Thick-billed Siskin

Overview

The thick-billed siskin (Spinus crassirostris) is a species of bird in the family Fringillidae. It is currently assessed as Least Concern by the IUCN Red List.

Identification

• Males have a black head, neck, and throat with a thin yellow band, olive-yellow back, and bright yellow underparts.
• Females have a dark gray head and nape, greenish-olive upperparts, and dingy yellow underparts.
• Both sexes possess a notably thick bill and dark gray or blackish legs.
• The song is a rapid, low-pitched series of twitters, accompanied by wheezy calls.

Habitat

The species inhabits Polylepis woodlands, shrublands, brushy hillsides, and areas with stunted trees at elevations between 3,000 and 4,800 m. Its range is disjunct, covering parts of northwestern Peru, northern Chile, central Chile, northern Bolivia, and northwestern Argentina.

Diet

During the breeding season, the bird feeds almost entirely on the seeds, buds, and shoots of Polylepis, with a likely more varied diet in the non-breeding season. It forages acrobatically in trees, often hanging upside down on thin branches.

Did you know?

This bird is one of the larger members of its genus and possesses the eponymous thick bill that gives the species its name.