Data Zone
Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Population justification
The global population size has not been quantified, but this species is described as uncommon or rare and patchily distributed (Stotz et al. 1996, Ridgely and Tudor 2009, Zimmer et al. 2020). It may however be overlooked due to its secretive behaviour.
Trend justification
There are no data on the population trend, but declines are suspected on the basis of ongoing deforestation.
Within the range, 4% of tree cover has been lost over the past ten years; since 2017 this has been accelerating to a rate equivalent to 5% over ten years (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). Due to its strict forest dependence and susceptibility to forest loss, fragmentation and degradation, population declines may exceed the rate of tree cover loss. They are therefore here placed in the band 1-19% over ten years.
Herpsilochmus axillaris along the east Andes of north-western South America. Subspecies senex occurs in Colombia, from Antioquia south as far as Cauca. Subspecies equatorialis occurs from Caqueta in Colomia through Ecuador to northern Cajamarca in Peru. This taxon is isolated from subspecies puncticeps by the río Marañón; the latter ranges from there south to Junín. The nominate subspecies axillaris ranges from Cuzco to Puno and likely adjacent northern Bolivia.
This is a subcanopy species of humid montane forest and forest borders. It forages on arthropods in the crown of subcanopy trees and the tangled growth of the mid-storey, often as part of mixed-species flocks (Zimmer et al. 2020). Its ecology is not well known.
The primary threat to this species is accelerating deforestation for logging and agriculture (Zimmer and Isler 2003, Soares-Filho et al. 2006, Bird et al. 2011). It is considered highly sensitive to human disturbance and as such is likely to suffer acutely as a result of forest fragmentation (Zimmer and Isler 2003, A. Lees in litt. 2011).
Conservation Actions Underway
The species occurs in several protected areas across its range, including Tatamá National Park in Colombia, Podocarpus and Sumaco Galeras National Parks in Ecuador, and the Manu National Park and Biosphere Reserve in Peru (Zimmer et al. 2020). It is listed as Near Threatened at the national level in Ecuador (Freile et al. 2019).
Conservation Actions Proposed
Quantify the population size. Research the species' ecology and behaviour. Monitor the population trend. Monitor rates of habitat loss.
Expand the protected area network to effectively protect key sites. Effectively manage protected areas, utilising emerging opportunities to finance protected area management with the joint aims of reducing carbon emissions and maximizing biodiversity conservation. Incentivise conservation on private lands through expanding market pressures for sound land management and preventing forest clearance on lands unsuitable for agriculture (Soares-Filho et al. 2006).
11-12 cm. Smallish, sexually dimorphic antwren. Males are grey above, with a black cap spotted white, a black eyestripe, black wing-coverts with white tips and pale underparts. Female is olive-buff above, with a cinnamon-rufous cap, less marked eyestripe and a more olive-tinged breast. Voice A rattle-like trill of dry notes.
Text account compilers
Hermes, C.
Contributors
Butchart, S., Ekstrom, J., Khwaja, N., Lees, A., Sharpe, C.J. & Symes, A.
Recommended citation
BirdLife International (2024) Species factsheet: Yellow-breasted Antwren Herpsilochmus axillaris. Downloaded from
https://datazone.birdlife.org/species/factsheet/yellow-breasted-antwren-herpsilochmus-axillaris on 22/12/2024.
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 22/12/2024.