Comb duck
Comb duck | |
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male | |
female | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Anseriformes |
Family: | Anatidae |
Genus: | Sarkidiornis |
Species: | S. sylvicola
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Binomial name | |
Sarkidiornis sylvicola Ihering, HFA & Ihering, R, 1907
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Synonyms | |
Sarkidiornis melanotos sylvicola |
The comb duck or American comb duck (Sarkidiornis sylvicola), is an unusual duck, found in tropical wetlands in continental South America south to the Paraguay River region in eastern Paraguay, southeastern Brazil and extreme northeastern Argentina,[2] and as a vagrant on Trinidad.
Most taxonomic authorities split this species and the knob-billed duck from each other. The comb duck is generally smaller in size when compared to the knob-billed duck, and flanks are darker (black in males, medium grey in females).
Systematics
Uncertainty surrounds the correct
Analysis of
Description
This common species is unmistakable. It is one of the largest species of duck. Length can range from 56 to 76 cm (22 to 30 in), wingspan ranges from 116 to 145 cm (46 to 57 in) and weight from 1.03 to 2.9 kg (2.3 to 6.4 lb).[5][6][7] Adults have a white head freckled with dark spots, and a pure white neck and underparts. The upperparts are glossy blue-black upperparts, with bluish and greenish iridescence especially prominent on the secondaries (lower arm feathers). The male is much larger than the female, and has a large black knob on the bill.
If seen at a distance, immature comb ducks can also be mistaken for a fulvous whistling duck (Dendrocygna bicolor). However, knob-billed ducks in immature plumage are rarely seen without adults nearby and thus they are usually easily identified, too.[3]
Ecology
It breeds in still
This duck feeds on vegetation by grazing or dabbling[3] and to a lesser extent on small fish, invertebrates, and seeds. It can become a problem to rice farmers. Knob-billed ducks often perch in trees. They are typically seen in flocks, small in the wet season, up to 100 in the dry season. Sometimes they separate according to sex.[8]
Reproduction
Comb ducks nest mainly in tree holes,[3] also in tall grass. They line their nests with reeds, grass, or feathers, but not down.[8]
Males may have two mates at once or up to five in succession. They defend the females and young, but not the nest sites. Unmated males perch in trees and wait for opportunities to mate.[8]
Females lay seven to 15[3] yellowish-white eggs. Several females may lay in a single "dump nest" containing up to 50 eggs.[8]
References
- . Retrieved 19 November 2021.
- ^ Bencke, Glayson Ariel (2007): Avifauna atual do Rio Grande do Sul, Brasil: aspectos biogeográficos e distribucionais ["The Recent avifauna of Rio Grande do Sul: Biogeographical and distributional aspects"]. Talk held on 22 June 2007 at Quaternário do RS: integrando conhecimento, Canoas, Rio Grande do Sul, Brazil. PDF abstract
- ^ ISBN 0-7470-2201-1
- JSTOR 4089339.
- ISBN 978-1-84330-328-2
- ISBN 978-1-4008-3409-9.
- ^ Sarkidiornis melanotos (Comb duck, Knob-billed duck) Archived 2012-04-14 at the Wayback Machine. biodiversityexplorer.org
- ^ a b c d Honolulu Zoo (2007): Comb Duck Archived 2005-11-25 at the Wayback Machine. Retrieved 2007-06-08.