The predatory fauna of the Far East is not only Amur tigers, Far Eastern leopards and Kamchatka bears. Fans of tickling the nerves of local residents are also found among the "celestials".
The genus of Eagles unites large predators, and the white-shouldered one is the largest among them. The total body length reaches 112 cm, the weight of large females can be 9 kg, and the wingspan is up to 250 cm. It is also, in general, the largest predator of the northern hemisphere (with the exception of vultures, which are scavengers). Females differ from males only in size (females are larger and heavier). Contrasting "magpie" color is acquired only for 5-4 years of life, while young birds have a single-colored brown plumage. But all the outfits are characterized by a bright yellow beak - unlike other eagles, whose beak is gray-brown at a young age, and turns yellow only with age.
White-shouldered sea eagles live only on the sea coast of north-east Asia: along the coast of Kamchatka and the island of Lake Baikal. Sakhalin, along the coastline of the Sea of Okhotsk and in the lower reaches of the Amur River. During the wintering season, many birds migrate further south - to the southern Kuril Islands, Hokkaido Island, and Primorye.
For large dimensions, you have to pay - white-shouldered eagles are not capable of long-term active waving flight, they can afford such "work" for only 30 minutes a day. This is related to the choice of nesting sites - these birds settle near the sea, the source of their favorite food-fish. There is even a pattern in the distribution of fish-eating predators: the coast is "occupied" by the white-shouldered eagle, lighter white-tailed eagles nest further from the coast (their range covers almost the entire northern Eurasia) and even deeper on the mainland - the osprey, which is "used" to fly "fishing" tens of kilometers from the nest. The white-shouldered eagle chooses territories with high-trunked forests and rocky cliffs-suitable places to build a nest.
Unfortunately, it is the coast that is actively used by people for tourist purposes, transformed and transformed during the construction process. Water pollution and deforestation in these areas also negatively affect the population of these birds. In addition, overfishing severely affects the feeding base of eagles. And the most barbaric factor - poaching - also takes place. White-shouldered eagles are destroyed by fur trappers and fishermen; and in Japan, for a long time, they were destroyed by samurai for the sake of tail feathers - they used them for their outfit. The eternal paradox and absurdity of man: the admiration of any kind of animal leads to its destruction. In 2011, there were about 7,000 white - shouldered eagles in the world, and in 2015, there were already 5,000 (BirdLife International, 2015). Despite the ban on extraction and the inclusion of the species in all red lists, poaching and habitat destruction continues.
The vulnerability of this giant is compounded by the slow rate of reproduction. In addition, unfavorable conditions at the wintering ground or in the mountains in the breeding area can lead to the fact that many pairs simply do not start breeding. Eagles begin to breed at about 7 years of age (pairs form earlier - from 4). In the nest, which is a large building up to 3 meters in diameter, located on a tree or rock ledge, most often 2 eggs. Incubation begins after the first one is laid, so the chicks are of different ages (as in other birds of prey), so the phenomenon of the so-called cainism, in which one chick kills another. In addition, eagles ' nests are ravaged by sables, crows, and other predators.
A prominent representative of the feathered fraternity is the white-shouldered eagle.
The bird is powerful and quite large. In the prime of life, the mass of a predator can reach 9 kg. The wingspan is also impressive — up to 2.5 meters.
The white-shouldered eagle is a versatile hunter, so it is potentially dangerous for a wide variety of animals.
Most of its diet consists of sea fish. Mostly salmon and trout.
As already mentioned, the eagles ' favorite prey is fish, mainly representatives of salmon, cod, etc. They often gather in large groups during spawning and eat a large number of spawned, doomed to die fish. Eagles also attack birds or mammals-ducks, geese, gulls, baby seals, young arctic foxes, sables, hares, and so on; or even invertebrates-crabs, mussels - the range of potential prey of this predator is extremely wide. But still, depending on the part of the range, fish occupies from 50 to 80% in the menu of the white-shouldered eagle. Because of its weight and size, it is not as agile as an osprey, so it does not rush or dive into the water, but descends in a smooth line, grabbing the fish from the surface with powerful paws.
Like other eagles, the white-shouldered eagle allows itself to steal prey from other animals. So, it is able to select prey even from such large predators as the osprey, white-tailed eagle and golden eagle. Such robbery is called kleptoparasitism in science. For a vivid example, see and read the link: an American relative of the white-shouldered white-headed eagle took prey from a fox, raising it in the air
Huge curved claws and spikes on the inside of the fingers are ideal for holding slippery and twitchy prey. It is almost impossible to escape from these powerful pincers. No — it definitely won't work.
And in general-just a couple of beaks on the crown of the head are enough for the victim to stop resisting, resigning himself to his unenviable fate.
From time to time, white-shouldered eagles use a rather unusual way of catching fish.
Since the birds are very heavy, they can not dive under water. Accordingly, diving for prey is not an option. We have to catch those who wander near the surface of the water. Nothing out of the ordinary, except for one thing.
As a rule, the detection of prey occurs mainly during air patrols.When a fish appears on the surface, you need to react quickly, before it goes to the depth.
Therefore the eagle in such situations activates the system of emergency braking At the same time, he turns his head 180 degrees to control the situation. Despite the love of fish, the white-shouldered eagle will not refuse to diversify its menu with other prey — for example, mammals. Hares, arctic foxes and foxes are most often targeted. They can even handle seal pups. As such, white-shouldered eagles have no enemies. However, from time to time they "squabble" with golden eagles. However, while the birds are figuring things out, the crows quickly pull apart the prey, because of which, in fact, all the fuss began. Because in the "big feathered family" there is always the hungriest and very smart one.
Unfortunately, despite the measures taken to protect this beautiful bird, the species remains very vulnerable. Trends towards human development of an increasingly large part of the coast and the rate of deforestation do not allow predicting an increase in the number of white-shouldered eagles. Poaching is booming in both Russia and Japan. Water pollution from industrial effluents and human anxiety do not allow an increasing number of individuals to reproduce. A serious and effective program is needed to protect and restore the abundance of this species in nature before it is too late. Fortunately, it breeds in captivity - the white-shouldered eagle can be found in more than 100 zoos around the world.
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