Introduction

Aerospace research methods - an option of remote research methods, a system of methods for studying the properties of landscapes and their changes using helicopters, airplanes, pilotable spacecraft, orbital stations and special spacecraft, equipped, as a rule, a variety of pulmoned equipment. Select visual, photographic, electronic and geophysical research methods. Application A. m. And. accelerates and simplifies the process of mapping and has great importance When organizing monitoring for the state ambient.

IN some cases Direct satellite observations are used to track major animal migration, on the body of which radio transmitters are strengthened, transmitting information about the movement and state of animals.

migration Animal Aerospace Observation

Migration of animals

Migration of animals, animal relocation to another habitat, caused by changes in the conditions of existence in places of former habitat or changes in the requirements of the animal to these conditions at different stages of development (ontogenetic migrations). Exist various forms migration. For example, Plankton performs daily migration, vertically moving into the thickness of the water during the day when the illumination, water temperature; Following it, organisms in food relationships are moving, for example. fish. Seasonal migrations occur in the fall in the worsening of the feed base, as well as in the spring - during the reproduction period. They are committed at about the same time under certain conditions and on already known routes. There are vertical migrations made by animals in the mountains, soil and reservoirs; latitudinal and meridional - in mammals and frame birds. Passionate fish (salmon, sturgeon) make anadromic migrations from the seas in the river and cadodromes - from rivers to the sea. Non-periodic migrations occur in extreme natural conditions: drought, fires, floods, eruptions, earthquakes, etc., as well as with increasing population density (overcrowding). Such migrations can significantly change existing ecosystems.

Animal resettlement is also possible when changing lifestyle, for example. with sedentary to movable in intestinal, uponogich Rakov; When changing the environment, eg in insects. Migration can delay for years, eg, larvae river eelwho spawns in the Sargasso Sea, more than 4 years are returned to the river basin Baltic Sea. The study of animal migrations is carried out different ways - From the labeling of animals and watching them to the use of Earth's Space Satellites.

Orientation of mammals

Since migration is one of the forms of mastering the surrounding space, no living being that does not have the ability to orientation, unable to master this space, cannot move in it are environmentally appropriate and useful for himself. And if it is so, then, therefore, the evolution of migration behavior was, first of all, through the improvement of abilities to navigate in space. But if migration is impossible without orientation, then the ability to navigate in space undoubtedly goes beyond the limits of migration tasks, providing the existence of a living organism in the environment. The ability to perceive objects and phenomena of the environment and on this basis to create an idea of \u200b\u200btheir location in the space inherent in all animals and accompanies any animal organism since its appearance to the world until death.

The ability to correctly navigate, vital to all creatures, but it is especially important for migratory species. As a rule, they use noticeable landmarks, and then the ability to search for the right direction through the sun, the moon or stars are not so necessary, becoming a valuable help in critical situations, and in cases where travel is performed on very long distances. An assistant in animal orientation, during migration, is not a mysterious "sense of direction", but vision, memory and sense of time.

The behavior of mammals differs from the behavior of birds and lower animals, primarily the fact that mammals have a big role playing than instinct. Therefore, among mammals, the ability to navigate heavenly Tel It is much less common, although many species have been specifically studied to identify such abilities. Nevertheless, scientists have discovered that field micewhich is somewhat characteristic and day-to-day activity is focused on the sun. It is very likely that large mammals Young animals can just remember the way to follow during the migration, while studying with parents and other members of their community, and then transfer the knowledge gained the following generations. The assumption that the mammal has a certain role in orientation plays the smell, experimentally confirmed only in the most latelyAnd here we may be on the threshold of interesting discoveries.

Smells and smells play a huge role in the life of animals. Smells are vital necessary information from the surrounding world, excite instincts, conditional reflexes, determine a positive or negative attitude to new environmental factors. The smell is one of the most ancient and most important feelings, with which animals are oriented in their environment.

Ways to study migrations

Methods for studying migration mammals are diverse and complex. This is primarily due to the fact that mammals live in different medium. Some of them live in ground conditions In the forest and on earth or in crowns of trees. Many of these animals have excellent climbing ability. Other landlands inhabit open spaces and have a rapid run, or in case of danger, they are instantly hidden under the ground (Surki, Susliki); Some of the mammals (dying, mink, ondatra, nutria, etc.) lead a semi-wheeled lifestyle near the rivers where they are mined.

