The Christmas Island shearwater is a poorly known, relatively rare petrel species, with a widespread breeding distribution in the tropical and subtropical Pacific. Only two vagrants have been identified in New Zealand. The common name and the scientific name nativitatis reflect the species being named after a specimen from Christmas Island, now known as Kiritimati, in the Line Islands group.

Identification

The Christmas Island shearwater is an all-dark, medium-sized petrel, with blackish plumage and a dark under wing. It has a slightly wedge-shaped tail, a long thin black bill and dark feet. The Christmas Island shearwater has buoyant flight but it usually flies close to the sea surface with stiff wing-flapping and little soaring.

Voice: Christmas Island shearwater are silent at sea, and give plaintive sighs, whines and moans at the colony.

Similar species: several other all-dark (or nearly all-dark) petrels occur in New Zealand. The long thin bill of Christmas Island shearwater identifies it as belonging to the genus Puffinus, of which sooty shearwater, short-tailed shearwater and wedge-tailed shearwater share a dark bill. Christmas Island shearwaters are smaller than all these species and have completely dark feet. Also their relatively longer tail and entirely dark under wing distinguish them from sooty shearwaters and most short-tailed shearwaters, although even in Christmas Island shearwaters the under wing can appear silvery. Other all-dark petrels with dark, but more robust, bills include Kerguelen petrel (350 g), grey-faced petrel (550 g) and the very rare Bulwer’s petrel (94 g).

Distribution and habitat

All Christmas Island shearwater nesting colonies are on islands in the tropical and subtropical Pacific: Marshall, Johnston, Hawaiian, Phoenix, Line, Marquesas, Tuamotu, Samoan (possibly), Austral, Gambier, Oeno, Henderson, Ducie, Easter Islands and Isla Salas y Gomez. The Christmas Island shearwater is not known to migrate but its at-sea distribution is poorly understood .

New Zealand records

There are only two New Zealand records of Christmas Island shearwater. The first was a "well-dried corpse" found on Dargaville Beach in February 1976. The second was caught alive among wedge-tailed shearwaters on Curtis Island, in the Kermadec group, in November 1989. New Zealand is more than 2,000 km from the nearest breeding site, so these two birds were probably strays. There are no records of Christmas Island shearwater from Australia.

Behaviour and ecology

Christmas Island shearwaters are usually nocturnal ashore but can be active at colonies at all times of the day. Nests are usually in cavities or burrows in rocky areas or under vegetation. Breeding may occur year-round but some populations nest synchronously or in distinct seasons.

Food

The Christmas Island shearwater feeds by pursuit diving and plunging. Food is mainly squid with lesser amounts of fish. The bird caught on Curtis Island regurgitated the remains of 3-5 cm long fish.

Websites

BirdLife factsheet

Wikipedia

References

Brooke, M. 2004. Albatrosses and petrels across the world. Oxford University Press, Oxford.

Crockett, D.E. 1977. First record of the Christmas Island shearwater in New Zealand. Notornis 24: 285-286.

Dickinson, E.C. (ed.) 2003. The Howard and Moore complete checklist of the birds of the world. (3rd edn). Princeton University Press, Princeton.

Marchant, S.; Higgins, P.J. (eds) 1990. Handbook of Australian, New Zealand and Antarctic birds. Vol.1, ratites to ducks. Oxford University Press, Melbourne.

Taylor, G.A.; Tennyson, A.J.D. 1994. Christmas Island shearwater Puffinus nativitatis on Curtis Island. Notornis 41: 287-291.

Tennyson, A.J.D. 2010. Procellariiformes. Pp. 64-135. In: Checklist Committee (OSNZ) 2010. Checklist of the birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica (4th edn). Ornithological Society of New Zealand & Te Papa Press, Wellington.

Recommended citation

Tennyson, A.J.D. 2013. Christmas Island shearwater. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz