South Georgia diving petrel

South Georgia diving petrel
File:Pelecanoides georgicus (South Georgian diving-petrel) (8365384976).jpg
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Procellariiformes
Family:	Pelecanoididae
Genus:	Pelecanoides
Species:	P. georgicus
Binomial name
Pelecanoides georgicus Murphy & Harper, 1916

The South Georgia diving petrel or Georgian diving-petrel (Pelecanoides georgicus) is a diving petrel, one of four very similar auk-like small petrels of the southern oceans. It is native to south Atlantic and islands of the southern Indian Ocean, islands and islets off New Zealand and south-eastern Australian islands.

Taxonomy and systematics

The American ornithologist Robert Cushman Murphy and his partner Harper described the South Georgia diving petrel in 1916. Its specific name georgicus is derived from the name of the islands were on when they identified the species: South Georgia. Alternate common names include: Puffinure de Géorgie du Sud (in French), Breitschnabel Lummensturmvogel (in German), and Potoyunco de Georgia (in Spanish).

Description

The South Georgia diving petrel is a small, plump petrel, 180 to 220 mm (7.1–8.7 in) in length and weighing around 90 to 150 g (3.2–5.3 oz). The plumage is black above and dull white below and it has a large black bill. The wings have thin white strips. The face and neck can be more brown than black. The legs are blue. Unless seen very close, it is almost indistinguishable from the common diving petrel. The common petrel has brown inner web primary feathers, whereas the South Georgia petrel has light inner web feathering. Common petrels have smaller and narrower bills than the South Georgia petrel. Another difference is that the South Georgia diving petrel has a posterior black line down the tarsi. There are also slight size differences.

Distribution and habitat

It nests in colonies on Subantarctic islands. It breeds on South Georgia in the south Atlantic and on the Prince Edward Islands, Crozet Islands, Kerguelen Islands and Heard Island and McDonald Islands in the southern Indian Ocean. In New Zealand, it breeds on Codfish Island and formerly bred on the Auckland Islands. It disperses to surrounding seas and vagrants have been recorded in the Falkland Islands and Australia. While 1.5 m (4.9 ft) nests are usually built on vegetated slopes, they are occasionally built on flatland.

Behaviour

File:Puffinure de Géorgie MHNT.jpg

Pelecanoides georgicus

The South Georgia diving petrel feeds primarily on planktonic crustaceans, particularly krill, but will also feed on small fish and young cephalopods. Breeding season is October–February. The female lays one egg that is incubated for 44–52 days. Fledging occurs in 43–60 days. Threats to the South Georgia diving petrel include skuas, cats, rats, and weka. They are extinct on Auckland Island because Hooker's sea lions destroyed their nests. South Georgia diving petrels are noted for their diving capabilities. "The most proficient divers of the order Procellariformes are likely to be the diving petrels in the family Pelecanoididae." Dive depths for the South Georgia diving petrel have been recorded to 48.6 m (159 ft), with most in the range of 20.4 to 24.4 m (67–80 ft).