Examples of animals seasonal migration list. Coursework: Biological and geographical features of the migration of terrestrial animals. What causes animals to form groups before migrating?

16.06.2019

Two breeds sea turtles make great migrations. Turtles start their lives in Japan, then swim 13,000 kilometers across Pacific Ocean to feed on crabs off the coast of Mexico before returning back to the beach where they were born to nest.

leatherback turtles start life in the Caribbean before sailing north into the icy waters of Nova Scotia in search of jellyfish. They are indifferent to the cold due to their massive size: they grow up to 1.8 meters long and weigh over 400 kg.

They cover 16,000 km following the jellyfish in the Atlantic Ocean.

2. Humpback whales.

humpback whales from southern hemisphere leave Antarctica to breed in warm waters Central America, far north off Costa Rica before returning home to feed. This is the longest migration of all mammals.

3. Wildebeest.

Each year, 1.4 million blue wildebeest in East Africa migrate 2,900 km clockwise around national parks the Serengeti in Tanzania and the Masai Mara in Kenya.
They chase the seasonal rains in search of a better life. One of the most big problems on their way is the crossing of the Mara River in Tanzania, where a huge population of crocodiles lives in anticipation of the wildebeest.

4. Butterflies Monarch.

The Monarch Butterfly travels annually from Mexico to Canada for the summer. One Monarch butterfly lives less than three months. They breed along the way, going through four generations during one migration cycle.
They fly to the same trees every year, despite the fact that not a single butterfly has ever been to them.

5. Deer.

6. Salmon.

The sockeye salmon travels further than any other salmon species. They are born hundreds of miles upriver in Alaska, spend five years at sea, then move back upriver to spawn, and then die.

7 Whale Sharks

The whale shark is the largest fish on our planet. They can reach 12 meters in length and inhabit warm waters around the world, but many feed near the Yucatan Peninsula before swimming away to Atlantic Ocean. Whale sharks have been tracked all the way from Yucatan to West Africa and back.

8. Swallows.

Swallows fly up to 19,000 km a year, migrating from the UK to spend the winter in South Africa.

9. Elephant seals.

Northern sea elephants breed off the coast of California, but spend most of their time in the waters off Alaska. Males and females have different migration paths: males follow predictable trajectories while females move in pursuit of prey.

10. Dragonflies.

Dragonfly migration is the longest among insects. Like monarch butterflies, dragonflies breed on the move, and their migration takes four generations. They migrate following the seasonal rains from India to Uganda.

11. Mountain goose.

Mountain geese fly higher than all the birds in the world, even higher than Everest. They spend their summers in Mongolia and migrate across the Himalayas to southern India for the winter.

12. Arctic terns.

Arctic terns make the longest migration of any animal, flying 70,000 kilometers a year. During the summer they breed in Greenland and then fly to the other side of the world to spend the Southern Hemisphere summer in Antarctica.

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Migration, (from Latin migrans) means resettlement. Migrations are widespread among animals of all the globe and are an interesting adaptation for enduring the unfavorable conditions that sometimes occur in nature.

In autumn, as foraging conditions worsen, the bulk of arctic foxes and reindeer migrates from the tundra to the south, to the forest-tundra and even to the taiga, where it is easier to get food from under the snow. Following the deer migrate to the south and tundra wolves. AT northern regions tundra hare hares at the beginning of winter undertake massive migrations to the south, in the spring - in the opposite direction. migration seasonal relocation animal

Animal migration occurs when different conditions and they are different.

Regular seasonal migrations of desert ungulates also depend on seasonal changes vegetation cover, and in some places - on the nature of the snow cover. In Kazakhstan, saigas in the summer stay more often in the northern clayey semi-desert steppes; in winter they migrate to the south, to the area of less snowy wormwood-fescue and wormwood-saltwort semi-deserts.

In general, migrations in mammals are characteristic of a relatively smaller number of species than in birds and fish. They are most developed in marine animals, bats and ungulates, while among the species the most numerous groups- rodents, insectivores and small predators- there are practically none.

