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VU
Mexican Woodnymph Thalurania ridgwayi

Justification
The combination of a small and fragmented range, plus continuing habitat loss, qualify this species as Vulnerable. However, knowledge is poor and new information may result in a reclassification to a higher or lower threat category.

Taxonomic source(s)
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

Taxonomic note
Thalurania colombica (del Hoyo and Collar 2014) was previously split as T. colombica and T. fannyi following Sibley and Monroe (1990, 1993), and subsequently T. ridgwayi was recognised following AOU (1998).

Identification
10 cm. Medium-sized, mainly green hummingbird with black wings. Male has iridescent blue forehead and bluish-green hindcrown, iridescent emerald throat and slightly forked, bluish-black tail. Female green above with small, white postocular spot, greyish below with green discs on flanks. Bluish-black tail with white tips to outer rectrices and green central rectrices. Straight black bill. Immature unknown. Similar spp. Male Broad-billed Hummingbird Cynanthus latirostris has red bill, blue throat and lacks blue crown, female has dusky red bill and noticeable white postocular stripe. Berylline Hummingbird Amazilia beryllina is pale below with rufous tail and wing-patch. Voice Fluid rattling notes and trills.

Distribution and population
Thalurania ridgwayi is patchily distributed in south Nayarit, Jalisco and Colima states, west Mexico, where it is uncommon to locally common. Surveys in central and south Mexico have failed to find the species and its restricted range seems real rather than the result of incomplete knowledge.

Population justification
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
The species's population is suspected to be declining slowly, in line with the on-going clearance of forest within its range for agriculture.

Ecology
It occurs in humid, semi-deciduous woodland and shade coffee plantations at elevations of 250-1,200 m. Its ecology is poorly known, but it is often found along streams and generally avoids edge habitats (Howell and Webb 1995a).

Threats
The reasons for its patchy distribution, and its precise ecological requirements are poorly understood. The avoidance of edge habitats indicates that it is probably threatened by habitat destruction, particularly for the cultivation of sun coffee.

Conservation Actions Underway
CITES Appendix II. There are records from three protected areas: Cerro San Juan Special Biosphere Reserve, Nayarit; Sierra de Manantlán Biosphere Reserve, Jalisco/Colima; and Nevados de Colima National Park, Jalisco/Colima (Wege and Long 1995).Conservation Actions Proposed
Conduct surveys to determine the species's precise distribution and obtain an estimate of its population size. Investigate its ecological requirements. Assess the severity of the threat from habitat destruction. Increase the area of suitable habitat that has protected status.

References
Collar, N. J.; Gonzaga, L. P.; Krabbe, N.; Madroño Nieto, A.; Naranjo, L. G.; Parker, T. A.; Wege, D. C. 1992. Threatened birds of the Americas: the ICBP/IUCN Red Data Book. International Council for Bird Preservation, Cambridge, U.K.

Howell, S. N. G.; Webb, S. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press, Oxford.

Wege, D. C.; Long, A. J. 1995. Key Areas for threatened birds in the Neotropics. BirdLife International, Cambridge, U.K.

Further web sources of information
Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note taxonomic treatment and IUCN Red List category may have changed since publication.

Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note, taxonomic treatment and IUCN Red List category may have changed since publication.

Explore HBW Alive for further information on this species

Recuento detallado de la especie tomado del libro Aves Amenazadas de las Americas, Libro Rojo de BirdLife International (BirdLife International 1992). Nota: la taxonomoía y la categoría de la Lista Roja de la UICN pudo haber cambiado desde esta publicación.

Search for photos and videos, and hear sounds of this species from the Internet Bird Collection

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

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2014) Species factsheet: Thalurania ridgwayi. Downloaded from http://www.birdlife.org on 22/08/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/08/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Key facts
Current IUCN Red List category Vulnerable
Family Trochilidae (Hummingbirds)
Species name author Nelson, 1900
Population size 6000-15000 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 14,500 km2
Country endemic? Yes
Links to further information
- Additional Information on this species