The South Pole Skua belongs to the genus Great Skuas. This seabird is quite widespread in the vastness of Antarctica and adjacent islands.
The birds make winter transequatorial migrations, reaching the shores of Alaska and Greenland. The South Pole Skua is the only bird known to fly deep into Antarctica, reaching the South Pole. During the northern summer, South Polar Skuas molt. As a rule, molt does not coincide with the nesting period.
South Pole Skua breeds in Antarctica and adjacent islands. Males first go to nesting sites and only then females. Pairs of skuas form once and for life. Birds nest in small colonies, each consisting of several dozen birds. Outside the nesting season, the bird is constantly in the open sea.
As a rule, birds use the same nesting territories for several years, while the very location of the nest may change. The nest of the South Pole Skua is a common pit in rocky areas, most often without any litter.
Skua bird. Skua lifestyle and habitat
The first chicks begin to appear in the second decade of January. They are small downy lumps, the weight of which barely reaches 70 grams. The younger generation grows up and matures for two months. After this period, the chicks stand on the wing and begin an independent life.
Sexual maturity in skuas occurs at the age of 6, sometimes 7 years. The life span of this bird is 40 years.
Family Skuas / Stercoraridae
Skuas are primitive gulls. They are similar to real gulls, but differ from them in a darker color of plumage, weak legs, a stronger beak and a pointed tail. Gulls have a rounded tail, while skuas have an elongated middle tail pair. In some species of skuas, some of the individuals are colored in light colors, and some in dark ones (morphism). Moreover, one nesting pair can be differently colored individuals. Skuas nest on the coasts in the highest latitudes of both hemispheres, but in the post-nesting time they can be found in the seas up to the equator and in the interior of the continents. Skuas are more predators than other gulls. In the arctic tundra, they feed largely on lemmings. Nests are often built near seabird colonies, where their eggs and chicks are stolen. But they are even more characterized by kleptoparasitism - taking away prey in the air from other seabirds, which they actively attack. In our north they are therefore called "soldiers." There are 5 skuas in total, making up 2 GROUPS - major and minor skuas.
This bird nests in colonies, less often in separate pairs. The nest is usually in the form of a small depression in the soil among dry grass. In birds of the North Atlantic, eggs are laid in late May - early June. In clutch there are 2, less often 1 egg of variegated color. Both members of the pair incubate for 28-30 days, apparently starting after the first egg has been laid. Chicks stay in the nest for about 6-7 days. When the first masonry is ruined, there is an additional one. The Greater Skua is primarily a carnivorous bird. It, like other species of skuas, is characterized by a parasitic way of feeding: taking away prey from other seabirds. Along with this, he obtains food and his own means. A significant place in the diet of the described species is occupied by fish, mainly taken away from gulls, terns and gannets. Invertebrates are eaten in some quantity. It also feeds on eggs, chicks and adults of seabirds, small mammals, and various garbage, in particular from whale fishing.
