Southern Wigeon




Southern Wigeon in South America

Scientific name: Anas sibilatrix

Family: Anatidae

Spanish name: Pato overo

Migration: Partial Neotropical migrant

Population estimate: 100,000–1,000,000 ([1])

Trend: Stable ([1])

Ramsar Criterion 6 (1% level): 10,000 ([1])

IUCN Conservation status: Not known to have unfavourable conservation status


Distribution and abundances

Distributes in southern South America, from Tierra del Fuego and the Malvinas / Falkland Islands to central Chile, northern Argentina, Paraguay, Uruguay and southern Brazil. Accidental in Peru. The highest abundances are recorded in the Patagonia of Argentina and Chile and within the Pampas (link to Abundances map). Important staging and moulting areas in the foothill east of the southern Andes. The unique site reaching the 1% threshold (Ramsar Convention Criterion No. 6) is Meseta de Strobel, in Santa Cruz province, Argentina (estimate of 18,900 birds).


Migration and seasonality

Southern populations migrate partially to the north in the winter, reaching Paraguay, Uruguay and south-eastern Brazil. Migration occurs along the western, central and eastern Patagonia routes (link to Seasonality map).



Lakes, large ponds, lagoons, marshes and broad rivers, preferring grassy and vegetated shores and shallows areas with submerged vegetation. Also in sewer lagoons and in the marine coast, close to the river mouths.


Habits and interactions with human activities

In small to medium flocks during the non-breeding season, sometimes in mixed groups with other duck species.



Canevari, M., P. Canevari, G.R. Carrizo, G. Harris, J. Rodríguez Mata & R. Straneck. 1991. Nueva Guía de las Aves Argentinas. Fundación Acindar. Santiago de Chile. Tome I: 200 pp. and Tome II: 182 pp.

del Hoyo, J., A. Elliott & J. Sargatal (eds). 1992. Handbook of the Birds of the World. Vol. 1. Ostrich to Ducks. Lynx Ed., Barcelona.

Fjeldsa, J. & N. Krabbe. 1990. Birds of the High Andes. Zoological Museum, Univ. of Copenhagen, Denmark.

Olrog, C.C. 1963. Lista y distribución de las aves argentinas. Opera Lilloana IX, Tucumán.

Olrog, C.C. 1968. Las aves sudamericanas: Una guía de campo. Tomo I. Universidad Nacional de Tucumán, Fundación - Instituto Miguel Lillo, Tucumán, Argentina.

Rodríguez Mata, J., F. Erize & M. Rumboll. 2006. Guía de Campo Collins – Aves de Sudamérica: No Passeriformes. Harper Collins Ltd.

Wetlands International. 2006. Waterbird Population Estimates – Fourth Edition. Wetlands International, Wageningen, The Netherlands.

Woods, R.W. & Anne Woods. 1997. Atlas of Breeding birds of the Falkland Islands. Anthony Nelson, England. 190 pp.




Authors: Daniel E. Blanco, Román Baigún & Bernabé López-Lanús

Data compiler: Eugenio Coconier

Photographer: Roberto Güller

Recommended citation: Blanco D.E., R. Baigún & B. López-Lanús. 2008. Southern Wigeon in South America factsheet. Wetlands International for the Global Avian Influenza Network for Surveillance / WCS / USAID.

([1]) South America population; not including the Falkland / Malvinas Islands (1,500-2,700 birds).



Click on the link to download the factsheet in pdf format: Southern Wigeon



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