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 under 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 size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (under 10,000 mature individuals with a continuing decline estimated to be over 10% in ten years or three generations, or with a specified population structure). 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 (over 30% decline over ten years or three generations). 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' (Stotz et al. 1996). This species is considered to have a medium dependency on forest habitat, and tree cover is estimated to have declined by 2.5% within its mapped range over the past 10 years (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). Therefore, as a precautionary measure, it is tentatively suspected that this loss of cover may have led to a decline of between 1-19% in the species' population size over the same time frame.
Trend justification
.
This species has a restricted distribution in south-west Ecuador and north-west Peru, occurring in El Oro and Loja provinces, Ecuador, and Tumbes, Piura and northern Lambayeque departments, Peru (Sibley and Monroe 1990). The species occurs in the North-west Peru Biosphere Reserve where it is uncommon to rare (Parker et al. 1995), and in the small El Tundo Nature Reserve in Loja province, Ecuador, where it is fairly common (I. Isherwood and J. Willis verbally 1998).
The species is found mainly in scrub, secondary woodland and forest borders in both arid and semi-humid regions (Ridgely and Tudor 1994), and has been recorded from thickets of Chusquea bamboo (I. Isherwood and J. Willis verbally 1998). Most records come from between 500 and 1,500 m altitude, but birds have been seen as high as 2,300 m in Ecuador (Ridgely and Tudor 1994). It often joins mixed species flocks, foraging mainly in relatively dense vegetation not far above ground level (Parker et al. 1995, I. Isherwood and J. Willis verbally 1998). Breeding probably takes place during the wet season (Brown 1941).
Much of the land within the species's rather restricted altitudinal range has been cleared for agriculture, and destruction of habitat is ongoing (I. Isherwood and J. Willis verbally 1998).
Text account compilers
Rutherford, C.A.
Recommended citation
BirdLife International (2024) Species factsheet: Chapman's Antshrike Thamnophilus zarumae. Downloaded from
https://datazone.birdlife.org/species/factsheet/chapmans-antshrike-thamnophilus-zarumae on 23/12/2024.
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 23/12/2024.