Per last years On migration, special attention was paid by scientists around the world. Migrations began to study not only by direct observations, but also with the help of labeling. Already, the mission of many terrestrial animals gives an interesting result and forces the previous theories about their geographical location. Lew is more accurate and objective reflection of migration arising in nature.

Music beasts began to be used in 1924. At the beginning (in 1924-30), only 22 animals were labeled: 19 hares, 2 chips and 1 bat. These were insecure steps in a new interesting business. In the future, the lavetles of animals began to be introduced everywhere, and after 30 years, 16,693 animals belonging to 75 species were labeled.

V.S. Pokrovsky - an employee of the Commission on Environmental Protection of the USSR Academy of Sciences - back in 1959 noted that this type of research was significantly lagging behind others, because Until now weakly developed the method of catching and mammalian labeling.

At the first stage of the development of labeling, the funny animals were most labeled. Of 16.693 heads flashed for the period from 1924 to 1955, there were 11.248. Very little labeled hoofed animals and miserable rodents, although their migrations are of great interest to science. When comparing the development of ringing of animals and similar work on birds conducted in the same period, it can be said that the results obtained on mammals are insignificant.

The dream of animals is complex. Caught lively animals are usually very aggressive. Currently, scientists are experiencing different drugs, temporarily sleeping animals, especially large ground, so that various manipulations can be carried out with them. This idea comes from the experience of hunters of many tribes Southern Hemispherethat were used for hunt poisoned arrows. Already created a drug called KuraredPlocin, which has strong action On the muscles of the animal, temporarily relaxing it. The use of this invention can contribute to the mass labeling of deer, kulans and other hoofs and intensify the study of the migrations of these animals. A variety of dream approaches are also determined by morphological features mammals. Ground beasts have ear sinks that are strongly used when laughing. Underground and water is not.

Methods of laugh:

Tattoo . The ear of the animal is preliminarily wiped with alcohol, then tattooing tattoons put the number and the pieces of punctures are rubbed, which is usually well saved.

Ringing. Beasts that have no ear sink (dying, earther), the ring is put on the back paw, above the foot.

Cuts or penetration. Special tongs make labels on the ears and membranes of the paw, giving each label a conditional license number. Used when studying semi-water beasts (mink, otter).

If the ring is carried out in a wide scale, then this method allows you to do some conclusions and on the general stocks of game in this area, because The number of all individuals killed by hunters should be approximately the same percentage to the total number of this game in a given area, which is the percentage of mining of ocelled individuals to the number of rings of the rings: a / B \u003d x / s, where A is the number of heated birds, in - The number of returned rings, C - total amount individuals of the species mined by hunters.

Methodical difficulties of studying migration of animals are that they are in varying degrees They are available to direct observations of a person, due to a secretive lifestyle; Usually, all the animals at a meeting with a person quickly go and long-term, direct observation of them in natural conditions is almost impossible.

Much of the migration of beasts We are known from the works of Russian travelers of the XVIII century, Academicians I. Lephekina, P. Pallas and the XIX century A.F. Middendorf and others. In the period of their travels, they paid great attention to the relocation of animals.

To clarify the directions and ways of migration, it is important to return labels or a message about the mark of the extracted animals.

Dreaming is important scientific method Studying migrations.

The content of the article

Animal migration,the regular movement of the population of animals, during which the individuals from one habitat are moving to another, but then returned back. Such a journey along a circular route can be seasonal, like a spring or autumn flight of birds, and may require for its completion of a lifetime, as is observed in a number of Pacific salmon. Animal migrations have a pronounced adaptive (adaptive) character and arose in the process of evolution from the most different species. Examples can be associated with changes in water temperature. Seasonal movements of microscopic animals from the depth of the lakes in the shallow water or migration of whales, which fall from the supremour areas in the subtropics in the fall, where they appear on the light of their young, and in the end of the spring are returned back to cold water.

It is almost impossible to find at least two types of animals migrating an absolutely same way. Some move apart, others - only groups. Some move at the same time very slowly, and others - very quickly and practically without stopping. For example, the migration of the Arctic cracked is the annual flights from areas close to the North Pole (just a few degrees worthy of it), to areas where Antarctic ice is already found. On the other hand, some frogs are moved within a year for only a few hundred meters separating the river from the nearest pond, where their reproduction occurs.

