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Comb Duck - BirdForum Opus

Photo © by Stanley Jones
Jaén, Cajamarca, Peru, January 2017
Sarkidiornis sylvicola

Alternative name: American Comb Duck


Photo © by Stanley Jones
Jaén, Cajamarca, Peru, January 2017

64–79 cm (25-31 in)

  • Glossy blue black upperparts
  • White underparts
  • Blue and green iridescent secondaries
  • White head with dark spots
  • White neck

Male - larger with large black knob on the bill

  • Dull buff underparts, face and neck
  • Dull brown upperparts, crown and eyestripe


Tropical South America (east of the Andes) to northern Argentina.
Has been reported as a vagrant on Trinidad.


This is a monotypic species1.
Formerly considered conspecific with Knob-billed Duck from Africa and Asia.


Young Male
Photo © by Dave B Smith
Trinidad, July 2010

Wetlands, freshwater swamps, rice fields and lakes.



The diet for both subspecies is mostly vegetarian, with grass, seeds and rice grain; supplemented with small fish and invertebrates.


They nest in tree holes and tall grass. The nest is lined with reeds, grass, or feathers. 7-15 yellowish-white eggs are laid; incubated by the female for about 30 days.


  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2018. The eBird/Clements checklist of birds of the world: v2018. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. Hockey, PAR, WRJ Dean, and PG Ryan, eds. 2005. Roberts' Birds of Southern Africa. 7th ed. Cape Town: John Voelcker Bird Book Fund. ISBN 978-0620340533
  3. Handbook of the Birds of the World Alive (retrieved June 2015)

Recommended Citation

External Links