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Seasonal bird migrations
1. How did the birds fly?
There is hardly another question related to the migrations of birds, to which so different answers are given. The reason for this is the absence of irrefutable facts. Some of the many theories on the occurrence of flights that exist are considered generally acceptable. According to Thomson (1926), they can now be reduced to three hypotheses:
1. The homeland of migratory birds was their modern nesting area. The onset of the glacier forced the birds to retreat south. Every summer they returned (as far as was possible) to the north for breeding chicks and became migratory birds.
2. The homeland of migratory birds was the modern nesting area. Driven back by the glacier to the south, the birds settled a small territory and turned into sedentary birds. But the need to return to his homeland remained in heredity. Therefore, at the end of the ice age, they developed flights.
3. The homeland of migratory birds was the modern wintering area and other southern areas. Mass reproduction in these areas forced the birds to settle in the area freed from the ice.
According to these hypotheses, the cause of migratory birds is the influence of the ice age. This eliminates the possibility of the existence of flights to the Ice Age, as Eckardt allowed. Flights in the uniform warm climate of the Tertiary period probably resembled the movement of our modern nomadic birds. Further deterioration of the conditions of existence at the beginning of the ice age forced the birds to expand their migrations more and more as the northern winters became longer and more severe. Accordingly, the terms of the summer stay of birds in the homeland were shortened. When the northern continents were largely covered by glaciation, these flights completely stopped. After the retreat of the ice, the birds again settled the vacated area and so gradually penetrated into the nests of their ancient homeland. But every year they were forced to leave it for the climatically unfavorable time of the year and seek refuge in the areas to which they retreated during the ice age. These bird retreats repeated over millennia in the fall and annual new or, more precisely, repeated colonization of the abandoned areas in spring as a result of seasonal climatic conditions due to the onset of the glacier are now considered the main cause of bird migrations, if you can talk about a common opinion in such a question. In this regard, we adhere to the views of Myra and Meize (1930), to whom we owe the latest development of this problem. Although their evidence is generally clear, many details are still dubious. So, for example, why is the behavior of sedentary and nomadic birds in Germany in many ways different from migratory birds? Did sedentary and wandering birds move only after the ice age? Why do so many bird species fly far beyond the influence of the ice age? And finally, all the hypotheses about the significance of the ice age in the occurrence of bird migration do not take into account the possible influence of the last interglacial period, when, at least in Europe, almost tertiary climatic conditions were established for several thousand years. As a result, subtropical plants and animals could penetrate deep into Central Europe. Has this “Hazelnut time” (Haselgipfel) from which we have been separated for about 8,000 years, did not have a more lasting effect on the birds ’attitude to their habitat than the last glaciation, which was 23,000 years ago? Further, if during millennia the seasonal periodicity of climatic phenomena led, eventually, to the emergence of bird migrations, and this acquired habit even became inherited, so that now flights are made largely regardless of the influence of the external environment, then explain the loss of this habit during such a short time as several years or even decades when migratory birds become sedentary again?
These are some of those objections and doubts that can be put forward against the accepted hypotheses about the origin of migrations of birds. This does not facilitate the resolution of the issue, but it should not scare away those who want to study its development in more detail. We deliberately point out here these difficulties in order to encourage a critical attitude to the theoretical part of the whole problem, since well-founded hypotheses can contribute to its development, and guesses not supported by scientific data will only harm it.
2. Bird migration kato the subject of scientific research
In 1757, Linnaeus published a work on bird migrations, in which he recommended organizing permanent observation points. Systematic research began in the middle of the XIX century. They were based on observations of the flight of birds in space and time. Gradually, the research methodology was being improved more and more, but great success in the study of migratory birds was achieved only at the beginning of the 20th century thanks to the spread of ringing. Now radars are also used, observations in a vertically directed telescope (this method was first used in 1965), night visual observations of illuminated greenhouses, observations in a telescope against the disk of the moon (first used in America in 1951, Lowery), voices passing by birds and the most expensive, but also the most effective method - radio beacons. The only negative is that each beacon weighs 3-5 grams, which allows you to watch only large birds.
Currently, the study of bird migrations has become a methodically sound scientific area that includes information not only on the timing and migration of birds, but also on population dynamics, mortality, puberty, life expectancy, mating behavior, physiology, molting, orientation, reactions to weather , geographic distribution and much more.
The first who seriously engaged in systematic observations of the migrations of birds was a German scientist G. Getke, who settled in 1837 on the island of Helgoland in the North Sea. Here for thousands of years, the birds regularly stayed on the rest during the flights. Getk began to study which birds make flights through Helgoland, which of them migrate during the day, which at night. A station for the study of bird migration was established on the island, which is still in effect (now it is a branch of the station in Wilhelmshaven, Germany). Approximately in the same years, when Getke worked for Helgoland, the Russian scientist A.F. Middendorf organized a network of ornithological observations throughout the European part of Russia, i.e. in most of Europe. As a result, very valuable information was obtained. First of all, it turned out that in spring the flight of birds to the north takes place on a broad front across the vast territory of Russia, and each species maintains its arrival time.
A new era in the study of birds began from the time when the Dane H. Mortenser in 1899 began to mark birds, attaching light metal rings with a bird’s serial number and address to his feet. After 13 years, this method has already been applied worldwide. The best results are achieved when tagging young and adult individuals of the same species in different habitats: in nesting areas, resting on the flight, wintering.
3. Forms of seasonal migrations
Despite the enormous consumption of Eneogria and numerous dangers, seasonal migrations seem to be still useful for birds.
Among the seasonal migrations of birds occurring throughout the year, the following forms can be called: post-nesting migrations, autumn-winter migrations, autumn migration, spring migration. From the second half of the summer, the post-nest migrations begin, peculiar to both migrating and migratory birds. Post-nesting migrations are accompanied by the formation of clusters and flocks that are of great importance in the life of birds during the non-nesting period and, especially, during migrations. In the fall, post-nesting migrations pass from migratory birds to autumn-winter migrations, and from migratory ones, to migratory birds to autumn migrations. The non-nesting period ends with a spring migration of birds from wintering to their nesting regions. Let us dwell on the characteristics of individual forms.
Post nesting migrations. In the nesting period, each pair is strictly tied to the nesting site. While the chicks are brooding and feeding, the birds are sedentary, collecting food in the vicinity of the nest. At the end of breeding, sedentaryness in birds is disturbed, the brood leaves the breeding area and proceeds to post-nesting movements and migrations to more distant places from the nest.
Post-nesting migrations are characteristic of both migratory and migratory species. In time, they coincide with noticeable changes in feeding conditions, due to which the brood can no longer satisfy its increased food needs within a small nesting (feeding) area. Changes in the feeding conditions of birds are influenced by several reasons: seasonal changes in the environment, the transfer of birds to new types of feed, reduction of stocks in the nesting area as a result of the long-term feeding activity of the brood.
