost everyone managed to get to the place safely, although “myopia” did not allow them to find the dovecote itself. The pigeons landed within a radius of 200 meters from her and patiently waited to get rid of the annoying lenses.
Bird life in summer
The main task of each species of birds for the summer is feeding and adapting the chicks to life. If the summer turns out to be rainy and cool, then the life of birds becomes somewhat more difficult. Chicks die from colds and hunger. And the parents themselves are in great danger while it rains.
Drought is also not a favorable state of nature for birds. For birds living in swamps, drought is a disaster. During such periods, wading birds are forced to go out in search of a new habitat. And if the hot days drag on, the vegetation begins to dry out. This situation is dangerous for all types of birds.
The main task of birds for the summer is to teach their chicks to fly, so that in the fall they can fly south with their parents.
As a rule, summer days are accompanied by early dawn and late sunset, so the days of many birds become longer. So, for example, chickadees, they wake up with the first rays of the sun and fall asleep at sunset.
And the songs of the redstart can be heard at any time of the day, because they wake up before sunrise and fall asleep at dusk.
In the summer, birds are especially active and lead their usual lifestyle. Day and night predators hunt in forests and steppes. The familiar inhabitants of crowded places fly along the streets of cities and villages.
Bird groups and migration
Based on the nature of seasonal migrations, three groups of birds are distinguished: migratory (swallows, starlings, swans), nomadic (siskins, bullfinches, woodpeckers) and sedentary (ravens, tits, sparrows). The former carry out long flights for wintering along certain routes, then returning to their former nesting sites. The latter roam in nearby areas, their movements do not have constant directions. The third group lives sedentary in one area for a whole year. It should also be noted that birds of the same species may be migratory in some parts of their range, but nomadic or sedentary in others.
According to reports from ornithologists, the winter life of birds is still rather poorly studied. When flying to wintering sites, they adhere to certain routes that do not change for a long time. The flight paths of some species may be shared over some distance. Birds tend to fly along the path that is closest in nature to their native habitat and where food familiar to them can be found.
It happens that the autumn departure of birds lasts for several weeks, but the return flight to their native lands takes several days. Upon returning home, birds always run the risk of encountering unfavorable circumstances, for example, bad weather or unmelted snow. And if the arrival occurs annually at the same time, then the snow melts at different times every year. This discrepancy causes the death of returning birds.
What wintering sites do birds choose?
As a rule, birds settle where the habitat is similar to that in which they live in their homeland. If birds choose forests for their nesting, then these are the areas they will look for in areas with a warm climate. Birds living in steppes, meadows or fields will look for familiar conditions for settlement. This will allow you to find their usual food. Thus, the birds fly away to those regions where living conditions differ little from what they are used to.
They find their way to wintering places thanks to a superbly developed navigation system. For some birds, major landmarks are mountains, sea coasts, and so on. There are species that calmly cross the water surfaces of the ocean that are not very diverse.
Those bird species that fly during the day, those birds that travel in the dark, rely only on their own navigation system.
The winter cold will recede, and the birds that have flown to warmer climes will return home again. They will announce the arrival of spring with cheerful trills and will prepare for the next stage of their lives.
Now you know to which warm regions birds fly. Good luck in your further study of birds!
There are some mysteries behind the seasonal migrations of birds, for example, how do they determine the start time of the migration, and how do they manage to find their native nest with such accuracy? You can learn about this and what pushes birds to change places in this article.
Unexplained migrations; What are the names of birds that never make seasonal flights?
It is not clear why some bird species, despite the same weather conditions, suddenly want to migrate. For example, these are hazel grouse and black grouse, which are considered sedentary birds; moreover, they fly poorly: suddenly in winter, for no reason, some of them, even if for a short distance, move from their main place of residence.
And there are birds that never fly away at all, live next to people constantly and are completely dependent on them for survival. These are synanthropes: rock pigeon, city sparrow, jackdaw, for example.
No matter how harsh and snowy the winter is, they will never migrate, and often die in large numbers because of this. Such birds should not be confused with sedentary birds that live in the wild and never fly to another area for the winter. Watch a video about bird migration.
