A medium-sized, black-and-white marine shag with a metallic green-and-blue glimmer on the black head and neck. Note the white wing patches. Breeding birds have a prominent crest, red facial skin, a red-orange throat pouch, and magenta-pink eye-rings. Nests and roosts colonially on steep cliffs and rock ledges. Non-breeding plumage fades to brown, and crest is absent. Juveniles have brown facial skin and upperparts. Endemic to the Auckland Islands and only found in shallow waters nearby. Only shag species regularly inhabiting the Auckland Islands.