Justification of Red List Category
This species has a very small known range, within which suitable habitat is thought to be severely fragmented. For these reasons it is currently classified as Endangered. However, if further evidence reveals it has a larger range or that habitat fragmentation is not a serious concern then it may warrant downlisting.
Population justification
This species is locally fairly common in suitable habitat (Sharpe and Lentino 2015), and considered less vulnerable than others (such as Grey-headed Warbler Basileuterus griseiceps) to removal of undergrowth for coffee plantations (Boesman in litt. 2006). Its population is estimated to number 2,500-9,999 individuals, equating to 1,667-6,666 mature individuals, which is rounded here to 1,500-7,000 mature individuals.
Trend justification
A moderately rapid and ongoing population decline is suspected on the basis of rates of habitat destruction and fragmentation (Sharpe and Lentino 2008, Sharpe and Lentino 2015), although there are no analyses to support this (J. Pérez-Emán in litt. 2012).
Aglaiocercus berlepschi occupies a restricted range in north-east Venezuela in the Turimiquire Massif (both in the Serranía de Turimiquire to the west of the San Antonio valley and the Cordillera de Caripe to the east) on the borders of Sucre, Anzoategui and Monagas. It was formerly common in parts of its range (Hilty 2003, Sharpe and Lentino 2008) is locally fairly common in places (P. Boesman in litt. 2006, Sharpe and Lentino 2008, C. J. Sharpe in litt. 2011, Sharpe and Lentino 2015). Extent of Occurrence has been estimated at 3,000 km2 (Sharpe and Lentino 2008, Sharpe and Lentino 2015) and 4,200 km2 (BirdLife International).
It lives in humid to wet subtropical montane forest, borders and second growth from 1,450 m to 1,800 m (Hilty 2003, Sharpe and Lentino 2008, Altshuler et al. 2015, Sharpe and Lentino 2015). The species is thought to be less susceptible to removal of undergrowth from forest for coffee growing than other species (P. Boesman in litt. 2006). However, its specific habitat requirements are almost unknown (J. Pérez-Emán in litt. 2012, Altshuler et al. 2015, Sharpe and Lentino 2015).
There has been widespread clearance for agriculture and pasture in the Cordillera de Caripe, resulting in extensive degradation of forest. Clearance, repeated burning and understorey removal for coffee (Boesman and Curson 1995) are the main causes. The slopes of Cerro Negro are largely bare, with the more obvious forest patches actually shade-coffee plantations (Boesman and Curson 1995). There is conversion to coffee, mango, banana and citrus plantations in many parts of the region (Colvee 1999), but extensive forest areas remain (Colvee 1999, Sharpe in litt. 2011). Increases in cash-crop agriculture, especially the cultivation of ocumo blanco (Xanthosoma sagittifolium), since the mid- to late 1980s, have resulted in uncontrolled burning and forest degradation (C. J. Sharpe in litt. 2003). Similar threats are present in the Turimiquire Massif (J. Pérez-Emán in litt. 2012, Sharpe and Lentino 2015). Legally protected areas are not adequately enforced (Sharpe and Lentino 2015). It is considered nationally Endangered in Venezuela (Sharpe 2008, Sharpe and Lentino 2015).
Conservation Actions Underway
Conservation Actions Proposed
Conserve remaining habitat within its restricted range; the establishment of a protected area to safeguard remaining forest within the Serranía de Turimiquire is a high priority (C. J. Sharpe in litt. 2016). Research trends, population size and threats.
Male 22 cm (including outer tail feathers 14-15 cm); female 9.5-11 cm. Male has a short black bill, upperparts shining green with darker glittering green crown; underparts bronzy green with a bright blue gorget; outer tail feathers extremely long and broad, basally deep violet, distally blue. Central tail feathers shorter and blue-green. Female shining green above with blue crown; throat, breast and belly white, green flanks and shorter green, slightly forked tail. Similar spp Very similar to Long-tailed Sylph Aglaiocercus kingi. Subspecies kingi and margarethae have some blue on the crown and green tips to the tail feathers in males, while females are cinnamon below. Ssp caudatus has a blue tail and lacks blue on the throat of males.
Text account compilers
Bird, J., Butchart, S., Sharpe, C J, Symes, A.
Contributors
Boesman, P., Sharpe, C J, Pérez-Emán, J.
Recommended citation
BirdLife International (2023) Species factsheet: Aglaiocercus berlepschi. Downloaded from
http://datazone.birdlife.org/species/factsheet/venezuelan-sylph-aglaiocercus-berlepschi on 08/06/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from
http://datazone.birdlife.org on 08/06/2023.