Белохвостый гаучо Agriornis albicauda

Scarce and local in open and semiopen habitats of the high Andes, where it usually greatly outnumbered by similar Black-billed Shrike-Tyrant. Both species have mostly white tail (obvious in flight) and are best separated by bill size: White-tailed Shrike-Tyrant has a stout bill that is pale below compared with the slender, dark bill of Black-billed Shrike-Tyrant. These species can occur side-by-side and have similar habits, perching on prominent lookouts but then disappearing easily; both run well on the ground and often fly long distances.