The northern chestnut-tailed antbird, or Zimmer's antbird, is a species of bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Colombia, Ecuador, and Peru.
Region
Western Amazon Basin
Typical Environment
Occupies lowland humid rainforest in eastern Colombia, eastern Ecuador, and northeastern Peru. Prefers dense, shaded understory of terra firme and seasonally flooded (várzea) forests, including vine tangles and Heliconia or bamboo thickets. Often found along quiet stream margins and in the interior of mature forest, occasionally using older second growth if understory structure is intact. Typically forages within a few meters of the ground where cover is thick.
Altitude Range
Sea level to 900 m
Climate Zone
Tropical
Ease of Keeping
Beginner friendly: 1/5
The northern chestnut-tailed antbird, also known as Zimmer's antbird, is a shy understory specialist of the western Amazon. It often forages near army-ant swarms, snatching flushed insects from low perches or the leaf litter. Pairs maintain territories year-round and communicate with clear, whistled duets. Its rich chestnut tail contrasts strikingly with the otherwise darker body, aiding field identification in dim forest light.
Temperament
solitary and territorial
Flight Pattern
short rapid wingbeats, low to the ground
Social Behavior
Usually encountered as pairs that maintain territories throughout the year. Nests are placed low in dense understory; both sexes likely share incubation and chick-rearing duties. Frequently associates with army-ant swarms but also forages independently within thick cover.
Migratory Pattern
Resident
Song Description
Song is a clear, measured series of whistled notes that accelerates slightly and may descend at the end. Calls include sharp chips and soft contact notes exchanged between pair members.
Plumage
Male is slate-gray to dusky with a darker face and throat, contrasting rich chestnut rump and tail; female is warm brown to rufescent with paler underparts and the same chestnut tail. Both sexes show plain wings with minimal patterning and a slightly shaggy throat. Feathers appear smooth but can look sooty in low light.
Diet
Feeds primarily on arthropods such as insects and spiders, taken by gleaning from leaves, stems, and the forest floor. Will sally or pounce to the ground to seize prey flushed by movement or by army ants. Occasionally captures small invertebrates from rotting logs and leaf litter.
Preferred Environment
Forages in dense, shaded understory within mature rainforest, especially near vine tangles and along small streams. Regularly follows army-ant swarms when available, typically perching 0–2 m above the ground to grab fleeing prey.
