Justification of Red List Category
This recently described species qualifies as Critically Endangered because it is known from a single location and has an extremely small area of occupancy within which habitat quality is continuing to decline owing to conversion for agriculture (particularly coca cultivation).
The species has been described as fairly common (Gallo-Cajiao and López-O. 2014), but given that the area of suitable habitat is thought to be less than 10 km2, the total population size is presumably very small. Based on known densities of the congeneric E. derbyi (20−90 birds per km2 [Cresswell et al. 1999]), it has been estimated at up to 900 individuals (Gallo-Cajiao and López-O. 2014, Fjeldså and Sharpe 2015), which roughly equates to 600 mature individuals, placed here in the band 250-999 mature individuals.
The population is suspected to be decreasing owing to habitat loss and degradation, however the rate of decline has not been quantified.
Eriocnemis isabellae has been recently described from Cauca Department, south-west Colombia, where it occurs in a tiny area of the Serranía del Pinche (Cortés-Diago et al. 2007). Three birds (one male and two females) were mist-netted in 2005 and a total of six further males were caught in 2006 (Cortés-Diago et al. 2007). The global population has not been quantified but is presumably very small, given that the area of suitable habitat is thought to be less than 10 km2, and it is suspected to be decreasing as elfin forest habitat is converted for agriculture and illegal coca plantations.
The species inhabits the cloud and temperate forest zone, within which it appears to be associated with elfin forest on steep slopes along mountain ridges (Cortés-Diago et al. 2007). Elfin forest at the type locality averages 6-8 m in height with frequent natural clearings and is found at around 2,600-2,900 m (Cortés-Diago et al. 2007).
The primary threat is the shifting of the agricultural border towards remaining primary forests, which causes a loss of vegetation cover, contamination of watersheds and soil degradation (Cortés-Diago et al. 2007). Illegal coca cultivation is a major threat due to the lack of governmental presence, with 8.3 % of potentially suitable habitat reportedly damaged annually by coca cultivation. The illegal cultivation of opium poppy (Papaver somniferum) is increasing in the region, and the herbicides used to combat this can pose an additional threat to the species (Cortés-Diago et al. 2007, Gallo-Cajiao and López-O. 2014). The potential completion of a road from El Estrecho in the Patía Valley to Guapi on the Pacific coast would hold serious implications for Serraníadel Pinche (Cortés-Diago et al. 2007).
Conservation Actions Underway
CITES Appendix II. Considered Critically Endangered at the national level in Colombia (Renjifo et al. 2014). There is an ongoing conservation plan involving local authorities, community leaders, the Ministry of Environment, The Hummingbird Conservancy, Ecohabitats Foundation and local residents. Serranía del Pinche has been legally designated as the 7256 ha Serranía del Pinche Protective Forest Reserve (Gallo-Cajiao and López-O. 2014).
Conservation Actions Proposed
Carry out further studies to determine status and population size. Develop a Species Action Plan. Continue and extend local conservation and education initiatives. Work towards the creation of a protected area in the Serranía del Pinche.
The male is blackish-green, with iridescent blue-green rump and blue-black tail, bluish-violet undertail, and white leg puffs, and differs from other Eriocnemis in having a bicoloured blue-violet and green gorget. Females are similar to E. nigrivestis and E. vestitus but underparts are more intensively fringed rufous with turquoise reflections on the belly centre (Cortés-Diago et al. 2007).
Text account compilers
Wheatley, H., Sharpe, C.J., Symes, A., Ashpole, J
Salaman, P., Cortés, O.
BirdLife International (2023) Species factsheet: Eriocnemis isabellae. Downloaded from http://www.birdlife.org on 31/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 31/03/2023.