The thick-billed siskin (Spinus crassirostris) is a species of finch in the family Fringillidae. Found in Argentina, Bolivia, Chile, and Peru, its natural habitats are subtropical or tropical moist montane forests and subtropical or tropical high-altitude shrubland.

Description

The thick-billed siskin has an adult length of between 13.5 and 14 cm. The bill often has a silvery base and is noticeable thicker than other related siskins. The male closely resembles the hooded siskin (Spinus magellanicus) and has a black head and throat, greenish-yellow upper parts (sometimes streaked with dark markings) and bright yellow underparts. It differs from the hooded siskin in having a whitish-grey midbelly. The immature male has a black head but is otherwise less conspicuous than the mature male, being more greyish-olive above and greyish below. The female is similar but lacks the black head and is altogether much duller in appearance, more greyish-olive, with paler underparts.

Distribution and habitat

This bird of the high Andes ranges from western Peru and central Chile to northwestern Argentina. Its altitudinal range is 3000 to 4000 m in the northern part of its range but descends to 2100 m further south. Typical habitat is Polylepis woodland and open country with scrub.

Status

S. crassirostris is an uncommon species with a patchy distribution within its range. However, it has a very wide range and the population seems stable so the International Union for Conservation of Nature has rated it as being a least-concern species.