Yellow-rumped Siskin Spinus uropygialis Scientific name definitions

The Yellow-rumped Siskin is a dark siskin of the Andes. The sexes are similar, blackish overall with bright yellow on the rump, breast, and belly. The similar and sympatric Black Siskin (Carduelis atrata) has more black on the underparts and lacks the yellow rump. The Yellow-rumped Siskin is common in Chile, but rare further north in Peru where it apparently occurs only as a non-breeding migrant April through October. Individuals feed in small groups, occasionally including other siskin species, on the ground or in low vegetation in scrub on Andean slopes.

12–13 cm; 14 g (1 bird from Peru). Rather small, blackish-and-yellow finch with fine conical bill and notched tail. Male has head and upperparts to centre of breast sooty black (in fresh plumage, yellow fringes on hindneck to back and scapulars), rump bright yellow, uppertail-coverts blackish, broadly fringed yellowish; tail black, outer feathers broadly edged yellow at base (forming short panels); upperwing black, median coverts finely tipped yellow (soon worn away), greater coverts broadly tipped yellow, flight-feathers broadly bright yellow across bases of primaries and narrowly so across bases of secondaries, tertials narrowly fringed pale yellowish or whitish, underparts below breast bright yellow, tinged greenish on flanks; iris black; bill brown or dark brown; legs dark brown or black. Female is very similar to male, but head to breast and upperparts dull blackish-brown, broad olive-green fringes on mantle, back and scapulars, slightly paler yellow on rump and underparts. Juvenile is like female, but browner to buffish-grey with golden-buff wash on face, dark streaks on upperparts and on breast to flanks and belly.

• Hooded x Yellow-rumped Siskin (hybrid) Spinus magellanicus x uropygialis

Mostly plant seeds; occasionally some insects. Forages on the ground, in low vegetation and in bushes . In pairs and small groups; in non-breeding season occurs in larger gatherings, and in mixed-species flocks with other siskins.

Song poorly known, a rich and melodious series of warbling phrases interspersed with twitters and trills, delivery somewhat slower than that of congeners. Call a nasal "pheew".