Maranon Crescentchest Melanopareia maranonica


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). The population size may be small, 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). 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). For these reasons the species is evaluated as Least Concern.

Population justification
The population size of this species has not been quantified, but the speces is described as local and uncommon. Tentatively, the population is suspected to number 2,500-9,999 mature individuals, but this requires confirmation.
The subpopulation structure has not been investigated, but based on continuous observational records within the range (per eBird 2020), it is assumed that all individuals belong to the same subpopulation.

Trend justification
Data on population trends are lacking, but declines are suspected owing to habitat loss. Tree cover within the range has been lost at a rate of 3% over the last ten years (Global Forest Watch 2020), but even though the species is able to tolerate some habitat disturbance the rate of population decline may be higher due to the additional impacts of degradation of forests and arid scrub. Tentatively, the rate of decline is here placed in the band 1-9% over ten years.

Distribution and population

Melanopareia maranonica occurs in north-west Peru (local in the upper río Marañón valley of Cajamarca and in Amazonas) and extreme south Ecuador (Zumba region of south Zamora-Chinchipe) (Ridgely and Tudor 1994; Chávez et al. 2021).


The species is uncommon and local in dry deciduous forest, arid lowland scrub and riparian thickets at 200-800 m, where it apparently tolerates low levels of disturbance (Ridgely and Tudor 1994; Parker et al. 1996; Stattersfield et al. 1998; R. Webster and R. A. Rowlett in litt. 1998).


Its habitat in the Marañón drainage has progressively deteriorated during a prolonged period of cultivation (Ridgely and Tudor 1994), while the spread of oil palm plantations, cattle-ranching and logging are all serious threats within its small range (Dinerstein et al. 1995). Large parts of the range overlap with mining and hydrocarbon concessions (Bax et al. 2019), which contributes to further habitat degradation. Oil extraction is a potential future problem (Dinerstein et al. 1995).

Conservation actions

Conservation Actions Underway
No targeted actions are known.

Conservation Actions Proposed
Quantify the population size. Monitor known sites to determine rates of population change. Monitor rates of habitat loss. Conduct ecological studies to determine whether the species can genuinely tolerate secondary or disturbed habitats. As a precaution, protect significant areas of suitable habitat.


Text account compilers
Hermes, C.

Angulo Pratolongo, F., Capper, D., Gilroy, J., O'Brien, A., Rowlett, R.A., Sharpe, C.J. & Webster, R.

Recommended citation
BirdLife International (2023) Species factsheet: Melanopareia maranonica. Downloaded from on 22/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 22/03/2023.