Bird Families

White-headed Duck / Oxyura leucocephala

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A peculiar group of freshwater ducks with a relatively long tail of hard feathers, which birds often hold almost vertically. At the base of the beak, many have a slight swelling. Most have a well-pronounced sexual dimorphism in color. They inhabit all continents except Antarctica. They live in fresh water bodies, strongly overgrown with near-water vegetation, as well as in well-watered bogs. This tribe includes the black-headed duck (Heteronetta atricapilla), which lives in South America, the white-backed duck (Thalassomis leuconotus) - in South and East Africa, as well as representatives of the Okuiga genus.

Species: Oxyura leucocephala (Scopoli, 1769) = White-headed Duck

STATUS. Little-studied species (IV category)

Habitat: Rare, sporadically widespread, poorly studied species with decreasing numbers. Wing length 147-165 mm. Lakes of the steppe zone.

Spread. Breeds on the steppe lakes of the Caspian and Lower Volga regions (Sarpinskoe Lake) northward to Volgograd, along the middle reaches of the Urals, in the Chelyabinsk region, in the Tobolo-Ishimskaya, Barabinskaya and Kulundinskaya steppes, in the foothills of Altai, in the Tuva and Ubsunurskaya depressions (1 - 3). In addition, in Kazakhstan, Turkmenistan, Tajikistan. The main wintering grounds are Krasnovodsk Bay, the vicinity of Hasan-Kuli, in the north of India, Pakistan, Western Asia, and the northern coast of Africa. Inhabits steppe lakes with dense reed beds and rafters (2,3). Nests are located mainly at the water's edge along the edges of rafters and thickets of reed and cattail. The habitat area varies significantly from year to year due to the water level fluctuations characteristic of these places. Migrates through Turgai and Aral to the Caspian, Iran and Pakistan, and also through the northern Caspian and the Manych valley to Turkey and North Africa.

The number. The total number is unknown, although it is clear that it is constantly decreasing and is generally small. So, on the lake. Mole Lyaga (Northern Kulunda) in 1966, 15 pairs of white-headed duck were recorded, in 1967 - 12, in 1969 - 4, and in 1970 - only 3 pairs (3). On the lake. Nyashino (Armizonsky District, Tyumen Region) in June 1977, 14 pairs of white-headed duck were recorded in the colony of terns. In Baraba on the lake. Cape June 10, 1973 1 nest was found. On the lake. Belukha On May 7, 1975, 3 pairs of white-headed duck were recorded, on the lake. In 1973, up to 15 birds were observed pretty, and in 1975 15 white-headed duck were counted (8, 9). In the winter of 1973 - 1974. 918 birds were counted in Pakistan (5), in Turkey in 1974 - 5740 (6). In total, there are about 15 thousand individuals in the world (7).

Limiting factors. Apparently, the white-headed duck is a relict endangered species. At present, the situation is aggravated by the negative influence of periodic fluctuations in the water level, deterioration of nesting sites due to anthropogenic activities, fishing, thinning of reed thickets by muskrat.

Security measures. Protected in a number of forest-steppe reserves for waterfowl. Duck hunting is prohibited. Special security measures have not been developed.

After identifying the nesting sites of these birds, it is necessary to organize the protection of a number of overgrown steppe and forest-steppe lakes, especially the areas occupied by colonies of gulls and terns, to prohibit fishing at the edges of thickets and rafters, on local reaches during the nesting and chick periods, and hunting at wintering sites should be prohibited. ... It is required to organize a nature reserve on the Chany and Chernoe lakes. It is recommended that you explore the possibilities of captive breeding of duck duck.

Sources of information: 1. Isakov, Ptushenko, 1952, 2. Dolgushin, 1960, 3. Ivanov, 1974, 4. Isakov, 1963, 5. Koning, Dijksen, 1974a, 6. Koning, Dijksen, 1974b, 7. Matthews, Evans , 1974, 8. Drobovtsev, Koshelev, 1980, 9. Azarov, Ivanov, 1981. Compiled by GK Ivanov.

