Also known as American Sheathbill, Yellow-billed Sheathbill, Greater Sheathbill, Pale-faced Sheathbill, Paddy
Latin name: Chionis alba
Population: The Snowy Sheathbill’s population consists of approximately 10,000 pairs.
Conservation status: Least Concern (IUCN, 2008)
Where found: During the breeding season Snowy Sheathbills can be found round the rocky shorelines of the Antarctic Peninsula, South Shetlands, South Orkneys and South Georgia. Non breeding birds and during the winter (of the Southern Hemisphere) birds are found in the south east of South America – Patagonia, Uruguay, the Falklands and occasionally as far north as Brazil.
Wingspan: 74-84 cm
Length: 34-41 cm
Weight: 460-780 g
Mating/Breeding: The Snowy Sheathbills breed as far south as 65°, returning to the territory in October/November. The Snowy Sheathbills nest in dark caves or crevices, where there is an overhang – scree burrows, empty huts, spaces between abandoned fuel drums and the detritus of scientific stations. The nest is a bulky, compacted mass of moulted penguin and gull feathers, dead chicks, bones, pebbles, limpet shells, moss, lichens and weed. Mainly solitary at nesting time, Snowy Sheathbills tend to be in close association with gentoos or chinstrap penguins or shag colonies, close to the sea, often on a ridge overlooking the colonies which provide their food. 2 to 4 eggs, laid in December/January, are incubated by both parents for 28 to 32 days and fledged in 7 to 9 weeks, in late February. Most pairs only succeed in raising one or two chicks.
Hunting Habits: Master scavengers. The Snowy Sheathbills even steal food right from the mouths of feeding penguin chicks (called kleptoparasitism).
Feed on: Omnivorous – steals krill, fish, eggs and small chicks from breeding penguins – also eat carrion, faeces, algae and invertebrates – limpets are common.
Threats: Not globally threatened and population considered stable, though poisoning from human-chemical waste products may have occurred in some areas in the past .
Colour/Looks: With their thick, entirely white plumage and sturdy bodies, Snowy Sheathbills are well adapted to the cold Antarctic environment. The Snowy Sheathbills have short, stout blue-grey or pink legs, the toes having only vestigial webs. The blunt bill is covered with a horny yellow-green sheath with sharp carpal spurs used in territorial fighting.
- The Snowy Sheathbills are Antarctica’s only permanently land-based bird.
- The Snowy Sheathbills are the only species in Antarctica not to have webbed feet.
- The Snowy Sheathbills regularly roost on one leg.
- Hadoram Shirihai, A complete guide to Antarctic wildlife (2002)
- David McGonigal & Lynn Woodworth, Antarctica and the Arctic. The complete encyclopedia (2001)
- Tony Soper, Antarctica. A guide to the wildlife (2000)