Taxonomy
Mollymawks are a type of Albatross that belong to Diomedeidae family and come from the Procellariiformes order, along with shearwaters, fulmars, 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. Finally, they 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. 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.
The White-capped Albatross is part of a greater complex of Albatrosses consisting of the Shy Albatross, Thasassarche cauta, Salvin's Albatross, Thalassarche salvini, Chatham Albatross, Thalassarche eremita. In 1998, Robertson and Nunn recommended a four way split, some experts agreed. BirdLife International agreed in 2007, ACAP agreed in 2006, and Brooke agreed in 2004. The SACC agreed to a three-way split, leaving steadi, the White-capped Albatross grouped with the Shy Albatross. James Clements has yet to agree on any of these splits. Finally, following Brooke, this species was shifted from Diomedea to Thalassarche, which was generally agreed upon by most experts.
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