Black goose is extremely beautiful in flight and are able to overcome distances of thousands of kilometers. In addition, these birds – the smallest of the genus Branta.
Habitat, conservation status, abundance, open view
Black geese inhabit the Northern coast of Western Europe (the most Northern regions – the coasts of Germany, Denmark and the Netherlands). Members of the species also occur in South-Eastern regions of the British Isles, Atlantic coast of France, and inhabit the narrow strip of tundra in the Arctic part of the Chukotka and Yakutia.
There is also a population of black geese on the Pacific coast from Mexico to southern Alaska, and the Asian population on the Japanese Islands of Honshu and Hokkaido, Sandanska Peninsula, China and in Korea.
At the moment there are about 500,000 individuals of black geese. However, in 1970-e years the population number has declined significantly since restrictions on the hunting of a species at that time did not exist. Today, despite the ban, the threat of mind persists, because black geese like to graze on the grain fields, and therefore be subject to destruction. Surface water runoff from agricultural land into estuaries also brings significant damage to the number of black geese.
Atlantic black goose(Branta bernicla hrota) listed in the Red book of Russia
The presence of subspecies
Currently recognized three subspecies of the black goose. They all have the black coloration of the head, chest, tail and paws, differing only in the color of the sides and belly.
Branta bernicla hrota – has a light belly with pale brown and whitish feathers. The hunt for the representatives of this subspecies is prohibited. Breeds in Canada, Greenland, and nearby Islands.
Branta bernicla nigricans – in the belly of the representatives of this subspecies is painted black. Breeds in North America and Siberia.
Branta bernicla bernicla – has a darker belly and the overall light tone of the plumage. Breeds to the North of Europe and Asia.
Black geese inhabit coastal Arctic tundra and wet meadows with abundant low herbaceous vegetation. For a nesting members of the species choose sloping banks, covered with salt marshes, but nests may also be built on the grassy Islands in the ponds or river deltas.
The existence of species closely related to the favourable conditions of the coastal environment, and therefore on migration black Canada geese are often found on riverside banks covered with silt, as well as in areas of estuaries, shallow muddy bays. In addition, birds are attracted to fields planted with cereals.
Lifestyle, life cycle, life expectancy, enemies, reproduction in nature, courtship ritual, a way of behavior
View refers to the number of migratory species. Black geese migrate in dense, well maneuverable flocks can reach speeds up to 90 km/h due to the narrow, large wings.
In addition to seasonal, mind is inherent in the daily migration. In the morning on the ground foraging birds are kept for about two hours, then go to the sea to drink water and rest until mid-day. From noon until sunset again feed on the coasts, spending the night in the open sea.
For breeding birds are divided into pairs at the beginning of June, then creating a small colony.
Almost all the Chicks hatch at the same time and the parents were taken to the nearest pond. Chicks eating 13 to 14 hours a day until, until fledge (approximately the age of 40 days). The Chicks remain with the parents all winter. Puberty black geese reach the age of 2-3 years.
Life expectancy of black geese in nature is about 28 years old. In captivity this increases by approximately ten years, the maximum known lifespan of a black goose in captivity is 40 years.
The main enemy of the black geese – Fox. However, a threat to the mind imagine other predators. So, eggs and Chicks can steal gulls and Skuas.
The species has the most Northern region of breeding of all members of the genus.
For black geese is characterized as a colonial, and single-type territorial nesting, and in the second case the couple prefers to use a bird’s-patrons. So, there are cases when nests of black geese were located in close proximity to colonies of Arctic terns, glaucous gulls, herring gulls, nesting snowy owls, Skuas, peregrine falcons, zimnyakov.
The species prefers to nest near water, but may sometimes breed in the icy tundra (up to 10 km inland). For the construction of nests used vegetation and feathers, the female carries from 3 to 5, rarely 6-7 eggs.
The area around the nest actively protects not only the male but the female not only taking a threatening posture, but also in pursuit of the attackers.
The incubation period of eggs lasts 24 to 26 days, during this period the geese molt and can’t fly.
The courtship ritual of the black goose is quite complicated and long, while despite the fact that birds form pairs for life, each year, the male cares for the female through the poses. Mating commonly occurs in water.
Behavior
Black geese belong to social species, forming colonies at the period of nesting. However, may exhibit territoriality during the breeding season. The sociality of the species is reflected in the high degree of synchronization of the period of oviposition and hatching. Colonies of barnacles characterized by high density. Males after hatching are kept in separate flocks, females with broods may join the group. It simply monogamus, however, the courtship ritual is repeated annually. Finding regions with plentiful food, I try to travel minimally.
The choice of a partner from the black geese occurs on the basis of the similarity of the white collars. Before migrating to breed in the Northern regions they form a pair.
Food in the wild and feeding in captivity – General principles and options for seasonal feeding, the nature of the rations according to the experience of breeders.
Black goose is mainly herbivorous birds, however, they may also eat eggs, snails and worms, marine invertebrates, larvae of mosquitoes.
The birds feed mainly on land, but can also pick up from the water surface floating plants, or submerged in water, getting food at a depth of 50-70 cm
The power of black geese different in wintering and reproduction. In the first case, the basis of their diet are algae, the second – mosses, grass, algae and lichens.
The main groups of host plants that feed on black goose look like this:
- Grasses (Polygonaceae, Fabaceae, Asteraceae);
- Sitnikova and graminoids (Poaceae, Juncaceae);
- Sedge (Cyperaceae);
- Horsetails (Equisetaceae);
- Shrub willow (Salicaceae).
An important role in the nutrition of geese playing algae: Enteromorpha sp. especially in the winter. Birds can also drink salt water
Feeding in captivity
In captivity black goose needs to obtain a large number of plant foods, including fruits and vegetables. Youngsters should also get the sprouted grain.
It is desirable to include in the diet of adult eelgrass (Zostera marina) and other algae, if it is impossible – it is necessary every day to give them young or sprouted grains.
A favorite food of birds kept in captivity, is a salad. They also enjoy grazing on the territory of the enclosure. If this grass is not suitable, the birds must to give freshly cut grass.
As a Supplement you can give the black geese feed for chickens and the pellets for waterfowl.
Features of the captive breeding: number of eggs per clutch, incubation, incubation, the breeding expertise of breeders from abroad, sexual dimorphism.
The black goose in a cage is easy to get along with swans, various geese and ducks, often grazing with them. The only species with which the black goose can not get along – the Hawaiian goose.
In the cage should be a pasture with grass not above 7.5 cm.
It is important that the birds always had access to water, so the cage has to have a reservoir, preferably, to take up to 20% of the area of the enclosure. At the same time in the paddock during a severe frost black goose does not need, but small shed in the enclosure is needed. It can be mud or wood.
As a staple food for geese green feed in the enclosure, it is desirable to equip a nursery feeders.
During the breeding season of black geese, it is desirable to isolate in a separate enclosure, where you will have access to other birds (the male becomes aggressive).
Sexual dimorphism
Female and male specimens are superficially similar, but males usually larger than females and have wider light ring around the neck. Wing length of females 315-331 mm, males mm. 310-351 Weight 1415-1730 males, females around the year 1200 the Beak of 29-37 males, females 31-38 mm. Respectively, the weight of males in the period of shedding is shortened by 141 grams, females – 122 grams.
