Narrow-billed Antwren Formicivora iheringi


Justification of Red List category
This species was formerly considered as Vulnerable. However, it is now known from more than ten locations and its population is believed to be moderately small (Collar et al. 1992). It also appears to tolerate some forest fragmentation, suggesting that population declines may not be as serious as previously suspected. It is consequently listed as Near Threatened.

Population justification
The global population size has not been quantified, but this species is described as 'uncommon' (Stotz et al. 1996).

Trend justification
A moderately rapid population decline is suspected, owing to rates of habitat destruction within the species's range. However, recent data on population size or trends are lacking.

Distribution and population

Formicivora iheringi is known from nine sites in eastern Bahia (Senhor do Bonfim, Iramaia, Novo Acre, Jagaquara, Boa Nova, Jacobina [R. Parrini and J. Minns in litt. 1999], Serrinha [B. M. Whitney per F. Brammer in litt 1998], south of Jequié and three localities in the Chapada Diamantina National Park [R. Parrini and J. Minns in litt. 1999, Parrini et al. 1999]) and eleven sites in north-east Minas Gerias (Almenara, Divisópolis, Pedra Azul and recently Araçauí, Botumirim, Turmalina, Fazenda São Miguel, Fazenda do Senhor Onofre Sandinha, Campo Limpo, Catutiba and Mendanha [E. O. Wiilis and Y. Oniki in litt. 1999, Neto et al. 2001, Vasconcelos et al. 2006]), east Brazil. Recent findings in Minas Gerias suggest a larger extent of occurrence than previously thought, and show the species is able to use several types of forest (Neto et al. 2001). Population size is not known, but the species is considered common at Boa Nova and around Vitoria da Conquista, where recent surveys found it common in all forest fragments visited, and it is described as relatively abundant at Aracuai and Botumirim.


It typically inhabits tropical deciduous and semi-deciduous forest (250-1,050 m) (del Hoyo et al. 2003), apparently favouring mata-de-cipó interiors with vine-tangles and patches of terrestrial bromeliads. It forages for invertebrates singly or in pairs, sometimes with flocks, generally 3-8 m above the ground (Ridgely and Tudor 1994).


Its habitats are being rapidly cleared for cattle pasture in central-south Bahia, and much of the forest in north-east Minas Gerais and adjacent south Bahia has been cleared for coffee plantations. At Aracuai, tourmaline miners have disturbed all caatinga vegetation (Neto et al. 2001). Natural habitats are reduced to hilltops around Boa Nova (Whitney 1996b), and remaining forest patches are highly disturbed by livestock and subject to local exploitation of trees for firewood and fenceposts (Tobias et al. 1993). However, observations at Boa Nova suggest it is able to cope with forest fragmentation, persisting in small areas.

Conservation actions

Conservation Actions Underway
It occurs in the Acaua Ecological Station protected area, Minas Gerais, Brazil (Neto and de Vasconcelos 2004). The species is protected under Brazilian law.

Conservation Actions Proposed
Designate a forest reserve of mata-do-cipó in conjunction with an experimental agricultural station or as a community-level conservation initiative (Tobias et al. 1993). Research its precise ecological requirements, with particular reference to levels of tolerance of secondary, disturbed or fragmented habitats. Investigate the feasibility of protecting forest patches at Boa Nova. Conduct further surveys to locate additional sites for the species.


11.5 cm. Long-tailed, arboreal antwren. Male slate-grey. Black wings, with two white wing-bars and white spotting on shoulder. Narrow white tips to outer rectrices. Grey underparts, with black bib extending to mid-breast. Silvery-white flanks. Female olive-brown above and more rufescent on uppertail-coverts. Dusky wings and tail, with two indistinct, buff wing-bars. Ochraceous underparts, palest on throat with limited white on flanks. Similar spp. White-flanked Antwren Myrmotherula axillaris luctuosa is shorter tailed and female has less rufescent uppertail-coverts and less uniform ochre underparts. Apparently not sympatric. Voice Male song is musical series of 7-12 (2 per second) metallic píeep notes. Female gives shorter, softer version.


Text account compilers
Butchart, S., Gilroy, J., Sharpe, C J

Willis, E., Oniki, Y., Minns, J., Parrini, R., Whitney, B., Brammer, F.

Recommended citation
BirdLife International (2023) Species factsheet: Formicivora iheringi. Downloaded from http://datazone.birdlife.org/species/factsheet/narrow-billed-antwren-formicivora-iheringi on 11/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 11/12/2023.