Tuatara: Volume 21, Issues 1 and 2 (New Zealand Albatrosses and Petrels: an Identification Guide)
3. White-Capped Mollymawk — (Diomedea cauta cauta) — Plate 3
3. White-Capped Mollymawk
(Diomedea cauta cauta)
Field Characters: 255/96. Distinguished from the other subspecies of this group (4 and 5) by its white head (including cap) which contrasts sharply with the dark mantle. The cheeks are flushed with light grey. Upperwings and mantle black from wing tip to wing tip; rump white, tail dark grey. Underbody white. Underwing white, narrowly bordered with black; wing tips black. A black spot contiguous with the body and the anterior margin of the underwing is characteristic of all three D. cauta subspecies. Juveniles have grey head and neck, and white throat. Underwing as for adult birds.
Bill pale greenish-grey with tip of both mandibles yellow in adult birds. With juveniles the bill is dark grey with a black tip, only becoming lighter with age. The tip of the lower mandible is the last area to lose its dark colour. The feet are light bluish-grey.
Differs from Salvin's (4) and Chatham Island (5) Mollymawks by its white head and neck, contrasting with the black back. Juvenile birds cannot be differentiated from juvenile Salvin's Mollymawks (4) at sea.
Flight similar to that of the great albatrosses.
Seldom follows ships, but will gather about fishing vessels for offal, for which it quarrels noisily.
Breeds at the Auckland Islands, on Albatross Island in Bass Strait and on Mewstone Rock, southern Tasmania. Common in New Zealand waters.