Animals have periodic migrations, they are also called eviction. Periodic evictions - migrations include those that represent the mass departure of animals from breeding places without subsequent return to their former habitats. According to science, such evictions are caused by a sharp deterioration in living conditions, as well as lack of food, which is associated with the emerging high population density of the species, forest and steppe fires, severe droughts, floods, excessive snowfall, and other reasons. This shows that numerous circumstances can cause the movement of a mass of animals over long distances. Invasions - the movement of animals outside their homeland. Such movements differ from true migrations in their irregularity and long intervals between successive invasions. Sometimes they are considered as initial stages the formation of real migrations arising from explosive settlements - "emigrations". Invasion is like a safety valve triggered by excess population density. In itself, this favors the existence of the species only indirectly. In normal vivo population processes are in equilibrium, and population growth resulting in eviction rarely occurs. Invasion is a phenomenon, the disadvantages of which are striking, but which, at the same time, for a long time gives an advantage that more than outweighs the disadvantages. A typical example of these migrations is the migration of lemmings and squirrels. Irreversible periodic migrations are inherent ordinary squirrels. They (migrations) arise quickly in response to emerging unfavourable conditions. Migration begins in July-August, when the squirrels begin to feed on seeds and nuts of a fresh crop and discover their deficiency. Migration continues for about 6 months. Squirrels sometimes overcome up to 500 km or more. Proteins do not migrate in groups, but singly. Squirrel wanderings are periodically repeated every 4-5 years and greatly affect the yield of furs and the economy of squirrel hunters. The speed of squirrels during migration reaches 3-4 km/h.

Animals make seasonal migrations annually and at certain times of the year. These migrations are regular and reversible. Animals, leaving their breeding places, return to the same places when favorable conditions occur. Seasonal migrations are characteristic of Arctic fox, the main reason for which is food. Arctic foxes follow migrating lemmings, completely repeating the properties of their migrations. The migration of predatory animals is mainly associated with the migration of small animals that are food for predators.

Seasonal migrations are especially pronounced in places with a sharp change in habitat conditions from winter to summer, in places with harsh winter and hot, dry summers. This phenomenon has the character of a purposeful mass movement, although it is not always clearly visible. The causes of seasonal migrations are always complex. However, the most tangible of them is hunger. Another reason is the attack on animals by gnats: mosquitoes, gadflies, horseflies.

Seasonal migrations, in turn, are divided into horizontal and vertical.

Horizontal migrations are those when animals move from one place to another, changing environmental conditions within their typical landscape. Such migrations are typical for reindeer, seals and other animals.

Vertical migrations are understood as those when animals in the same season of the year find for themselves in the spring Better conditions in alpine regions in alpine meadows, and in autumn they descend to foothill pastures. Such movements are typical for the inhabitants of the mountains - goats, chamois and other ungulates. Mountain ungulates by the summer rise to the upper mountain belts with their rich herbage, in winter, as the depth of the snow cover increases, they descend. And in this case, some predators, such as wolves, are observed combined with ungulates.

Diurnal migrations are also known among animals - this is the transition of animals from places of daytime haulouts to places of watering places, salt licks and feeding. Daily migrations are characteristic of hares, deer and other animals.

All the aforementioned migrations are called active because animals carry them out with great excitement, they sometimes appear in settlements and in other places that are not typical of their habitat and often, unfortunately, remain unaccounted for.

In contrast to active migrations, passive migrations are also observed among animals, i.e., those when animals move away from breeding places and habitual habitat with the help of ice or water currents. For example, migrations of walruses, polar bears, arctic foxes are known, caught on ice floes, which were carried away by the current into the ocean to some islands. Hares and muskrats during floods, falling on floating objects or ice floes, go downstream for long distances. Different modes of transport play a significant role in passive migration. Especially characteristic is the settlement through vehicles mouse rodents. As a result of passive migrations, house mice, rats and other animals were settled almost all over the world. Many of the introduced species of animals get along well in new places. Thus, there is an increase in the area certain types harmful rodents.

Rodent migrations are of interest in the sense that many of them can be used in hunting and trade and in the control of agricultural pests.

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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, biggest, smartest, and even the most stupid of the representatives of the animal kingdom are going on a journey and overcome distances full of difficulties and adventures.

