cineracea, northeastern Ecuador, northeastern Peru, and western Brazil south of the Amazon N. r. simplex, northern Brazil south of the lower Amazon N. r. rubecula, eastern and southeastern Brazil, eastern Paraguay, and northeastern Argentina The rusty-breasted nunlet primarily inhabits humid terra firme and várzea forest, and is also found in secondary forest and forest edges. It can be found at any level within the forest but is most often in the midstory. In Venezuela it is usually found in areas of sandy soil; in southeastern Brazil's Paraná state it occurs in gallery forest, and in upper Amazonia it shuns igapó forest. Behavior Feeding The rusty-breasted nunlet's diet is reported to include large arthropods, both adult and larval. The nunlet occasionally briefly joins mixed-species foraging flocks. Breeding The rusty-breasted nunlet was thought to nest in a burrow, but a 2020 publication revealed that it nests in a shallow scrape on sloping ground that it roofs with twigs and leaves. Over a seven year period the authors studied 17 nests in Agentina's Misiones Province; they were in various stages of construction and use when discovered. Most clutches were of four eggs though one had three. Both sexes incubated the eggs and brooded and fed the nestlings. Vocalization The rusty-breasted nunlet's song is "a mewing series of 'weeip, weeip, weeip' notes (up to 20) that rise in both pitch and volume". It does not sing often. Status The IUCN has assessed the rusty-breasted nunlet as being of Least Concern. It has an extremely large range but its population is unknown and believed to be decreasing. Its apparent density varies from rare to rather common in various parts of the range, though it might be undercounted due to its unobtrusive behavior. It occurs in several protected areas. References External links Rusty-breasted nunlet photo gallery VIREO rusty-breasted nunlet Birds of the Amazon Basin Birds of the Guianas Birds of Brazil Birds of the Cerrado Birds of Paraguay rusty-breasted nunlet Taxonomy articles created by Polbot