Loons
| Loons | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Common loon ( Gavia always ) |
||||||||||
| Systematics | ||||||||||
|
||||||||||
| Scientific name | ||||||||||
| Gavia always | ||||||||||
| ( Brünnich , 1764) |
The common loon ( Gavia always ) is a species of bird from the genus of the loons ( Gavia ). The species breeds in the tundra and boreal coniferous forest in northern North America, Greenland and Iceland, and winters on the coasts of North America and Europe.
In Central Europe, the common loon can be seen regularly in the coastal regions from November to March in small numbers as migrants and winter visitors. It can also be seen much less frequently inland. Since the 1970s, he has been observed again and again at Lake Geneva and Lake Constance .
description
_in_the_Morro_Bay.jpg)
The common loon is the second largest species of the genus Gavia after the yellow-billed diver . It reaches a body length of 73–88 cm and a wingspan of 122–148 cm. The animals weigh 3.6-4.5 kg and are about as heavy as a gray goose .
The species is unmistakable in the magnificent dress . The basic color of the entire top and of the head and neck is black. The upper back shows dense rows of large white squares, the rear back and the flanks show fine rows of white dots. The neck has a transversely oval field of irregular white longitudinal lines on the sides and a narrow line of white dots on the throat. The chest, abdomen and the under wing coverts are pure white. In contrast to the black-throated and red-throated divers , the great loon does not wear the full adult splendor before at the earliest in its fourth calendar year.
The large beak is dark gray to black and straight, it is kept almost horizontal when swimming by an appropriate head position. The legs and feet are gray. The iris is wine red.
In the plain dress , the entire top is dark gray. The head and back of the neck are also dark gray, the dark color changes quite abruptly to white at the front of the throat and neck. On the lower neck, a blackish half-ring is clearly set off from the rest of the gray. There is a small white area around the eye. The beak is bluish gray-white, dark gray at the tip and on the ridge. The forehead is raised steeply. In the plain dress, the common lover can be confused with the yellow-billed diver. The yellow-billed diver, however, has a paler and slightly raised beak. The range of the two species, however, only overlaps slightly.
The youth dress is very similar to the plain dress, but the birds are overall lighter gray on the top, the contour feathers on the top and the flanks are also lightly edged and thus show a clean wave pattern. The beak is usually only dark on the ridge.
Vocalizations
The flight calls resemble those of geese , like those of other loons . The courtship calls are quite variable, most often a far-reaching, plaintive "aaoooh ... WÜH wü-a WÜH wü-a WÜH wü-a" can be heard.
Outside the breeding season, the common lover is usually not very vocal.
distribution and habitat
The distribution area of the ice divers includes the tundra and taiga in northern North America from about 40 ° N to the Arctic , the species is also found in Greenland , Iceland , Bear Island and Jan Mayen . During the breeding season, the species inhabits large and deep inland lakes.
Individual young birds were driven south by strong storms, which resulted in sightings at Lake Constance and the Mediterranean .
nutrition
The food is hunted by diving and consists mainly of smaller fish, frogs , crustaceans and molluscs are also captured. When hunting fish, it usually dives three to ten meters deep, sometimes up to 200 m.
Reproduction
The partners arrive in the breeding area paired. In addition to the calls, courtship includes ceremonial beak immersion and many other elements. The nests are built directly on the banks of the water and consist of parts of plants from the area. The eggs are laid from the end of April, usually in May and June. The clutch usually consists of two, only very rarely one or three eggs, which are darkly spotted on an olive-brown to dark-brown background. The breeding season lasts 25–29 days. The eggs are incubated by both parents and the chicks are then led together. The young birds are independent after ten to eleven weeks.
hikes
Ice divers are predominantly medium to short-range migrants . Withdrawal from the breeding area starts in late summer and ends in October. The breeding birds of Greenland and Iceland overwinter on the sea around Iceland, Great Britain and on the European Atlantic coast from northern Norway to southern Portugal. The populations of North America overwinter off the entire North American Pacific and Atlantic coast. The return to the breeding areas takes place in May and June. The species is regularly found in very small numbers in Central Europe, predominantly from November to March, especially on the coasts of the North and Baltic Seas; only exceptionally inland on larger lakes.
Existence and endangerment
Information on inventory trends is not available. The world population was estimated by the IUCN in 2002 at 580,000 individuals and is considered safe.
Trivia
The common loon is the national bird of Canada. The Canadian province of Ontario and the US state of Minnesota have also chosen it as their symbol. It is depicted on the Canadian one dollar coin. This coin is called "Loonie" after the English name of the Common Loon .
Web links
- Gavia always in the endangered Red List species the IUCN 2008. Posted by: BirdLife International, 2008. Accessed January 2 of 2009.
- Videos, photos and sound recordings of Gavia always in the Internet Bird Collection
- Feathers of the common loon
literature
- Hans-Günther Bauer, Einhard Bezzel , Wolfgang Fiedler (eds.): The compendium of birds in Central Europe: Everything about biology, endangerment and protection. Volume 1: Nonpasseriformes - non-sparrow birds. Aula-Verlag Wiebelsheim, Wiesbaden 2005, ISBN 3-89104-647-2 .
- Einhard Bezzel: Compendium of the birds of Central Europe. Nonpasseriformes - non-singing birds . Aula, Wiesbaden 1985, ISBN 3-89104-424-0 , pp. 16-17.
- National Geographic Society: Field guide to the birds in North America . Washington 1983, pp. 18-19.
- Richard Sale: A Complete Guide to Arctic Wildlife. Christopher Helm Publisher, London 2006, ISBN 0-7136-7039-8 .
- Lars Svensson , Peter J. Grant, Killian Mullarney, Dan Zetterström: The new cosmos bird guide. Kosmos, Stuttgart 1999, ISBN 3-440-07720-9 , pp. 14-15.
Individual evidence
- ↑ Hans-Günther Bauer, Einhard Bezzel , Wolfgang Fiedler (eds.): The compendium of birds in Central Europe: Everything about biology, endangerment and protection. Volume 1: Nonpasseriformes - non-sparrow birds. Aula-Verlag Wiebelsheim, Wiesbaden 2005, ISBN 3-89104-647-2 , p. 199.
- ^ Richard Sale: A Complete Guide to Arctic Wildlife. 2006, p. 59.
- ^ Richard Sale: A Complete Guide to Arctic Wildlife. 2006, p. 59.
- ↑ a b Gunter Steinbach (Ed.): Wasservögel (The colored nature guides). Mosaik Verlag, Munich 1986, p. 118.