In addition to migrations, animal populations can demonstrate and move another type. Some animals lead a nomadic lifestyle, and their movements are random in nature and are determined by specific conditions folding in certain places. For example, many large herbivores living with herds on the plains east Africa, move depending on the availability of food and climatic conditions in a particular area. These movements can occur by faded routes and are not associated with a mandatory return to its original place.

Another type of population movement is so-called. "Invasions" characteristic of some birds, mammals, as well as many insects. Invasions are usually observed in regions characterized by a harsh climate with sharp seasonal fluctuations. Well known example - brown lemming in arctic tundra. During the 3-4-year cycle, the number of these animals increases, and reaching a maximum, quickly falls. Upon reaching the peak of the number when the tundra literally tends to lemmings, they leaving their native places in the mass and go to a long journey. Many many are victims of birds of prey and mammals, while most of others die from diseases and exhaustion or drown in rivers and lakes or in the sea. However, some manage to survive hard time, and the population cycle begins again.

The Polar Owl, which also dwellings in the Arctic areas, is hunting not only on the lemming, but also on the hares. In those rare WimesWhen there are few lemming and hare, the polar owl in search of production moves to the south, sometimes getting even to California.

Related sudden invasions are sometimes observed in some semened birds, usually held in the same area. For example, such dwelling in highlands or in northern latitudes Views, as an Asian and North American cedishes, as well as Klest-Elovik, during the fault of the seeds of coniferous - their main foods - demonstrate disordered movements from the northern latitudes to more southern or mountainous areas in the valleys.

Among the insects, several types of locusts found in Africa and Asia and mass flights received particularly fame in cases where a very high population density is achieved and a shortage of food is observed. Moving into new areas, packs of locusts can literally eclipse the sun; Only very few remain in those places where they were born.

Unlike invasions, many other moves performed by movements are little noticeable. They occur slowly and sometimes lead to a change in the distribution area of \u200b\u200ba particular type. So, in the last 30,000 years, a person migrated from Asia through the Bering Strait to North America, and then moved to South until South America.

Providing food.

The farther from the equator there are those or other land animals, the more seasonal oscillations in their provision of food are noticeable. In the tropics, the amount of feed available, although changing depending on the alternation of drought and rain periods, as a whole, remains quite permanent during the year. As you progress north or soup begin to manifest seasonal changes. For example, in the tropics, insectivore birds have at their disposal a more or less permanent amount of feed, while Canada nesting on Alaska or in the north are faced with the fact that the feed is much in the late spring - the beginning of summer and very little at the end of the summer - early autumn; As a result, migration to the south from places that were so favorable during the nesting period, it becomes absolutely necessary for survival. IN winter months in the north North America And Eurasia ice shoves lakes, rivers and or etched shales that served in the summer the main stern faults of many waterfowl and marsh birds. It is not surprising that the flight to the south is completely obligatory both for these birds and for the various bird predators hunting on them.

Environmental analogues of insectivorous birds among mammals are small insectivative bats, active (unlike birds) at night. In northern latitudes, where in winter it is cold and there are no insects, many bats fall into the hibernation. Some species, such as gray bats ( Lasiurus. cinereus.) and it close relative - Red leather ( Lasiurus borealis) Migrate to the south, in warmer areas, where they remain active throughout the winter.

Reproduction.

In many cases, animal migration is associated with reproduction features. An example is some fish and marine mammals. Different kinds Pacific salmon fish Oncorhynchus spawn in the rivers of the west coast of North America and eastern coast Asia. Before the places of spawning, they sometimes have to rise up the rivers per thousand kilometers from the mouth. After spawning, adults perish die, and the fools raised from eggs grow and gradually roll into the sea. This journey can continue from a few weeks to many months, but only being in the sea, the fish begin to refill and grow very quickly. Having achieved half-breeding, what is required of one year to several years (depending on the type of fish), they return to the same rivers where they appeared. There they breed and die, repeating the fate of their parents.

Among the marine mammals, especially impressive migrations associated with reproduction demonstrate gray whales. During summer months They keep in the Arctic Ocean and the Bering Sea, where at this time an abundance of small marine organisms (plankton) arises - their main food. In the fall, accumulating a large amount of fat, whales begin to migrate to the south, in warmer areas. Moving along the Pacific coast of North America, most whales get to small lagoon from the western shores of the California Gulf, where they appear on the light of the young. In March, males, as well as females without a young begin to migrate to the north, and a few weeks behind them the same route followed and females with young. At the beginning of the summer, they all reach the cold waters of the Arctic and Subarctic. The goal of the journey to the south taken by the whale waters in warm water during the first few weeks of life, until they have formed a layer of fat capable of securely protect from the cold in the northern seas. Migration of whale north is primarily a return to the place rich in food.

