Snowy sheathbill

Chionis albus

Photo by Liam Quinn (Wikipedia)

Common name:
snowy sheathbill (en); pomba-antárctica (pt); chionis blanc (fr); paloma antártica (es); weißgesicht-scheidenschnabel (de)


Taxonomy:
Order Charadriiformes
Family Chionidae


Range:
This species breeds on the Antarctic Peninsula, and in sub-Antarctic islands along the Scotia Arc on the South Shetland islands, Elephant island, South Orkney islands, South Georgia and South Sandwich islands. Some birds migrate south to winter in the Falkland islands, Tierra del Fuego and Patagonia.

Size:

These birds are 34-41 cm long and have a wingspan of 75-80 cm. They weigh 460-780 g.

Habitat:

They are found on rocky or ice-covered islands, often amongst rotting piles of kelp on sandy and rocky beaches along shorelines, on tussock grass, meadows and lowland bogs. They also occur on icebergs. During the breeding season they are found amongst penguin colonies, and to a lesser extent, cormorant, albatross and seal colonies.

Diet:

Snowy sheathbills are omnivorous and opportunistic. During the summer they mostly eat regurgitated krill obtained by direct interference with penguins feeding chicks, but they will also eat penguin and cormorant eggs, excrement, and, to a lesser extent, young chicks. They also eat blubber and flesh off the skin and skeletons of carcasses, and forage on intertidal areas taking limpets and algae.

Breeding:

They breed in December-February. The nest cup is placed on the ground, generally within a penguin colony, and lined with a combination of bones, guano, moss, algae, dead chicks and even rubbish. The female lays 2-3 creamy-white eggs which are incubated by both sexes for 26-32 days. The chicks leave the nest after 30 days, but are only able to feed on their own after 1-2 months and may continue to follow their parents for food for up to 6 months.

Conservation:

IUCN status - LC (Least concern)

The snowy sheathbill has a relatively small breeding range and the global population is estimated at 20.000 individuals. The population is suspected to be stable, however, there is some evidence of a population decline in the vicinity of the Argentine islands.