A medium-sized, black-and-white marine shag with a metallic green-and-blue glimmer on the black head, neck, and throat. Note the white wing patches. Breeding birds have a prominent crest and a yellow line above the gape of the long, pointed bill. There is a yellow patch at the base of the bill that fades to a bright red spot. Non-breeding adults lack the crest and plumage fades to brown. Juveniles are similar to adults, but with brown upperparts. Endemic to Campbell Islands and only found in shallow waters nearby. Only resident shag species on Campbell Island.