Blackcock, or black grouse, or field grouse (lat. Lyrurus tetrix) is a common bird of the pheasant family inhabiting forest, forest-steppe and partly steppe zone of Eurasia, including in Russia.
Throughout the range of sedentary or migratory; inhabits forest edges, along forest edge, in the valleys of large rivers.
A relatively large bird with a small head and short beak. The males are noticeably larger than females, their length of 49-58 cm, weight 1,0-1,4 kg, whereas the same indicators for females 40-45 cm long and 0.7-1.0 kg, respectively. The color is a pronounced sexual dimorphism.
The male is easily recognized by shiny black plumage with purple or green sheen on the head, neck, goiter and lower back, and bright red eyebrows. Belly in the back brown, with light tips of the feathers; the rump are contrastingly white. Primaries dark brown, with the so-called “mirrors” – white spots in the bottom half of the first to fifth feathers. More mirrors is expressed on secondaries, where they occupy a large part of the wing. Tail feathers of the tail black with a purple tint on the tips; the outer tail feathers are strongly bent to the side, causing the tail becomes lisoobrobna form.
The female is mottled, reddish-brown, with transverse gray, dark yellow and black-brown stripes. It looks similar to the female of grouse, but it is characterized by white “mirrors” on the wings and a small notch on the tail. Undertail are white. Young birds – both males and females have colorful plumage consisting of black-brown, yellow-brown and white stripes and spots.
Vocalization is different in males and females. Females emit a quick, cackling sounds “Ko-Ko-Ko” on the end often rastyagivanie. Males are loud and continuous chattering, or in case of approaching danger emit a muffled cry of “chuu-is”. Loud singing males are often heard during mating, which in Central Russia begins in half – the end of March, and in the North of the area in the half of April and continues until nastupleniya summer. During the peak summer season (July) and in the middle of winter the birds are usually silent.
Diving grouse in the snow
Usually a ground bird, but in the cold season rests in the trees, where it produces its food. The earth moves like homemade chicken runs quickly and takes off almost vertically. The trail is also similar to chicken but a bit smaller and shorter step. Kept steadily in the trees and move freely even on thin branches. The flight is fast and vigorous – grouse at a time can fly up to several tens of kilometers without stopping. Has good vision and hearing – in case of danger quickly takes off and flies away in the far distance. Usually active in the early morning and in the evening, before sunset. In extreme cold feeds once a day, for a while he crawled out from under the snow.
Social bird outside the breeding season, especially in winter, kept flocks. Pack size may vary within wide limits – there are known some cases up to 200-300 individuals in the same group. Groups are usually mixed, at least consisting of some males, very rarely some females. Winter flocks usually live in trees – usually birch-trees where they feed on buds. After nightfall they hide under the snow, forming a tunnel with a camera on the end. In cold days at temperatures below ?20 °C birds are able to spend up to 23 hours a day, getting out only to eat.This is how outstanding Russian ornithologist and writer Sergei Buturlin diving Kosachev in the snow:
The frost grows stronger in the evening, and before sunset the grouse are trying to find a warm and quiet place to sleep. Here is one Kosachev also starting to look at, cranes and ducks his head, some time goes through the legs of a bitch, and then immediately rushes down and disappears in the loose snow. His example is followed by other birds of the flock.
Possessing excellent hearing, when the creaking snow under the paws of a Fox, or under the ski, birds quickly broken through the snow and loud take off. The nature of litter remaining after overnight, the wells of the hunters determine whether the bird is alarmed or not – in the case of a calm evacuation shelter last litter are always liquid.
Common in forest, forest-steppe and steppe zones part of Europe and Asia from the Alps and British island in the West to the Ussuri region and on the Korean Peninsula in the East. The range borders are very vague, depending on population and cultural changes of the landscape is vulnerable to fluctuations in one direction or another.
It is known that in Western and Central Europe, black grouse inhabit mostly forests in mountainous areas – for example, in the Slovenian Alps, they are found only at an altitude of 1400-1800 m above sea level, although their range was much broader. In some regions of Central Europe, such as in the Eastern Sudetes, black grouse have almost disappeared due to human activities and climate change (more frequent formation of a thin layer of ice on the snow – crust). In addition to mountain forests in Western Europe the black grouse also inhabit Heath along the Northern coast of Belgium, the Netherlands, Denmark and Northern Germany. They occur also in great Britain up to Scotland and Scandinavia.
In Russia the Northern border runs through the Kola Peninsula (Kola Bay to the village Tetrino on the White sea), Arkhangelsk region (the lower reaches of the rivers Nes, the Mezen, the valley of the river Sula), the Republic of Komi (South of the mouth of the river of Ersu, the lower reaches of the Mustache, the valley of the river Great Kochmes, the lower reaches of the R. Sobey), Tyumen oblast (the rivers Poluy and Peliwo).
To the East of the Obi exact boundary not defined – it is known that Lena birds rise up to 64° N. lat., meet on the Northern border of lake Baikal, in the valley of the Argun and Gorin and further South to the river Ussuri and lake Khanka. On the Pacific coast birds are not found. The southern border runs through the North of Kursk, Voronezh and Volgograd regions, the southern edge of the Zhiguli hills, valleys of rivers Samara and the Urals, where it goes in Eastern Kazakhstan. Furthermore, the Russian border of the area is returned to the upper reaches of the Ob river, runs along the foothills of the Altai mountains and goes to China.