Climate and light day length.

When studying migrations, it is very difficult to separate the influence climatic factors From those associated with the security of food or are dictated by the peculiarities of the reproduction. Biological productivity, creating a feed base for certain animals, in itself is largely determined by the climate, and in areas remote from the equator, the number of available food often depends on temperature. For many organisms, length is also very important. light daywhich regulates the normal cycle of reproduction.

The amount of light received per day, the so-called. Photoperiod, often directly stimulates the start of migration. In many birds, for example, the activation of the genital glands, as well as migration activity directly depend on the spring increase in the duration of the daylight.

Periodicity.

Some animal migration correlate with a lunar cycle. One of the most famous examples - Grunion ( Leuresthes Tenuis) - Small fish, inhabiting the coasts of California and the Northwestern regions of Mexico. From early spring before the beginning of the fall, it will spawn on sandy fellows, and the spawning occurs only during especially high (sisigine) tides observed in the first three or four nights after a full moon or new moon. During the spawning, ongoing 1-3 hours, females are thrown into the shore as shore, where they move the fluid movements, in which the caviar is postponed, immediately fertilized by males. The next surgery wave takes the females back to the sea, and from the deferred eggs, there are already nozzles in the next sisigine tide.

Changes in physiological state.

Migrations are very often associated with changes in the physiological state of individuals. In addition to the observed spring of close relationship between an increase in the sexual activity and the degree of readiness for migrations, both in the spring and autumn immediately before migration occurs a rapid increase in the fatters required for the energy supply of long flights. Some birds replenish their energy reserves, stopping during the flight for feeding, but others overcome huge distances almost without stopping. For example, a golden rzhanka ( Charadrius Apricarius.) The length of non-stop flight over the water can reach 3200 km. Tiny redhead hummingbird ( Archilochus Colubris), in summer living in the eastern regions of North America, the winter spends in Central America (from Mexico to Panama). In the fall, before migration, these hummingbirds are increasing about two grams of fat - this turns out to be enough to overcome more than 800 km of a path running over the waters of the Gulf of Mexico.

Migration routes.

Migrating, each population adheres to the same route that requires certain orientation tools. For a long time Animal navigation mechanisms seemed mysterious, but during recent studies managed to find out some questions. The first step was to define animal movement routes; For this, various mixing methods were used (such, for example, as ringing birds). If a large number of animals have been labeled, and then found in other places, you can not only trace the migration route, but also find out how quickly it happens and what is the participation of individual sexes and different ages in it.

Orientation on the sun and stars.

Vision is one of the fixed assets by which migratory animals are making their route. At the same time, there are some familiar landscape features, such as mountain ranges, rivers, lakes banks, or outlines of sea coasts. A certain role in orientation can also play the ability to recognize the position of the stars at night, and during the sun.

The study of heavenly orientation in animals began in the late 1940s from the works of the German ornithologist G. Kramer. Experimenting with migratory birds contained in captivity, he came to the conclusion that the Skvorts, being daytime migrants, are focused during the flights through the sun. A few years later, Franz and Eleanora Zaer managed to explain how they find their way of birds migrating at night. Working with small sparrows, they found that until the stars are visible, the movement of birds is chaotic. Additional experiences conducted in both Europe and America confirmed that many birds that are night migrants are focused on the stars during flight.

The ability to navigate through the Sun and the stars are characteristic not only by birds. Experiments with one of the types of Zeb ( Bufo Fowleri.), dwelling in ponds central districts The United States has shown that young, who have recently recently formerly naked individuals always move towards the coast. If the toad of this age is placed in a circular cage, from which only its walls are visible, the sun and not clouded by the clouds, they always move in the direction perpendicular to the line of their native shore. Even if you transfer these toads into some other place and put in the same cadcies, their movement will again be oriented in the same direction. Similar experiments with frogs, namely with a cricket quake, showed that they can navigate both in the sun and on the stars.

