Chiguanco Thrush Turdus chiguanco Scientific name definitions

The Chiguanco Thrush is a sturdy member of the widespread genus Turdus. Two main forms exist, with males of the southern race appearing blackish with an obvious orange eyering, while northern males are paler brown without an obvious eyering. Chiguanco Thrush overlaps in range with Great Thrush and can be visually confused with this larger congener. The Chiguanco Thrush can be found hopping on the ground in arid and agricultural areas. The nesting biology of the southern race is fairly well documented, while that of the northern races is largely undocumented.

Chiguanco Thrush (chiguanco/conradi)

25–30 cm (1 Clement, P. and Hathway, R. (2000). Thrushes. Christopher Helm & A&C Black, London. Close ); 75–120 g (2 Fiora, A. (1934) El peso de las aves. Hornero 5: 358–365. Close , 3 Salvador, S. A. (1988). Datos de peso de aves argentinas. El Hornero 13:78–83. Close , 4 Salvador, S. A., and A. G. Di Giacomo (2014). Datos de pesos de aves argentinas. Parte 3. Historia Natural 4(2):63–88. Close ). Nominate race is plain olive grey-brown, slightly paler below, with vague buffy throat streaks; bill and legs yellow; iris red to chestnut. Sexes similar.

Juvenile is olive grey-brown above, with buff flecking on crown and wing-coverts, buffy supercilium and underparts with brown mottling (5 Collar, N. J. (2005). Chiguanco Thrush (Turdus chiguanco). In Handbook of the birds of the World, Volume 10: Cuckoo-shrikes to thrushes (del Hoyo, J., A. Elliott and D. A. Christie), Lynx Edicions, Barcelona, Spain. pp. 675. Close ). From Clement and Hathaway (1 Clement, P. and Hathway, R. (2000). Thrushes. Christopher Helm & A&C Black, London. Close ) (ssp. not indicated): "Juvenile dull greyish-olive tinged brown above with pale buff central shaft-streaks to mantle; wings and tail browner than adult, with pale grey or buffish grey edges to primaries; median and greater coverts tipped with small pale or whitish-buff spots. forehead to over eyes also with small whitish spots. Chin and throat pale buff mottled with brown spots or bars at tips; breast more boldly marked with pale buff centres and broad pale brown tips, form ing a spotted pattern and becoming more barred with broad dark brown tips on lower breast, belly and flanks. Undertail-coverts buff-brown with broad pale buff central shaft-streaks. Bill, legs and feet dull yellow."

Iris and Orbital Skin

iris red to chestnut, orbital skin yellow (anthracinus) or dark (conradi, chiguanco)

Bill

yelllow

Tarsi and Toes

yellow to yellow-orange

Race conradi often subsumed into nominate, (Ridgely & Tudor 1989). Race anthracinus sometimes separated into its own species, largely due to its darker gray-brown plumage, narrow but distinct yellow eyering vs none, lack of any streaking on chin and upper throat in males, shorter wing, song of 4–7 vs 2–3 melodious notes followed by one or a few higher-pitched squeaky ones (thus with more whistled notes) which are shorter and given at higher pace (6 Boesman, P. (2016). Notes on the vocalizations of Chiguanco Thrush (Turdus chiguanco). HBW Alive Ornithological Note 307. In: Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. Close , 7 del Hoyo, J., N. J. Collar and G. M. Kirwan (2019). Sombre Thrush (Turdus anthracinus). In Handbook of the Birds of the World Alive (del Hoyo, J., A. Elliott, J. Sargatal, D. A. Christie and E. de Juana), Lynx Edicions, Barcelona, Spain. Available at https://www.hbw.com/node/1344025. Close ). Relationship to much larger T. fuscater worthy of study (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close ).

Central Ecuador southward to southern costal Peru, central and western Bolivia, northern Chile (Antofagasta, Atacama), and west-central Argentina (locally in adjacent C Chile) (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close , 11 Hennessey, A. B., S. K. Herzog, and F. Sagot (2003). Lista Anotada de las Aves de Bolivia. Fifth edition. Asociación Armonía/BirdLife International, Santa Cruz de la Sierra, Bolivia. Close , 12 Jaramillo, A., P. Burke, D. Beadle, and J. Donoyan (2005). Aves de Chile: incluye la península Antártica, las islas Malvinas y Georgia del Sur. Lynx Ediciones, Barcelona, Spain. Close , 13 Ridgely, R. S., and G. Tudor (2009). Field Guide to the Songbirds of South America: the Passerines. University of Texas Press, Austin, Texas, USA. Close , 14 Schulenberg, T. S., D. F. Stotz, D. F. Lane, J. P. O’Neill, and T. A. Parker (2010). Birds of Peru. Revised and updated edition. Princeton University Press, Princeton, NJ, USA. Close , 15 Freile, J., and R. Restall (2018). Birds of Ecuador. Bloomsbury, London, UK. Close ).