Seasonal changes in the environment appear in the second half of summer and are expressed in some reduction in the length of the day, a decrease in the intensity of illumination, and a decrease in air temperature, especially at night. These changes cause changes in the life of animals and in the life of plants that birds feed on. Part of the plants to this period (or during it) finish their flowering, growth and even vegetation, as a result of which dried flowers, coarse leaves and stems lose their feeding value. But along with this, many plants produce seeds and berries, representing a new type of seasonal bird food.
During this period, some insects and other invertebrates complete their development cycle and, laying their eggs, die (a number of species of butterflies, beetles). Some invertebrates under the influence of night cold take refuge in shelters and become less active. Some insects move from shaded places to other, more temperature-friendly and more favorable places. Finally, many insects in this period appear the second and third generations, and their numbers increase significantly. As a result of the presence of these factors, not only the qualitative and quantitative composition of bird feeds changes, but also, which is important to emphasize, their spatial distribution.
These changes affect the geographical distribution of birds. After the departure of the chicks, for example, most species of forest birds change their biotopes and move to other, more clarified places. Inside the forest, birds are concentrated mainly in areas of light forest. Deaf, shaded areas, especially with moist soils, where a significant revival was observed in the spring during the nesting period, become deserted and almost never visited by birds. The usual distribution of birds for the nesting period is noticeably disturbed. From one place the birds disappear, in others - their concentration increases sharply. Illuminated forest edges, clearings, light forest areas that are well warmed by the sun’s rays, where insects are still numerous and active and where vegetable food is found in the form of ripened fruits and seeds of grassy plants, become the most lively. Insectivorous as well as granivorous birds, whose flight chicks still need animal feed, move to these places.
Reported changes in nutritional conditions become especially noticeable in the middle zone of European Russia at the end of July and August; it was at this time that the majority of birds in the post-nesting migrations are pronounced.
The transition to new types of food is an important factor affecting the emergence of post-nesting bird migrations. It is closely dependent on seasonal changes in food supply. For example, the full or partial transition of many birds in the post-nesting period from animal feed to vegetable is widely known. Repeating year after year, the change in diet has become physiological need the birds. There are also age-related changes in the composition of food. Eating in the nest of animal food, the chicks of many birds, after their departure from the nest, begin to use vegetable food.
The feeding activity of birds, which takes place over a long period of reproduction within a limited individual breeding area, leads to a reduction in the food supply in its territory. According to some data, the number, for example, of caterpillars and pupae of some insects (bird feeding objects) sometimes decreases by 40–62% and even by 72% (Korol'kova, 1957). As a result, in places of feeding, individual components of the diet may be scarce, while the number of others will be sufficient. In this case, despite the significant total food reserves, the brood will not be able to feed on its nesting site and therefore moves beyond it.
All of the above gives grounds to believe that the leading factor in post-nesting migrations in birds is the food factor. Under his influence, the birds leave the nesting site in search of food and begin to wander in the immediate and later distant surroundings. The adaptive significance of post-nesting migrations consists in the redistribution of the population of the population over the territory in connection with the upcoming changes in feeding conditions.
Autumn-winter migrations. Weak post-nesting environmental changes are gradually turning into sharper autumn-winter changes that have a deep and many-sided effect on the life of birds. These changes, as noted earlier, lead to a significant deterioration in many birds, feeding conditions, thermoregulation and protective conditions. Small movements in the near and far environs of the nesting places of wandering birds are transformed into more distant migrations that flow from them throughout the autumn and winter.
The basis of the autumn-winter movements of nomadic birds is also a feeding factor, as evidenced by many data. It is well known that when crop failure occurs, the range of bird movement increases, and in such years even semi-seated birds (black grouse, forest ptarmigan, etc.) undertake long-distance migrations, appearing in places where they are not in normal years. The feeding factor is the main cause of the so-called invasions in birds. It is known that such nomadic species, such as the waxwing, crossbill, walnut, shchur, etc., in the years of crop failure, undertake unusually mass and long-range migrations, evicting sometimes far beyond their nesting area.
The dependence of migrations on forage conditions is particularly clearly revealed when analyzing the nature of bird movements. During the search for food, these birds move from one place to another, lingering on each of them as much time as they need to eat the food they find. In species with sufficient stocks of feed, continuous movements alternate with a more or less long delay in feeding places. Such a character of migrations is common mainly for birds feeding on vegetable fodder in these seasons (woodpeckers, crossbills, sisy, tapas and others). Certain species of birds, whose food is less abundant and dispersed, wander continuously. This is mainly characteristic of insectivorous (tits, blood orange) and other zoophagous birds.
Food conditions determine the range of autumn-winter migrations. It is different not only in different species, but also in populations. This is well known, for example, in relation to big tits. According to the ringing in the European part of the former USSR, the majority of adults and some young birds in the autumn-winter period are limited to small migrations to the nesting areas, during which they move away from the nesting places for several tens of kilometers, settling most often in settlements. A part of adults and the majority of young birds move away from a nesting area at a distance from several tens to hundreds of kilometers. Finally, a small number of adults and 25–30% of young birds migrate a distance of from one hundred to two thousand kilometers (Likhachev, 1957; Mikheev, 1953).
Near migrations take place in populations and individuals living in the autumn-winter period in sufficiently biotopes. In the presence of poor biotopes of food, birds undertake more distant movements. Young birds are wandering more and more than old ones. By spring, nomadic birds return to their nesting areas.
Autumn and spring flights. Migratory birds are less adapted or not at all adapted to the changes in living conditions that come in the autumn-winter period. Therefore, they fly away from their breeding sites and overwhelmingly hibernate in warmer climatic zones than nomads.
Among migratory birds there are species, part of the populations of which remain to winter in the nesting area or at least in such regions of northern and temperate latitudes, from where another part of the populations of this species flies away. Such species with partial departure can be called weakly migratory, in contrast to real migratory, in which all populations make flights without exception. To imagine the nature and causes of migrations of this group of birds, consider some examples.
The white partridges inhabiting the arctic islands for the most part are migratory, as they fly to the mainland for the winter to the forest tundra for the winter. But some, apparently adult birds, remain to winter on the islands, feeding at this time on the slopes bare from snow or on snow pits dug up by reindeer. Consequently, with food, white partridges can tolerate the harsh conditions of winter.
Partial departure is observed in gray crows. As shown by the banding in Latvia, all populations of young and a significant part of adult crows fly to spend the winter on the Baltic coast at a distance of 900-1000 km from their nesting sites, and only one fourth of the adult bird population hibernates on the spot. These include the most adapted individuals who find themselves in favorable feeding conditions. It is also known that for the winter the northern populations of crows arrive in the southern habitat area, and the southern ones fly further still to the south. This suggests that if the northern population can feed on the southern habitat, the reason for the flight of the latter depends not on forage, but on some other conditions. But we must not forget that northern populations are better adapted to adverse environmental conditions and, in particular, to low temperatures than southern ones. In addition, when flying to more southerly regions, the northern crow populations find themselves in longer daylight conditions and at a favorable temperature. Because of this, they can live through the winter on that food base, where local populations that migrate to the south are not able to feed themselves.
