Red Knot



Red Knot in South America

Scientific name: Calidris canutus rufa

Family: Scolopacidae

Spanish name: Playero rojizo

Migration: Nearctic migrant

Population estimate: 20,000-25,000

Trend: Decreasing

Ramsar Criterion 6 (1% level): 225

IUCN Conservation status: Not applicable at subspecies level.


Distribution and abundances

During the non-breeding season highly concentrated in southern Patagonia, with the majority of birds staying at Bahía Lomas (Chile) and other few coastal areas of Tierra del Fuego Island, where the species can be found from November to February. A separated population remains the whole non-breeding season in Maranhão, in northern Brazil. Abundances have declined notably since 2000, falling down from around 100,000 birds to 50,000 birds by 2000-2001 season, and to 24,000 birds by 2004-2005 season (link to Abundances map). Sites reaching the 1% threshold (Ramsar Convention Criterion No. 6) are: Rio Gurupi and Lagoa do Peixe in Brazil; Bahía Lomas in Chile, and Bahía San Antonio, Bahía San Sebastian and Península Valdés in Argentina.


Migration and seasonality

After the breeding season, knots fly non-stop from coastal North America to northern Brazil and then on through Argentina to Tierra del Fuego. Migration occurs mainly along the Atlantic Flyway. After leaving Tierra del Fuego in northward migration, knots are recorded in Argentina, Uruguay and southern Brazil (March/April); mayor known stop-over sites are in Rio Gallegos, Peninsula Valdés and Bahía San Antonio in Argentina and Lagoa do Peixe in southern Brazil. From there birds fly across Amazonia to northern coast of Brazil, before to fly non-stop to Delaware Bay. The northward migration to the Arctic is more time-constrained and demanding. Many immature birds remain in the wintering quarters (link to Seasonality map).



Strictly coastal, red knots inhabit large tidal mudflats / sandflats, sandy beaches, bays and salt marshes near the coast.


Habits and interactions with human activities

Highly gregarious, they concentrate in very high numbers at key stop-over sites along the coast, many times overlapping with areas with high human activities, mainly recreational and industries.



Antas, P.T.Z. 1983. Migration of nearctic shorebirds (Charadriidae and Scolopacidae) in Brasil ‑ flyways and their different seasonal use. Wader Study Group Bull. 39: 52-56.

Baker, A.J., P.M. González, I.L. Serrano, W.R.T. Júnior, M. Efe, S. Rice, V.L. D’Amico, M. Rocha, & M.E. Echave. 2005a. Assessment of the wintering area of red knots in Maranhão, northern Brazil, in February. 2005. Wader Study Group Bulletin 107: 10-18.

Bent, A.C. 1962. Life Histories of North American Shore Birds. Part I. Dover Publications INC. New York.

Canevari, P., G. Castro, M. Sallaberry & L.G. Naranjo. 2001. Guía de los chorlos y playeros de la Región Neotropical. ABC, WWF-US, WA, MBO & Asociación Calidris, Cali, Colombia.

del Hoyo, J., A. Elliott & J. Sargatal (eds). 1996. Handbook of the Birds of the World. Vol. 3. Hoatzin to Auks. Lynx Ed., Barcelona.

González, P.M., M. Carbajal, R.I.G. Morrison, y A.J. Baker. 2004. Tendencias poblacionales del playero rojizo (Calidris canutus rufa) en el sur de Sudamérica. Ornitología Neotropical 15 (Suppl.): 357-365.

Morrison, R.I.G. & R.K. Ross. 1989. Atlas of Neartic Shorebirds on the Coast of South America. Canadian Wildlife Service Special Publication, Ottawa.

Morrison, R.I.G. y B.A. Harrington. 1992. The migration system of the Red Knot Calidris canutus rufa in the New World. Wader Study Group Bulletin 64, Supplement: 71-84.

Morrison, R.I.G, R.K. Ross & L.J. Niles. 2004. Declines in wintering populations of Red Knots in southern South America. Condor 106: 60–70.

Ridgely, R.S., T. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, R.E. Young & R. Zook. 2003. Digital distribution maps on the birds of the Western Hemisphere. Version 1.0. Nature-Serve, Arlington, Virginia.

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.




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

Special contribution by: Patricia González

Data compiler: Eugenio Coconier

Photographer: Roberto Guller

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



Click on the link to download the factsheet in pdf format: Red Knot



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