The orientation of the Sun is also detected by the White Perch - fish, inhabitants in many fresh lakes of North America. When the spawning period is approaching, these fish from the open part of the lake move to the shore. If they catch them where they spawn, and release in the same lake, but in its central part, they begin to move towards those places where they were caught (this was demonstrated by the help of floats attached to their backs with thin nylon threads) .

Orientation with the help of smell.

The orientation based on the perception of odors is extremely important for many organisms - from insects to mammals. An example of this is a monarch butterfly that makes large seasonal movements. The males in the fall are first round through a strictly defined route; Parking glands on their wings leave a smell trail, which is used for orientation flying females. Having reached wintering places, butterflies accumulate on trees in huge quantities, and in the spring they are started back to the north.

Several species of Pacific salmon, returning from the sea to the same rivers where they appeared on the light, focus with the help of the characteristic smell of the native river, captured in them from the first days after the oscillation from the cheekbones. This smell is defined as minerals on the catchment, and organic substancespresent in the waters of the river and gives it a chemical personality.

Flows.

Flows play important role In the life of animals living in the seas, as well as in rivers (especially where visibility is limited). Amazing migrations associated with oceanic currentsMake European and American Acne (representatives of the kind Anguilla.). Those inhabit Europe grow and ripen in rivers flowing into the Atlantic Ocean - from Scandinavia to the Pyrenean Peninsula. After spending there from 5 to 20 years and reaching sexual maturity, they roll into the sea, then drift with the Canary and Northern Equatorial currents, cross the Atlantic Ocean and reach Sargassov Sea - a specific area in the northwestern part of the Atlantic, where there are no flows and abundance Large floating in the surface of algae develop. In these places on big depth Acne multiply, then dying. The hatched larvae rises to the surface and with the waters of Golf Stream are transferred to the banks of Europe. This path takes them three years, and by the end of his acne are already able to move up river systemswhere left until the occurrence of puberty. Similar migrations make American acne living in the Atlantic Coast Rivers.

Awesome dangers.

Migration always requires consumption of stored energy, and the amount of energy necessary in order to cover long distances should be just enormous. Therefore, migratory animals always threatens the danger of physical exhaustion. In addition, they are easily become victims of predators. Successful overcoming the path of migration is also very large dependent on climatic factors. The sudden attack of the cold front during the spring flight of the birds to the north can have the fatal consequences for many birds, and fog and storms lead to the fact that they lose orientation and come down from the way.

A serious danger for many migrants is a person. Knowing the routes of fishing animals, people hunt them to mining or for other purposes, including pure sports. Various structures, such as television towers and skyscrapers, also serve as the cause of the death of hundreds of thousands of birds. Cleaning dam permissions creates obstacles to fish lifting upstream at spawning places.

Animal migration is the movement of animal population from one place to another associated with a change in climate conditions or with a period of their development. Gathering in herds and flocks, animals, birds or fish go to their travels, fascinating people with their beauty. What, in fact, you can see in the photo.

