The Black-billed Shrike-Tyrant bird is a small passerine bird found in the high Andes Mountains of South America. This species belongs to the family Tyrannidae, which is known for their insectivorous diet and distinctive vocalizations. The Black-billed Shrike-Tyrant bird is primarily found in mountainous habitats, including grasslands, shrublands, and rocky slopes at elevations ranging from 1,900-4,300 meters above sea level.
This bird is characterized by its distinctively large head and stout bill that is entirely black, which is how it derives its name. The bird's plumage is mostly greyish-brown on the upperparts, rump, and white ventrally. The wings and tail are darker, while the throat, chin, and chest areas are paler in color, giving them a kind of whitish appearance. The female bird has similar plumage to the male, but its head is generally smaller, and it has slightly duller colors.
The Black-billed Shrike-Tyrant bird feeds on a variety of insects, including beetles, grasshoppers, and flies, which it captures by sallying out from a perch to catch its prey mid-air. The bird's hunting behavior is swift and agile as it flies low over the ground in the open spaces or jumps from perch to perch to capture prey. The bird's voice is also characteristic, being a shrill, descending whistle that is repeated several times.
The Black-billed Shrike-Tyrant bird is monogamous, and the breeding season occurs from October to January. The bird typically builds its nest on or near the ground, in a shrub or tussock, using grass and other plant materials. The female lays two to three eggs, which are white or yellowish with brown speckles, and incubates them for about 16 days. Both parents feed the chicks and protect the nest from predators until the young ones are ready to leave the nest around two weeks after hatching.
The Black-billed Shrike-Tyrant bird is considered a species of least concern by the International Union for Conservation of Nature (IUCN). However, its populations are declining due to habitat loss caused by human activities such as agriculture and pastoralism. Conservation efforts such as habitat protection and restoration are necessary to ensure the survival of this unique Andean bird species.