Characterized by its intricate streaked plumage and remarkable architectural abilities, this medium-sized passerine of the Furnariidae family is a unique representative of its genus. This species, scientifically known as Anumbius annumbi, measures approximately 7 to 8 inches (18 to 20 centimeters) in length. It displays a grayish-brown dorsal coloration heavily streaked with dark brown tones, contrasting with pale buffy-white underparts that shade into a warmer ochre color along the flanks. A key diagnostic feature is its stark white throat, which is neatly bordered by a necklace of delicate black spots. The tail is relatively long and graduated, showing pointed central feathers and outer feathers tipped with conspicuous white spots, easily visible during flight. Its bill is straight, stout, and pale horn-colored.
Geographical distribution: This species is widely distributed across the southern cone of South America. Its range encompasses the central and northern regions of Argentina, the entire territory of Uruguay, the southernmost states of Brazil (specifically Rio Grande do Sul), and the southeastern portion of Paraguay.
Habitat: It primarily frequents open and semi-open landscapes, including temperate grasslands, shrubby savannas, agricultural fields, pastures, and roadside edges. It shows a strong preference for areas scattered with thorny bushes and isolated trees, demonstrating an outstanding ability to thrive in human-modified environments.
Feeding: Its diet is predominantly insectivorous, consisting of a wide range of beetles, ants, larvae, spiders, and other small terrestrial invertebrates. It searches for prey by walking deliberately on the ground, using its strong bill to flip leaves, probe the soil, and extract hidden insects from low vegetation.
Behavior: Typically encountered in pairs or small family units, this bird moves with an upright posture and a jaunty gait. Its flight is low, short, and undulating. It is highly vocal, frequently delivering a loud, harsh series of metallic trills and rapid chips, often performed as a synchronized duet by mated pairs. It is a highly active and territorial species, spending a significant portion of its day gathering building materials.
Nesting: It is celebrated for constructing an incredibly large, conspicuous nest made entirely of thorny twigs and dry branches, which explains its common name, the firewood-gatherer. This massive dome-like structure, sometimes reaching up to 3 feet (1 meter) in height, is situated on telephone poles, fence posts, or solitary trees. The interior features a winding entrance tunnel leading to a well-insulated nesting chamber. The female lays a clutch of 3 to 5 white eggs, which are incubated by both parents for about 16 to 18 days. Due to their durability, these formidable stick structures are highly coveted and frequently reused by various other birds, mammals, and reptiles once vacated.
Conservation status: It is classified as Least Concern (LC) on the IUCN Red List. The species maintains a stable population and has even expanded its range in some areas due to agricultural activities that create the open, shrubby habitats it prefers.
Compilation and publication: EcoRegistros – 23/07/2026