The Arctic Tern is the only bird that migrates from one pole to the other. These amazing birds in flight Why do birds fly like a wedge
Adult gray petrels (Puffinus griseus) reach a length of 50 cm with a wingspan of about 110 cm. These birds spend up to 200 days a year on long-distance flights. By actively migrating, gray petrels ensure that it is always summer around them.
Only the Ashy Tern can compete with the petrel in terms of flight range.
As a result of a study conducted by biologist Scott Shaffer and his colleagues from the University of California, it unexpectedly turned out that gray petrels turned out to be the living world's record holders for the length of movement during migration.
Schaffer and his collaborators tracked the migration path of gray petrels as they migrated between the coasts of New Zealand, Alaska, California and Japan. To do this, scientists used special radio beacons weighing 12 g, which collected basic data - temperature, flight altitude, position of birds, and the like.
Monitoring was carried out for two hundred days. Imagine the surprise of the researchers when they plotted the birds’ movement routes on a map and learned that during migration, the average length of the petrel’s flight was about 64,000 km!
Thus, it turns out that this is the largest migration path ever recorded in animals using precision electronic technology.
It also turned out that the flight lines resemble giant figure eights over the Pacific Ocean, that is, the birds do not fly around it at all, as biologists previously believed. This unusual path shape is associated with many factors, the most significant of which are food sources, temperature and even molting.
In the equatorial region, birds move the fastest, flying up to 1000 km per day.
In New Zealand, 33 chicks of this species were fitted with special recorder rings on their legs, recording temperature, light level and air pressure. A year later, 16 ringed birds returned to the same place, were caught and had their rings removed. The birds' route was determined by the values of illumination (that is, the length of daylight hours) and ocean surface temperature. Pressure readings provided information about when the petrel dived for fish.
After comparing all the data, the migration pattern turned out to be as follows: in the fall, at the end of April - beginning of May, the birds start from New Zealand to the east. Having flown over the Pacific Ocean, they find themselves in Chile, after which they fly to the Northern Hemisphere, visiting Japan, Kamchatka, Alaska, and California. At this stage, petrels fly 880 km per day. However, they do not eat until they reach their destination. After waiting out the New Zealand winter in the north, petrels migrate south, returning to New Zealand.
Doctor of Biological Sciences Alexander Tambiev.
Once a person watches birds at least once, he begins to want to learn as much as possible about them. It is especially interesting to look into the secrets of the life of migratory birds that make seasonal migrations. Every year, in a short period of time, birds cover enormous distances, adhering to constant routes, and fly to the same nesting and wintering places.
Slender-billed petrel.
Aluminum or zinc rings come in fourteen sizes - with a diameter from 0.21 to 2.2 cm. In the photo on the left, the ring is clamped onto the bird's foot with tongs.
Arctic tern.
Wandering Albatross.
Brown-winged Plover.
Routes of the most famous migratory record-breaking birds.
Birds, such as vultures or storks, use the rising flow of warm air to gain height and then soar.
Superb soaring allows large seabirds to glide over the ocean for hours without ever fluttering their wings. The figure shows how an albatross rises from the surface of the water, where the wind speed is lower, to the top, where the wind speed is much higher.
Grey goose.
Gray crane. Photo by Igor Konstantinov.
The great ancient Greek scientist Aristotle (384-322 BC) wrote about the fact that birds fly away to distant lands in the fall and return in the spring. He divided birds into those that live in the same places all year round, and those that fly away or “disappear” for a while, as do, say, pelicans, cranes or swallows. Aristotle explained the seasonal disappearance and appearance of some bird species with his own theory, according to which some bird species turn into others. The scientist also believed that many birds, such as storks, starlings, owls, blackbirds, ducks, and larks, hibernate during the cold season.
