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Wandering Albatross
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The Wandering Albatross, Snowy Albatross, or White-winged Albatross, Diomedea exulans, is a large seabird from the family Diomedeidae which has a circumpolar range in the Southern Ocean. It was the first species of albatross to be described, and was long considered the same species as the Tristan Albatross and the Antipodean Albatross. In fact, a few authors still consider them all subspecies of the same species. The SACC has a proposal on the table to split this species, and BirdLife International has already split it.
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Encyclopedia
The Wandering Albatross, Snowy Albatross, or White-winged Albatross, Diomedea exulans, is a large seabird from the family Diomedeidae which has a circumpolar range in the Southern Ocean. It was the first species of albatross to be described, and was long considered the same species as the Tristan Albatross and the Antipodean Albatross. In fact, a few authors still consider them all subspecies of the same species. The SACC has a proposal on the table to split this species, and BirdLife International has already split it. Together with the Amsterdam Albatross it forms the Wandering Albatross species complex. The Wandering Albatross is the largest member of the genus Diomedea (the great albatrosses), and is one of the best known and studied species of bird in the world.
Etymology
Diomedea exulans can be broken apart into Diomedea which refers to Diomedes whose companians turned to birds, and exulans or exsul which means an exile or wanderer referring to its lonely distant flights.
Description
The Wandering Albatross has the largest wingspan of any living bird, with the wingspan between .The longest-winged examples verified have been about , but probably erroneous reports of as much as are known. As a result of its wingspan, it is capable of remaining in the air without beating its wings for several hours at a time (travelling for every meter of drop). The length of the body is about with females being slightly smaller than males, and they weigh typically from . Immature birds have been recorded weighing as much as during their first flights. The plumage varies with age, with the juveniles starting chocolate brown. As they age they lose their color and get whiter. The adults have white bodies with black and white wings. Males have whiter wings than females with just the tips and trailing edges of the wings black. They also show a faint peach spot on the side of the head. The Wandering Albatross is the whitest of the Wandering Albatross species complex, the other species having a great deal more brown and black on the wings and body as breeding adults, very closely resembling immature Wandering Albatrosses. The large bill is pink, as are the feet. They also have a salt gland that is situated above the nasal passage and helps desalinate their bodies, due to the high amount of ocean water that they imbibe. It excretes a high saline solution from their nose.
Ecology
Behavior
They are a group bird and have a large range of displays from screams and whistles to grunts and bill clapping. When courting they will spread their wings, wave their heads, and rap their bills together, while braying. They live for about 23 years.
Feeding
They are night feeders and feed on squid, cephalopods, small fish, and crustaceans and on animal refuse that floats on the sea, eating to such excess at times that they are unable to fly and rest helplessly on the water. They are prone to following ships for refuse. They can also make shallow dives.
Reproduction
The Wandering Albatross breeds every other year. At breeding time they occupy loose colonies on isolated island groups in the Southern Ocean. They lay one egg that is white, with a few spots, and is about long. They lay this egg between 10 December and 05 January, in their nests, which is a large bowl built of grassy vegetation and soil peat, that is 1 metre wide at the base and half a metre wide at the apex. Incubation takes about 11 weeks and both parents are involved. They are a monogamous species, usually for life. Adolescents return to the colony within 6 years; however they won't start breeding until 11 to 15 years. About 30% of fledglings survive.
Range
The Wandering Albatross breeds on South Georgia Island, Crozet Islands, Kerguelen Islands, Prince Edward Islands, and Macquarie Island, and it ranges in all the southern oceans from 28° to 60°.
Relationship with humans
Sailors used to capture the birds for their long wing bones, which they manufactured into tobacco-pipe stems. The early explorers of the great Southern Sea cheered themselves with the companionship of the albatross in their dreary solitudes; and the evil fate of him who shot with his cross-bow the "bird of good omen" is familiar to readers of Coleridge's The Rime of the Ancient Mariner. The metaphor of "an albatross around his neck" also comes from the poem and indicates an unwanted burden causing anxiety or hindrance. In the days of sail it often accompanied a ship for days, not merely following it, but wheeling in wide circles around it without ever being observed to land on the water. It continued its flight, apparently untired, in tempestuous as well as moderate weather.
Conservation
The IUCN lists the Wandering Albatross as Vulnerable status. Adult mortality is 5% to 7% per year. It has an occurrence range of , although its breeding range is only .
In 2007, there were an estimated 25,500 adult birds, broken down to 1,553 pairs on South Georgia Island, 1,850 pairs on Prince Edward Island, 1,600 on Marion Island, 2,000 on Crozet Islands, 1,100 on the Kerguelen Islands, and 12 on Macquarie Island for a total of 8,114 breeding pairs.
The South Georgia population is shrinking at 1.8% per year. The levels of birds at Prince Edward and the Crozet Islands seem to be stabilizing although most recently there may be some shrinking of the population.
The biggest threat to their survival is long line fishing; however, pollution, mainly plastics and fishing hooks, are also taking a toll.
The CCAMLR has introduced measures to reduce bycatch of Albatrosses around South Georgia by 99%, and other regional fishing commissions are taking similar measures to reduce fatalities. The Prince Edward Islands are a nature preserve, and the Macquarie Islands are a World Heritage site. Finally, large parts of the Crozet Islands and the Kerguelen Islands are a nature preserve.
See also
- Sarus Crane - the tallest flying bird alive today
- Bustards, which contain the heaviest living flying birds
- Argentavis, the biggest flying bird ever to live
Footnotes
Further reading
External links
- ARKive -
- on the Internet Bird Collection
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