Scientific name: Pagodroma nivea
Physical description
Snow petrels are an all-white, small fulmarine petrel with conspicuous dark eyes, small black bill and bluish-grey feet. There are two subspecies of snow petrel that differ only in size.
Distribution and abundance
Snow petrel breed on South Georgia, the South Sandwich Islands, South Orkney Islands, Bouvet, the Balleny Islands, and Scott Island and at numerous localities on the Antarctic Peninsula and Antarctic Continent.
Snow petrel are almost entirely restricted to cold antarctic waters and are associated with pack ice, icebergs and ice floes. Flocks are characteristically seen sitting on icebergs.
Snow petrel nest colonially in small to large colonies on cliffs, usually near the sea, but also inland. Some birds remain at the colony all year, but the main influx of birds to the colonies is from mid-September until early-November.
Conservation status: least concern
Breeding
The nest is a simple pebble-lined scrape usually in a deep rock crevice with overhanging protection. One white egg is laid in late November to mid-December. The egg is incubated for 41–49 days and the chick is brooded for eight days. The chick then remains in the nest for an additional seven weeks. Snow petrel chicks leave the nest in late-February to mid-May.
Diet and feeding
At sea, snow petrel eat mainly fish, some cephalopods (squid), other molluscs, and euphausiids. They also feed on seal placenta and the carcasses of dead seals, whales and penguins, and occasionally eat refuse on land. Snow petrels do not normally follow vessels.
Snow petrels tend to fly low over the water but very high over land to avoid predators such as South Polar skuas.
Skuas are major predators, but severe weather conditions, especially heavy snow that blocks nest entrances, may cause adults to abandon their eggs or chicks to starve. Egg mortality is approximately 50% while chick mortality is typically 10–15%.