For almost two thousand years, Aristotle's views remained unshakable. Over time, reliable evidence of bird migrations became more and more numerous. In attempts to explain them, new, completely fantastic hypotheses arose. Thus, in the middle of the 16th century, the Swedish Archbishop Magnus suggested that swallows go to the bottom of reservoirs for the winter. Two centuries later, the Englishman Johnson supplemented this hypothesis with an original clarification: swallows first gather in a large flock, form a dense lump in the air and only then fall to the bottom of the reservoir.
Among the theories explaining bird migrations, there were also space theories. According to one of them, it turned out that birds spend the winter not just anywhere, but on the Moon. It was further explained that small and weak birds overcome such a huge distance on the backs of large, strong birds. And where does this “public transport” go later, the theory was silent.
Waymarks
By the second half of the 19th century, reliable facts appeared indicating that European birds fly to Africa and Southeast Asia for the winter. However, direct evidence began to accumulate only when ornithologists decided to tag the birds before their seasonal journeys. Instead of the previously existing ones, the most convenient mark - a lightweight stainless zinc ring on which the serial number, date and address are stamped - was invented and first used by a teacher from Denmark, Hans Mortensen, in the 90s of the 19th century. Since then, bird tagging has been called ringing. One movement of the tongs - and the ring goes on a journey along with its feathered owner, so that after some time in another country or even on another continent it is removed from the bird’s paw, the date and time are recorded and sent to the specified address.
Bird ringing has gained enormous momentum in the world. More than 50 million birds are ringed in the USA and Canada alone, and about 600 thousand birds are ringed in these countries every year. Approximately the same number of birds are ringed in European countries. In Soviet times, we banded more than 300 thousand birds a year, now it’s slightly less. Russia is a member of the International Committee for Bird Ringing and cooperates with national ringing centers in 55 countries in America, Europe, Asia and Africa.
Ringers act very carefully and sometimes cunningly. To catch the bird, they use almost invisible, very thin nets, which they hang in places where the birds fly over on long poles or tree branches. Thicker nets are laid out on the ground, and the birds get their paws entangled in them. There are even networks equipped with small “missiles”. When the birds, pecking at the food scattered on the ground, come very close, the “missiles” lift the net into the air, and as it falls, it covers the flock. And there are also nets that rise and slam shut, like a wallet. Bird traps are made in the form of a wide and long mesh funnel ending in a receiving chamber. For bait, food is poured into it. The following technique is also used: at night, migrating birds are lured with special lanterns and then covered with a net.
In addition to banding, there are other techniques for tagging birds. For example, gulls with white plumage are marked with pink or red paint. The long-lasting paint does not come off for a long time, is noticeable from a distance and does not interfere with the bird’s life.
On average, 3-5% of the rings are returned to the ringing centers, but this amount is enough to obtain accurate information about where and by what routes the birds fly away and return home.
Birds are very fast, extremely resilient, can fly at an altitude of several kilometers and at the same time have excellent orientation in the sky. Among them there are real record holders.
The absolute champion in terms of migration distance is considered to be the Arctic tern - a white bird smaller in size than a seagull with a black cap and a forked tail, for which it is sometimes called the sea swallow.
Terns nest on the northern coast of the Arctic and on ice-free islands. Offspring appear in early June. And by the end of the short polar summer, parental worries end. The chicks are raised and placed “on the wing”. It's time to go for the winter. This is where the terns show what they are capable of.
Once, on the coast of Labrador, a chick that was not yet able to fly was ringed, and 90 days later, a grown young tern was caught on the southeastern coast of Africa, 14.5 thousand km from the nest. It is likely that this was not the end of the journey, since terns spend the winter in the Antarctic seas. Another tern, which received a ring in our Arctic latitudes, was found off the southern coast of Australia; it flew at least 22 thousand km. Some terns fly to their wintering grounds across the Pacific Ocean, others choose a path along the western coasts of Europe and Africa, entering the Indian Ocean.
With the approach of spring, terns rush back and appear in their native places, actually circling the globe. One of the ornithologists said that for such a flyer as the tern, our planet is even too small.
