The Tristan Albatross (Diomedea dabbenena) is a large seabird from the albatross family. One of the great albatrosses of the genus Diomedea, it was only widely recognised as a full species in 1998citation needed.
While not all scientists believe it is a full species with some retaining it as a subspecies of the Wandering Albatross, a 2004 study of the mitochondrial DNA of the Wandering Albatross species complex[1] supported the split. Other studiescitation needed have shown it to be the most genetically distinct member of the Wandering Albatross superspecies. This may be due to it dÃverging from their common ancestor before all its relatives, or because it underwent particularly strong genetic drift.
It is, however, practically indistinguishable from the Wandering Albatross at sea; the Tristan Albatross is smaller and has a slightly darker back. The Tristan Albatross is 110 cm (43 in) and has a wingspan of up to 3.5 m (11.5 ft).[2] section=factsAndStatusDue to the difficulty in distinguishing them from Wandering Albatrosses, their distribution at sea is still not fully known, but the use of satellite tracking has shown that they forage widely in the South Atlantic, with males foraging west of the breeding islands towards South America and females to the east towards Africa. At sea, they feed mostly on squid, most importantly cock-eyed squids (Histioteuthidae).
The Tristan Albatrosses are endemic to the islands of the Tristan da Cunha group and Gough Island. The majority of the world's population nest of Gough, around 1500 pairs. There are also colonies on Inaccessible Island. They were formerly threatened by introduced species, rats, cats and pigs, but these have now been removed from their breeding islands. However, this resulted in the population of mice increasing to the point where they would eat and kill albatross chicks en masse [3]. Even though the chicks are huge compared to the mice, they do not know how to defend themselves appropriately. Today the main threat to the species is believed to be long-line fishing.
Formerly classified as a endangered species by the IUCN[4], it was suspected to be more threatened than generally assumed and undergoing a marked decline. Following the evaluation of its status, this was found to be correct, and the Tristan Albatross is consequently uplisted to Critically Endangered status in 2008[5].
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