Scientific name: Pachyptila desolata
Physical description
Antarctic prion are the largest of the prion, with a wing span of 17–20cm.
Distribution and abundance
Breeding colonies are found on South Georgia, the South Sandwich Islands, the South Orkney Islands, the South Shetland Island, Iles Crozet, Iles Kerguelen, Heard Island, Macquarie Island, Auckland Island, and Scott Island.
Antarctic prion are highly gregarious with flocks comprising thousands of individuals commonly seen at sea.
Conservation status: least concern
Breeding
Antarctic prion arrive at their colonies in October to early November. They nest on exposed rock faces of cliffs, in cavities under boulders or in short twisting burrows in soft grass-covered slopes.
Experienced breeders are the first to appear, and often return to the same site they used the previous year. The females will leave the nesting site for approximately 14 days before laying, but the males will reappear at night keeping the nest hole free from snow.
One egg is laid in December, and hatches in late January to mid-February. The egg is incubated by both members of the pair for a total of 45 days. The male takes the first shift.
Departure of the chicks and adults occurs in mid-March, 45–55 days after hatching. Adults and fledglings move into subantarctic and temperate waters for the winter months, regularly reaching Australia.
Diet and feeding
Antarctic prion feed on euphausiids and other crustaceans, small cephalopods and polychaete worms. They feed by running along the surface of the water with wings outstretched and bill (or their entire head) submerged in the water to scoop their food. They also take larger individual prey from the surface in flight or while swimming. They occasionally make shallow dives to capture prey.
Feral cats and rats are major predators of adult Antarctic prion at breeding colonies. Skuas and gulls also capture adult prion at the breeding grounds by digging out their shallow burrows to obtain the eggs or young.