A vivid example of the dependence of the autumn departure of weakly migratory birds on feeding conditions is the field thrush. In normal years, the thrush-fieldfare flies away from the central regions in mid-October, but during the rowan harvest, some birds linger until December and January, and some flocks remain for the whole winter, successfully enduring thirty degrees of frost.
Partial migration is observed in a number of birds: the blackbird, whose old individuals live in many places in Western Europe, and the young ones fly away; at the mallard, remaining in places to winter in a small amount at non-freezing reservoirs in the middle and even northern parts of the country; at the sea-dweller, wintering regularly in small quantities in the ice-free coastal waters of the Barents Sea, etc.
The phenomenon of partial wintering of migratory birds is more often observed in southern latitudes than in northern ones. For example, in England, among songbirds, ringed in nesting sites and then caught again, individuals wintering near breeding grounds were: in Scotland - 26%, in the north of England - 43%, in the south of England - 65% (Lac, 1957).
The reason for the partial wintering in this category of migratory birds can be called their ecological features and, in particular, in a lesser compared with nomadic adaptability to winter changes in forage and other living conditions. This can be shown in the following example. Of the 35 species of weakly migratory birds nesting in the former Privolzhsko-Dubnensky Reserve, 32 species (91%) feed on the ground in the summer and only 3 (9%) in the trees. Of the 26 species of nomadic birds of the reserve, only 2 species of birds (8%) produce food on the ground; the remaining 23 species (92%) are in the trees and in the air (Mikheev, 1964). If there is a strong snow cover, weakly migratory birds cannot stay wintering in the reserve due to lack of food and should fly away regardless of whether other living conditions are favorable for them or not. And only with the confluence of certain circumstances, the partial hibernation of birds in these places is rarely possible (for example, in human habitation).
Weakly migratory birds generally react more sensitively to autumn changes in the environment, leave the nesting area earlier and start autumn migrations earlier than nomadic ones. Only a small part of their population is delayed or remains to winter in the nesting area, but the main part flies away to warmer climatic zones.
Thus, the population of weakly migratory bird species is not uniform in severity of seasonal migrations. Some populations are limited to migrations and movements within the cold and temperate zones, while others make regular and more distant flights to warm climatic zones.
In contrast to the group considered above, real migratory birds, which constitute the majority of migrants, never show partial migrations and partial wintering in the breeding area. All of them fly away for the winter to warm climatic zones. This is due to the fact that the overwhelming majority of real migratory birds have become adapted to life only during the warm seasons of the year and cannot tolerate drastic changes Wednesday, coming in the autumn-winter period. Fly to other parts of the range is almost the only adaptation in real migratory birds, which helps them avoid the negative effects of adverse feeding, temperature and other living conditions occurring in the nesting area in winter.
4. Reasons for migration
The flight of birds is influenced by the lack of food, and the shortening of the day in the fall, and changes in air pressure, temperature, and a complex of reflexes, which has not yet been fully studied. The desire of birds to fly is a complex reaction to change in the surrounding natural conditions. Bears and badgers, for example, hide in dens and hibernate for the winter. Fish "fall asleep" in deep pools under the ice. This is a passive reaction to changes in the surrounding world.
And the birds react to them very actively: they fly far, sometimes thousands of kilometers away, to find the natural conditions most suitable for wintering or nesting.
The sharp deterioration of living conditions in the winter boils down mainly to greater or lesser difficulty in getting the necessary and increased amount of food compared to summer. The winter season makes major changes in the feeding conditions of birds of high and moderate latitudes. First of all, with the onset of winter, the total reserves and feed set are sharply reduced. During this harsh time, the green parts of plants, as well as the seeds, berries, and fruits of perennial and annual grasses and low shrubs covered with snow, fall out of their diet. Most insects and invertebrates disappear. Amphibians, reptiles and fish become completely inaccessible for feeding birds. In winter, it is difficult to hunt mouse-like rodents and other small animals, as they hide under deep snow cover or hibernate. Available winter food in these latitudes remain mainly berries, seeds, needles and terminal branches of trees and shrubs, as well as some insects hiding in the trunks and branches of woody plants, their eggs, larvae and pupae, small species of mammals, and, finally, different waste and waste in human settlements, in landfills and on roads.
Adaptations to changes in food conditions, reducing the intensity of seasonal movements and allowing birds to winter in northern and temperate latitudes, are reduced mainly to changing feeds according to the seasons of the year, changing places and ways of searching for food, and storing feeds.
In this regard, in the process of evolution, many birds have developed a seasonal change of feed, that is, the transition to feeding on those feeds that are most abundant or available at any given season of the year. Let us give some examples.
In summer, the Great Spotted Woodpecker feeds mainly on insects, but in the second half of summer it also feeds on plant foods: raspberry berries, carrots, bird cherry trees, much later, cowberry berries and pine or spruce seeds. In autumn or winter, as a rule, it almost completely switches to vegetable food - seeds of coniferous trees, nuts (hazel) and acorns. In early spring, he drinks tree sap, which is of great importance in this most hungry period of the year. Seasonal movements of the woodpecker are reduced to small migrations in high latitudes, where he spends the winter.
The nuthatch in the spring-summer period is fed exclusively by insects and spiders. In the fall and winter, its food ration includes vegetable food - hazelnuts, acorns, seeds of maple, linden, coniferous trees, alder and other tree species. It is the partial herbivorousness that helps this insectivorous bird species to survive the winter in high and temperate latitudes, where they make only small migrations.
For the most part of the year, the black-head tit feeds on various insects, but in winter it also uses vegetable food - seeds of spruce, fir, birch, pine and others, collecting them on snow or pecking out cones. When harvested, these seeds form the basis of nutrition for titanicas for a considerable part of winter, accounting for almost 73% of all food in volume.
In spring and summer, the finch feeds mainly on insects, in early spring, in the second half of summer and in the fall, on seeds of grassy and woody plants that it collects on the ground, which does not allow it to winter in the zone of continuous snow cover. Wintering is located in those areas of temperate latitudes where there is no permanent snow cover.
Most of the species that can change the composition of feed, lead a sedentary and semi-settled way of life or undertake close wanderings and flights within the same high and temperate latitudes.
Use shelters for overnight stays and weather protection. In winter, the lowest temperatures are at night. At nighttime, most birds have a dormant period, during which the feeding stops completely. Consequently, the intensive heat transfer of the body in birds coincides with the period of their least activity and decrease in the level of oxidative processes. This greatly complicates the normal heat exchange with the environment and makes the bird the most vulnerable night cold. In this regard, many birds wintering in cold climatic zones use different kinds of shelter for the night, which weaken the influence of low temperatures and reduce the intensity of heat transfer. In such shelters birds often sit out during the day and in severe frosts and bad weather (blizzards, snowstorms, etc.).
Some species of birds, leading mainly terrestrial mode of life, at night, in cold and bad weather burrow into the snow (for example, black grouse, wood-grouse, hazel grouse, ptarmigan, etc.). The temperature under the snow is not only significantly higher than in the air, but more constant.