Other seabirds are also capable of traveling vast distances. Take the wandering albatross, for example. This large white bird with huge, black-tipped wings with a span of up to 4 m spends much more time in the air than on water or land. The albatross uses air currents in flight, and this allows it to “glide” through the air without flapping its outstretched wings, which means expending a minimum of effort. It picks up prey from the water in flight. Neither the storm wind nor the multi-meter waves interfere with it; the majestic bird does not seem to notice the bad weather. When migrating, a wandering albatross can fly 15-20 thousand km over the ocean and circumnavigate the world in a year.
These flyers spend the nesting period on small islands of the South Atlantic. In albatrosses it is unusually long - more than 11 months. When the chicks begin to “fly”, the parents’ wanderings continue. The path of the albatrosses lies east along the forties latitudes of the Southern Hemisphere, nicknamed “roaring” because of the incessant storms. In these latitudes, the albatross flies around the Earth and after two or three years (for the next nesting) it finds itself on the same islands where it once hatched from an egg.
Another record holder for migration is the slender-billed petrel. Its native places are small islands of the Bass Strait, separating Australia and the island of Tasmania. The emerging chick is intensively fed by both parents, it quickly gains weight, becomes overgrown with fat, and after a month and a half weighs more than an adult bird. Feeding continues for three months, then the parents say goodbye to the child and fly off on their own routes. Left without care, the chick starves for some time, and then shows independence, begins to fly a little, catch fish, and finally flies for the first time to distant lands, only to return later.
First, slender-billed petrels head towards New Zealand, then turn north and, passing the islands of Oceania, end up off the coast of Japan. Then their route lies along our Far Eastern coast to Cape Dezhnev. Some birds fly across the Bering Strait and end up on Wrangel Island. However, the route does not end there. From our shores they head to the Aleutian Islands, from where they turn southeast along the North American coast. Having reached California, the birds fly across the Pacific Ocean to the eastern shores of Australia. Further a little to the south, and now ahead are the native islands of the Bass Strait and the old hole, which has dilapidated during the absence of the owner and requires repair. The annual route across the Pacific Ocean looks like a giant loop 20-25 thousand km long. It can apparently be considered that the slender-billed petrel is one of the most advanced flying creatures that ever lived on Earth.
The routes of sea migratory birds cover all the oceans in a gigantic network, occupying about 70% of the surface of our planet. But there are birds that fly mainly over land.
Across countries and continents
Among the “land” flyers there are also record holders. One of them is called a sandpiper. He received his nickname because the male, participating in mating games, inflates his neck and emits a dull trumpet. The pouting sandpiper nests in the Arctic tundra of Canada, Alaska and Siberia. Its flight route - 14-15 thousand km - passes over the great plains of North America, through Mexico, the countries of Central America and ends in the south of the South American continent.
There are other wonderful fliers in the shorebird family. For example, the brown-winged plover, nesting in the Canadian tundra. After taking off, the plovers fly southeast and soon find themselves over the cold waters of the North Atlantic, near Labrador, Newfoundland and Nova Scotia. Plovers are saved by their extraordinary endurance, because they cannot land on water. The plovers make a three-day rush across the ocean, covering almost 4 thousand kilometers without landing during this time. km. True, some birds take a break in the Bahamas and Antilles, but the majority do not stop in flight, reaching the green shores of Venezuela or Guiana.
Of the record holders for migratory flights over land, it is worth mentioning some species of swallows nesting in Northern and Central Europe and Scandinavia. They lay their 13 thousand km long routes across Europe and Africa.
Good fliers, the mute swan and whooper swan, nesting in remote places of Northern Europe and Asia, fly to the Mediterranean, Iran, Afghanistan, South and Southeast Asia for the winter, and in the spring they are among the first to appear in their native places. Gray cranes are not far behind them. These birds carefully prepare for a difficult flight, make test flights, practice coherence and rhythm of movement, select flocks, and train young birds. Rhythmically flapping their wide wings, the cranes fly in a wedge. Some head to Africa and, following along the Nile, reach Sudan, others cross Iran and stop on the shores of the Persian Gulf, others from Siberia end up in India and Southwestern China, but in all cases they fly 7-10 thousand km from home .
