Dark albatross
| Dark albatross | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dark albatross ( Phoebetria fusca ) |
||||||||||
| Systematics | ||||||||||
|
||||||||||
| Scientific name | ||||||||||
| Phoebetria fusca | ||||||||||
| ( Hilsenberg , 1822) |
The dark albatross ( Phoebetria fusca ) is a species of bird in the albatross family. It is a medium-sized, soot-black albatross with characteristically long, narrow wings and a narrow tail.
The IUCN classifies the sooty albatross as endangered ( endangered one). The population is estimated at 42,000 sexually mature individuals, but has been declining sharply for at least three generations (90 years). The longline fishery is one of the factors that endanger the stock . While the cats and rats introduced there obviously do not influence the population on the Kerguelen , the population on the Amsterdam Island has declined due to the predation by these species. There are around 58,000 copies in total.
Appearance
The dark albatross reaches a body length of 84 to 89 centimeters. The wing length is between 49 and 54 centimeters. The wingspan is 203 centimeters. The birds weigh between 1.8 and 3.03 kilograms. Females are usually slightly lighter than males and have smaller bills, slimmer legs, shorter tails, and slightly shorter wings. However, the dimensions of the two sexes clearly overlap.
Adult dark albatrosses have almost uniformly dark chocolate-colored to greyish plumage. In many individuals, the head is significantly darker than the neck, stomach and wings. The birds have a striking white eye ring that narrows towards the front eye ring. The feet and legs are light pink to bluish gray. The upper beak is light at the edge of the beak, so that the beak has a whitish stripe.
In young birds that are not yet sexually mature, the eye ring and the beak markings are darker.
voice
The dark albatross is mostly silent outside of the breeding season. In the breeding colonies he lets out a two-syllable call. The first syllable is shrill, the second syllable is a trumpet-like sound falling in pitch.
distribution
Dark albatrosses live in the south of the Atlantic and Indian Oceans. Most of the birds breed on Tristan da Cunha and Gough and the Prince Edward Islands . They also breed in small numbers on the Crozet Islands , Kerguelen and Amsterdam Island, as well as St. Paul .
Outside of the breeding season, the dark albatross can be found south of the 30th southern parallel. Odd guests occasionally reach New Zealand east of the normal range, in the southwest of the Indian Ocean they occur south to the 64th parallel south.
Reproduction
Dark albatrosses only breed every other year. The breeding season begins in October. They breed in small, loose colonies on overgrown and sheltered cliffs. The nest consists of soil and plant material, the nesting trough is covered with grass. The clutch consists of only one egg. This is white-skinned and has red-brown spots. The breeding season is 65 to 75 days. The young birds fledge after 145 to 178 days. Both parent birds are involved in nest building as well as in breeding and caring for the young birds.
supporting documents
literature
- Klaus Odening: Antarctic fauna, introduction to the biology of the Antarctic. Series of publications Berliner Tierpark-Buch. Volume 37, Urania, Leipzig 1984.
- Hadoram Shirihai: A Complete Guide to Antarctic Wildlife - The Birds and Marine Mammals of the Antarctic Continent and Southern Ocean. Alula Press, Degerby 2002, ISBN 951-98947-0-5 .
- James McQuilken: The Mists of Time. Spitzbergen.de-Verlag, 2012.
Web links
- Videos, photos and sound recordings about Phoebetria fusca in the Internet Bird Collection
- Phoebetria fusca in the endangered Red List species the IUCN 2008. Posted by: BirdLife International, 2008. Accessed on December 22 of 2008.
Single receipts
- ↑ BirdLife Factsheet on the Dark Albatross , accessed on November 28, 2010
- ↑ James McQuilken: The Mists of Time . Ed .: Rolf Stange. 1st edition. Spitzbergen.de, 2012, ISBN 978-3-937903-15-6 , pp. 137 .
- ↑ Shirihai, p. 130.
- ↑ Shirihai, p. 130.
- ^ Shirihai, p. 132.