In winters, with a small depth of snow cover, birds do not have the opportunity to burrow into the snow and fall into an extremely difficult position. In such winters there is often a massive freezing of black grouse, grouse and other birds that use snow shelters.
5. Classification of birds by the nature of seasonal migrations
By the nature of seasonal migrations, all birds can be divided into four categories: sedentary, invasive, migratory, and migratory, and among migratory there are near and far migrants.
However, it should be immediately noted that many species, populations and even individual individuals can belong not only to one of the mentioned groups. These are the so-called partially migratory species. For example, the Mountain Wagtail (LATIN), which in Western Europe is a sedentary species, in Central - a nearby migrant, in Eastern - a distant migrant. It is possible that with further processing of the ringing results, it will turn out that among the mountain wagtails there are also wandering individuals.
Birds are sedentary birds that live in the same area during the whole year and do not make any regular movements in the area. Some of these birds spend their entire lives within a small nesting area, without going beyond its borders, even in winter. Such birds can be called strictly sedentary. In the northern and temperate latitudes, there are extremely few of them and all of them are almost exclusively synanthropic, i.e. live constantly near human settlements. To the synanthropic species include the house sparrow, gray pigeon, and in some places the field sparrow, the daw, and some other birds. Near a man’s dwelling, they find enough food throughout the year.
After breeding, other members of this category of birds look for food and other favorable conditions outside the nesting area and spend the winter in its immediate vicinity. At the same time, such species of birds do not make continuous migrations, but live all winter more or less settled, in one or several points. These birds can be called semi-settled. They include hazel grouse, wood-grouse, black grouse, part of the population of magpies, common oatmeal, ravens, and others. The semi-habitat is characteristic of birds well supplied with winter feeds.
The category of nomadic birds is made up of birds, which, after breeding, leave the nesting area and make continuous movements until spring, moving away to tens, hundreds, and even thousands of kilometers. In contrast to the sedentary, nomadic people are characterized by constant movement in search of food and the absence of more or less long-term settlement during the winter. If birds linger in places where food is concentrated, it is not for long, as their natural food reserves in winter are not as abundant and stable as in sedentary birds. The direction of movement of wandering birds is variable. Visiting during the wanderings favorable in terms of food and other conditions of the place, birds can repeatedly change the path of their movement in a variety of ways, but more often in the direction of warm climatic zones. This trend is especially noticeable in birds migrating over long distances (hundreds and thousands of kilometers). No wandering birds have any fixed winterings, they are the whole area of winter migrations, which, as a rule, does not go beyond the limits of temperate latitudes.
To the wandering birds include tits, nuthatch, jay, crossbill, shchur, siskin, bullfinch, waxwing, etc.
Invasive species are those that are usually sedentary or wandering, but can sometimes make massive seasonal migrations in different directions and at the same time remain in areas of new settlement for more or less long periods. Sometimes such invasions can spread to very large areas, for example, in most of Western Europe. Typical invasive species in Europe are nutcracker (LATIN), waxwing (LATIN), and many crossbreeds.
The migratory category includes those birds that, after breeding, leave the breeding area and winter migrate to other, relatively remote areas, which lie both within the breeding area of the species and far beyond its borders. In contrast to migrating birds, migratory birds are characterized not only by certain directions and dates of flight, but also by a clearly defined wintering area in which birds live more or less sedentary, or they make minor migrations in search of food. Movement to hibernation in such species takes place not in the form of migrations, but in the form of a well-marked flight. The flight directions of different species and populations may be different, but among the inhabitants of the northern hemisphere most often towards the southern points. Wintering is usually several hundred and even thousands of kilometers away from bird nesting sites and lies in noticeably warmer climatic zones.
The migratory species include most birds of our country: thrushes, ducks, geese, chaffinch, field larks, sandpipers, herons, warblers, warblers, and many others. In winter, all these birds cannot find their usual forage in their summer habitats.
A number of species can be distinguished among birds, with a gradual transition from sedentary to real migratory, migrating over many thousands of kilometers. This diversity of nature of seasonal migrations is explained by the different adaptation of birds to seasonal changes in living conditions.
This classification of seasonal migrations of birds is conditional and is sketchy. At the same time, the migration unit should be taken not as a species as a whole, but as a population of a species, since in many species, some populations are sedentary, others are wandering, and some are migratory.
6. Migrations of birds in time and space
Migrations of birds reveal almost infinite variability in time and space, with each species exhibiting individual migration features. There is a generally accepted view that in spring and autumn birds fly between their summer and winter habitats and that these migrations generally occur from south to north or in the opposite direction. The basis of any forms of seasonal movements of birds is their response to seasonal fluctuations in the environment, and these forms should be considered as qualitatively different stages of a single phenomenon of seasonal migrations. This view holds true for migratory movements of migratory birds, primarily in North America. However, for example, movement from southwest to northeast is characteristic of migratory birds of Europe. In general, migrations to the Northern Hemisphere occur in all directions.
Birds migrate not only in spring and autumn; in fact, flights take place all year round. But spring and autumn - are pronounced and stretch more than 4 months. Spring flights in Europe take place from February to June, and autumn flights from July to November. Each species has its own inherited migratory behavior, including such important indicators as the direction and timing of flights. Regardless of the time of day, they follow from year to year specific models in time and space. Some species fly in a narrow front, some broad, land, as a rule, fly over land, the sea - along the coasts. Most birds do not feed on the road, but there are those who feed during the flight.
In many species of birds, young individuals fly in other ways than adults, thereby increasing the area of distribution.
Many species of birds that fly during the day react in a certain way to the landscape features of the territories over which they move. The margins of deserts, lakes, forests, the foot of mountain ranges and the shores of the seas can have a attracting or repelling effect on birds, causing some deviations from the usual migration course. This is the effect of the leading landscape lines. Birds that fly in both narrow and wide fronts can follow landscape lines. The desire to fly through certain types of terrain or, on the contrary, to avoid some areas, is sometimes more pronounced during the flight than the desire to move in a certain direction. Also landscape lines are used for orientation.
8. Main flight paths
There are places on the globe over which huge masses of migratory birds move over certain periods every year. The elevated concentration of birds there is usually dependent on the topography and in most cases has deep historical roots. In the autumn, on these paths, birds accumulate more than in spring. This partly depends on the fact that during the period of migration to the south, the number of migratory birds is greatest (after all, autumn migration occurs just after reproduction and the annual maximum of the population is reached), partly because in autumn the flight takes place at a quieter pace than in spring. Before setting off, the birds gather in flocks in places where there is a lot of food and wait for the first fine day. In the spring, many species migrate faster: at this time of year, birds rush to nesting sites. There are many places in Europe where birds migrate and make their own migrations. Examples of grand launch sites are the Falsterb in Sweden and the Bosphorus in Turkey. Other places of paramount importance for flights and periodically concentrating the mass of birds are Cyprus, Cape Bon in Tunisia, the Western branch of the rift valley in Africa, the Greater Kachsky Rann in North - West India, the Polka Strait between Southeast India and Sri Lanka, Mount Frazers Hill in Malaysia, Longitudinal Dalton Valley - Pass on Luzon Island in the Philippines.