Migration is a delicate matter
As it turned out from the results of ringing, in the south of Western Siberia, summer-autumn migrations in some species begin 20-30 days after the end of spring ones. What is the reason for such a long, essentially permanent migration? A detailed study of the migration of waders in the forest-steppe of Western Siberia showed that age-sex differences in migratory behavior play a major role in this.
The summer-autumn migration of all species of waders begins with adults, and ends with young ones. As a rule, adult birds nesting north of the forest-steppe arrive 12-30 days before the first-year birds appear; for those nesting in the forest-tundra and tundra, this difference is already 20-40 days. Then the share of adult waders in the migrant flow decreases, amounting to no more than 20% by the end of August.
Siberian ornithologists have ringed a total of about 150 thousand individuals and received about 1.5 thousand reports of finds of “their” tagged birds and about 2.5 thousand reports of birds ringed in other places
This separation in time and space of different age groups, leading to their relative isolation during the migration period, is aimed at reducing intra- and interspecific competition in the post-breeding period. This is important for maintaining good physical “shape” of individuals, since special studies have shown that at the main stopovers of waders, their food resources can be depleted quite quickly.
At different times, individuals of different sexes migrate among waders.
So, in some groups of waders the males fly first, in others the females fly first. The flight sequence of adult birds is determined by the degree of their participation in incubating and guiding the chicks. For example, among the Turukhtan males do not take part in raising offspring, and it is they who make up about 90% of all migrants until mid-July, but in August it is mainly females that fly. In the round-nosed phalarope,
on the contrary, from early to mid-July only females fly, then until July 25 - females and males, and later - only males. This is due to the fact that the females of this species do not even take part in incubating the eggs. Males or female waders that leave a nest or brood for a partner usually do not linger in the nesting areas, but immediately begin directed movements towards the wintering areas.
Other factors may also influence the onset of flight. For example, it was discovered that during a stop in the lake area. Young females of some waders accumulate fat reserves faster than males. Apparently, due to this, the average duration of their stay in places of aggregation is less than that of males, the proportion of which naturally increases towards the end of the migration period.
Differences in the timing of migration of different age and sex groups probably contribute to a more even distribution of the population of shorebirds, avoiding high densities and, accordingly, severe competition for resources, inevitable during the simultaneous migration of birds.
Migratory Klondike
About 450 species of birds live in the south of Western Siberia, and almost 90% of them make regular movements twice a year: in the fall from their nesting sites to wintering grounds, and in the spring in the opposite direction. For some species - short-term migrants - the length of the routes is insignificant and amounts to only hundreds of kilometers, but for the majority it reaches several thousand.
The first work on ringing birds (mainly ducks) in our region was carried out in 1949-51. employees of the Institute of Systematics and Ecology of Animals SB RAS (then Biological). In the early 1970s, the Institute began systematic research into migratory birds of Western Siberia, mainly in the area of the Barabinskaya forest-steppe adjacent to Lake. Chany and is a real “paradise” for waterfowl and semi-aquatic birds. This choice was due to the fact that the forest-steppe of Western Siberia is both a huge “incubator” in which hundreds of thousands of chicks are hatched during the nesting period, and a vast “station” where an even larger number of birds nesting in the taiga and forest-tundra stop during migration.
The special significance of the forest-steppe and steppe of Western Siberia for waterbirds is determined by the richness of its wetlands. The biological productivity of these mostly shallow water bodies is several times higher than that of lakes located further north in the taiga. That is why in spring and autumn, many migratory birds, before making their move further, stay in the forest-steppe for 10-20 days to replenish their fat reserves.
Some species have to travel vast distances to reach areas rich in protein food and shelter, which they need to carry out another important bird “business” - molting. Most bird species change plumage every year. Ducks, for example, completely lose their ability to fly during molting, which creates special problems for them. The results of banding showed that ducks molt on the reservoirs of Baraba, nesting at a distance of up to 2-3 thousand km!
Contrary to the generally accepted opinion, according to which in spring birds migrate from south to north, and in autumn, on the contrary, some birds migrate in a longitudinal direction. For example, lapwing, one of the widespread species of waders that nests in the south of Siberia, spends the winter in the countries of Western Europe - France, Belgium, Holland and Italy. Some species of our ducks also winter in Europe - Shoveler, Wigeon, Whistling Teal, Gadling Teal, Red-headed Pochard (they, by the way, are one of the most likely spreaders of “bird flu”).
