Family Thrushes (Turdidae)

Least Concern

Western Bluebird (Sialia mexicana)


French: Merlebleu de l’Ouest German: Blaukehl-Hüttensänger Spanish: Azulejo occidental

Sialia Mexicana


, 1832,

tableland of Mexico


Sister to S. sialis#R. Geographical variation relatively slight, but individual variation rather wide; races jacoti and nelsoni possibly untenable. Proposed Mexican races anabelae (N Baja California) and australis (S Mexican Plateau) considered indistinguishable from, respectively, occidentalis and nominate. Six subspecies recognized.

Subspecies and Distribution
  • S. m. occidentalis J. K. Townsend, 1837 – SW Canada S to NW Mexico (N Baja California); N populations migratory.
  • S. m. bairdi Ridgway, 1894 – interior W USA S to NW Mexico (S Sonora and NW Chihuahua).
  • S. m. jacoti A. R. Phillips, 1991 – S USA (Davis Mts, in S Texas) and NE Mexico (San Luis Mts).
  • S. m. amabilis R. T. Moore, 1939 – NW Mexico (SE Chihuahua to NW Zacatecas).
  • S. m. nelsoni A. R. Phillips, 1991 – NE & C Mexico (N Coahuila to W San Luis Potosí, N Guanajuato and NE Jalisco).
  • S. m. mexicana Swainson, 1832 – C Mexico (Veracruz to N Puebla and Hidalgo, W to Michoacán and Aguascalientes).
  • Descriptive notes

    16·5–19 cm; 24–31 g. Male nominate race has entire head to uppermost breast, and upperparts, rich blue, patch on scapulars rusty-red, blackish tips of tail... read more


    Two songs distinguished, but appear to intergrade. Dawn/pre-dawn song includes common “few... read more


    Hilly and montane regions with open park-like coniferous and deciduous forest, ragged forest... read more

    Food and feeding

    Mainly arthropods in spring and summer; mainly small fruits and some seeds in autumn and winter. Major animal items include grasshoppers (... read more


    Mid-Apr to early Aug; normally 1–2 broods per year, depending on local conditions, but up to three in Oregon. Monogamous, pair-bond... read more


    Partial and/or altitudinal migrant; winters usually in small flocks, often family parties,... read more

    Status and conservation

    Not globally threatened. Widespread and relatively numerous; fairly common to common in Mexico. Densities vary with habitat, but in optimal conditions (e.g. ponderosa pine... read more

    Recommended citation

    Collar, N. & Christie, D.A. (2020). Western Bluebird (Sialia mexicana). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 23 January 2020).