9. Schooling and migration alone. Speed, height of flights
Many species of birds, and perhaps most of them during flights, gather in flocks, even if this is not typical of them in other cases. The number of birds flying together increases during the flight. In places of rest new flocks join them, and in the end of the day the total number of birds becomes huge. Dunlin, golden plover and sometimes Icelandic sandboxes usually form the largest flocks of birds of the same species. Along with giant flocks, the same species can join together in small groups or fly alone, i.e. they show a very large plasticity in their migration behavior.
Flights fly in flocks like herons, storks, geese (migrate in families), ducks (in many species, males migrate separately), swifts, swallows, cranes, gulls. The composition of the flocks in sexual or age relations is quite different. In many birds of prey, young animals migrate earlier than adults.
It was found that flying in packs gives some types an aerodynamic advantage. This is especially true for flocks of large birds. Some species fly "in single file", for example, cormorants (LATYN), others on a wide front, for example, a black brant (LATIN), another type of flight - a wedge, characteristic of cranes. However, the main reason for the formation of flocks - the desire to unite in the period of flights. Also the group behavior of birds is important for their survival both in the air and on the ground; the formation of flocks can neutralize many adverse environmental factors and dangerous elements.
Many birds make long non-stop flights over the seas and deserts. The question arises: is the risk and significant energy consumption compensated for by the benefits that birds receive as a result of long and difficult flights? The fact is that development along this path was guided by natural selection; long-range migrations in so many species are important for their survival.
The average speed of movement of birds during seasonal migrations would be impossible to determine if there were no data on repeated encounters of ringed birds on the same day when ringing was carried out, or the next day.
The flight speed of some banded birds
Interesting comparisons of the average speeds of movement of migratory birds observed by ground-based observers were made by Meinerzhagen. It turned out that the speed can vary quite significantly in the same species depending on which terrain the bird flies, and also it flies in a flock or alone (movement in the flock is faster). The highest values of flight speeds - 96 km / h were recorded for mallards and some birds of prey, and for the latter, movement was taken into account in strong tailwind. Other high flight speeds were determined for the Gray Crane (more than 100 km / h), jackdaws and ordinary quail (91 km / h), eagles (86 km / h), starling (78 km / h), rook, turtle dove, chibis and the average curlew (72 km / h), geese (70 km / h), falcon (59 km / h), yellow wagtail (48 km / h). In general, birds move during seasonal migrations faster than during other movements, not counting, of course, hunting and chasing. Falcon, rushing for prey, can reach speeds of up to 228 km / h.
In general, during migration periods, birds fly at a speed that is largely determined by meteorological and orographic factors. Since they are not always favorable, the speed is not very high, especially during the autumn flight. For many species, the autumn flight between northern Eurasia and South Africa stretches for many months.
The average movement height of most migratory birds, judging by the radar data, is 1100-1600 meters above sea level, but many of them often fly at altitudes of only 100-130 meters. At night, the flight takes place at higher altitudes than during the day, and in spring at higher altitudes as compared with autumn.
Usually, many long-distance migrants fly 9-10 thousand kilometers twice a year, which in itself is not a small test of strength. In terms of distance, the migration of the Arctic tern is unparalleled: its flight from the Arctic to Antarctica and back is 34-37 thousand kilometers. It was found that ringed birds flew in one direction 18-19 thousand kilometers. The question arises - whether polar terns rest during this journey. It is known that these birds, like other terns, reluctantly sink to the water surface or do not do it at all. The share of rest they need is land or a floating object. But the Arctic tern, being in flight, is able to obtain food from the surface of the water, which is not available to all migratory birds.
Listliterature
migration seasonal bird preleth
1. Great Soviet Encyclopedia (Volume 16) Birds Migration - Moscow: Soviet Encyclopedia Publishing, 1974. - 207 p.
2. Griffin D. Birds fly lane. from English - M. 1966 - 101 p.
3. Grishchenko V.N. Flyways and the evolution of birds - M .: 1995, - 48 p.
4. Dolnik V.R. The migratory state of birds, Mysterious flights - M., 1979 - 125 s, 165 s.
5. Curry - Lindal K. Birds over land and sea. - M., Ed. Thought, 1984 - 12-153 p.
6. Mikheev A.V. Flyways and a wide front span of birds - M., 1992 - 298-316 p.
7. Sokolov L.V. Why migratory birds return home. - M .: Science, 1991. - 119 p.
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Almost everyone knows about migratory birds. In early spring, most of the bird population arrives in the harsh Siberian region from the south, and in late autumn it flies back to heat. But only experts know that migratory birds fly in their own special ways.
These migratory routes evolved over thousands of years. These paths are called transit (or migratory) paths (Figure 1).
Picture 1
The flyway is a section of the migration range of each bird species, where seasonal migration takes place with minimal energy expenditure, i.e. is the best way to spring and autumn flights in these conditions.
Following the geographical features of the location of water bodies, migratory birds in the western and eastern hemisphere fly their own ways. Ornithologists, on the basis of many years of research into the migration of waterfowl, distinguish flyways of various levels.
The theory of flyways was advanced in 1874 by I.A. Palmen and received further development in the works of MA. Menzbir, N.A. Severtsov. The greatest contribution to the development of the theoretical foundations of the forms of migration of birds was made by the work of P.P. Sushkina, A.N. Promptova, A.Ya. Tugarinov, and later AV Mikheeva, E.V. Kumari, on the Asian continent - E.I. Gavrilova, V.R. Dolnik.
Some authors associated the origin of migrations of birds with the resettlement of species, therefore, the paths of movement should follow the paths of historical settlement. A.V. Mikheyev, on the contrary, argues that these two phenomena are based on completely different causes and patterns.
The flyway of a higher order can be traced on the scale of a whole continent or even two continents. This flyway can be called continental, it connects bird nesting sites with wintering grounds. In Figure 2, you can see 5 global continental flyways:
Figure 2.
Within the continental flyways, paths of lower order are distinguished. Experts call them migration corridors (or second-level flyways). These corridors lead from specific wetlands, where waterfowl usually nest, to the first-level flyway. Second-tier flyways can be called regional or local flyways.
The largest migration routes have their names.
Let us dwell on the main directions of the flyways, which are kept by birds nesting in our country. These areas can be divided mainly into two groups: coastal and continental.
