The Antipodes Islands and the Auckland Islands each have a distinct form of wandering albatross, both unique to New Zealand. There are about 9,000 pairs of Antipodean wandering albatrosses (Diomedea antipodensis) that breed on the Antipodes, as well as a few pairs on Campbell Island and the Chatham Islands. Some 12,500 pairs of Auckland wandering albatrosses (Diomedea antipodensis gibsoni) breed on the Auckland Islands. Because great albatrosses breed every second year, only about half these numbers are on the islands in a given year. They eat squid, fish, octopus and crustaceans such as krill, and tend to feed over deep oceanic waters.
Both forms have dark-brown and white plumage, including a brown cap. They become whiter as they grow older, and Auckland wanderers have more white than Antipodeans at a given age. They have fine speckling on the breast that fades with age. Their bill is very large and pink.
When a royal or wandering albatross returns from foraging to take its turn on the nest, it calls out to its mate on approach. Once it has landed, the two usually sit together for some time, intermittently preening each other and cooing, until the one on the nest heaves itself off and allows the other to take its place. More preening and sitting together takes place before the bird that has been fasting for up to two weeks eventually goes to sea to feed.
Both royal albatross species breed only in New Zealand, but spend much of their non-breeding time off the coasts of South America. Like wandering albatrosses, they breed every two years.
Southern royal albatrosses (Diomedea epomophora) are the largest albatrosses. They have a breeding population of 14,000 pairs, almost all of which breed on Campbell Island, apart from 100 or more pairs on the Auckland Islands.
Most northern royal albatrosses (Diomedea sanfordi), about 6,500–7,000 pairs, breed on some of the remote islets of the Chatham Islands, but they are better known for the mainland colony of fewer than 30 pairs at Taiaroa Head, near Dunedin.
Their main foods are squid, fish, krill and salps. They feed over continental waters, especially along the break between the continental shelf and slope.
Both species have a large, yellow-pink bill with a black line along the upper cutting edge that differentiates them from wandering albatrosses. From above, their wings are black in early years, then with age the southern royal develops expanding areas of white, starting from the front edge, while the northern royal’s upper-wing surface remains mainly black. The black flecks on the white body disappear as they grow older, and males are whiter than females. Underneath, the body is completely white, and underwings are white with black margins and tips.