1. Africa. Every year, more than 1 million white beetroot GNU and about 200 thousand ZEBR migrate to the water bodies, overcoming a distance of 485 kilometers through Kenya and Tanzania.
2. One of the most impressive migrations belongs to crabs from the Island of Christmas. On this tiny piece of sushi that is in Indian Ocean, about 50 million red crabs live. Once a year, they flee to water and return back.
3. This time, the Black Albatrises, Falkland Islands chose for mating. Mountain Caracars carefully monitor the whole winter, they will wait for the birds, with the scope of the wings of more than 2 meters, will begin to postpone the eggs and remove the offspring. Albatrosse never leave the eggs unattended: a female or male is always nearby.
4. Every year millions of red crabs, size with saucer, on the island of Christmas running through the slopes, rocks and mountains into the water.
5. One butterfly monarch, in itself, can never overcome the distance of their migration from Mexico to Northern Canada and back. Therefore, they turned this relay with the change of whole generations into the image of their lives.
6. Pacific walrus, which is not physically predisposed to distant swims, for recreation and mating use drifting floors, overcoming the path from the coast of Alaska to the coast of Russia and back. Unfortunately, ice lately becomes less and less ...
7. Western Wyoming, National Park. Today, the migratory flock of Vilorogov has only 200 goals, which is incomparably less than what was before. Always migration of these animals was not easy, but today to descend from the mountains to the valleys, they need to overcome a large number of borders, channels, fences and other obstacles, which lead to a decrease in this, and so rare, species.
8. The longest migration on Earth (490 km) belongs to rare elephants Mali. Still, constantly without moving from one source of food and food to another, in the desert of sugar just do not survive.
9. This is a frame from the film "National Geographic" about the migration of ZEBR in Africa. A large number of young mothers do not endure such a long test.
10. Large white sharks overcome thousands of kilometers every year, making traveling from Hawaii to northern part Mexico.
11. Kashlota males most Life is traveling alone, overcoming hundreds of thousands of kilometers from the ocean in the ocean. But every year they sail to the Azores (Portugal) "to meet" with the same as they, from where they go to waiting for their females together.
12. Everyday adult red-eyed penguins of Rockopper descend to the sea to eat and again climb into steep rocks, where their chicks are hidden. After three months, the penguins are again descended into the sea, preparing for the new season. While their chicks, in order to avoid death from Albatrosov, test their wings and fly away from sushi. Many of them can no longer return there for more than 10 years.
13. Survival of Samoa large fish in the sea, whale sharkNo matter how contradictory it sounds, depends on microscopic planktones. It is these inhabitants of the seas that feeds this a huge creature.
14. Mississippi River. White pelicans are breed in the summer in North America, and the winter is flying to the south, getting to Central America Small flocks consisting of 150-180 birds.
15. Migration of Pacific walrus directly depends on the movement of ice - in winter, when the ice expands, they float to the south, and in spring and summer, when it breaks, return back to the north.
16. Amazing migration can be observed on Lake Palau, where every day 5 million jellyfish follow: in the morning - strictly east, in the afternoon - west. At night, jellyfish are immersed under water to 13 meters, where they feed on the bacteria necessary for their survival.
17. Mexico, Michoacan: on high quality photo The viewer can appreciate the entire brightness and beauty of the migration of butterflies-monarchs.

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Kingdom: Animals

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Kingdom: Animals

Animal migrations are one of the most touching and unusual phenomena Mother - Nature. The examples below confirm this in the full sense. The fastest, largest, most intelligent, and even, the most stupid from the representatives of the animal world are going to the path and overcome distances, full difficulties and adventures.

Butterfly monarchs
The mass migration of the monarch butterfly is perhaps the longest - both in the distance and in time, among other animal species. Several generations of butterflies, per year, in total overcome the distance over 3200 kilometers. From North America, they running from the approaching winter reach coniferous forests California and Mexico.

Great relocation
The migration of African GNU and ZEBR is the greatest migration mammalian on our planet. Every year in February in Tanzania begins "Great Resettlement". Exact date Beginning depends on the beginning of the seasons of the calf, during which about half a million calves are born. All of them are sent to fertile plains and forests of Western Serentheet. About 250 thousand animals dies during the path, which is almost 1,800 kilometers

Red tide
Christmas island, isolated in the Indian Ocean, is home to one and a half thousand people and 120 million red crabs. Every year, tens of millions of digging crabs migrate to the sea to postpone eggs. This spectacle is truly unique!

Polar colt
This little bird is an absolute champion in the length of the path during its migration. She flies to the Antarctic to wintering, and in the spring it returns to the Arctic. During the year, polar colt flies about 70,000 km. These birds are long-livers - they can live over 30 years. It is believed that during his life, they fly more than 2.4 million km! This is enough to get to the moon and back 5 or 6 times!

Northern deer
One of the most famous and large-scale animal migration is the migration of the Nordic Cariba. Their winter and summer pastures are at a distance of almost a thousand kilometers from each other, and migration nordic deer is one of the most impressive phenomena wildlife on the ground. Because of weather conditions, the cariba migration occurs every time different scenarios and different ways.

Marsh imperial penguins
Although the migration of the imperial penguins and may seem short compared to other animals in more moderate climates, the journey is associated with incredible difficulties and no one has the right to an error. Forced to migrate not only because of the climatic conditions of the Antarctic winter, the polar night force them to migrate, during which it is difficult to notice a predator. Migration routes are determined by the threat from predators. Despite all the precautions, 20-30% of young people die during travel.

Return swallows
Every year of the nineteenth Martha is the most famous swallows (Hirundo Erythrogaster), in the territory of the Mission San Juan Capistano in California, return to their nests after wintering in southern countriesand leave them also from year to twenty-third of October. Their annual departure and arrival are registered by the Mission staff for many years, and never even leap yearsThere were no deviations in time. They fly about 10,000 km.