The first are species whose life is tied to water and which inhabit the sea coasts; these are various seagulls, species of the family of auks, eider, cormorants, some waders. In the north, in the arctic and subarctic parts of our country, two such directions can be called: one runs approximately from the mouth of the Lena along the shores of western Siberia and Europe; in the region of the Barents Sea, their paths branch off: the more northern direction bypasses Scandinavia, and its other branch, through the White Sea, turns south, crosses the Lake District and goes to the Baltic Sea, from where it continues to the Atlantic coasts of Europe. This area is called the White Sea-Baltic. Every year more than a million waterfowl fly here in spring and autumn. The species inhabiting the coast of the Polar Sea to the east of Taimyr, fly in the opposite direction to the east, reach the Bering Sea and mostly wander south to the shores of Kamchatka, and then fly along the Kuril Ridge to Japan, partly and southward, to the Philippine and Sunda Islands . Some species living in the far northeast of Siberia fly to the shores of Alaska, then descend to California and south. The coastal inhabitants of the Sea of Okhotsk migrate along the Asian coast to Korea, sometimes fly to the islands of Japan, and partially reach Formosa and the coasts of China.
Difficult is the picture of flights over the mainland spaces of our country. The bird population inhabiting them is settled in various geographic zones and has its own ecological attachments. These factors influence the development of destinations and routes of annual flights. The vast majority of birds inhabiting the European part of our country, and partly the north of the Ural region, fly off for the winter in the western and south-western directions. Some of them linger in the middle zone of western Europe; others fly farther, to the shores of the Mediterranean, to northern Africa, while others, such as storks, swallows fly over the equator to southern Africa.
The bird population that lives in the middle and northern strip of western Siberia, including the Ob basin, migrates mainly to the west, and, apparently, its path goes mainly through the southern Urals and the lower reaches of the Volga. However, here, the paths of various populations probably cross, some of which follow further to the west, others from the lower reaches of the Volga go south along the shores of the Caspian Sea and find their winter apartments in Transcaucasia, Iran, and Afghanistan. This applies to the birds that inhabit western Siberia proper, but if we take the spaces that make up Kazakhstan east to Balkhash and Altai, then at least such birds as mallard ducks, sviyaz, pintail, fly away through Central Asia to the south to India. Both in this latter country and in the closer-lying Iran and Afghanistan birds migrate for the winter from the Central Asian republics of our country. For many species, such areas of Central Asia as the lower reaches of the Atrek, certain areas along the Syr - and Amu-Darya, Murghab, Tejenu and themselves are the wintering grounds for birds tied to the water - ducks, herons, cormorants. These, apparently, are the birds living in central Siberia, in the Yenisei basin, and by ringing it is established that from Indian wintering it is here that the path of some species nesting in Central Siberia lies. The specified Turkestan direction for the birds of the Yenisei Siberia is not the only one. Proof of this is a well-marked passage both in the region of the upper Yenisei and in Mongolia. In the northern Gobi, as in other parts of Central Asia, there is a passage of many species nesting in Siberia, including in the Siberian Arctic zone. From which parts of Siberia, where and by what ways deep into Central Asian spaces penetrate the animal geese, various little birds, many passerine, remains completely unknown.
More can be said about the passage of Siberian birds bypassing Central Asia from the east. This direction is made in Transbaikalia. A very large number of species inhabiting middle, and partly western Siberia, fly first east to Dauria. Inhabitants of more northern parts of Siberia, from the Tungusok system, from the Lena basin, and part of the Kolyma, flock here. This powerful stream of migrants then rushes to the south, generally adhering to the Great Khingan, in order to then again be divided into a number of channels. Some follow further to China and Indochina, others to India, part goes to the Philippines and the Sunda Islands, and some of the following reach Australia and even New Zealand. In general, for the birds of eastern Siberia, the Khingan flyway by the number of species that follow them can be considered one of the most important. The rich and peculiar fauna of the birds inhabiting Primorye and the Ussuri region, for the winter flies to the same countries as the migrants of the Khingan route, but descends to the south through Korea and Manchuria. Some species nesting in the Far East fly to Japan for the winter, for example, ducks. Above, as a coastal route, from Kamchatka along the Kuril Islands to Japan, there is also a considerable number of non-waterbirds, often forest birds; This interesting circumstance is explained in the history of this path.
The immense spaces of the West Siberian Plain for the study of flights represent enormous possibilities, which are increased by the fact that within its borders it has areas where birds remain in large quantities for the winter. All wetlands that are part of such routes are both nesting sites and resting places for migratory waterfowl.
At present, the movement of waterfowl across the territory of the Tyumen Region can be seen on the example of the West Siberian-Kazakh-Caspian geographic population, which runs along the Central Palaearctic flyway.
In the northern parts of this region, most of the ducks and part of the geese, as well as tundra swans and black geese fly in the autumn to the west - over the coast of the Kara and Barents seas, as well as through the Polar Urals, joining the stream of migrants following the East Atlantic migration route.
From Central and Eastern Taimyr geese fly also to the east and southeast through Eastern Siberia. Much of the geese from the tundra regions of Taimyr and Gydana migrate to the south-west through the basins of the Taz and Pur rivers. Sometimes from the middle course of the Pura there is a flight of geese in a westerly direction towards the Ob. In the fall, geese fly from Yamal in a smaller amount to the Ob valley than in the spring. Part of them from the mouth of the Ob River should be in the Poluya basin and the headwaters of the Yarudey, again going to the Ob River in the Khanty-Mansiysk region. Within the taiga zone, the area of increased concentration of migrants (mostly ducks) is the valley of the Ob. The scattered flight with the general southern and south-westerly direction is observed in the entire taiga zone. From the lower reaches of the Ob and, probably, from other areas, a part of the whoopers swans, singas, turpans, and the sea black-out fly to the west for wintering grounds located in Western Europe. At the latitude of Khanty-Mansiysk, in addition to the main direction (south, south-west), migrations of geese and ducks are observed in the western direction. Here, in the sub-zone of the middle taiga, the bean gum migrates eastward - the valley of the Ob.
The number of waterfowl migrating through the taiga zone of Western Siberia reaches approximately 17 million individuals - taking into account the departure of some birds from the tundra and forest-tundra regions to the west and east (outside Western Siberia) and taking into account the migrations from Taimyr tundra to about 0.75 million geese (Figure 3).
Figure 3.
In the tundra, forest tundra and taiga zone of the Middle Region, 20-25 million waterfowl migrate. However, some birds deviate from the general south-west direction and fly away from the Middle Region. So, from the tundra zone of Western Siberia, about 200 thousand river ducks and 2 million diving ducks (mainly sea-wolf) migrate out of the region to the western direction. At the same time, about 500 thousand white-fronted geese and 250 thousand humennikov migrate to the territory of Western Siberia from Taimyr. From the forest tundra and northern taiga about 2.3 million diving ducks and 30 thousand humennikov fly to the west. Also, about 1 million river ducks and 1.38 million diving ducks migrate westward from the middle taiga subzone. From the subzone of the southern taiga about 500 thousand Gumennikov fly away in the western and eastern directions.
In the forest-steppe regions of the Central region of Russia, the largest flows of migratory water birds are observed in the Tobol-Ishim interfluve. Probably there begins a noticeable division of the migration flow into 2 general directions: the south-west - towards the Caspian-Black Sea and North African wintering grounds and the southern direction - towards the Indo-Pakistani wintering grounds. This separation of migration flows is particularly noticeable in North Kulunda and in many parts of Kazakhstan. According to visual observations, the south-western (sometimes western) and southern directions are clearly expressed here. Such a fan of migrants expansion is confirmed by the analysis of ringing data, which shows the connection of West Siberian birds with European, Mediterranean, Caspian wintering, and Central Asian.
