Black-thighed Puffleg Eriocnemis derbyi


Justification of Red List category
This species has a very large range, and hence does not 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 trend appears to be stable, and hence the species does not 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 global population size has not been quantified, but this species is described as uncommon to locally common (Heynen and Boesman 2020). It is frequently recorded (eBird 2022).

Trend justification
The population trend has not been investigated. Tree cover within the range is lost at a rate of <2% over ten years (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). While the species shows a preference for forest borders, it readily tolerates open and disturbed habitats (Heynen and Boesman 2020); consequently, the current rate of tree cover loss may not be affecting the population. Therefore, in the absence of evidence for any declines or substantial threats, the population is suspected to be stable.

Distribution and population

Eriocnemis derbyi occurs in the Central Andes of Colombia from Antioquia south to Pichincha in northern Ecuador.


It occurs in humid forest edge, second growth, bushy partially open pastures and ravines at 2,500-3,600 m, but usually above 2,900 m (Hilty and Brown 1986, Fjeldså and Krabbe 1990). It readily accepts man-made habitats like pastures and gardens, and is seldom found in forest interior (Heynen and Boesman 2020). However, although tolerant of habitat degradation, it apparently prefers borders of montane forest and low scrub at the timberline.


While there is slow habitat loss and degradation ongoing within the range, the species readily accepts man-made, open and degraded habitats and as such is currently not thought to be at risk.

Conservation actions

Conservation Actions Underway
CITES Appendix II. It occurs in several protected areas throughout its range, including Los Nevados and Puracé National Parks, Colombia. It is listed as Vulnerable at the national level in Ecuador (Freile et al. 2019).

Conservation Actions Proposed
Search for the species in new areas of potentially suitable habitat. Accurately quantify the population size. Monitor population trends.


Text account compilers
Hermes, C.

Benstead, P., Capper, D., Sharpe, C.J. & Symes, A.

Recommended citation
BirdLife International (2024) Species factsheet: Eriocnemis derbyi. Downloaded from on 21/02/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from on 21/02/2024.