Agricultural and semi-open areas with scattered trees, thickets and hedges, gardens, parks and light scrubby deciduous woodland with cacti, mainly in arid regions but usually near watercourses or in irrigated areas and around human dwellings (16 Wetmore, A. (1926). Observations on the birds of Argentina, Paraguay, Uruguay and Chile. United States National Museum Bulletin 133:1–448. Close , 17 Partridge, W. H. (1953). Observaciones sobre aves de las provincias de Córdoba y San Luis. Hornero 10:23–73. Close ). Also in bushy gorges in puna zone, Polylepis woodland (where highest densities achieved in medium-sized patches) and montane scrub (18 Herzog, S.K., Soria A., R. and Matthysen, E. (2003). Seasonal variation in avian community composition in a high-Andean Polylepis (Rosaceae) forest fragment. Wilson Bull. 115(4): 438–445. Close , 19 Lloyd, H. (2008). Abundance and patterns of rarity of Polylepis birds in the Cordillera Vilcanota, southern Perú: implications for habitat management strategies. Bird Conservation International. 18(2): 164–180. Close , 20 Bellis, L. M., A. M. Pidgeon, C. Alcántara, S. Dardanelli and V. C. Radeloff (2015). Influences of succession and erosion on bird communities in a South American highland wooded landscape. Forest Ecology and Management 349:85–93. Close ). Prefers more arid environments than T. fuscater, but they can overlap in Polylepis woodland and at forest edge. Will colonize roads through humid montane forest (21 Dorst, J. (1956). Recherches ecologiques sur les oiseaux des hauts plateaux peruviens. Travaux de L'Institut Francais d'Etudes Andines 5:83–140. Close , 22 Dorst, J. (1961). Étude d'une collection d'oiseaux rapportée des hauts plateaux Andins du Pérou méridional. Bulletin du Muséum National d'Histoire Naturelle 33(2): 563–570. Close , 23 Koepcke, M. (1954). Corte ecológico transversal en los Andes del Perú central con especial consideración de las aves. Part 1. Costa, vertientes occidentales y región altoandina. Mem. Mus. Hist. Nat. Javier Prado 3: 1–119. Close , 24 Koepcke, M. (1958) Die Vögel des Waldes von Zárate (Westhang der Anden in Mittelperu). Bonner zoologische Beiträge 9: 130–193. Close ). Mostly 1600–4000 m, sometimes to 4300 m (Peru) and exceptionally 4650 m (Bolivia), but only to 3200 m in Ecuador and reaching lower, almost to sea-level, in Peru and N Chile. Mostly 700–3500 m, occasionally to 550 m in Bolivia (mainly austral winter/spring) (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close , 25 Ridgely, R. S. and P. J. Greenfield. (2001). The birds of Ecuador. Ithaca, NY: Cornell University Press. Close , 11 Hennessey, A. B., S. K. Herzog, and F. Sagot (2003). Lista Anotada de las Aves de Bolivia. Fifth edition. Asociación Armonía/BirdLife International, Santa Cruz de la Sierra, Bolivia. Close , 12 Jaramillo, A., P. Burke, D. Beadle, and J. Donoyan (2005). Aves de Chile: incluye la península Antártica, las islas Malvinas y Georgia del Sur. Lynx Ediciones, Barcelona, Spain. Close , 13 Ridgely, R. S., and G. Tudor (2009). Field Guide to the Songbirds of South America: the Passerines. University of Texas Press, Austin, Texas, USA. Close , 14 Schulenberg, T. S., D. F. Stotz, D. F. Lane, J. P. O’Neill, and T. A. Parker (2010). Birds of Peru. Revised and updated edition. Princeton University Press, Princeton, NJ, USA. Close ).

Presumably sedentary in northern portion of its range. In Ecuador (conradi) has been known to wander as far north as Volcán Pichincha (26 Krabbe, N. (1992). Notes on distribution and natural history of some poorly known Ecuadorean birds. Bulletin of the British Ornithologists’ Club 112(3):169–174. Close ), but these records may represent a gradual expansion of their range in response to habitat degregation. In southern populations (nominate chiguanco) strong seasonal fluctuations in abundance have been documented, in high-altitude Polylepis forest in Bolivia, that are strongly indicative of seasonal wandering (and elevational movements) in response to food availability (18 Herzog, S.K., Soria A., R. and Matthysen, E. (2003). Seasonal variation in avian community composition in a high-Andean Polylepis (Rosaceae) forest fragment. Wilson Bull. 115(4): 438–445. Close ). In Chile occasionally recorded during austral winter south as far as Maule and foothills around Santiago (27 Goodall, J. D., A. W. Johnson, and R. A. Philipps (1946). Las aves de Chile. Volume 1. Platt Establecimientos Gráficos, Buenos Aires. Close ).