The number of waterfowl that fly through the Tobol-Ishim interfluve since the end of the autumn molt is estimated at 19 million, and in some years up to 25 million individuals. In the Barabinsk and Kulundinsk forest-steppe - approximately 2-3.5 million individuals.
The migratory stream of Russian waterfowl of the south-western direction covers North Kazakhstan (south to the middle part of the Turgai depression) and goes to the Northeast Caspian, where it is divided into two branches. One of them goes through the Northern Pre-Caspian Sea to the Manych Valley, Eastern Priazovye or passes somewhat north of these areas. Further across the Northern Pontic and the Crimea, waterfowl of this migratory flow widely fly away through the winters of Southern Europe, the Mediterranean and North Africa.
Further, the span is distributed across the Tyumen, Kurgan, Omsk, Tomsk and Novosibirsk regions. After the last two, about 400 thousand geese, 1 million river ducks, 500 thousand diving ducks migrate outside the general direction.
In the zones of the steppes and semi-deserts of the central Asian part of the Central Region, the main migration flows are divided as follows. In the direction of the steppes and semi-deserts of the Azov-Caspian Sea, about 7.04 million river ducks, 5.59 million diving ducks, 953 thousand geese and 2.074 million coots migrate. About 4.125 million river ducks, 1.521 million diving ducks and 840 thousand coots go to the South Asian winterings. About 700 thousand river and 500 thousand diving ducks migrate to western European wintering through the Orenburg region (Figure 4).
Figure 4.
Such is the scheme of the main directions of annual migrations of birds of our country, including the Tyumen region and adjacent territories.
ornithologist migratory bird banding
Migrations are characteristic of many animals, what is the peculiarity of bird migrations? Team "Carnivores" Armavir Head: Irina G. Rogozina To fly or not to fly?
Hypothesis The peculiarity of the migration of birds is that they fly away to warm regions, in order to save their life during the cold season. Research Plan - Examine information on this topic. - Learn what migration is and what are the features of bird migration. - Find out whether all birds migrate. - Learn how birds understand where to fly. - Formulate conclusions.
Migrations of animals, movement of animals, caused by changes in living conditions in habitats or associated with the cycle of their development. The former may be regular (seasonal, diurnal) or irregular (during droughts, fires, floods, etc.). The second ones ensure the distribution of the species and can occur in the larval stage (in sedentary animals — ascidians, corals, sponges, etc.) or during puberty (in most animals). Migration Migration, or migration of birds, implies the movement or relocation of birds associated with changes in ecological or feeding conditions, or reproduction characteristics. The ability of birds to migrate contributes to their high mobility, inaccessible to most other species of land animals.
Not all birds migrate
Variety of birds
Sedentary birds Birds that live in the same area all year round and do not make any regular movements around the area. Strictly sedentary. Birds spend their entire lives within a small nesting area, without going beyond its borders, even in winter (some species of sparrows, gray dove). Semi-ridden. Birds that go beyond the nesting area and spend the winter in its immediate vicinity (hazel grouse, black grouse, common bunting). Jackdaw Grouse
Nomadic Birds Birds that, after breeding, leave the nesting area and make continuous movements until spring, moving away tens, hundreds and even thousands of kilometers. Representatives: tit, nuthatch, jay, crossbill, siskin, bullfinch. schur waxwing
Migratory birds Birds that after breeding leave the breeding area and winter migrate to other, relatively remote areas, which lie both within the breeding area of the species, and far beyond its borders. Representatives: Thrushes, ducks, geese, finch, lark, warbler. Kulik Tsaplya
In many parts of the world, the change of seasons leads to the fact that birds can live there only part of the year. For example, in the northern hemisphere in summer conditions are very favorable for bird nesting. Thus, the birds have all the conditions in order to survive and raise offspring. However, in winter there are cold, in many cases frosty and snowy. In such weather conditions, birds can not Why do birds migrate? find enough food in the winter and may die of starvation. Many bird species cannot survive at low temperatures. That is why they fly south.
They fly to the south until they reach suitable for wintering places. Some birds fly even more southerly than they need. Perhaps they instinctively return to where their ancestors hibernated. Where do the birds fly? Migratory birds can be divided into several types: - migrate over long distances - full migrants; - Migrates for minor distances - partial migrants.
Rural and urban swallows fly in small flocks. They feed on insects in flight and descend to the earth for a night's lodging every night. Warblers fly mostly at night. Many of them fly non-stop for several days. Sea birds need wind to fly. In calm weather, they sit on the water and wait for the wind. Predator birds, storks and cranes are too large and use soaring flight when traveling long distances. They find the ascending (thermal) air currents and rise in them, using the properties of these streams, hardly flapping their wings. How do birds migrate?
The location of the birds in the flock
Birds use three main ways to determine the correct path: - They can react to the Earth’s magnetic field and find the path with it. During the day, the birds are guided by the sun. Since they see polarized light, birds can navigate even when the sun is out of the clouds. At night, the birds are guided by the stars. They learn a map of the starry sky while still in the nest. How do birds find their way?
Many bird species have been studying migration routes for several years. Swans, geese, and seabirds explore migratory paths, traveling with adult experienced birds. They remember the main landmarks that lie on the path of migration: river valleys, mountains, and bends of the sea coast. - Other birds, like a cuckoo, must find the right path on their own. Such birds instinctively know the correct migration route and wintering sites. How do birds find their way?
Andrei Shalygin: It has become fashionable to follow the flight paths of migratory birds according to Google Maps and other geographic information systems. Many years ago I was one of the first to give hunters a general understanding of this process using the kmz modules for Google Planet Earth and the sources of such modules that are used by specialists in accounting and studying seasonal migrations. For example, in 2009 it looked something like this \u003e\u003e\u003e And there were a lot of such publications from different services. We also gave a general theory on individual species of bird, for example, including historical, scientific, educational, on goose and brant, ... squirrel, .. and so on.
Belarus - the second week of hunting 2014 (on the preview of the article - the first week of 2014)
As a matter of fact, the spring this year is early, temperature records are already standing. The duck has already sat down on the Moscow River, in all forums the hunters exchange information about what is flying, how much and where. The overflights are shifted every year, the old places stop working, the time limits are set by the Regionals, the hunting has been banned somewhere, and it is still banned somewhere. In the north, the last seasons are still hunting - not hunting, but slaughtering after the fact. So once again telling that where and how many flies too - a double-edged sword.
If you take Belarus, then the goose there has long been going waves, hard and massively. So basically, everyone who waited for the season to open it first - they have already returned from Belarus and went to pick up the goose. Two weeks lasted car rally gooseman. It was worth it or not - they know better, but Belarus still does not prohibit spring hunting, but the main first waves have already passed there, and now they are going steadily in small-scale.