western hemispheres. In some places it enters the forest-tundra. Migrant. Winters in the Mediterranean, in the region of Japan, Chile, Peru and Argentina, mainly in the open parts of the ocean. Skuas arrive from wintering grounds to nesting sites in springtime - at the end of May or June. Soon one can observe their characteristic games in the air, accompanied by gusty throws or lightning-fast flight, as well as various cries, most often similar to a dog barking. After a while, the birds start nesting. They nest in separate pairs, at a considerable distance from each other, and only in places - in colonies. Nests are made on dry soil in the form of a hole without any lining. As it incubates, a lining of lichens appears in the nest. Depending on the geographic location of the area, eggs are laid on different dates in June and in the first half of July. In a clutch there are 2, sometimes 1 or 3 eggs of olive or greenish-brown color with rare dark-brown streaks, mainly at the blunt end. Egg sizes: 50-60 X x37-42 mm. Incubation begins after the first egg is laid, so the chicks in the brood are of different ages. Both parents incubate for 23 days. The bird, free from incubation, guards the nest, sitting somewhere nearby on a hillock or hummock. Old birds actively protect clutch and chicks. Chicks hatch at different dates of July and grow rather quickly. At three weeks of age, they are fully fledged, but long before that they get out of the nest. In August, juveniles rise on the wing, and if food reserves in the area have dried up, then by the end of August skuas fly away. Molting, like other skuas, occurs mainly during wintering. The food of the Long-tailed Skua is very diverse: small fish, rodents, small birds and chicks, insects and their larvae, crustaceans, molluscs, worms, berries and garbage. In spring, the most important berries are crowberry, lingonberry, bearberry, during the nesting period - rodents (lemmings, voles) and even weasels. In years poor in rodents, skuas feed mainly on small birds - Lapland plantains, waders, their chicks and eggs. In the fall, before departure, berries occupy a large share in the diet. The described species uses less food taken from other birds than other skuas, therefore, more depends on the prey caught by itself. This dependence on murine rodents, and primarily on lemmings, is especially significant. In years poor in lemmings, the number of birds decreases sharply, and nests are not observed in such years. On the contrary, with an abundance of lemmings, the number of skuas increases dramatically and all of them usually participate in breeding. The skua's need for food can be judged by the following example: one bird eats 3-4 lemmings per day.
The bird's body length is 55 cm.
This is 10 cm less than that of the Great Skua, which lives in the Northern Hemisphere and is a regular in the lands adjacent to the Arctic.
The wingspan of the South Pole Skua reaches 135 cm. The beak is strong, with sharp edges, curved at the end. The color of the feathers is either dark or almost black with a brownish tint. There are birds that have a gray chest and head, and a dark brown upper body.
Some representatives of this species have a yellow-brown belly. Chicks, as a rule, are bluish-gray, rarely have a faint yellowish tint on the back. Molting takes place in the summer.
Reproduction and life expectancy
Skua nests directly on the icy continent or on nearby islands. His favorite spots: South Shetland Islands, South Orkney Islands, he also loves the Ross Sea coast, where bedrocks come to the surface.
The bird also likes the coast of Queen Maud Land - especially the coast of Princess Ragnhill. He also does not refuse the coastline of Princess Martha.
Males first flock to nesting sites, and only then females are pulled up. Monogamous skua. Pairs are formed once and for all. Therefore, only young people are engaged in mating games. She gathers away from nesting sites and is divided into pairs.
Nesting sites are colonies of several dozen birds. The pairs are spaced from each other at a distance of 20-30 meters. Much is done right in the ground, where a small hole is cleared.
The female begins to lay eggs in late November.
This continues throughout December. There are always two eggs, they are born with an interval of two days. The incubation period lasts a month. The female and the male hatch eggs in turn.
Behavior and nutrition
After nesting, the skua begins the wintering period. He begins to migrate from the colonies in March. This continues throughout April. The bird flies to the north. It crosses the equator and finds itself in the summer zone.
Here she is looking for cooler places, and therefore spends long six months in the northern parts of the Atlantic and Pacific oceans. The skua visits Newfoundland, the Kuriles, and other areas in these latitudes.
Some birds hibernate closer to their dear Antarctica. They fly only to the south of Africa, or rather to the tropics of Capricorn. In these places they wait for spring to come in the far south. The skua feeds on fish, but he himself cannot catch it, since he cannot dive. Therefore, he takes fish from other birds or catches the one that swims near the surface of the sea.
Skuas are close to seagulls, but are easily distinguished from them by their dark plumage.
Some species have two color variations - dark, in which the whole bird is dark brown, and light - with this variation, the belly and chest of the bird are white with an ocher tint. Another striking feature of most skuas is the highly elongated central tail feathers.
Long-tailed Skua the smallest of the skuas and the most widespread.
In Russia, it breeds along the entire Arctic coast and adjacent tundra from the Kola Peninsula to Chukotka, Kamchatka and the western coast of the Sea of Okhotsk. Some of the Arctic islands do not have these birds.
The Long-tailed Skua is about the size of a common gull, weighing 274.5-297.3 g. The female is somewhat heavier than the male. An adult bird is easily distinguished from other skuas by its smaller size and very long central tail feathers, reaching 31 cm and protruding far beyond the other tail feathers.
