Tristan albatross

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 1998. Albatrosses belong to the family Diomedeidae of the order Procellariiformes, along with shearwaters, petrels, storm petrels, and diving petrels. They share certain identifying features. First, they have nasal passages that attach to the upper bill called naricorns, although the nostrils on the albatross are on the sides of the bill. The bills of Procellariiformes are also unique in that they are split into between 7 and 9 horny plates. Albatrosses also produce a stomach oil made up of wax esters and triglycerides that is stored in the proventriculus. This is used against predators as well as an energy rich food source for chicks and for the adults during their long flights. 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 supported the split. Other studies have shown it to be the most genetically distinct member of the wandering albatross superspecies. This may be due to it diverging from their common ancestor before all its relatives, or because it underwent particularly strong genetic drift. Among the major experts, BirdLife International has split this species, Clements has not yet, and the SACC has a proposal on the table to split it. Diomedea refers to Diomedes, whose companions turned to birds. It is practically indistinguishable from the wandering albatross at sea; the Tristan albatross is smaller and has a slightly darker back. The Tristan albatross is and has a wingspan of up to . The Tristan albatross also never attains the full white plumage of the wandering albatross, and its bill is about shorter. The Tristan albatross feeds on fish and cephalopods. They breed biennially and will nest in wet heath from in elevation.