By September, white storks also set off. Their routes, covered mainly by gliding flight, lie over land. Storks cross bodies of water only when the opposite shore is visible.
If storks nest in Europe west of the Elbe, then the flock flies to Gibraltar. To cross the narrowest, 16-kilometer-long part of the Strait of Gibraltar, the birds gain high altitude over Spain and begin to glide to Africa, using air currents and rising heat flows. Some birds remain in the west of the continent, while others overcome the largest desert in the world - the Sahara. Further, deviating to the southeast and then to the south, the storks cross a strip of equatorial forests. Having flown almost three quarters of the African continent, they finish in South Africa, leaving 12-13 thousand km behind.
If storks nest east of the Elbe, then the flocks head to the Bosphorus, go around the Mediterranean Sea from the east, fly over Palestine, Egypt, along the Nile Valley and arrive in South Africa, covering the same 12-13 thousand km.
It is worth mentioning the birds that set flight altitude records. These are undoubtedly gray geese, which were seen at an altitude of 8850 and even 9100 m above the highest mountains on the planet - the Himalayas. At such altitudes, even trained climbers need oxygen apparatus, and acclimatization is necessary before climbing. This does not apply to geese. In flight, they can be content with a small amount of oxygen for at least one and a half to two days and not lose their performance.
This incredible flight across the Himalayas looks something like this. In autumn, flocks of gray geese gather in southern Siberia, rest and feed before migrating. One day at dawn they take off, gain maximum altitude and head towards giant mountains, shining with glaciers and snowy peaks. At the head of the flock, moving in a wedge, flies an experienced leader who knows all the saddles and passes between the mountains. Birds spend many hours in 40-degree frost. Finally, the eight-thousander peaks are left behind. Another two to three hours of flight, and the hills and forests of Northern India appear below. The leader chooses a place to rest, and the mortally tired birds land on a small island in the middle of a secluded lake.
Such height records are, perhaps, only possible for geese and, perhaps, choughs. Most birds fly at an altitude of about 1500 m. On clear nights they can rise even up to 6 thousand meters.
According to some scientists, approximately 30% of birds that fly away for the winter return to their nesting sites. The rest die due to sudden changes in weather, storms, winds, frosts, lack of strength and other difficulties. But every year in the fall, instinct removes millions of birds from their homes, and they fly away along their own, often incredibly long, routes in order to survive the winter, return again and give birth to offspring that will exactly repeat the path of their parents.
This small white bird with a black “cap” on its head holds the record for the longest migratory route. In order to overwinter, it flies from the Arctic to Antarctica, and returns back in the spring. During the year, the Arctic tern flies an average of about 70,000 km, and some individuals manage to fly more than 80,000 km. Considering that the length of the equator is just over 40,000 km, it turns out that the tern’s flight from pole to pole 2 times a year is equal to completely circling the entire globe.
Children raised by animals
10 mysteries of the world that science has finally revealed 2,500-Year-Old Scientific Mystery: Why We Yawn Miracle China: peas that can suppress appetite for several days In Brazil, a live fish more than a meter long was pulled out of a patient The elusive Afghan "vampire deer" 6 objective reasons not to be afraid of germs
This small white bird with a black “cap” on its head holds the record for the longest migratory route. In order to overwinter, it flies from the Arctic to Antarctica, and returns back in the spring. During the year, the Arctic tern flies an average of about 70,000 km, and some individuals manage to fly more than 80,000 km. Considering that the length of the equator is just over 40,000 km, it turns out that the tern’s flight from pole to pole 2 times a year is equal to completely circling the entire globe.
