Vilcabamba Spinetail Cranioleuca weskei


Justification of Red List Category

Although this species may have a restricted range, it is not believed to 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 population size has not been quantified, but the species is described as uncommon to locally fairly common (del Hoyo et al. 2020).

Trend justification
The population trend has not been estimated directly. The only threat known to the species is forest loss; however, deforestation over the past ten years has been low within the range (2%; Global Forest Watch 2020). Given that the species is restricted to montane and elfin forest, it can precautionarily be suspected that population declines are exacerbated by habitat degradation and will exceed the rates of forest loss alone. Nevertheless, it is unlikely that the rate of population decline surpasses 10% over ten years.

Distribution and population

Cranioleuca weskei is endemic to Cuzco, Peru, where it occurs from the Cordillera Vilcabamba in Cusco north to Ayacucho and Junín. It is present in the Machu Picchu Historical Sanctary.


It inhabits humid montane and elfin forest at elevations of 2,400-3,500 m (del Hoyo et al. 2003). It is often found in Chusquea bamboo and feeds on arthropods (del Hoyo et al. 2003).


The primary threat to this species is deforestation, as it is feared to be susceptible to forest fragmentation and edge effects.

Conservation actions

Conservation Actions Underway
The species occurs in the Machu Picchu Historical Sanctuary.

Conservation Actions Proposed

Expand the protected area network to effectively protect IBAs. Effectively resource and manage existing and new protected areas, utilising emerging opportunities to finance protected area management with the joint aims of reducing carbon emissions and maximizing biodiversity conservation. Conservation on private lands, through expanding market pressures for sound land management and preventing forest clearance on lands unsuitable for agriculture, is also essential (Soares-Filho et al. 2006).


Text account compilers
Wheatley, H., Hermes, C.

Butchart, S., Ekstrom, J., Khwaja, N., Symes, A. & Taylor, J.

Recommended citation
BirdLife International (2023) Species factsheet: Cranioleuca weskei. Downloaded from on 08/02/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 08/02/2023.