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There is life in the cold arctic territories too, and it is very comfortable for many representatives of the fauna. The terns of the tern have found shelter here, assigned to the tern family because of the straight and long beak, which has a hooked tip. And they are in frosty conditions well.
Appearance
If it were not for a shorter body, and wings are longer, it was possible to take the Arctic tern for a seagull. The length of the body 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 have an elongated shape, it seems that the bird is much longer.
It is easy to recognize the Arctic tern due to the contrasting plumage: the body is snow-white in color, only the breast, the back and the wings of the shades are noticeably darker. The tail is also white on top and grayish below, fork-like. The head is noticeable - with a black cap.However, in winter, the forehead becomes completely white. Frontal plumage reaches the nostrils. It is decorated with a bird of red dark beak, evenly colored. The head has an angular shape.
The legs are short, and there are membranes between the fingers. The gait of the Arctic tern differs in that it walks, waddling, because of short legs.
Male and female are very similar - in size, color. Sexual dimorphism is not inherent in them. But the young are easily distinguishable, since in the first year of life:
- the back is painted in motley brown shades;
- much shorter tail.
In the second year, these differences disappear, and matured chicks are no different from their parents.
The voice of the birds is very sharp, different piercing.
Power Features
Like other inhabitants of the coastal zone, the terns watch other birds when they hunt, and find shoals of small fish. Using someone else's observation, the tern begins to hunt in this place.
As a food, it prefers small fish and krill, crustaceans, worms and mollusks. But if bushes with berries grow on the shore, terns do not refuse them either.
When the nesting period comes, the diet changes slightly, the terns eat aquatic insects and larvae. But do not 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, and Russian tundra regions. But for wintering, as soon as a cold autumn begins in the Arctic, they go to the South Pole, to the region of the Antarctic and the nearby islands.So it turns out that often these small fearless birds travel a distance of up to 80 thousand km! Time this path takes more than a month. But all these tedious movements do not occur in vain, because terns live for a year in a summer climate.
Common Tern Brothers
The polar tern has numerous relatives that belong to the tern family. Some of them:
- River. Less polar, at the end of the red beak there is a black mark. Legs are red, forked tail. Habitat - the sea and the reservoirs of European zones. The places of migration are West Africa, South America.
- Light. Their head and neck are white, the back of the head is black, and a band of dark color passes through the eyes. Black also has paws and a beak, but it has a yellow top. The younger generation has a black spot in the nape area, and specks with gray-brown shades adorn the head. Bill and paws are yellow, but paws are darker. They live in a tropical climate, in the Indian Ocean, as well as in Australia and the Pacific Islands.
- Pink The main difference is the pinkish or orange beak.You can meet them on the islands and coasts of African and European, American and Southeast Asian.
- South American - have a beak and paws of red color, brown in chicks. Weight can reach 200 grams.
- Antarctic. Differ in small size, the beak is not always red, maybe black.
- Indian Prefer to live in fresh water. The back is dark gray, the tail is forked, but cut deep enough. The wings are pointed and long; a black mask is on the eyes. Bill is yellow, but its base is gray. Paws are red.
- Small Their weight does not exceed 45 grams. Paws - yellow, beak, too, but with a black finish. There are white stripes above the eyebrows. Their nesting is sandy shores, shallows of rivers with the presence of gravel.
- Variegated. Differ beak long and thin, which is painted black. Its tip is light yellow.
- Bengal. The back of this species is dark gray, the beak is sharp and thin, has a rich orange color. In young stock, the beak is orange-yellow, and its paws are brown-gray. Growing up, the paws of this tern become black.
Family relationships
Arctic terns find a mate to be together for the rest of their lives. But first, the male is faced with a crucial task: he must attract the female while caring for her. To do this, in the air the bridegroom shows skill in dancing, and then treats the chosen one with a fish. It is worth the female to accept such a gift, as the couple reunites, flies together, making joyful sounds resembling a rattle.
Then it is time to build the nest. A place for him is chosen on the banks of reservoirs, most often these are small islands so that there is water from all sides. It is taken from the Arctic terns to settle in small colonies. These communities are very friendly, quarrels and conflicts between them practically do not exist.
To create a nest parents do not make much effort. Just a female in May rakes the soil between the grass and the moss in the chosen place. In the hole formed eggs are laid. Usually two or three. Both parents take part in brooding. This period lasts for about 22 - 27 days. Occurs one clutch per year.
Appeared chicks are covered with soft down. 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 in different directions and hiding in the grass. They do not show signs of life these minutes, waiting for danger to pass.
Parents feed and feed their children for a month, and already 2-month-old chicks are trying to fly. Chicks, like adults, are well adapted to life in harsh frosty conditions, as evidenced by statistics. The survival rate of these birds is more than 80 percent.
Sexual maturity reaches 3 - 4 years after birth.
The average lifespan for these birds is 20 years.But there are cases when the Arctic tern lived to be 35 years old.
In Scotland, there are several wildlife terns for Arctic Terns, although today there are no threats to their numbers, and the population remains stable, with more than 1 million individuals. Scientists observe these birds, and note that they are dispersed in large areas around the world, and small bird colonies can be found everywhere.
Once the Arctic terns were actively trapped in order to get their beautiful plumage to adorn ladies' hats. But gradually this fishery became unclaimed, and the birds were left alone.
Video: Arctic tern (Sterna paradisaea)
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