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

great migration
African wildebeest and zebra migration is the largest mammalian migration on our planet. Every year in February, the Great Migration begins in Tanzania. Exact date start depends on the beginning of the calving season, during which about half a million calves are born. They all head towards the fertile plains and forests of the western Serengeti. About 250 thousand animals die during the journey, which is almost 1800 kilometers

red tide
Christmas Island isolated in Indian Ocean, is home to 1,500 people and 120 million red crabs. Every year, tens of millions of burrowing crabs migrate to the sea to lay their eggs. This spectacle is truly unique!

Arctic tern
This little bird is the absolute champion in the length of the path during its migration. She flies to the Antarctic for the winter, and returns to the Arctic in the spring. During the year, the Arctic tern flies about 70,000 km. These birds are long-lived - they can live over 30 years. It is believed that during their life, they fly over 2.4 million km! That's enough to get to the moon and back 5 or 6 times!

Reindeer caribou
One of the most famous and large-scale animal migrations is that of the northern caribou. Their winter and summer pastures are almost a thousand kilometers apart, and reindeer migration is one of the most impressive phenomena. wildlife on the ground. Because of weather conditions caribou migration occurs each time in a different scenario and in different ways.

March emperor penguins
Although the migration of emperor penguins may seem short compared to other animals in more temperate climate, this journey is fraught with incredible difficulties and no one has the right to make a mistake. are forced to migrate not only because of the climatic conditions of the Antarctic winter, they are forced to migrate by the polar night, during which it is difficult to notice the predator. Migration routes are determined by the threat from predators. Despite all precautions, 20-30% of young animals die during the journey.

Return of the swallows
Every year on March 19th, the most famous swallows (Hirundo erythrogaster) of the San Juan Capistrano Mission in California return to their nests after wintering in southern countries, and leave them also from year to year on the twenty-third of October. Their annual departures and arrivals have been recorded by the mission staff for many years, and not once, even in leap years, there was no deviation in time. They fly about 10,000 km.

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

Lemmings
Usually solitary, lemmings may go on massive migrations when biological conditions strongly dictate the need to seek out new feeding grounds. Along the way, they become easy prey for wolves and foxes. Surprisingly, lemmings do not even try to escape. Often on their way they run into a barrier or a river and the rear animals push out those in front.

Passenger (passenger pigeon) pigeon
These birds lived throughout North America. In colonial times, they were found in such numbers that the trees bent under their weight. Up to a hundred nests of this dove could be counted on one tree. When the flock rose, a sound was heard, as during a tornado, and the sky darkened. Imagine how those who watched the migration of these birds felt. It is hard to believe, but this bird has completely disappeared - the last representative of this species died in 1914.

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

1. Africa. Every year, more than 1 million white-bearded wildebeests and about 200,000 zebras migrate to the waters, covering a distance of 485 kilometers through Kenya and Tanzania.

2. One of the most impressive migrations belongs to crabs from Christmas Island. About 50 million red crabs live on this tiny piece of land in the Indian Ocean. Once a year they run to the water and come back.

3. This time, the black-browed albatrosses chose the Falkland Islands to mate. Mountain caracaras carefully observe everything that happens the whole winter, they wait until the birds, with a wingspan of more than 2 meters, begin to lay eggs and breed. Albatrosses never leave their eggs unattended: the female or male is always nearby.

4. Every year, millions of saucer-sized red crabs on Christmas Island run over the slopes, cliffs and mountains into the water.

5. A single monarch butterfly, on its own, can never cover the distance of their migration from Mexico to northern Canada and back. Therefore, they turned this relay race with the change of entire generations into a way of life.

6. The Pacific walrus, which is not physically predisposed to long-distance swims, uses drifting ice floes for rest and mating, making its way from the coast of Alaska to the coast of Russia and back. Unfortunately the ice recent times getting smaller and smaller...

7. Western Wyoming National Park Today, the migratory pronghorn herd numbers only 200 heads, which is incomparably less than before. Always the migration of these animals was not easy, but today, in order 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 land migration (490 km) belongs to rare species elephants of Mali. Still, without constantly moving from one source of food and food to another, it is simply impossible to survive in the Sahara Desert.

