White-tailed tropicbird

Phaethon lepturus Daudin, 1802

New Zealand status: Native

Conservation status: Vagrant

Other names: white-tailed bosunbird, yellow-billed tropicbird, longtail, marlin-spike, whitetailed tropicbird, white tailed tropicbird

Geographical variation: A “gold morph” is most common in the north-east Indian Ocean. Western Pacific birds are the smallest form.

White-tailed tropicbird. Adult in flight. Ile Europa, Mozambique Channel, November 2008. Image © James Russell by James Russell

White-tailed tropicbird. Adult in flight. Ile Europa, Mozambique Channel, November 2008. Image © James Russell by James Russell

Tropicbirds are tern-like tropical seabirds, strongly associated with islands, that are charismatic on account of their long tails, and attention-drawing aerial displays. In New Zealand the white-tailed tropicbird is generally only found beach-wrecked, but it is a conspicuous species on many tropical Pacific islands.

Identification                                                               

The white-tailed tropicbird is a predominantly white seabird, slightly larger than a red-billed gull, with distinctive black markings on the upper wings and wingtips, and (in the adult) a long thin white tail that doubles the length of the bird. A bold black mark encloses the eye and extends back over the ear. The bill is yellow, and the small webbed feet are black. Juveniles have a grey bill, lack the long white tail, and are heavily barred black on the back and inner portions of the upperwing, with black bases to the outer primaries.

Voice: loud repeated “kek kek kek kek” in flight, and a rasping scream. Usually silent at sea.

Similar species: red-tailed tropicbirds are larger; as adults they have a red bill and tail streamers, and have predominantly white upper wings. Immature red-tailed tropicbirds are larger and more heavily barred than immature white-tailed tropicbirds, and have darker bills.

Distribution and habitat

White-tailed tropicbirds breed on tropical islands in all three oceans, and range widely over tropical seas, preferring waters with sea surface greater than 22° C. In the south-west Pacific they are typically found north of 21° south.

New Zealand records

About 20 white-tailed tropicbirds have been found beach-cast in New Zealand, all from the northern North Island, with the southernmost in Taranaki. Most were juveniles or immature, and most were found in summer.

Behaviour and ecology

White-tailed tropicbirds nest on tropical islands and atolls at high or low elevations. They use a wide range of nesting sites, including on the ground, cliff ledges and at tree bases. They may nest alone or in loose groups, breeding as monogamous pairs. Both adults incubate the single egg and feed the chick, and are generally faithful to previous nesting sites. White-tailed tropicbirds perform acrobatic display flights in pairs or small groups, with frequent calling. They feed by both plunge-diving and surface feeding, often with other species.

Food

Mostly fish and squid.

Website

http://en.wikipedia.org/wiki/White-tailed_Tropicbird

http://www.birdlife.org/datazone/speciesfactsheet.php?id=3650

References

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

Pratt, H.D.; Bruner, P.L.; Barrett, D.G. 1987. A field guide to the birds of Hawaii and the Tropical Pacific.Princeton University Press.

Recommended citation

McKinlay, G. 2013. White-tailed tropicbird. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz

White-tailed tropicbird

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White-tailed tropicbird

Breeding season
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Egg laying dates
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
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