The grey-bellied spinetail is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Brazil, Paraguay, and Uruguay.
Region
Southern South America
Typical Environment
Occurs from southeastern Brazil through eastern Paraguay and northeastern Argentina to Uruguay, favoring the Atlantic Forest fringe, riparian woodlands, and scrubby edges. It is most often found in dense understory, capoeira (second growth), bamboo patches, and riverine thickets. The species tolerates disturbed habitats and frequently uses hedgerows and brushy pastures near forest remnants. Within its range it is generally local to fairly common where suitable cover is present.
Altitude Range
0–1500 m
Climate Zone
Subtropical
Ease of Keeping
Beginner friendly: 1/5
A furtive understory furnariid, the grey-bellied spinetail keeps its long, rufous tail cocked as it creeps through dense thickets. Like many spinetails, it builds a bulky, ball-shaped stick nest with a side entrance tunnel. Pairs often duet with fast, rattling notes and may join mixed-species flocks along forest edges. It thrives in secondary growth and riparian scrub, which has helped keep its populations stable in much of its range.
Illustration from Nouveau recueil de planches coloriées d'oiseaux, 1838
Temperament
solitary and territorial
Flight Pattern
short rapid wingbeats
Social Behavior
Usually found singly or in pairs that maintain territories year-round. Pairs cooperate in building a bulky, enclosed stick nest with a lateral entrance tunnel placed low in dense shrubs or vines. It forages close to the ground up to the midstory and may accompany mixed-species flocks along edges.
Migratory Pattern
Resident
Song Description
Song is a fast series of dry, rattling notes that accelerates slightly, often delivered as a duet by the pair. Calls include sharp chips and trills given from inside cover. Vocalizations carry surprisingly well despite the bird’s secretive habits.
Plumage
Warm brown upperparts with a contrasting grey throat and belly, and a long, graduated rufous tail. Wings are brown with rufous tones; underparts otherwise dull grey to grey-brown with subtle shading. The feathering is plain rather than boldly patterned, aiding camouflage in dense cover.
Diet
Primarily takes small arthropods such as insects and spiders gleaned from leaves, twigs, and vine tangles. It probes into dead foliage and stick piles, and occasionally hawks short distances for flushed prey. There is little evidence of fruit or seed consumption, making it a largely insectivorous furnariid.
Preferred Environment
Feeds in dense, brushy cover along forest edges, riparian thickets, secondary growth, and bamboo. Most foraging occurs from near ground level to the lower midstory where cover is thick and tangled.