9. This is a frame from the movie “ national geographic» about the migration of zebras in Africa. A large number of young mothers usually do not stand such a long test.

10. Great white sharks cover thousands of miles every year, traveling from Hawaii to northern Mexico.

11. Male sperm whales travel alone for most of their lives, overcoming hundreds of thousands of kilometers from ocean to ocean. But every year they sail to the Azores (Portugal) "to meet" with the same as they are, from where they go together to the females waiting for them.

12. Every day, adult red-eyed Rockhopper penguins descend to the sea to eat and again climb the steep cliffs where their chicks are hidden. After three months, the penguins return to the sea, preparing for the new season. While their chicks, in order to avoid death from albatrosses, try their wings and fly away from land. Many of them may not return there for more than 10 years.

13. Survival by yourself big fish in the sea, whale shark, however contradictory it may sound, depends on microscopic plankton. It is these inhabitants of the seas that this huge creature feeds on.

14. Mississippi River. White pelicans breed in the summer in North America, and fly south for the winter, reaching Central America in small flocks of 150-180 birds.

15. The migration of Pacific walruses directly depends on the movement of ice - in winter, when the ice expands, they swim to the south, and in spring and summer, when it breaks, they return back to the north.

16. An amazing migration can be observed on Lake Palau, where every day 5 million jellyfish follow: in the morning - strictly to the east, in the afternoon - to the west. At night, jellyfish dive up to 13 meters underwater, where they feed on the bacteria they need to survive.

17. Mexico, Michoacan: in a high-quality photo, the viewer can appreciate all the brightness and beauty of the migration of monarch butterflies.

First of all, the distribution of animals is influenced by climatic conditions, among which the main factor is the temperature of the habitat. Different types of animals have different ability to withstand temperature changes. In some species, this amplitude has a wide range, while in others it is very narrow. The requirements for the temperature of the habitat lead to the zonal distribution of animals.

In Africa north and south of equatorial climate followed by subequatorial, tropical and subtropical climate. The average monthly temperature in summer is about 25 - 30. In winter, high positive temperatures also prevail (10 - 25), but in the mountains there are temperatures below 0. The largest number rainfall in equatorial zone(average 1500 - 2000 mm per year). To the north and south of the equator, precipitation decreases.

The air temperature is constant here. Throughout the year, it fluctuates between +24 and +28. On land, precipitation exceeds evaporation. The soil becomes swampy, thick and high wet equatorial forests. In the Serengeti, animals undertake migrations 300 km long. From May to August, when it rains, ungulates, breaking into separate large groups, migrate to the south, because most of pastures at this time turns into swamps. In November-December they return back. Seasonal migrations of ungulates occur not only on the Euro-Asian continent, but also in Africa, in a country with a warm climate. The main reasons for them are climatic factors. When in tropical Africa the rainy period begins, semi-deserts and steppes come to life with their xerophytic flora (plants of arid habitats), temporarily covered with a bright carpet of spring greenery and flowers. Then migrations of mammals occur on free pastures. The beasts leave the sublime mountain steppe and the desert. Behind numerous herds of antelopes, zebras, gazelles and other ungulates, they follow large predators: lions, leopards and their cowardly companions - hyenas and jackals. When the rainy period ends and the plain burns out under the scorching sun, there is a reverse migration of animals.

Any species can establish itself in a new place and under new conditions, if there is enough free space or there is an unoccupied ecological niche in the ecological system, or if it has an advantage over another species that has previously established itself here and is able to displace it. In different parts of the world there are comparable ecological niches that can be occupied by species that are not even distantly related to each other.

Surprisingly, the sphere of wandering of domestic reindeer in Scandinavia is much wider. This is not only about limited movements, which are mandatory for all herd herbivores. Sometimes summer and winter pastures are separated by more than 250 km of difficult path, and the initiative of the transition belongs to the reindeer themselves, and not to their owners.