Gray whales
Gray whales are the most popular attraction in California, but few know about long-term migration of these giants. Every year the journey back and back - from California and Mexico to the Aleutian Islands of Alaska and Bering Strait equals 18,000 km.

Lemmings
Usually living alone, lemmings can go for mass migrations when biological conditions strongly dictate the need to search for new feces of feeding. During the way, they become easy prey of wolves and foxes. Surprisingly, the lemmings are not even trying to escape. Often, on their way, they rest in the barrier or river and the rear animals pushed those who are front.

Passenger (wandering pigeon) dove
These birds lived throughout North America. In colonial times, they were found in such quantities that the trees were beyond their severity. On one tree, it was possible to consume to hundreds of nests of this pigeon. When the flock rose, the sound was heard, as during a tornger, and darkly heaven. Imagine that they felt observed the migration of these birds. It is difficult to believe, but this bird completely disappeared - the last representative of this species died in 1914.

Animal migration message will briefly tell a lot useful information And you will learn what is the cause of mass migrations of animals.

Animal Migration Report

Migration of animals - This is a regular movement of the population of animals, when the individuals of a certain type are moved from one habitat to another, and then returned home. Such travels can be seasonal, in the form of the autumn or spring flight of birds, or committed to complete their lives, like some species of Pacific salmon.

Why do animals make migrations?

Migrations are characterized by a pronounced adaptive adaptive character. They arose during evolution in many different species. Seasonal travel is often associated with a change in the temperature mode of water or air, and as a result, with a decrease in feed for normal life and young development. In general, it can be argued that seasonal migration Animals are an example of the manifestation of instinctive behavior when the body as if it pushes to finding new places to remove cold weather.

Seasonal animal migration Examples - Migration whales, microscopic animals, haircuts, swallows, cranes, flamingos, deer, swing, etc. So, whales in the fall leave the amateur areas and float to the subtropics to produce a young. At the end of the spring they return back into cold water. Birds fly out in warmer climes In order to wait for the cold, and the onset of heat in the native lands of animals arrive back.

It is noteworthy that all animals migrate in different ways and ways. Some species prefer to move in groups, others - one. Some move quickly and without stops, the rest is very slow. For example, arctic crags from year to year have long flights from the North Pole to the districts antarctic ice, and certain types of frogs are moved for several hundred meters from their habitat in order to acquire offspring.

In addition to seasonal migrations, a nomadic lifestyle and "invasion" are distinguished. Nomadic migrations are characterized by a random character and are determined by the specific conditions that have developed in places of climatic conditions of temporary animal residence. For example, large herbivores move with changing climatic conditions and food. Often they are not returned to their first habitats.

Another type of migration is "invasion". It is inherent in some birds, mammals and insects. Usually observed in regions with harsh climates and seasonal fluctuations. For example, brown lemming. In summer, their number increases greatly and comes to a maximum. Then they massively leave the spaces based and go on the journey. Then the cycle is repeated again and again. Or another example. In search of food or high density, the locust makes mass flights to new areas. The flocks of these insects are straight eclipsed by the sun.

So, the main causes of migrations:

• Property food. Away from the equator is noticeable seasonal changes that control the amount of food in a particular region. So, in the late spring and by the beginning of the fall of the feed is plentious to food. But in the fall, animals and birds migrate to places, more favorable for nesting and searching for food.
• Reproduction. Migrations are associated with reproduction. For example, marine mammals and fish leave their native waters and are looking for where warmer. So, salmon fish go to the west coast of North America or the eastern coast of Asia. Adult individuals after spawning are dying, and the fry, hatched from caviar, gradually return to the sea. So repeats the cycle again and again. Another example is gray whales. In the summer they live in the Bering Sea and the Arctic Ocean. In the fall, accumulating enough fat, animals migrate into warmer water, where young people appear in mammals. The males in March return back, after a few weeks behind them followed the females together with the young.
• Length of the daylight and climate. The vital activity of many organisms depends on the length of the daylight. For example, in many birds, sex glands and migration activity depend on the increase in the duration of the daylight.
• Periodicity. Migrations of some animals are closely connected to the lunar cycle.

The meaning of animal migration

The role of migration in animal life is large enough. Thus, they save their population from extinction in cold period time when little food. Also, migrations are often carried out in order to acquire the offspring, which returns later to their native places.