Arctic tern
The Arctic tern forms a separate species in the tern family and is a native inhabitant of the cold Arctic lands. It nests in the northern lands of Canada, Alaska, along the entire coast of Greenland, Scandinavia and the tundra zone of Russia from the Kola Peninsula to Chukotka. When cold autumn sets in in the Arctic, the bird heads south. It spends almost all its time above the surface of the sea and moves south and south until it reaches the eternal ice of Antarctica. It's summer in the southern hemisphere at this time, and the little bird is the only creature on the planet that sees summer twice a year.
Arctic tern sitting on the snow
The bird flies 19 thousand kilometers one way. In total, in a year it covers more than 80 thousand kilometers. The lifespan of this species is on average 20 years. During this period, individual birds cover 2.4 million km. No other bird can boast of such distances.
You can give an example. In the summer of 1982, the chick was ringed on the Labrador Peninsula (Canada). In October of the same year, he was discovered in Australia near Melbourne. At the same time, the young bird covered 22 thousand km. Another pilgrim, also ringed in Labrador, was found 4 months later in South Africa. From this it can be seen that the Arctic tern travels all over the world, and distances are not an obstacle for it. But in the spring the bird invariably returns to the northern tundra and begins to breed.
Appearance
This bird is very similar to a seagull, but its body is shorter and its wings are longer. The length of the body from the tip of the tail to the tip of the beak reaches 33-40 cm. The wingspan is 74-85 cm. Weight ranges from 90 to 130 grams. Visually, the bird appears large due to its long wings. The top of the head is black. The plumage on the body is white. There is a light gray coating on the chest, outer side of the wings and back.
The tail is white above, light gray below. The beak is dark red, the legs are short, and the feet are webbed. The tail is fork-shaped. Males and females are no different in appearance. In winter, the bird's forehead turns white. Juveniles in the first year of life have a brownish-motley coating on the back, and the length of the tail is shorter than that of adult birds. In the second year, all age-related features disappear.
Reproduction and lifespan
The Arctic Tern arrives in its native Arctic tundra after long journeys in the midst of spring. This bird adheres to monogamous relationships, so the pair is formed for life. Courtship is accompanied by “dancing” in the air, while the male gives the lady of his heart a small fish. If she accepts the gift, the birds begin to fly together and make various crackling sounds.
The nest is usually made on the shore of a pond. In summer there are many lakes in the tundra, and birds settle near them. But they prefer small islands surrounded on all sides by water. Several pairs usually live on the islands. They form a small friendly colony. Conflicts among terns almost never arise. The nest is very primitive. The female rakes up grass or moss and lays eggs in this depression. There are usually 2 or 3 of them. Both the female and the male take part in incubation. The incubation period lasts 22-27 days.
These birds are very brave. In case of danger, they fearlessly attack birds of prey, arctic foxes, and humans. At the same time, they use their strong beak. His blow is very noticeable. Therefore, people should not go close to the nests of these aggressive birds without a hat, as they can be seriously injured. This fearlessness attracts shorebirds, ducks and other peaceful birds. They try to nest next to terns, as they scare away all the predators around.
Chicks hatched from eggs are covered with down. After just a couple of days, they begin to actively explore the nearby territory, but do not move away from the nest. In case of danger, they run away and hide behind hummocks or in the grass. Parents feed their babies for a month.
Behavior and nutrition
During migrations, the Arctic tern feeds on fish, krill, mollusks and crustaceans. It hovers above the sea surface at a height of 10-12 meters and looks out for prey. Dives perfectly, but to shallow depths. During the nesting period, it is content with water insects, larvae, and small fish. It usually does not exceed 5 cm in length. It pecks at berries from plant foods.
Number
In general, the number of the species is at a stable level. According to experts, there are at least 1 million Arctic terns living in the world today. But birds are dispersed over a vast territory, covering almost the entire globe. Even during the nesting period, they spread over a very large area. Therefore, this million does not catch the eye. The colonies are small and located at a decent distance from each other. In former times, bird feathers were used to make ladies' hats, so terns were caught. Nowadays, this species has no commercial value.