SAVKA (Oxyura leucocephala) duck of medium size, its weight ranges from 0.4 to 0.9 kg. This is a kind of duck, which differs from other species in a number of features. The white-headed duck is immediately recognizable by its swimming style with an almost vertical tail. At the same time, she sits quite high on the water, but in case of danger she immerses her body in water so that only the very top of her back remains on the surface, she also floats with strong waves of water. White-headed duck swims beautifully and dives remarkably, yielding in this, perhaps, only to cormorants and loons. It can swim under water, changing direction, up to 30-40 m. It dives without a splash, as if drowning, and, having emerged from the water, is able to dive again in a second and swim the same distance under water. It flies reluctantly and rarely, never goes to land. Her whole life is spent on the water. The female is monotonously brown, while the male has a white head at a distant distance.

This duck nests on steppe lakes with reed thickets and open reaches with rich aquatic vegetation. It makes nests floating, among the reeds, at a shallow depth. In the clutch, there are most often 6 eggs, striking in their size: they are much larger than mallard eggs and are approximately equal to the eggs of a sheath. The nest, on the other hand, is relatively small. The eggs are off-white.

One female incubates eggs. The incubating female can never be found in the nest, which is apparently connected with the peculiarity of the development of eggs. It is believed that very large eggs of this duck need constant warming only for the first time and the embryos developing in them very soon acquire the ability to independently thermoregulate, ensuring their further development. There is a known case when the incubated white-headed duck eggs taken from the nest, which were in the rooms without any heating, developed normally and chicks hatched from them a week later. Downy chicks have hard tail feathers. Chicks raise their tail as adult birds do. The duck feeds on the leaves and seeds of various aquatic plants, as well as aquatic insects, molluscs and crustaceans. The commercial value of the white-headed duck is small, since its abundance is never high anywhere.

Description

The male in the breeding feather is mostly brown-rusty, with small black-brown dashes and specks. The head is white, with a black crown and a black collar. Flight feathers are brown, axillary white, tail is black, upper tail coverts are dark red, undertail is buffy with black streaks. Chest and flanks with brownish-red and black blurred transverse stripes. The belly is grayish-brown. The female differs from the male in the color of the head: the female's head is generally dark brown, with rather wide white stripes above the eye and near the neck, the collar is grayish with brown spots, the upper tail coverts are cross-striped. The male's beak is bright blue, the female's is grayish-blue, the legs are gray, with a slightly greenish tint. The eyes are nutty. Weight - 510-890 grams, wing - 145-170 mm

Spread

Before, the white-headed duck nested on fresh and brackish water bodies of plain Kazakhstan very widely, but in recent years it was occasionally found in the central and western regions of the republic, in the Naurzum reserve, as well as in northern Kazakhstan. Not found in the lower reaches of the Syr Darya. One male sighted on 14 July 2001 at Shoptykol Lake near Zharma. On June 11, 2004, a brood was recorded at Lake Alakol. The number of white-headed duck has been decreasing in recent decades. On migration it can be found everywhere. On the Kyzylkol lake, near Karatau, on September 14-17, 2001, 2833 White-headed Duck were observed, almost 1800 birds were found in mid-September, and 800 birds in mid-October 2002, and 2000 White-headed Duck in September 2003.

Biology

White-headed duck is a rare breeding migrant. Inhabits fresh or slightly salty deep reed lakes and open water bodies on plains. Appears very late, rarely in mid-March, mainly in April - end of May. They arrive in small flocks of up to two dozen birds, flying, probably, mainly at night. They breed in separate pairs. The nest is built from fresh reed leaves and lined with fluff, resting on the water in reed thickets or on floating reed islands. Clutches of 5-7 large eggs in late May - mid-July. Young birds were recorded from mid-June to late August. I.A. Dolgushin (1960) assumed that the white-headed duck does not incubate eggs all the time, as they develop independently. Subtle autumn migration occurs from mid-September to late October, some birds stay until mid-November.

Sources of information

Gavrilov E. I., Gavrilov A. E. "The Birds of Kazakhstan". Almaty, 2005. "Birds of Kazakhstan" volume 1. "Science". Alma-Ata, 1960.E.I. Gavrilov. "Fauna and distribution of birds in Kazakhstan". Almaty, 1999.

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