Polar habitat: Polar habitats | TheSchoolRun

Snowy Owl Head is wide and round, there are almost imperceptible small ears, which, however, does not interfere with hearing their prey at all even at great distances (these owls are able to pick up sound with a frequency of 2 Hz). This bird can turn its head 270 degrees, allowing it to view in three dimensions.

The eyes of this bird are also round, always yellow, although the shade itself may vary. Snowy owls have very sharp eyesight, they see 4 times better than cats and 10 times better than humans. Thanks to this vision, these birds can successfully hunt even in very low light. Ornithologists conducted an experiment that brought amazing results: a snowy owl was able to find its prey, which was 350 m away from it, while there was no light in the room, only an ordinary candle was burning weakly. Here one can easily conclude that it is not difficult for this bird to hunt even in the conditions of the polar night.

The snowy owl can give a voice: its cry is like a staccato croak, sometimes resembling a bark. The sound itself is sharp and loud.

The Snowy Owl sheds twice a year shedding her old plumage in early summer and late autumn. By the end of November, it is completely covered with new white feathers. Young chicks acquire their first feathers around the end of September or early October.

The lifespan of such a bird depends entirely on its habitat, for example, in the wild northern nature, it lives for about 10 years. In captivity, for example, in nurseries and zoos, snowy owls can live up to 30 years.

Habitat

Such a bird lives in the arctic zones of both hemispheres of the planet Earth, in addition, it can often be found in the tundra of Eurasia and North America, as well as in Greenland, on the island of Bering, Novaya Zemlya, Wrangel, Kolguev and others Arctic territories. For wintering, these birds choose open areas near the zone of deciduous forests; they very rarely fly into populated areas. The entire wintering period lasts from late September to early March, and in the spring the owls return to the Arctic to breed chicks.

The snowy owl is a sedentary bird, but sometimes it can be nomadic if the number of prey in its habitat decreases or the thickness of the snow cover exceeds the allowable limits.

Hunting

The bird hunts mainly lemmings , which are rodents from the hamster family, as well as hares, fox cubs, hedgehogs and stoats. Often, snowy owls prey on other northern birds, do not disdain seafood and sometimes even carrion.

These birds never hunt near their nests, flying away for prey at decent distances. An adult bird requires an average of 4 rodents per day.

This northern bird menacingly protects its nest within a radius of 1 km , and, by the way, that is why gulls build their nests next to it, which feel completely safe next to owls.

The process of hunting is as follows: a bird stalks its prey in the open area, soaring in the sky, then stalks it and dives and grabs the prey with its sharp claws.

How snowy owls breed and nest

As mentioned above, in this species, the mating season begins in early spring, in March, when they return from wintering. Males occupy the territory they like and begin to announce it with a loud cry. D a series of active actions follow:

• they scare away all rivals, sometimes engaging in battles with each other;
• in order to attract a female, the male can arrange small races for short distances, running across the mounds and periodically singing;
• if the female pays attention to him, he begins to ruffle and stomp around her, or makes a sharp flapping of his wings up and down;
• he also presents the female rodent as a gift, after which they form a pair and begin to guard the territory together.

These birds create permanent pairs, hatching chicks every year, but sometimes they meet for only one year. Nests are arranged on small hills and hills, but sometimes they can choose lowlands. The nest itself is a small depression, the bottom of which is covered with moss, dry grass and bird fluff.

The female lays up to 8 eggs , incubating them for 1 month, while the male himself hunts and gets food. Owlets hatch gradually, one after another, but, as a rule, the youngest often die. When all the chicks hatch, the female herself begins to fly out to hunt, while her offspring bask in the nest, tightly clinging to each other. After 50 days, they can already fly independently.

Snowy owl population

These birds represent a small population, they mainly live on Wrangel Island. Birds are of great importance for nature as they support a stable population of northern rodents and provide security to other birds, protecting the territory from predators.

Arctic tern — description, habitat, interesting facts

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In the cold Arctic territories, life also exists, and many representatives of the fauna are very comfortable there. Here, polar terns have found a haven, classified as a tern family because of the straight and long beak with a hooked tip. And they do well in cold weather.

Appearance

If it weren’t for the shorter body and longer wings, the Arctic tern could have been mistaken for a gull. The body length is from 35 to 42 cm, the bird weighs from 90 to 130 grams, its wingspan is from 74 to 84 cm. Since the wings are elongated, it seems that the bird is much longer.

It is easy to recognize the Arctic Tern thanks to the contrasting plumage: the body is snow-white, only the breast, back and wings are noticeably darker in shades. The tail is also white above and grayish below, forked. The head is conspicuous — with a black cap. However, in winter, the forehead becomes completely white. The frontal plumage reaches the nostrils. The beak, evenly colored, adorns the bird of a red dark color. The head has an angular shape.

The legs are short and webbed between the toes. The gait of the Arctic tern is different in that it waddles because of its short legs.

Male and female are very similar in size and color. They do not have sexual dimorphism. But the young are easily distinguishable, since in the first year of life:

• the back is colored in brown variegated shades;
• is much shorter tail.

