• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Justification of Red List category
This species has a small population, which is scattered in isolated subpopulations, and is declining as a consequence of continued habitat loss and fragmentation. For these reasons it is evaluated as Vulnerable.

Population justification
Based on extensive surveys across the range, it is estimated that the population numbers less than 10,000 mature individuals (ICMBio 2018). It is here placed in the band 2,500-9,999 mature individuals.
The species is restricted to isolated forest fragments and observational records are scattered across the range (ICMBio 2018, eBird 2022). It appears sensitive to habitat disturbance and avoids early successional growth and therefore is likely unable to disperse between occupied forest patches. Based on its disjunct range, it is therefore assumed that it forms at least 15 separate, small subpopulations.

Trend justification
There are no data on the population trend. However, the species has become locally extinct in recent years in several areas (ICMBio 2018). It is estimated that the total area of occupancy declined by 25% over 15 years (ICMBio 2018). As the species is rare and confined to small, isolated subpopulations in disjunct patches of forest, it is inferred that the population declines are continuing on the basis of reductions in forest cover and increasing fragmentation between populations.
Within the range, 8% of tree cover is lost over ten years (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). As patches of suitable habitat are scattered and isolated, population declines may exceed the rate of tree cover loss due to the additional impact of habitat fragmentation. Tentatively, population declines are here placed in the band 10-19% over ten years. This value is confirmed by the reported declines in the area of occupancy, which correspond to 17% over ten years.

Myrmotherula urosticta occurs in the Atlantic forest of east Brazil. It is known from a limited number of isolated localities from Bahia south to Rio de Janeiro.

It inhabits the lower growth and mid-layer of primary or moderately disturbed coastal Atlantic forest (Zimmer et al. 2020). It prefers areas with dense, tangled vines and taller forests with sandy sold and a variable dry season (Whitney and Pacheco 1995). It is less common in second growth with a canopy height of less than 15-20 m. It is encountered almost exclusively with mixed-species flocks, foraging for insects from 3-9 m above ground, mostly 5-7 m, in live vegetation and vines (Whitney and Pacheco 1997). Its ecology is however not well known.

Virtually all lowland Atlantic forest outside protected areas has been cleared within its historical range, and even some of the protected areas in which it occurs are not secure (Whitney and Pacheco 1995). Its habitats are historically threatened by agricultural conversion and deforestation for mining and plantation production, and current key threats are urbanisation, agricultural expansion, colonisation and associated road-building (Dinerstein et al. 1995, Fearnside 1996, ICMBio 2018).

Conservation Actions Underway
The species occurs in several protected areas, including Serra das Lontras, Descobrimento, Monte Pascoal, Pau Brasil and Tijuca national parks (ICMBio 2018). It is included in a multi-species action plan for Atlantic forest birds (ICMBio 2018).

Conservation Actions Proposed
Carry out surveys to ascertain trend rates. Research the species' ecology. Monitor the population trend. Monitor rates of habitat loss.
Ensure de facto protection of existing reserves. Consider restoring degraded habitat, with the aim of creating dispersal corridors to facilitate movement and gene flow between subpopulations. Hire, train and maintain park guards from local communities. Actively pursue all measures to stimulate environmental awareness in communities near reserves.

9.5 cm. Small, pale, relatively long-tailed antwren. Male plumbeous. Black wings with two bold white wing-bars. Black tail with broad white terminal band. Underparts paler with black bib. Female similar, but paler above. Grey wings with whitish wing-bars, creamy-buff underparts, whitish on throat and greyish on flanks. Similar spp. Tail-band is distinctive. Sympatric White-flanked Antwren M. axillaris luctuosa can show white tip to tail, but never as extensively. Also much darker with less contrasting bib. Voice Nasal descending beer bin.

Text account compilers
Hermes, C.

Contributors
Benstead, P., Capper, D., Clay, R.P., De Luca, A., Develey, P., Lima, P.C., Sharpe, C.J. & Symes, A.

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Recommended citation
BirdLife International (2024) Species factsheet: Band-tailed Antwren Myrmotherula urosticta. Downloaded from https://datazone.birdlife.org/species/factsheet/band-tailed-antwren-myrmotherula-urosticta on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.