Esmeraldas Woodstar Chaetocercus berlepschi


Justification of Red List Category
This species has a very small and severely fragmented range. There are also on-going and very rapid declines in its range, and presumably population. It is therefore listed as Endangered.

Population justification
The population is estimated to number 250-999 mature 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 375-1,499 individuals in total, rounded here to 350-1,500 individuals.

Trend justification
A very rapid and ongoing population decline is suspected on the basis of continued habitat destruction and fragmentation. The reduction has been estimated to be greater than 50% over a ten year period (Harris et al. 2009).

Distribution and population

Chaetocercus berlepschi is restricted to a small area of west Ecuador (Esmeraldas, Manabí, Santa Elena and Guayas), where it is very rare and localised (fewer than 15 known sites). Very little suitable habitat remains, and the species's distribution is extremely fragmented. Small numbers persist south of the río Ayampe, Machalilla National Park (Becker et al. 2000), Guayas, between October and March, but it is apparently absent during other months. In 1993, it was found near Súa, Esmeraldas, in an area severely threatened by logging (Best et al. 1996), and, in 1998, one male was recorded on Isla de la Plata (Becker et al. 2000). Several males were observed in the Loma Alta Communal Reserve, Guayas, in December 2002 and 2003, and a male was at Dos Mangas Communal Reserve, Guayas in December 2005 (Agreda 2007). During 2007-2008, 11 new localities were found in the lowlands of Manabí and Santa Elena (Harris et al. 2009).


This hummingbird inhabits semi-deciduous to evergreen moist (c.1,500 mm annual rainfall) forest along the Pacific coast of western Ecuador from around sea level to 750 m elevation (Becker et al. 2000, Ridgely and Greenfield 2001, Agreda 2007, Harris et al. 2009). The vast majority of records come from the rainy season, i.e. from mid-October until late May. The species is found along a gradient from low elevation (0-250 m), partially disturbed areas (Becker et al. 2000, Ridgely and Greenfield 2001) to more intact, higher elevation (250-750 m), misty garúa (low-level cloud) forest in the hills of the Cordillera Chongón-Colonche (Agreda 2007). A recent record from a garden (J. Croxall in litt. 2011) shows at least a partial tolerance for degraded habitat. It appears to breed in lower elevation, disturbed areas along the central Ecuadorian coast and move to northwestern Ecuador for the non-breeding season (Harris et al. 2009). A male studied in 2005 fed mainly in a flowering patch of understorey herb Razisea (Agreda 2007). Other common foodplants include Kohleria spicata, Cornutia pyramidae and flowering Vitex gigantea trees (Harris et al. 2009, E. von Horstman in litt. 2012). A total of 21 active nests were encountered between October and April, at 30-350 m elevation and within 14 km of the sea (Harris et al. 2009, Juiña et al. 2010). Most were in areas disturbed by cattle ranching, but adjacent to large blocks of forest (Harris et al. 2009, Juiña et al. 2010). Nesting biology is discussed further by Juiña et al. (2010).


All forest-types within its range have greatly diminished owing to logging and agricultural clearance (Dodson and Gentry 1991, Best et al. 1996). Persistent grazing by goats and cattle damages the understorey, prevents regeneration and is a serious current threat (Dodson and Gentry 1991, Pople et al. 1997). Rapid habitat loss continues, at least in unprotected areas, and will soon remove almost all extant forest (Dodson and Gentry 1991). Uncontrolled forest fires are a major threat to forest in the Cordillera Chongón-Colonche (E. von Horstman in litt. 2000, 2008). Even in Machalilla, its habitat is threatened by illegal settlement, deforestation, livestock-grazing and habitat clearance by people with land rights (Becker et al. 2000, Harris et al. 2009)..

Conservation actions

Conservation Actions Underway
CITES Appendix II. It occurs in Machalilla National Park, but this provides inadequate protection (Harris et al. 2009). The 7.5 km2 Loma Alta Ecological Reserve receives local community support as a watershed reserve and conservation area (Becker and López Lanús 1997). The Chongón-Colonche Protection Forest may support the species, and a biological corridor linking forest remnants between this site and the Cerro Blanco Protected Forest is being set up (E. von Horstman in litt. 2012).

Conservation Actions Proposed
Survey remnant moist forest in the Colonche Hills. Determine its status on Isla de la Plata. Exclude roaming livestock from Machalilla (Best et al. 1996, Becker and López Lanús 1997). Prevent further loss and degradation of habitat within Machalilla. Map and protect forest within the Cordillera Chongón-Colonche (Becker and López Lanús 1997, E. von Horstman in litt. 2000, 2008). Encourage ecotourism at Loma Alta Ecological Reserve to financially benefit local people (Becker and López Lanús 1997). Establish a new protected area within the breeding habitat of the species (Harris et al. 2009).


6-7 cm. Tiny hummingbird with striking violet, green and white plumage in male. Coppery-green upperparts, flanks and narrow breast-band in male, which also has iridescent rosy-violet gorget, short white postocular, greyish-white breast and forked tail, with outermost feathers reduced to shafts. Female has coppery-green upperparts with a white post-ocular stripe, and peach-suffused whitish underparts, with buff-tinged throat, and tawny tail with green central rectrices and a black subterminal bar. Both sexes have a straight black bill. Similar spp. Underparts pattern of both sexes differs from all other woodstars in range, as does tail pattern of female. Voice a series of rapid chit-cheet and chit-chit-cheet calls


Text account compilers
Benstead, P., Isherwood, I., Pilgrim, J., Sharpe, C J, Stuart, T., Symes, A. & Khwaja, N.

Horstman, E. & Croxall, J.

Recommended citation
BirdLife International (2019) Species factsheet: Chaetocercus berlepschi. Downloaded from http://www.birdlife.org on 19/04/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 19/04/2019.