This skua has no dark color variation.
Short-tailed Skua the size of a blue-gray gull. Its length is about 45 cm, the wingspan is about 105 cm, the mass of males is 429, females are 462 g. This species is dimorphic, some of the birds are entirely dark, and some are light-bellied. At the same time, different color morphs often make up nesting pairs.
Central tail feathers are slightly longer than the rest of the tail feathers.
Pomarine Skua even larger, noticeably larger than the gray gull, but much smaller than the herring gull.
Its length is about 53 cm, wingspan is about 135 cm, weight is 631-687 g. It also has 2 color morphs - dark and light-bellied. The middle pair of tail feathers is significantly elongated, while at the end the feathers are peculiarly inverted, so that in a flying bird they seem to be strongly expanded.
Great Skua the size of a herring gull, dark brown in color, with a white mirror on the wing.
Central tail feathers only slightly protrude beyond the cut of the rounded tail. It is considered a stray species, although when I visited Novaya Zemlya in the summer of 1999, I met the Great Skua on several occasions. It is possible that a small number of these birds nest here.
The diet of skuas, like almost all gull birds, is quite varied. They eat fish, various invertebrates.
They feed on the waste of fish and animal hunting and the corpses of animals thrown out by the sea. Landfills are not visited. Small rodents, especially lemmings, play an important role in the diet of these birds. Sometimes the successful breeding of skuas is associated with the abundance of these rodents.
The common skua swallows whole lemmings. He also arranges food supplies near the nest (up to a dozen dead animals were found in them). All skuas are characterized by kleptoparasitism. They attack auks, terns and gulls in the air, forcing them to abandon their prey or regurgitate food that has already been swallowed. However, larger species of skuas are more likely to pirate.
The Arctic Skua decides to take away prey even from the Herring Gull, which is much larger and rather aggressive. And the great skua also attacks the gannets, attacks the birds if they are weak or sick.
Among its victims were coots, medium curlews, various gulls, including herring gulls.
All skuas destroy birds' nests, the short-tailed, for example, can destroy the nests of both eiders and herring gulls. The shells of the eggs taken from the nest, according to my observations, they do not peck, as crows, magpies and even many seagulls do, but breaks into pieces. However, whether all skuas and whether they always do this, I can not say. After all, it is not often near the shells of eggs killed by a predator that you find paw prints of a robber.
Since skuas live mainly in the tundra, no trace of them remains on moss and bumps. It is easier to find them on the sandy shoals of tundra rivers or on damp areas of soil where there is no turf, less often paw prints come across on a sandy seashore.
Paw prints of a Arctic Skua perched on a sandbank
Skuas of all species are similar in size but differ in size.
Who is the skua bird: features and habitat
The back finger is not imprinted on the tracks. The membrane is wide and does not have a concavity on the tracks, like in gulls. The claws protrude noticeably beyond the edge of the membrane, especially on the middle toe, which makes the print appear somewhat pointed. In general, skuas tracks can be distinguished from tracks of ducks of similar size, and from tracks of gulls.
The paw print of the Long-tailed Skua is 4 × 4 cm, somewhat smaller than that of the common gull and whistle teal.
The short-tailed skua leaves an imprint of 4.4 × 4.4 cm. The stride length is 8-12 cm, the track width is about 6.8 cm. The width of a pair of prints of a sitting bird is slightly more than 10 cm. The paw print of the common skua is about 6 × 6 cm. Unfortunately, I did not find a Great Skua. Apparently, they differ little in character from the tracks of other skuas, but in size they should be much larger than them, approximately like the tracks of a herring gull.
The lower surface of the paws of skuas: long-tailed (a), short-tailed (b) and middle (c)
Eating a variety of foods, skuas are forced to drop pellets, but the researcher rarely comes across them.
Found pellets very often contain shiksha seeds, and sometimes consist only of them. Apparently, this berry in certain seasons plays an important role in the nutrition of various species of skuas.
