Data Zone
Justification of Red List category
This species is listed as Vulnerable because it is restricted to a small range. Habitat within the range is degraded and lost due to agricultural expansion.
Population justification
The population size has not been quantified directly, but the species is described as uncommon to locally fairly common (B. P. Walker in litt. 1995; J. Hornbuckle in litt. 1999; Begazo et al. 2001; Lloyd 2020). The population is tentatively suspected to number 1,000-2,499 individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated extent of occurrence is likely to be occupied. This estimate is equivalent to 667-1,666 mature individuals, rounded here to 600-1,700 mature individuals.
The subpopulation structure has not been investigated. Based on observational records (per eBird 2020), the species is tentatively assumed to form five subpopulations, the largest of which may number less than 250 mature individuals.
Trend justification
A slow and ongoing population decline is suspected, owing to the degradation and loss of montane scrub habitat for agricultural expansion and firewood collection. The rate of decline is likely low; it is here tentatively placed in the band 1-9% over ten years.
Synallaxis zimmeri has a small range on the Pacific slope of the Andes in west-central Peru. There are records from south Cajamarca, La Libertad and Ancash, with the largest population in the Cordillera Negra (SERFOR 2018).
The species is restricted to scrub and dense, tangled undergrowth with scattered small trees, at elevations of 1,800-2,900 m. Its preferred habitat is naturally patchily distributed (Lloyd 2020). It is usually encountered in pairs or family groups, foraging for insects in moss clumps and along vines and branches (Lloyd 2020). Juveniles and active nests have been observed in May (Franke and Salinas 2000; Lloyd 2020).
Dense undergrowth habitat within its range is severely degraded by grazing of cattle and goats (Remsen 2003; Lloyd 2020), and is cleared for agricultural expansion and plantations. Locally, montane scrubs are cut for firewood collection (Begazo et al. 2001; Lloyd 2020).
Conservation Actions Underway
No targeted actions are known.
16.5 cm. Pale spinetail with black tail. Drab grey head and nape with darker auriculars, and pale lores and throat. Interrupted white eye-ring. Olivaceous-grey upperparts. Dusky wings, broadly edged rufous-brown. Rufous wing-coverts and rump. Black tail with conspicuous rufous on outer rectrices. Rufous-cinnamon breast becoming richer rusty towards belly. Dark bill, iris and legs. Voice Song consists of two identical, snarling notes quick-quick lasting about one second, repeated every 1-2 seconds, faster when excited.
Text account compilers
Hermes, C.
Contributors
Hornbuckle, J., Isherwood, I., Pople, R., Sharpe, C.J., Stuart, T., Symes, A. & Walker, B.P.
Recommended citation
BirdLife International (2024) Species factsheet: Russet-bellied Spinetail Synallaxis zimmeri. Downloaded from
https://datazone.birdlife.org/species/factsheet/russet-bellied-spinetail-synallaxis-zimmeri 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.