Asia and North America, on the contrary, are characterized by huge wandering herds of deer, which, obeying instinct, regularly set off. Neither rivers nor lakes stop animals. And often at crossings and on mountain passes, where deer accumulate in huge numbers, local hunters are waiting for them and arrange bloody slaughters. Migrating deer reach Novaya Zemlya. In their footsteps on the ice, the previously unknown Bolshoy Lyakhovsky Island (Novosibirsk Islands), almost 60 km away from the mainland, was discovered.

Lemmings: These small, predominantly nocturnal rodents inhabit the plateaus and mountain slopes of the Scandinavian Peninsula. For a number of years there may be very few lemmings in the area, but then there is an explosion of reproduction, as a result of which a myriad of these animals appear. Such periods are known as "lemming years". The reasons for such jumps in numbers are not yet fully understood, but the following can be assumed: at certain times of the year, some group of lemmings falls into exceptionally favorable conditions; a direct result of this is a rapid increase in the frequency and size of the litter. If such conditions persist for a number of years, there is an exorbitant increase in the population. But no matter how abundant food supplies are, after about 3-4 years there comes a moment when local resources are exhausted, and then mass emigration of the excess population begins. These emigrations are an impressive sight: thousands and even millions of lemmings set off on their journey in search of food. Contrary to popular belief, they do not start the journey in large groups, but singly. But when some natural obstacle, such as a river, is encountered on their way, countless hordes of lemmings are constantly concentrated on its banks. Sooner or later they throw themselves into the water and drown by the thousands in futile attempt swim across the river. The last act of the drama comes when the lemmings, having overcome all obstacles, reach the sea. Here, on the shore, a huge number of animals gradually accumulate, and the pressure of this living mass becomes so strong that they begin to rush into the water. A few lucky people get to the nearest island, the rest drown. And although we are now slowly beginning to understand the laws by which the suicidal emigration of lemmings occurs, it still represents one of the most exciting and thought-provoking phenomena of nature.

In those days, when human settlements had not yet stood in the way of ungulates and the possibilities of their movement were not limited to the territories of reserves and protected areas, the herbivores of East Africa made their annual seasonal migrations, crossing mountain ranges, crossing rivers and fording swamps to reach the green savannah during the rainy season or return to the forests with the onset of drought. AT last years settlements and agricultural lands have a very negative impact on the lives of wild animals, blocking their migration routes and forcing animals to be content with relatively small areas, which often result in overgrazing and soil erosion. These areas, where many species of large African animals are now preserved, may be the remains of lands that lie on the path of past migrations.

Huge herds of caribou stay in one place only during the birth of young animals, only about 14 days. The path of the caribou as a whole can reach 1000 km, but the northern Asian deer, yielding to the American ones, sometimes still go more than 500 km. The reasons for migration can be very different. main role, undoubtedly, plays the fodder of the land and the weather. Mass attacks of mosquitoes, horseflies and gadflies, which inflict unbearable suffering on deer, can also become an immediate reason for the start of migrations.

In addition to local movements over a more or less limited area, some mammals undertake much more distant travels during the breeding season. A classic example is the Arctic caribou, which annually cover distances from 650 to 800 km. All summer they graze in the tundra, but with the onset of July, they set off on their way to the south, through coniferous forests following the same routes. In other places, the hooves of thousands of animals that passed here one after another during an endless series of annual migrations made a path up to 60 cm deep in the stony ground. Equally large herds are characteristic of herbivorous animals of the steppes and savannahs. Males sometimes cluster in dense groups of 100 to 1000 heads, but such clusters of animals of the same sex are not stable, since mating occurs during autumn migration. In wintering places, caribou remain until the arrival of spring, and then set off on their way back to the north. On the way, deer are born to them, but even this cannot delay the herd for a long time. It rushes forward, regardless of any obstacles, and it happens that during crossings through deep rivers many deer drown. In one such place, 525 corpses of dead animals were found.

Before, when the bison were still very numerous on the American continent, they undertook their impressive trips, moving in a more or less closed circle, so that in winter the herds sometimes found themselves 650 km south of their summer pastures. Unlike bison, wapiti deer are much less prone to travel. Their movements are reminiscent of the vertical migrations of bighorn sheep, black-tailed mule deer and moose, which forage all summer high in the mountains, and as winter approaches, they descend into more sheltered valleys where the snow is not so deep and food is easier to obtain.