(By the way, the fruits of shiksha are eagerly eaten not only by birds, but also by many northern animals - minks, martens, arctic foxes, preferring them to blueberries and other berries.) The size of the short-tailed skua is 1.7 × 1.1 cm, the average is about 3 × 2, 5 cm.
Skuas' droppings are denser than those of gulls. Semi-liquid dark "sausages" are visible in the middle of the white spot. In the Arctic Skua, the “portion” of the droppings spreads over an area of 4 × 4 cm.
These birds nest in the tundra. Eggs are laid in a hole among moss or lichens.
In clutch there are most often 2 eggs of dark olive-brown color with even darker spots. In the long-tailed skua, the egg size is about 5.6 × 4 cm, in the short-tailed skua - 5.8 × 4.1, in the middle skua - 6.4 × 4.5 cm.
As you can see, the differences in size are small, so if there are no owners near the nest, it is rather difficult to find out which species of skuas the nest found belongs to.
Skuas in the Collegiate Dictionary:
Skuas are a family of birds of the order Charadriiformes.
Length 45-60 cm.4 species: the Greater Skua is bipolar, others in the Arctic and Subarctic. They usually nest along the shores of the seas.
The meaning of the word Skuas according to the Brockhaus and Efron dictionary:
Skuas (Stercorarius) is a genus of birds similar in general body shape to gulls and attributed to the same long-winged order (see Swimming birds) as gulls. P., or "predatory" gulls, differ from real gulls by the structure of the beak and legs and the way of life.
The beak is shorter than the head, the top of the beak is bent in the form of a strong hook from top to bottom, and the main half of the beak is covered, as it were, by a keratinized beak. The short toes of low feet are connected by a full swimming membrane and are armed with strongly curved sharp claws. The two middle tail feathers of the twelve-stepped tail are always more or less protruding from the rest.
The predominant color of plumage is dark brown, darker in older birds. P.'s voice is an unpleasant croak. P. live mainly in the northern cold zone, in the open seas, visiting the coast only during the nesting period. At this time, P. gather in small flocks and take the children out together. For the nest, a simple hole is dug in the sand or ground, where 2 - 3 usually olive with dark spots are placed, hatched alternately by the male and the female.
Although P. keep well on the ground and can run quite fast, they spend most of their life on the water or in the air. P. feed mainly on fish, although they rarely catch it themselves, since they dive poorly: they usually take it away from gulls, terns and other birds, which they constantly watch. P. also attack weaker birds and small mammals, like true birds of prey.
Finally, they also feed on various invertebrates. Of P., the most common types are: P. short-tailed (St. crepidatus) and P. long-tailed (St. parasiticus), known in the North. under the names of "police officer", "closer", "robber" or "crowbar".
Both species are circular polar birds. The long-tailed P. differs from the short-tailed in longer middle tail feathers, gray with black spots, and not monochrome black, as in the short-tailed P., in legs, white trunks only in the first two (and not all) flight feathers and a large distance from the nostrils from the tops of the beak.
The usual coloration of an adult short-tailed P. is monotonously chestnut-brown, but a short-tailed P. with a white chest and neck and an almost gray back, which in their coloration are very similar to long-tailed P. Both species, are distinguished by fast, skillful flight and courage.
The long-tailed P. is a more predatory bird than the short-tailed. Yu. Wagner.
The definition of the word "Skuas" by TSB:
Skuas (Stercorariidae) are a family of birds of the order Charadriiformes, related to seagulls.
Body length 45-60 cm. The horn cover of the beak consists of separate scutes. The middle tail feathers are elongated. P. of the same type can be monochromatic brown or with a light belly. 2 genera: Stercorarius (3 species - medium, short-tailed and long-tailed P.), distributed circularly in the Arctic and Subarctic (in winter - in tropical waters), and Catharacta (1 species - large P.), widespread bipolar - in Iceland, in the Faroe Islands, in the north of Scotland and from 40 ° S. sh. to Antarctica.