In Asia outside of the Russian Federation grouse inhabit isolated areas of Kazakhstan and Middle Asia, Mongolia, China and North Korea.
Settles where forest or scrubland are combined with open spaces – in small groves, coppices, woodlands with an abundance of berries in the valleys of major rivers, the edges of upper and transitional bogs, floodplain meadows or agricultural lands. Solid dark forest escapes, but is found on the extensive clearings or burned areas. Nearly the entire habitat prefers areas with a predominance of birch. Among the exceptions is the bogs and Moors of Western Europe and the bushes in the Ukraine and in the West of Kazakhstan. In the mountains most often lives on the upper or lower boundary of the forest.
The black grouse is sedentary or nomadic lifestyle. Seasonal movements are irregular, but in some years can cover a significant part of the population. Mobility can be associated with a lack of food in winter, so characteristic for this kind of significant fluctuations in the number – once every 4-10 years, the population of these birds may increase dramatically.
Like other members of the family, grouse are polygamous – one male has several females. With the early spring males gather together on so-called “tokovisch” – open areas surrounded by forest or brushwood, where the Kosach family “Lek” – a lively behave, rambling, copycat and chasing each other. As tokovischa may be the site of a bog, a meadow, a forest glade or even ice-covered lake in the first phase of winter. The number of birds on one current is typically 10-15 males, some of which are available during the season moved to neighboring areas. In early spring, when warm weather gives way to frost, calls can be interrupted due to bad weather and resumed warming.
The period of active mating occurs in the second half of April – first half of may and lasts approximately two weeks. On a Lek, each male has his own plot, carefully guarding it from other birds; the most powerful Kosachev occupy the Central part of the clearing. Some males spend the night on the site, others arrive there at night. Somewhere in the hour before dawn, the males begin to copyrite – loud hissing sounds, then move on to barrataria. Lek birds, as a rule, on the ground, but some species can climb to a tree branch.
A few minutes after the males to place females arrive first, holding on a little way, and then flying to the center tokovischa, choosing a partner for mating. In moments of excitation of the males circling on the spot, shifting from foot to foot, extend neck, open fan-shaped tail, jumping and chattering loudly. The whole process takes 1-1. 5 hours, but lasts unevenly – at times first increasing and then dying away. At some point, males can scatter, but in a few minutes returned to stomping ground again.
Between Kosachev, there are often conflicts, during which they chase each other or join the fight. Fighting Kosachev resemble cock – both opponents are closer, bends his head to the ground and leaping almost vertically, they’ll turn on each other. Despite the fierce nature of the fight, wounds cocks to each other is not applied. After sunrise calls quickly calms down and stops. The same process resumes and also in the evening, after sunset, but during these hours it is less intense.
After mating on the current role of males in reproduction process completely ends – they do not participate neither in the arrangement of the nest or in incubating eggs, no further raising of offspring. The female builds the nest near the tokovischa, usually not more than a kilometer. The nest is a small depression in the ground scantily lined from grasses, leaves, twigs and feathers. The diameter of the tray – 160-220 mm, depth is of 40-60 mm. most Often, the nest is located at the edge of the forest under cover of birch, juniper, nettle thickets, etc.
However, sometimes the socket is fully open on a glade or a meadow. Oviposition usually occurs in the middle of may and the first Chicks hatch in mid – late June. The clutch consists of 5-13 (usually 7-9) eggs are light buff with brown or brown marked. Incubation lasts 24-25 days.
Chicks vyvodnogo type – hatched, they are covered with thick down and after a few hours, leave the nest, following the female. The first 10 days – the most dangerous period for teerawat. At this time the female is inseparable near offspring, constantly listening for strange noises – in the event of an approaching predator, she tries to take him to the side, pretending to be “wounded” – running, spreading her wings, jumps and cackles loudly. Upon hearing the alarming cry of the mother, the Chicks scatter in different directions and sit quietly in the grass until the danger has passed. At the age of 10 days teerawat pereporhnut start and flying start in a month.
During the breeding season the males are kept separately – one by one or in small groups. At this time they are silent and are particularly fearful since, as a consequence of moulting temporarily lose the ability to fly.
The diet consists almost entirely of a variety of plant feed. In the spring, when females are required for reproduction of high-protein food, harvested inflorescences of cotton grass (Eriophorum), buds of birch, larch, alder; the various parts of heathy shrubs and grasses such as kaluzhnitsa marsh (Caltha palustris) or buttercups. In the summer and fall to eat the berries (blueberry, cowberry, blueberry, cranberry), different parts of herbaceous plants (clover leaves, aspen, lady’s mantle, bilberry; inflorescences of hieracium (Hieracium); fruit cherry, etc.). In areas of cultivation of grain crops forage in agricultural fields, in particular grains of wheat or millet.
In winter, the main food are sprouts, buds and catkins of birch, and where it is small, part of the other woody plants depending on the region they can be spruce needles spruce needles and juniper berries, shoots of the larch, the young cones of the pine, the buds of willow and alder, etc. Chicks, in contrast to adult birds, at first mainly feed on animal food – insects and other invertebrates animals, but with the growth of their share is gradually declining.