There was a time when African elephants committed long-distance migrations in order to provide themselves with a suitable shelter at the right time and throughout the year to have a sufficient variety of food, water and the salt they need. During such migrations, herds of elephants received a convenient opportunity to regroup, and at times it happened to observe large, up to 100 heads, accumulations of animals. These migrations were of two types: during the rainy season, elephants roamed randomly from place to place over a limited area, but, in addition, every year they made directed migrations, passing many hundreds of kilometers. In different seasons, elephants prefer different habitats: during the rainy season they stay in open spaces, and during the drought they hide in the forests.

The large mammals of the savannas can be divided into three groups based on their need for water.

The first category should include animals that constantly need water, such as the hippopotamus, which requires habitats where there is always enough water. However, this requirement does not prevent hippos in the event of drought or local overpopulation from making tedious land crossings from one river to another.

The second category includes species that have adapted to an arid climate. The need for water in such animals is very limited. For drinking, they either use surface water, or are content with the moisture contained in the succulent parts of plants, the roots of which go deep into the ground. Rhinos are such partially adapted to dry climate and non-migratory mammals.

The third category includes animals migrating or partially migrating in search of water. Among the representatives of this group, African elephants are in the first place, followed by buffaloes and, finally, predators such as lions, cheetahs, hyena dogs and hyenas, as well as the insectivorous earthen wolf, honey badger and Kaftian fox.

Every year, between Kenya, southwestern Ethiopia and Sudan, there is a massive, albeit little-studied, migration of animals. It begins in May, when the water level rises in the swamps of the upper Nile, and then the animals rush in a southeasterly direction to the arid regions on the border of Kenya. The roar of the countless herds of antelope covering the horizon is like the noise of a cavalry army on the march. The bulk of the animals are white-eared kobs, Tyangi bubals and Mongalla gazelles. Lions and smaller predators accompany migratory animals along the flanks.

In the past, the valleys of southern Ethiopia and northern Kenya teemed with a variety of animals by the end of July. The number of species of ungulates making their perilous journeys south was not in the hundreds, but in the thousands. Although the desert of Turkana blocked their way, this did not prevent them from spending three or four months here in contentment, until the need for fresh food prompted them to set off again to the north, where life-giving rains had already revived vegetation. By September, these places were empty again. In huge columns many kilometers long, the animals slowly and calmly left to the north, protecting the young from voracious predators, and the valleys again burned out under the scorching rays of the sun. Herds of oryxes and Grant's gazelles, scattered by migration over vast distances, again returned to Father's house. It was possible to drive for a long time through the area, on each square kilometer of which hundreds of antelopes graze, and then suddenly cross a sharp but invisible border, beyond which, for no apparent reason, you will no longer meet a single animal. One such boundary of such boundaries lay to the east of the Loile airfield. At the peak of the migration there were more than three thousand antelopes, while a few hundred meters to the east one could spend many days in a row without meeting a single animal.

When the dry season begins in June or July, thousands of wildebeest leave the Serengeti on their 320-kilometer journey west towards Lake Victoria, and return when the rains revive the parched pastures. Here you can also find huge herds herbivores (zebra, African buffalo and antelope of many other species), accompanied by various predators (leopards, lions, cheetahs, hyenas, hyena dogs and jackals). Most of these migratory animals limit their stay in dry areas while seasonal or occasional rains fall. In order to survive, they have to migrate between areas where they can graze during the wet and dry seasons.

Nomadism also has its downsides. Although newborn cubs of ungulates are more highly developed and mobile than the blind and naked cubs of most other mammals, nevertheless, even they usually remain motionless for several days or weeks after birth and hide in case of danger. In probably no more than 40 out of 185 different ungulates, the young follow the mother immediately after they get to their feet. The methods that help lurking young to remain unnoticed are similar even in completely unrelated species. Cubs that follow their mothers are less helpless than lurking ones and are more at risk of being attacked by predators. Species whose young accompany their mothers and flee from predators live in open spaces where they lead a nomadic or migratory lifestyle.