Nisaetus Cirrhatus – Wikipedia

L’ eagle with a variable tuft ( Nisaetus cirrhatus ( J. F. Gmelin, 1788 )) is a bird of the bird of the Accipitridi family widespread in a vast area of ​​Southeast Asia ^[2] .

Size [ change | Modifica Wikitesto ]

Measures 51-82 cm in length, for a weight of 1300-1900 g; The wing opening is 100-160 cm ^[3] .

I wait [ change | Modifica Wikitesto ]

The nominal breed of the eagle with a variable tuft has a black -striated reddish head of black and surmounted by a long black ridge made up of four feathers. The rest of the upper parts is brown, while the wing covers are generally clearer. The tail is light brown with a large subterinal band and three or four narrow dark brown bars. The brown feathers of the wings have large black ending and have four or five dark bars. The lower parts are whitish. The throat and chin are black striated, while the chest and sides are striated of dark brown. The back of the sides is suede color. The thighs and under-coud-chair covers are finely striated in white. The eyes and legs are yellow, the wax is yellow-greenish.

The eagle with a variable tuft presents a slender and longilinear shape, impression reinforced by the long tail. Its lower parts clearly clear strips of brown make it almost unmistakable. The sexes are identical, but the female is larger. Young people have a lightly blended white head of suede. Their wings are bordered for most of the light color. Their lower whitish parts are variously stained with brown on the chest. The different subspecies vary together for the color of their plumage and for their size. The breeds of the andaman (56 cm) and Simeulue (62 cm) are substantially smaller, while subspecies limna (60-72 cm) is by far the largest. Two subspecies ( cirrhatus It is ceylanensis ) have a well -developed ridge, while in the other three ( limna , andamanensis It is vanheurni ) It is absent or very reduced. In some subspecies we can find two different forms, a clear phase and a dark phase. In general, the island subspecies never have the dark phase, with a brown-coccolato plumage ^[3] .

Voice [ change | Modifica Wikitesto ]

The cry of the eagle with a variable tuft is a kleee-kle-ek Resonant and noisy that the bird emits both when it is posed and when it is in flight. It can also issue a ki-ki-ki-ki-ki-ki-keeei Fast, rather discreet and short at the beginning, but which grows gradually to end in a scream ^[3] .

The eagle with a variable tuft generally lives alone or in pairs. It is a rather shy bird, although it is possible to approach it a short distance when it resides inside or near a village. As soon as he is disturbed, he hurries to fly inside the vegetable cover to find it shelter. This rapace hunts waiting from a poseing that uses regularly, day after day. His hunting technique is very simple: he is patiently waiting for himself right on a branch and as soon as a prey ventures out of his refuge he lets herself fall to the ground and capturing her with her claws. Most of the prey are captured on the ground, but some birds are grasped between the trees. L’Aquila with a variable tuft Plana often above its territory, but it is likely that it spends even more time on its poseing on the edge of a clearing. Even if it is rather sedentary and you love to use the same place frequently, when the eagle hunts from the variable tuft it sometimes changes observatory to locate its victims. In this case, it moves from one poseing to the other with vigorous beats of the wings ^[3] .

Hair [ change | Modifica Wikitesto ]

When Plana above its territory, its wings are parallel and kept horizontal during the flight, a feature that allows you to distinguish this species from the eagle from the tuft of Hodgson ( Nisaetus nipalensis ), which has an appearance very similar to his ^[3] .

Diet [ change | Modifica Wikitesto ]

The eagle with a variable tuft feeds on a great variety of prey, such as mammals, birds and reptiles. Mail hunt between the foliage and wait patiently that a rooster, a pheasant, a hare or any other small mammal venture out of his refuge ^[3] .

Reproduction [ change | Modifica Wikitesto ]

In the eagles from the tuft Variable the wedding parade is just sketched and is often limited to a few planati flights accompanied by screams above the nesting area. Reproduction does not necessarily take place every year. In the northern part of the area, it takes place during the dry and cold season (from December to April). In the areas of tropical forest, the season is more variable. Couples usually have only one nest that can be reused for several following years. The latter is a voluminous structure made with pieces of wood. The interior is lined with green leaves. It measures about 1.05 meters in diameter and 1.20 m deep. The nest of the eagle with a variable tuft is built about 12 meters from the ground on a large tree, often located near a watercourse. Both adults participate in the choice of the site and the construction of the structure. The brood includes a single egg, opaque white, with some light red spots scattered on the wider part of the shell. Some eggs are often without signs. The incubation is carried out by the female only ^[3] .

Depending on the region, this species attends habitat not completely similar to each other. The nominal subspecies attends the open wooded areas, the tree -lined savanes, the grown land and the margins of the villages up to 1500 m. The specimens of the subspecies limna who live in the northern part of the Indian subcontinent appreciate in particular the forest counterfeits of the mountains and the wet forests up to 2200 m. The subspecies that live in the islands, in particular the Malaysian and Indonesian populations, are forest birds par excellence. They are mainly found in the dense rain forests, although sometimes they also attend open areas and even the rice fields.

The eagle with a variable tuft is endemic of the Asian continent. He reproduces in India, Sri Lanka and Southeast Asia, up to Indonesia and the Philippines ^[3] .

Five subspecies are recognized, two continental and three insular ones ^[2] :

• N. c. cirrhatus ( J. F. Gmelin, 1788 ), present in India south of Rajasthan and the gangetic plain;
• N. c. ceylanensis ( J. F. Gmelin, 1788 ), endemic of Sri Lanka;
• N. c. andamanensis ( Tytler, 1865 ), endemic of the Andaman Islands;
• N. c. limnaeetus ( Horsfield, 1821 ), widespread in northern India, in Nepal, Bangladesh, Burma, Indochina, the Malaysian Peninsula, in the large islands of the probe and in the western and south-eastern islands of the Philippines (Palawan, Mindoro, Mindanao);
• N. C. vanheux ( Boy, 1936 ), endemic by Simeulue (an island west of Sumatra).

Although it is a protected species, the eagle with a variable tuft sometimes falls victim to illegal hunting and poaching. In addition, it also suffers from the destruction or degradation of his habitat . Nonetheless, the species does not seem, at least for the moment, threatened, so much so that it is still classified as “at a minimum risk” ( Least Concern ) from the iUcn ^[first] .