P. live in the tundra, more often on the sea coasts. There are 2 eggs in a clutch, they incubate for 28-30 days, chicks begin to fly on the 30-40th day. They feed on fish (often taking it away from gulls, guillemots, and other birds), as well as invertebrates, rodents, and berries, and destroy the nests of other birds. Long-tailed Skua: 1 adult, 2 young.
America, off the southeastern coasts of Australia, off New Zealand, in the Persian Gulf and off the coasts of Pakistan. Occasionally found inside the continents. In terms of lifestyle and habits, it has many similarities with other skuas.
Middle Skua / Stercorarius pomarinus
Migrant. During migrations, it moves mainly along the oceanic coasts, descending south to Japan and California on the Pacific Ocean, to Central America and Africa on the Atlantic. Pomarine Skua nests in the tundra, near sea coasts or inland waters. The nest is usually placed on a hummock and is a small depression in the soil lined with lichens, dry grass, and willow leaves. Sometimes eggs are laid simply on the soil. In clutch there are usually 2 brownish eggs with dark spots and streaks, laid in different dates of June. Eggs are laid 48 hours apart. The male and the female incubate for a little less than a month, starting from the laying of the first egg. When approaching the nest of the enemy, they very zealously attack him and drive him away. Downy chicks were observed in July, flying ones - in August. Young people very soon begin to lead an independent life. There are observations that this bird does not nest in years of low lemming abundance. Departure takes place in September - October. Molting begins in August with a change of small plumage and ends in February - March at wintering grounds. The premarital molt also occurs there in February - April. The Pomarine Skua feeds on a wide variety of animals - fish, invertebrates, lemmings, small birds and their eggs, and various garbage. He swallows lemmigov whole, and the nests have stocks of captured animals (up to 10 or more individuals). A large place in the diet of this species is taken by food taken from gulls, terns and other birds. Pompous skua closely follows the birds flying by and if it sees prey in their beak, it pursues them until they release it from the beak. Often he manages to grab a fish thrown out by a seagull before it falls into the water. Vegetable food is also of little importance in the diet of the skua.
Researchers have noted an important behavior characteristic of these Antarctic birds. Skuas were christened pirate birds for a reason.
They are cunning, smart, quick-witted, have an excellent memory. These qualities help in the struggle for survival.
Skuas not only brazenly rob their neighbors, taking away their food, but often encroach on human prey.
Skuas are omnivorous predators. They are happy to feast on eggs, small rodents, chicks of birds living in the neighborhood. Gulls, puffins and penguins especially suffer from them, which skuas terrorize mercilessly, destroying nests and abducting young animals. Scientists have documented several cases of cannibalism.
These birds are very fond of fish, but the fishermen of them are simply useless - they cannot dive. But they can simply rob a more successful neighbor along the coast, taking away his catch. Often, a raider seizure takes place right in the air: upon seeing a bird with prey in its beak, a skua attacks it and grabs the repulsed fish right on the fly. Strength, determination and massive build - what else is needed for this kind of racketeering?
Skuas are very attracted by seaports, fish factories, fur farms, and fishing vessels. These birds are not too shy and are used to the fact that people do not offend them. They are especially attracted by the heaps of industrial and farm waste.
In general, bird watchers have long noticed that these quick-witted birds always choose the easiest way to get food. If flying fish live nearby, skuas focus on them, dashingly hunting for those jumping out of the water. In favorable years for rodents, when their populations are growing, skuas can generally leave their neighbors and ocean inhabitants alone, completely switching to small animals. And if there are food processing facilities nearby to profit from, skuas stop hunting and are content with waste.
The Great Skua (Latin Catharacta skua) is a seabird belonging to the Skuas (Stercorariidae) family of the Charadriiformes order.
He is the largest representative of its kind.
This bird is very strong and dexterous; it loves to attack other birds and take prey from them. Even adult emperor penguins and gape fishermen are not immune from her attacks.
The habitat of the Greater Skua covers the whole of Antarctica, the islands and coastal areas of Great Britain and Iceland, as well as part of the territory of the Scandinavian countries.
The European population numbers about 35 thousand individuals, of which about 20 thousand prefer to nest off the coast of foggy Albion.