||Cyanolyca nanus (Du Bus De Gisignies, 1847)
Cyanolyca nana (Du Bus De Gisignies, 1847) [orth. error]
||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
||20-23 cm. Small, slender and agile, blue jay. Slate-blue except for black mask bordered by slight, whitish supercilium and whitish throat highlighted by diffuse breast-band. Voice Repeated two-syllable, high-pitched nasal yeeyip yeeyip. Occasionally also longer, harsh squawk. Hints Often accompanies mixed-species flocks with Grey-barred Wren Campylorhynchus megalopterus.
|Red List Category & Criteria:
||Butchart, S. & Symes, A.
||Escalante, P., Navarro, A. & Peterson, A.
||Capper, D., Harding, M., Isherwood, I., Mahood, S., Pople, R., Sharpe, C.J.
This species is considered Vulnerable because it has a small range, which is declining rapidly in response to habitat loss.
|Previously published Red List assessments:|
- 2012 – Vulnerable (VU)
- 2008 – Vulnerable (VU)
- 2005 – Vulnerable (VU)
- 2004 – Vulnerable (VU)
- 2000 – Vulnerable (VU)
- 1996 – Endangered (EN)
- 1994 – Endangered (EN)
- 1988 – Threatened (T)
|Range Description:||This species is known historically from Veracruz adjacent to the border with Puebla and the Sierras Juárez, Aloapaneca and Zempoaltepec in Oaxaca south-east Mexico. It was feared extinct throughout this range except for the Cerro San Felipe in the Sierra Aloapaneca, where it remains quite common. However, it is now known to be more widespread. There are records from Tangojó in extreme east Querétaro, north Hidalgo, central Veracruz and La Chinantla in north Oaxaca, and it may be locally common where suitable habitat persists (M. Angel Martínez, E. Ruelas and R. Sanchez pers. comm. to A. G. Navarro in litt. 1998, A. G. Navarro in litt. 1998, Rojas-Soto et al. in press). |
|♦ Continuing decline in area of occupancy (AOO):||Yes|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||44800|
|♦ Continuing decline in extent of occurrence (EOO):||Yes||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||6-10||♦ Continuing decline in number of locations:||Yes|
|♦ Extreme fluctuations in the number of locations:||No||♦ Lower elevation limit (metres):||1400|
|♦ Upper elevation limit (metres):||3200|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The population size is preliminarily estimated to fall into the band 10,000-19,999 individuals. This equates to 6,667-13,333 mature individuals, rounded here to 6,000-15,000 mature individuals.|
Trend Justification: No quantitative data are available for the calculation of population trends; however, the species is suspected to be declining rapidly in line with habitat degradation within its range.
|Current Population Trend:||Decreasing|
|♦ Number of mature individuals:||6000-15000||♦ Continuing decline of mature individuals:||Yes|
|♦ Extreme fluctuations:||No||♦ Population severely fragmented:||No|
|♦ No. of subpopulations:||2-100||♦ Continuing decline in subpopulations:||Yes|
|♦ Extreme fluctuations in subpopulations:||No||♦ All individuals in one subpopulation:||No|