Antipodean Albatross (Diomedea antipodensis)

Antipodean Albatross

[order] PROCELLARIIFORMES | [family] Diomedeidae | [latin] Diomedea antipodensis | [authority] Robertson and Warham, 1992 | [UK] Antipodean Albatross | [FR] Organiste olive | [DE] Not found | [ES] Not found | [NL] Antipodenalbatros

Subspecies

Monotypic species

Genus

Albatrosses are the ‘largest’ birds in terms of wingspan. Royal Abatrosses, for instance, may reach a wing span of almost 3.5m, which make them look like feathered sail plaines. They are also the largest members of the tubenose family. Only the smallest albatross species are equalled in size by the Giant Petrels (Macronectes). Albatrosses occur in all oceans, except the northern part of the Atlantic. In ancient times they were also present in that part of the world, but nowadays only an occasional straggler find its way to the North Atlantic. Most of the 24 species are Southern Hemisphere breeders, only three actually breed north of the Equator in the Pacific Ocean.
Albatross taxonomy is subject of discussion for a long time, and has been at times rather chaotic. Based on external characters: plumage patterns, tail shapes, bill structure (size, organization of the plates and coloration) albatrosses were, until recently, divided in 13-14 species in four ‘natural groups’: the Great Albatrosses, the Mollymawks, the North Pacific Albatrosses, grouped in the genus Diomedea and the Sooty Albatrosses Phoebastria. More recently DNA-analyses supports the division in four distinct groups but the were elevated to a generic status and has led to a splitting into 24 species: Great Albatrosses Diomedea (7 species), the Northern (Pacific) Albatrosses Phoebastria (4 species), the southern Mollymawks Thalassarche (11 species) and the Sooty Albatrosses Phoebetria (2 species). Recently this taxonomy is challenged by who proposed to lump some of the ‘species’ again based on their molecular analysis. Since then the discussion flared up and has not ended yet. Some list six species of Great Albatrosses, including two subspecies of Antipodian Albatross.

Physical charateristics

Huge albatross breeding in mixed white and brownish plumage. Juvenile very similar to juvenile Wandering Albatross D. exulans. Birds breeding on Auckland Island (subspecies D. a. gibsoni) are generally paler than those on Antipodes, Chatham and Campbell Islands (subspecies D. a. antipodensis). Breeding females have chocolate-brown upperparts with white vermiculations on back, white face mask and throat, white lower breast and belly with brown undertail-coverts, and white underwing with dark tip. Breeding females of D. a. antipodensis have broad brown breast-band. Breeding males are whiter than females but never as white as whitest Wandering Albatross. Pink bill. Males of D. a. antipodensis may be distinguished from D. a. gibsoni by darker cap and tail, and less white on the humeral flexure. Similar spp. Wandering Albatross is significantly larger, but possibly not separable with certainty in field. Bill lacks dark marks of Amsterdam Albatross D. amsterdamensis.

Listen to the sound of Antipodean Albatross

[audio:http://www.planetofbirds.com/MASTER/PROCELLARIIFORMES/Diomedeidae/sounds/Antipodean Albatross.mp3]

Copyright remark: Most sounds derived from xeno-canto

recorded by Daniel Lane


wingspan min.: 300 cm wingspan max.: 350 cm
size min.: 105 cm size max.: 115 cm
incubation min.: 90 days incubation max.: 100 days
fledging min.: 260 days fledging max.: 280 days
broods: 1   eggs min.: 1  
      eggs max.: 1  

Range

Pacific Ocean : Antipodes, Campbell and Auckland islands, NZ

Habitat

It nests from the coastline inland, on ridges, slopes and plateaus, usually in open or patchy vegetation, such as tussock grassland or shrubs.

Reproduction

Eggs are laid between late December and late January on the Auckland Islands, and between early January and early February on the Antipodes Islands. Hatching takes place between March and April, and chicks fledge after nine months departing in mid-December to early March. Breeding is biennial if chicks are successfully reared3. Fledglings do not return earlier than the age of three years old, and the youngest age of first breeding is seven years for Antipodes Island birds and eight years old for Auckland Islands birds19. Between 1991 and 2004, average productivity was 74% on Antipodes Island and significantly lower (63%) on the Auckland Islands.

Feeding habits

It feeds mostly on cephalopods and fish. Data from satellite tracking indicate that birds from the Auckland Islands forage mostly west of New Zealand over the Tasman Sea and south of Australia, while those from the Antipodes forage east of New Zealand in the South Pacific, as far as the coast of Chile, and have a larger overall range. Foraging was most concentrated over pelagic waters and deep shelf slope (up to 6000 m), with peaks of activity at 1000 m corresponding to seamounts and shelf breaks where productivity is high. Foraging trips are longer during incubation (7-13 days) than chick-rearing (average 4 days). Breeders and non-breeders have similar core foraging areas, though non-breeding juvenile males from the Antipodes Islands migrate east to the waters off Chile, and non-breeding juvenile males and females from the Auckland Islands forage westward to the south-eastern Indian Ocean.

Conservation

This species is classified as Vulnerable because it is largely confined to three small islands when breeding and is therefore highly susceptible to stochastic effects and human impacts. Recent data (2005-2008) from the Auckland Islands indicate declines in adult survival, productivity and recruitment, which, if confirmed by further monitoring, could result in a reclassification of Endangered or Critically Endangered.
Diomedea antipodensis is endemic to New Zealand, breeding on Antipodes Island (4565 breeding pairs annually between 2007 and 2009), the Auckland Islands group (Adams, Disappointment and Auckland), where four counts from 2006 to 2009 indicated a mean annual breeding population of 3277 pairs, Campbell Island (c.10 pairs), and Pitt Island in the Chatham Islands (one pair since 2004). The total average annual breeding population of 8050 pairs on all islands gives an estimated population of 44500 mature individuals in 2009.
Antipodean Albatross status Vulnerable

Migration

Non-breeding juvenile males from the Antipodes Islands migrate east to the waters off Chile, and non-breeding juvenile males and females from the Auckland Islands forage westward to the south-eastern Indian Ocean.

Distribution map

Antipodean Albatross distribution range map

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