Belarusian ornithologists set an absolute record of birds accounting - on March 20 of this year, they managed to count 200 thousand birds per square kilometer on the Turovsky meadow. They started recording similar observations of mass flights in 1994 and, as the ornithologist said, the director of the Belarusian Bird Ringing Center Pavel Pinchuk to the Wildlife of Belarus website, most likely did not see such a concentration of migratory birds on the territory of Belarus. About 60% of the birds observed were ducks. And most of all sviyazy was observed (about 96 thousand). Ornithologists have seen both mallards and pintails. It was noticed about 40 - 60 thousand turukhtanov. Ornithologists observed this number of this type of waders two years ago, but then, as Pavel Pinchuk noted, observations were made in early April. In addition to ducks and waders, large flocks of gulls (up to 3–5 thousand) and geese (up to two thousand individuals) now spend the night on Turovsky Meadow. Recall that the reserve “Turovsky Meadow” was established in 2008 on the territory of the Zhitkovichsky district of the Gomel region. This place is not only a popular stop on the migration route for migratory birds, but is also known for nesting around 55 species of birds, some of which are rare and protected both at European and national levels.
Several records of spring migration of birds in Latvia have been registered. In early March, several records of spring migration of birds were recorded in Latvia. Already on March 4, a white wagtail was seen in the Dviete Ilukstsky Volost, and on Ungur Lake on March 6 an ordinary Kestrel. In the vicinity of Bebrene, birdwatchers on March 7 saw a marsh moon, on March 10, at Lake Babites - Remeza. On March 11, the earliest arrival in Latvia of a white heron was registered, which was seen on fish ponds in Kvapana and on Kaniera Lake. This year's record was set by a seroschekse grebe, which was seen in the Rudbargi Skrunda Volost on March 14. Last week, migratory birds were also noticed, which never returned to Latvia so early - on March 22 they saw a pillowfish near the port of Mersrags, saw a cedar in the Tukums parish, and on March 23 in the flood plain Sveta - turukhtana.
In the Volgograd region, of course, the bird returns a little later, but it already fits. Rooks, swans and ducks return. According to the observations of Volgograd ornithologists, the first migratory birds are already returning to the region: rooks, ducks, mute swans, starlings fly home. Other species of birds will return to their native lands closer to May. On the eve, employees of the Nizhnekhopersky Natural Park conducted monitoring observations on the assigned routes of the territories of the natural park for animals listed in the Red Book of the Volgograd Region. The flight of a flock of a gray crane was recorded. This bird is very rare in the park. Other migratory birds were also noted. Compared to last year, the state of the populations of these species of birds is stable.
Because of the early spring, migratory birds have already reached the Altai, and the unfrozen birds begin to hatch nestlings. Although spring and frowning, but it is early this year. Many birds have already felt this and are beginning to move closer to the places where they will nest. A couple of weeks ago, the first rooks appeared in the colonies of the Chase, but these were local, which winter in Barnaul in small numbers. But a couple of days ago, their mass arrival from already warmer places began. Together with the rooks fly and jackdaws. Somewhere outside the Science Town, going out into the fields, you can hear the lark singing high in the sky, flying to the northeast along the main migration route. Last weekend, advanced white wagtails, starlings, finches, kites and kestrels appeared. This means that in 7-10 days a mass flight will begin. But the northern guests: waxwings and tapworms, which fly to us only to winter, began their advance to the north. In the forest near Barnaul, big tits and puffy tits are already singing with might and main, woodpeckers are drumming, shouting nipples. If you are lucky, you will hear melodious songs of crossovers and a creaking song-whistling of bullfinches. Magpies and ravens are building nests with might and main, but owls - long-tailed owls - have already begun to hatch clutches.
The main first waves passed over Moscow, the first village duck en massekhimkinskoe reservoir, Pestovskoe, Pyalovskoe, Klyazminskoe, Khimkinskoe. The first waves passed over Rybinsky ...
According to our observers from the field:
On average, the situation with the 2014 spring migration of birds now looks something like this on this map. 40 goals went east at Bronnitsy, Ramensky pH MO. 03/24/14. 16-00. Chuvashia, Kanash 20pcs white-footed, east direction. Peter, 20 km to the south, a flock of 200 units sat down today on a potato field. Veliky Novgorod, the goose pulled up a little, yesterday saw more than ten packs, in Zelenka there are 500 heads in one of the fields, they call, they see everything in the whole district. Vladimir region (district of Murom). In a small puddle, a flock of bean goose was found in 9 heads In the evening, watched a flock of 13 goals, flew in the direction of Nizhny Novgorod. Fields are almost dry. A lot of larks, gulls and lapwing. Familiar were fishing saw swans. Voronezh, with. Nikolskoye - three flocks of geese (bean goose) passed to the south-east by approximately 300, 100, and 50 heads, respectively, from 17 to 20 hours. MO of Odintsovo. Over the city, a flock of geese about 15-25 pieces. The height of 200 meters. Flying gaggled. Gone towards Vnukovo. Moscow region Silver ponds: about 100 Gumenniki. Ryazan Region Mikhailovsky District: 50 pcs of white-fronted strictly to the east. Belgorod region, p. Maysky, two flocks with a total number of heads 50, heading south. Today I saw a flock of 30 heads in the north of the Yaroslavl region, they were walking low over the fog, there is almost no snow. In the Ryazan region. in Sasovsky district there is a large flock of geese sitting on Zelenka. Lipetsk, about 18 hours, a taboo of white-whelps of about 40 on oxygen to the north-west. In St. Petersburg, near the house I saw a wedge of geese, 40 heads, walked north-west at a decent height. Lipetsk: Goose flies to almost all areas of the region. Smolensk. Just over the city, a flock of 20 pieces flew by. ...
Today on the Moscow Canal
The traditional Orthodox feast of the Annunciation with the release of birds will be celebrated throughout Russia.
In the Children's Museum Center of the Tver State United Museum exhibits an exhibition of the department of nature. The exhibition is held on the eve of the traditionally held children's spring programs. "The Annunciation - the birds will be released." Spring is the time for birds to return to their homeland. Happy months of songs, dances, but also family troubles. Many birds come to us in the spring, bringing good news about the onset of heat and the awakening of nature, therefore people have long considered them good messengers and were always greeted with joy. With the appearance of the first thaws and up to the middle or the end of May, our migratory birds, who spent the winter in warm lands, return home one by one. Symbolically - the birds seem to carry the message from one people to another. They always return if they do not die on a distant and dangerous path. At the exhibition, visitors will be introduced to migratory birdsnesting on the territory of the Tver region. They find out how they return from the “winter apartments” in a certain sequence: from the first rooks that appeared in March to the swifts, arriving only by mid-May. The organizers hope that the exhibition will help visitors to get to know the world of birds better, to see their beauty and diversity, to give an opportunity to hear the voices of spring heralds. Visiting the exhibition will leave a mark in the hearts and minds of visitors and will help the survival of the beautiful world of birds, which, in turn, will thank all of us with cheerful singing!