Courlis d'Alaska

Identification

The bristle-thighed curlew has a long, decurved bill and bristled feathers at the base of the legs. Its length is about 40–44 cm and wingspan about 84 cm (females averaging bigger than males). The size and shape are the same as the whimbrel's, and the plumage is similar, spotted brown on their upper body with a light belly and rust-colored or buffy tail. The bigger buff spots on the upper body, unmarked light belly and barely marked flanks, tail color, and pale buffy-orange rump distinguish it from the whimbrel.

Taxonomie

The bristle-thighed curlew was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it in the genus Scolopax and coined the binomial name Scolopax tahitiensis. Gmelin based his description on the "Otaheite curlew" that had been described in 1785 by the English ornithologist John Latham in his A General Synopsis of Birds. "Otaheite" is a former name of Tahiti. The specimen used by Latham was supplied by the naturalist Joseph Banks. Banks had accompanied James Cook on his first voyage to the south Pacific but had also received specimens from Cook's subsequent voyages. The bristle-thighed curlew is now one of nine species placed in the genus Numenius that was erected in 1760 by the French scientist Mathurin Jacques Brisson in his Ornithologie. The name Numenius is from Ancient Greek noumenios, a bird mentioned by Hesychius. It is associated with the curlews because it appears to be derived from neos, "new" and mene "moon", referring to the crescent-shaped bill. The species is considered to be monotypic: no subspecies are recognised.

Nom scientifique

Numenius tahitiensis

Autorité

(Gmelin, JF, 1789)

Ordre

Charadriiformes

Famille

Scolopacidés

Genre

Numenius

Répartition et habitat

Its winter habitat is tropical Oceania, and includes Micronesia, Fiji, Tuvalu, Tonga, Hawaiian Islands, Samoa, French Polynesia and Tongareva (Penrhyn atoll). There is concern over encroachment and introduced predators in their winter habitat.<p>Although it was described after James Cook's visits to Tahiti in the 18th century, its breeding area was not identified until 1948. Nesting grounds are on the lower Yukon River and Seward Peninsula, with the birds preferring low-lying tundra near the shoreline. The bird is rarely seen near populated land masses, with only a handful of sightings in Canada, California and Oregon.

Aire de reproduction

NA : low Arctic upland tundra of w Alaska: nc Seward Pen. and n Yukon Delta

Aire hors reproduction

c, s PO is. : Micronesia and Fiji (sw Polynesia) e through Northwestern Hawaiian Is. and Kaui (rarer on other main Hawaiian Is.) and all Polynesian islands; rarer to Japan and Melanesia

Migration

Migrateurs complets

Comportement

Mode de migration: Migrateurs complets.

Conservation

Tendance de la population: en déclin.

Tendance de la population

en déclin