In the second year, these differences disappear, and the grown-up chicks are no different from their parents.

Birds have a very sharp voice, distinguished by shrillness.

Nutrition Features

When it’s time to eat, a hungry tern soars up and soars at a height within 10 meters above the water, sometimes dropping lower. All her attention is concentrated in search of prey, and she has the ability to hover in one place, supporting herself with quick flapping of her wings. Having noticed the target, the bird rushes down with a sharp movement, catching prey. This roll represents a diving flight. But sometimes such manipulations have to be performed several times, often up to three attempts, and the tern can also pursue the victim under water, as it dives beautifully, but not to very great depths.

Like other inhabitants of the coastal zone, terns watch other birds when they are hunting and find schools of small fish. Taking advantage of someone else’s powers of observation, the tern starts hunting in this place.

It feeds on small fish and krill, crustaceans, worms and molluscs. But, if shrubs with berries grow on the shore, terns do not refuse them either.

When the nesting season comes, the diet changes slightly, terns eat aquatic insects and larvae. But don’t forget about the fish.

Travel Lovers

Arctic terns are not lazy to travel, overcoming thousands of kilometers. They build nests in the northern hemisphere, closer to the North Pole. Most often these are northern Canadian regions, Scandinavian countries, Russian tundra regions. But for wintering, as soon as cold autumn begins in the Arctic, they go to the South Pole, to the Antarctic region and nearby islands. It so happens that often these small fearless birds overcome a distance that is estimated at up to 80 thousand km! This journey takes more than a month. But all these tiring movements are not in vain, because the terns live in a summer climate for a whole year.

Brethren of the Arctic Tern

The Arctic tern has numerous relatives that belong to the tern family. Some of them:

1. River. Less polar, with a black mark at the end of the red beak. The legs are red, the tail is forked. Habitats — the seas and reservoirs of the European zones. Places of migration — West Africa, South America.
2. Light. Their head and neck are white, the back of the head is black, and a dark stripe runs through the eyes. The paws and beak are also black, but it has a yellow top. In the younger generation, a black spot is visible in the back of the head, and spots with gray-brown hues adorn the head. The beak and legs are yellow, but the legs are darker. They live in tropical climates near the Indian Ocean, as well as in Australia and the Pacific Islands.
3. Pink. The main difference is a pinkish or orange beak. You can meet them on the islands and coasts of African and European, American and Southeast Asian.
4. South American — have a red beak and paws, brown paws in chicks. Weight can reach 200 gr.
5. Antarctic. Differ in small size, the beak is not always red, it can be black.
6. Indian. Prefer to live near fresh water. The back of them is dark gray, the tail is forked, but cut deep enough. The wings are pointed and long, with a black mask over the eyes. The beak is yellow, but its base is grey. Paws are red.
7. Small. Their weight does not exceed 45 gr. The paws are yellow, the beak too, but with a black end. There are white stripes above the eyebrows. Their nesting is sandy banks, shallow rivers with the presence of gravel.
8. Variegated. Differ in a long and thin beak, which is painted black. Its tip is light yellow.
9. Bengal. The back of this species is dark gray, the beak is sharp and thin, has a rich orange color. Juveniles have an orange-yellow beak and brown-gray paws. Growing up, the paws of this tern turn black.

Family relations

Arctic terns find a mate to be together all their lives. But first, the male has a responsible task: he must attract the female by courting her. To do this, in the air, the groom shows skill in dancing, and then treats the chosen one with a fish. As soon as the female accepts such a gift, the couple reunites, flies together, making joyful sounds resembling a rattle.

Then it’s time to build the nest. A place for it is chosen on the banks of reservoirs, most often these are small islands, so that there is water on all sides. It is customary for Arctic terns to settle in small colonies. These communities are very friendly, there are practically no quarrels and conflicts between them.

Parents do not make any special efforts to create a nest. Just a female in May rakes the soil between grass and moss in a selected place. Eggs are laid in the resulting hole. Usually there are two or three. Both parents take part in incubation. This period lasts for about 22 — 27 days. There is one laying per year.

Newly hatched chicks are covered with soft fluff. They are so curious that after a few days they begin to move away from the nest for short distances. But in case of danger, they know how to behave, running up in different directions and hiding in the grass. At this moment they do not show signs of life, they wait until the danger has passed.

Parents keep and feed the children for a month, and already 2-month-old chicks are trying to fly. Chicks, like adults, are well adapted to life in severe frosty conditions, as evidenced by statistics. The survival rate of these birds is over 80 percent.

Sexual maturity is reached 3-4 years after birth.

Arctic terns can defend themselves, they fearlessly rush at enemies, and a powerful beak helps them very well in this. If it is necessary to protect the nest, predatory animals and birds may suffer, as well as people — everyone who dared to approach the nesting site. Attacks usually occur from the air, and it is very difficult to escape from a powerful beak. Such courageous behavior leads to the fact that other species of birds try to settle next to the colony of polar terns. First of all, these are ducks and waders, which do not have enough strength and courage to resist offenders.

Life expectancy for these birds is an average of 20 years. But there are cases when the Arctic tern lived up to 35 years of age.