Justification of Red List Category
This species has a very 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). The population trend appears to be stable, and hence the species does not 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.
The global population size has not been quantified, but this species is described as common (Lloyd 2020).
Due to the remoteness and inaccessibility of large parts of its range, the species's habitat is currently not considered under imminent risk. Tree cover loss within the range is negligible (<1% over ten years; Global Forest Watch 2021, using Hansen et al.  data and methods disclosed therein); moreover, the species appears able to tolerate considerable habitat disturbance (Lloyd 2020). Therefore, in the absence of evidence for any declines or substantial threats, the population is suspected to be stable.
Asthenes helleri has a restricted range in the Andes of Cusco and Puno, Peru, south to La Paz, Bolivia.
The species is mostly found between 2,700 and 3,700 m elevation. Above the timberline, this species occurs in páramo grassland and elfin forest. Below the timberline, it prefers dense undergrowth at the edge of cloud-forest, often with Chusquea bamboo stands; it appears to tolerate considerable habitat disturbance. Its diet consists of arthropods, taken from understorey foliage (del Hoyo et al. 2003, Lloyd 2020).
The primary threat to this species is the loss of its habitat through deforestation (Soares-Filho et al. 2006, Bird et al. 2011). It has probably always had a relatively small population, but it may be susceptible to the impacts of grazing and burning in its Andean timberline habitat (del Hoyo et al. 2003). Nevertheless, tree cover loss is currently negligible within its remote range (<1% over ten years; Global Forest Watch 2021, using Hansen et al.  data and methods disclosed therein), and the species is not considered under imminent risk.
Conservation Actions Underway
The species is found in several protected areas throughout its range, including Machu Picchu Historical Sanctuary and Manu National Park in Peru, and Madidi National Park in Bolivia.
Conservation Actions Proposed
Survey to produce an accurate estimate of the population size. Monitor the population trend.
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).
17-18 cm. Smallish, brown-and-grey ovenbird. Typical thistletail. Crown and upperparts, including wings, are a dull rufescent brown. The tail is paler, long and deeply forked. The underparts, including throat, are greyish. Voice A series of spluttering notes, first increasing in volume then fading at the end.
Text account compilers
Butchart, S., Ekstrom, J., Khwaja, N., Lees, A., Sharpe, C.J. & Symes, A.
BirdLife International (2023) Species factsheet: Asthenes helleri. Downloaded from http://www.birdlife.org on 28/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/03/2023.