Tristandrossel

Bestimmung

The bird was described by John Gould as being similar in size and appearance to the song thrush, and by Henry Moseley as like a very dark-coloured song thrush. However, it also has the short rounded wings and reduced keel indicative of a reduced need for flight, typical of bird species adapted to life on small islands.<p>This thrush typically has a length of about 22 cm (8.7 in). The nominate subspecies from Tristan differs from that from Nightingale Island, with the Tristan birds being warm dark brown on the upperparts rather than dull sooty-brown, rufous rather than dark fuscous on the sides of the head, and rufous-brown, rather than brownish-black, on the underparts. Birds from Inaccessible Island appear to be intermediate, with the sides of the head of a specimen from there speckled both rufous and fuscous.

Taxonomie

The thrush is thought to have evolved from an ancestor in the genus Turdus from South America, and resembles an immature austral thrush, but its adaptations to life on a small island group, including an unusual brush-tipped tongue modified for extracting the contents of eggs, have been used as reasons to warrant its separation into the monotypic genus Nesocichla. However, molecular analysis has indicated that not only is it part of a South American clade of Turdus, but also that it falls squarely within that genus.<p>There are three subspecies, the ranges of which correspond to the three main islands in the group:

Wissenschaftlicher Name

Turdus eremita

Autorität

(Gould, 1855)

Ordnung

Passeriformes

Familie

Turdidae

Gattung

Turdus

Verbreitung und Lebensraum

The thrush is found on Tristan, Inaccessible, Nightingale, Middle and Stoltenhoff Islands in the Tristan group. It uses all the natural habitats available on the islands, including rocky shorelines, tussock grassland, fern-dominated shrubland and wet heathland.

Zugverhalten

Standvogel

Verhalten

Zugverhalten: Standvogel.

Schutzstatus

Bestandstrend: stabil.

Bestandstrend

stabil