Oaxaca Hummingbird Eupherusa cyanophrys


Justification of Red List Category
Habitat is probably contiguous between the two areas from which this species is known. The lack of records in these intervening areas is almost certainly indicative of the paucity of field studies. Even including these areas of presumed occurrence, the species is suspected to have a very small population size, which is likely declining as a result of habitat loss. Consequently it qualifies as Endangered.

Population justification
The population is estimated 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.

Trend justification
The species's population is suspected to be declining in line with the ongoing clearance of montane forest within its range. However, deforestation analysis by Tracewski et al. (2016) showed an annual decline in forest cover within this species’s range to be c.0.1% between 2000 and 2012, which would roughly equate to a decline of 1.1% over three generations (c.12.5 years).

Distribution and population

Eupherusa cyanophrys is endemic to the Sierra Miahuatlán, an isolated mountain range in southernmost Oaxaca, Mexico. It has been found in two areas of the sierra, separated by c.60-70 km: in the west along the Puerto Escondido road; and to the east along the Puerto Angel road at its intersection with the río Jalatengo. Appropriate habitat appears widespread along the latter road (Roberson and Carratello 1997), and it was locally common until at least 1997 (S. N. G. Howell in litt. 1998, A. G. Navarro in litt. 1998), but its known range remains highly restricted. Tracewski et al. (2016) estimated the maximum Area of Occupancy (calculated as the remaining tree area within the species’s range) to be c.2,070 km2.


It is primarily restricted to cloud-forest and the upper reaches of tropical semi-deciduous forest at 1,300-1,950 m, occasionally wandering (possibly seasonally) to c.700 m on adjacent mountain slopes. It also occurs up to 2,500 m, but at lower densities (Howell and Webb 1995). Nesting has been recorded in September-November and May (Howell and Webb 1995).


The cloud-forests on the Sierra Miahuatlán were essentially unspoilt by human activity until the mid-1960s, when huge areas were cut and burnt for the planting of maize. Lower montane forest in the sierra is still being cleared, largely for the cultivation of citrus fruits (Dinerstein et al. 1995). In October 1997, Hurricane Paulina destroyed large portions of suitable cloud-forest habitat (A. G. Navarro in litt. 1998), but the full impact of this stochastic event on the species is unknown.

Conservation actions

Conservation Actions Underway
CITES Appendix II. This species is on the watch list as part of the State of North America's Birds (North American Bird Conservation Initiative 2016).

Conservation Actions Proposed
Conduct surveys to assess the precise distribution and the extent of altitudinal migration. Carry out surveys to obtain a population estimate and determine the impact of Hurricane Paulina. Designate a protected area in the Sierra de Miahuatlán encompassing the range of this species (Hernández-Baños et al. 1995).


11 cm. Distinctive, mainly green hummingbird. Rufous secondaries and white outer rectrices. Male glittering green below with turquoise-blue crown and white undertail. Female green crown, white postocular spot and grey ear-coverts. Grey underparts, less rufous secondaries and dusky green edges to outer rectrices. Immature is similar to female. Similar spp. Berylline Hummingbird Amazilia beryllina has rufous tail, lacks blue crown and has red lower mandible. Voice Buzzy, chipping notes. Jerky, warbling song.


Text account compilers
Isherwood, I., Benstead, P., Sharpe, C.J., Taylor, J., Westrip, J., Capper, D.

Navarro, A., Howell, S.

Recommended citation
BirdLife International (2022) Species factsheet: Eupherusa cyanophrys. Downloaded from http://www.birdlife.org on 26/09/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 26/09/2022.