Sheathbills | Chionidae

IJshoenders | Picovainas

Two species make up the only bird family confined entirely to Antarctica and the sub-Antarctic islands. Black-faced Sheathbill breeds on the Prince Edward Islands, among others. Snowy Sheathbill winters in Patagonia and occasionally turns up on southern African shores, often ship-assisted. Both are stocky, pigeon-sized birds in all-white plumage. The family is named for a horny sheath that saddles the base of the upper mandible. Bare, warty skin around the eye and a bony carpal spur on the wing complete the odd look. They are the only Southern Ocean birds without webbed feet. They live almost wholly on land, walking with a hen-like gait and flying only when they must. As opportunistic scavengers they take carrion, seal placentas, faeces, kelp, invertebrates from the tideline, and penguin eggs and chicks. They also rush penguins at the moment of feeding, jostling them into dropping regurgitated krill. Pairs hold territories within penguin colonies and nest in rock crevices, timing breeding to the penguins' food supply. Of two or three chicks, usually only one fledges. The family is an ancient, isolated shorebird lineage whose closest living relative is probably the Magellanic Plover.