Phaéton à bec jaune

Identification

The adult white-tailed tropicbird is a slender, mainly white bird, 71–80 cm long including the very long central tail feathers, which double its total length. The wingspan is 89–96 cm. The bird has a black band on the inner wing, a black eye-mask, and an orange-yellow to orange-red bill. The bill colour, pure white back and black wing bar distinguish this species from the red-billed tropicbird.<p>The white-tailed tropicbird breeds on tropical islands, laying a single egg directly onto the ground or a cliff ledge. It disperses widely across the oceans when not breeding, and sometimes wanders far. It feeds on fish and squid, caught by surface plunging, but this species is a poor swimmer. The call is a high screamed keee-keee-krrrt-krrt-krrt. Sexes are similar, although males on average are longer tailed, but juveniles lack the tail streamers, have a green-yellow bill, and a finely barred back. The white-tailed tropicbird does not have a yearly breeding cycle; instead, breeding frequency depends on the climate and availability of suitable breeding sites. The bird can reproduce 10 months after the last successful breeding, or 5 months after an unsuccessful one.

Taxonomie

French zoologist François Marie Daudin described the white-tailed tropicbird in 1802.<p>"White-tailed tropicbird" has been designated the official name by the International Ornithologists' Union (IOC).<p>Its closest relative is the red-tailed tropicbird (P. rubricauda), the split between their ancestors taking place about four million years ago.<p>Six subspecies are recognised by the IOC:

Nom scientifique

Phaethon lepturus

Autorité

Daudin, 1802

Ordre

Phaethontiformes

Famille

Phaethontidae

Genre

Phaethon

Répartition et habitat

Breeding range: TrO : widespread all tropical oceans (except e Pacific and ne Atlantic). Non-breeding range: pelagic; to waters off e Africa, w, s Sri Lanka (w, n Indian Ocean), Indonesian Arch. and New Guinea waters, ec Australia (sw South Pacific) and Gulf Stream n to North Carolina (w North Atlantic).

Aire de reproduction

TrO : widespread all tropical oceans (except e Pacific and ne Atlantic)

Aire hors reproduction

pelagic; to waters off e Africa, w, s Sri Lanka (w, n Indian Ocean), Indonesian Arch. and New Guinea waters, ec Australia (sw South Pacific) and Gulf Stream n to North Carolina (w North Atlantic)

Migration

Migrateurs complets

Comportement

Mode de migration: Migrateurs complets.

Conservation

Tendance de la population: en déclin.

Tendance de la population

en déclin