Usually observed alone or in loose pairs. Forages on ground in short grass in semi-open country (21 Dorst, J. (1956). Recherches ecologiques sur les oiseaux des hauts plateaux peruviens. Travaux de L'Institut Francais d'Etudes Andines 5:83–140. Close , 28 Walker, B., and J. Fjeldså (2005). The birds of Machu Picchu and the Cusco region. Nuevas Imagenes, S. A., Lima, Peru. Close , 15 Freile, J., and R. Restall (2018). Birds of Ecuador. Bloomsbury, London, UK. Close ).

Earthworms, insects (including noctuid moth caterpillars), spiders ; fruits of cultivated trees.

Song , mainly at dawn and dusk and only in austral spring and summer, from high branch, telephone line or rooftop, sometimes described (Argentina) as very beautiful and melancholy (12 Jaramillo, A., P. Burke, D. Beadle, and J. Donoyan (2005). Aves de Chile: incluye la península Antártica, las islas Malvinas y Georgia del Sur. Lynx Ediciones, Barcelona, Spain. Close , 28 Walker, B., and J. Fjeldså (2005). The birds of Machu Picchu and the Cusco region. Nuevas Imagenes, S. A., Lima, Peru. Close ).

Song weak and relatively unmusical, a series of short and simple melodic phrases that end in jumble or twitter, each phrase repeated 2–3 times, “siblisirrilé seblesierrilli…”; similar to song of T. fuscater and, some individuals, also to T. serranus. Calls include typical clucking “duck-duck” or sharp “tchok-kiek” for contact, and a loud rapid “tsi-tsi-tsi” in flight. Also a long-drawn, high-pitched “wheen” or “kiiiu” in alarm (5 Collar, N. J. (2005). Chiguanco Thrush (Turdus chiguanco). In Handbook of the birds of the World, Volume 10: Cuckoo-shrikes to thrushes (del Hoyo, J., A. Elliott and D. A. Christie), Lynx Edicions, Barcelona, Spain. pp. 675. Close , 10 Collar, N. J., E. de Juana and G. M. Kirwan (2019). Chiguanco Thrush (Turdus chiguanco). In Handbook of the Birds of the World Alive (del Hoyo, J., A. Elliott, J. Sargatal, D. A. Christie and E. de Juana), Lynx Edicions, Barcelona, Spain. Available at https://www.hbw.com/node/58312. Close ). Race anthracinus (Argentina) described as a variable, rich, multisyllabic phrase of trills and modulated whistles lasting 1.2–2 seconds. Calls of anthracinus not known to differ northern races (6 Boesman, P. (2016). Notes on the vocalizations of Chiguanco Thrush (Turdus chiguanco). HBW Alive Ornithological Note 307. In: Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. Close , 7 del Hoyo, J., N. J. Collar and G. M. Kirwan (2019). Sombre Thrush (Turdus anthracinus). In Handbook of the Birds of the World Alive (del Hoyo, J., A. Elliott, J. Sargatal, D. A. Christie and E. de Juana), Lynx Edicions, Barcelona, Spain. Available at https://www.hbw.com/node/1344025. Close ).

