Data Zone
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 frequently observed across its range (see eBird 2023).
Trend justification
The population trend has not been investigated, but the only threat known to the species is the logging and fragmentation of forests within the range. Tree cover loss within the range is very low (2% over three generations; Global Forest Watch 2023, using Hansen et al. [2013] data and methods disclosed therein). Population declines are therefore likely equally low and localised; they are here tentatively placed in the band 1-9% over three generations.
The species occurs in the highlands of Costa Rica and western Panama.
It inhabits montane forests at 600-2,100 m elevation, including edge habitats and mature secondary forests (Curson et al. 2020).
The only known threat to the species is slow, but ongoing habitat destruction for the expansion of small-scale agriculture and logging (see Curson et al. 2020, Global Forest Watch 2023).
Conservation Actions Underway
No targeted actions are known.
Conservation Actions Proposed
Accurately quantify the population size. Research the species' ecology and exact habitat requirements. Research its tolerance of habitat degradation and conversion. Monitor the population trend. Protect areas of suitable habitat within the range.
Text account compilers
Hermes, C.
Recommended citation
BirdLife International (2024) Species factsheet: Costa Rican Warbler Basileuterus melanotis. Downloaded from
https://datazone.birdlife.org/species/factsheet/costa-rican-warbler-basileuterus-melanotis on 26/12/2024.
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 26/12/2024.