Weihnachtsinselsalangane

Bestimmung

The Christmas Island swiftlet is a small swiftlet some 9–11 cm (3.5–4.3 in) in length. It is mainly glossy blue-black or green-black above, with dark grey underparts relieved by a prominent white belly and vent.

Taxonomie

The Christmas Island swiftlet was described by the English naturalist Joseph Lister in 1889 with the scientific name Collocalia esculenta natalis. It has usually been considered a subspecies of the glossy swiftlet (Collocalia esculenta). However, in 2008 the taxonomists Les Christidis and Walter Boles treated the swiftlet as a subspecies of the cave swiftlet (Collocalia linchi). It was raised to species status based on a detailed analysis of the swiftlets in the genus Collocalia published in 2017.

Wissenschaftlicher Name

Collocalia natalis

Autorität

Lister, 1889

Ordnung

Apodiformes

Familie

Apodidae

Gattung

Salanganen

Verbreitung und Lebensraum

This swiftlet is restricted to the 135 km2 Christmas Island where it is commonly seen in large numbers in flight above the tropical rainforest that covers 75% of the island, as well as over other terrestrial habitats there. It nests mainly in caves in the limestone cliffs surrounding the island.

Verhalten

Diese Salangane brütet tief im Inneren von Höhlen, bei fast vollständiger Dunkelheit. Für ihr Gelege aus zwei Eiern baut sie ein kleines napfförmiges Nest hoch an der Höhlenwand, oft im Schutz eines Stalaktiten. Die Nester bestehen aus getrockneten Palmfasern und Flechten und werden mit Speichel an der Höhlenwand befestigt.<p>Die Salangane erbeutet fliegende Ameisen und andere Insekten in der Luft.

Schutzstatus

Garnett &amp; Crowley (2000) considered the swiftlet, along with a suite of Christmas Island's other endemics, as critically endangered, with the principal threat coming from the yellow crazy ants which were accidentally introduced to the island. The threat is not only that of direct ant predation of swiftlet nestlings, but also indirectly from potentially massive changes to the ecology of the island caused by the ants. Sometimes the bird breeds in hollow trees and these nests are susceptible to attack by the ants, but the ants do not enter the limestone caverns that are the principle breeding site and are not therefore likely to impact directly on the swiftlet. An application made in 2006 to list the swiftlet as threatened under the Environment Protection and Biodiversity Conservation Act 1999 was unsuccessful.