Nesting biology of the northern two subspecies is surprisingly poorly known, with no descriptions of the nest and eggs available. Nesting biology of the southern anthracinus, however, has been reasonably well studied (29 de la Peña, M. R. (1987). Nidos y Huevos de Aves Argentinas. Published privately, Santa Fe, Argentina. Close , 30 de la Peña, M. R. (1999). Nidos y Huevos de Aves Argentinas. Fundación Hábitat y Desarrollo, Santa Fe, Argentina. Close , 31 Salvador, S. A. and L. A. Salvador. (1984). Notas sobre hospedantes del Renegrido (Molothrus bonariensis) (Aves: Icteridae). Historia Natural 4:121-130. Close , 32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ). In northwestern Argentina (anthracinus), only 10% of 35 nests were successful, predation being the main cause of failure (33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Fledglings in March, April, and July in Ecuador (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close , 34 Best, B. J., C. T. Clarke, M. Checker, A. Broom, R. M. Thewlis, W. Duckworth, and A. McNab (1993). Distributional records, natural history notes, and conservation of some poorly-known birds from southwestern Ecuador and northwestern Peru. Bulletin of the British Ornithologists’ Club 113(4):234–255. Close , 35 Best, B. J., M. Checker, R. M. Thewlis, A. L. Best, and W. Duckworth (1996). New bird breeding data from southwestern Ecuador. Ornitología Neotropical 7(1):69–73. Close ). Birds in breeding condition in Nov and Dec, nestbuilding in late Oct and a nest 10 m above ground in third week of Dec, and fledglings Jan and Apr–Jul in Peru (24 Koepcke, M. (1958) Die Vögel des Waldes von Zárate (Westhang der Anden in Mittelperu). Bonner zoologische Beiträge 9: 130–193. Close ,8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close ). January and March–April nests and fledglings in June, in northern Chile (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close ). Fledglings Jan–Feb and Apr in Bolivia (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close ). Nesting in Argentina mostly October-January, fledglings Mar–Apr (8 Fjeldså, J., and N. Krabbe (1990). Birds of the High Andes: A Manual to the Birds of the Temperate Zone of the Andes and Patagonia, South America. Zoological Museum, University of Copenhagen and Apollo Books, Copenhagen and Svendborg, Denmark. Close , 32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Nests generally built low, c. 1.2–6 m above the ground, in small tree or similar situation (at least six species utilized in NW Argentina)(32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Nest a solid cup of grass and slender twigs, often incorporating moss and mud into the structure of the nest, and lined with flexible fibers such as grass stems and rootlets (29 de la Peña, M. R. (1987). Nidos y Huevos de Aves Argentinas. Published privately, Santa Fe, Argentina. Close , 30 de la Peña, M. R. (1999). Nidos y Huevos de Aves Argentinas. Fundación Hábitat y Desarrollo, Santa Fe, Argentina. Close , 31 Salvador, S. A. and L. A. Salvador. (1984). Notas sobre hospedantes del Renegrido (Molothrus bonariensis) (Aves: Icteridae). Historia Natural 4:121-130. Close , 32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Eggs 2–3, pale greenish blue, with chestnut and gray spots and blotches (29 de la Peña, M. R. (1987). Nidos y Huevos de Aves Argentinas. Published privately, Santa Fe, Argentina. Close , 30 de la Peña, M. R. (1999). Nidos y Huevos de Aves Argentinas. Fundación Hábitat y Desarrollo, Santa Fe, Argentina. Close , 32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ). Size 32·4–34·2 mm × 23–24·2 mm (33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ). In a study in northwestern Argentina (anthracinus), mean clutch 2.6 eggs (33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Incubation 11–12 days, exclusively by female (33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Southern race, anthracinus, is a well-documented host of Shiny Cowbirds (Molothrus bonariensis) (31 Salvador, S. A. and L. A. Salvador. (1984). Notas sobre hospedantes del Renegrido (Molothrus bonariensis) (Aves: Icteridae). Historia Natural 4:121-130. Close , 32 Salvador, S. A. and L. A. Salvador (2012). Reproducción de aves de Pampa de Achala, Córdoba, Argentina. Historia Natural (tercera serie) 2:119-145. Close , 33 Vergara-Tabares, D.L. and Peluc, S.I. (2013). Aspectos de la biología reproductiva del Zorzal Chiguanco (Turdus chiguanco) en el Chaco Serrano de Córdoba, Argentina. Ornitología Neotropical. 24: 345–357. Close ).

Fairly common to common in most parts of its range, and a rather familiar species. Very widespread in Peru. Possibly expanding its range northern in Ecuador, since all records from Cotopaxi and Pichincha are post-1980 (26 Krabbe, N. (1992). Notes on distribution and natural history of some poorly known Ecuadorean birds. Bulletin of the British Ornithologists’ Club 112(3):169–174. Close , 25 Ridgely, R. S. and P. J. Greenfield. (2001). The birds of Ecuador. Ithaca, NY: Cornell University Press. Close ). Locally abundant in Bolivia (11 Hennessey, A. B., S. K. Herzog, and F. Sagot (2003). Lista Anotada de las Aves de Bolivia. Fifth edition. Asociación Armonía/BirdLife International, Santa Cruz de la Sierra, Bolivia. Close ). In Argentina, at least formerly (to 1950s), was taken for cagebird trade owing to fine singing voice (17 Partridge, W. H. (1953). Observaciones sobre aves de las provincias de Córdoba y San Luis. Hornero 10:23–73. Close ), but the species’ range appears to be currently expanding in northern Patagonia, with records as far south as southern coastal Chubut (36 Narosky, T., and D. Yzurieta. (1989). Birds of Argentina and Uruguay: a field guide. Zagier and Urruty Publications, Buenos Aires, Argentina. Close , 37 de la Peña, M.R. (1999). Aves Argentinas. Lista y Distribución. Literature of Latin America, Buenos Aires. Close ).