Gangly, stretched-out-looking black-and-white seabird. Strikingly slender and strange-looking in flight. Breeds in the rainforest canopy of Christmas Island, and forages in the adjacent ocean. Some birds, especially immatures, will forage much farther afield, but the extent of these rangings is still poorly understood. Bizarre long-necked and slender-winged profile is unique, and should readily distinguish this species from any others in range. Bill is pale pink in females and grayish in males.