- Macronectes halli
Identification
aka Northern Giant Petrel (Macronectes halli)
Giant Petrels are the size of small albatrosses but distinguished by shorter wings, bulkier bodies and heavier, less graceful flight. However, the two species are very difficult to separate at sea and birds with intermediate characters are known to occur in some areas. Adult: largely greyish-brown above flecked with black, brown and white, slightly paler below with darker collar below whitish throat. Head whitish with heavy grey-brown mottling on crown and nape giving a distinct capped effect. Underwing grey-brown with dark leading edge and silvery-grey on bases of secondaries and inner primaries. Iris pale grey, bill horn-coloured with reddish tip, legs blackish or grey. Immature: juvenile is darker than adult, largely glossy-black developing white face and capped appearance with age. Closely resembles Southern Giant Petrel M. giganteus which differs in less capped effect of head, whiter breast, white leading edge to wing and horn-coloured bill with greenish tip.
Length 81-94cm. Wingspan 180-200cm.
Distribution
Southern Oceans breeding on Prince Edward, Marion, Crozet, Lerguelen, Macquarie, Chatham, Stewart, Auckland, Antipodes and Campbell Islands. Disperse widely to reach Australia and South Africa, mainly on the western coast but probably not reaching as far north as Southern Giant Petrel M. giganteus.
Taxonomy
Habitat
Breeds singly or in small loose colonies on remote islands, some remain at breeding sites throughout year others disperse to sea. Follows ships regularly and attracted to whale carcasses and seal colonies.
Behaviour
Voice: Hoarse croaks and grunts but slightly higher-pitched than Southern Giant Petrel. Squabbles noisily over carrion. A laughing hu-hu-hu-hu. Squabbles noisily over carrion.
Breeding: Breeds July-February, nest is a depression surrounded by dry vegetation. Single white egg (102 x 61mm).
Diet: Scavenges on mammal carcasses and around seabird colonies. Also takes squid and fish from sea surface and kills smaller birds.
