Masked Duck

Masked Duck
Adult male in breeding plumage
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Subclass:	Neornithes
Infraclass:	Neognathae
(unranked):	Galloanserae
Order:	Anseriformes
Family:	Anatidae
Subfamily:	Oxyurinae
Genus:	Nomonyx Ridgway, 1880
Species:	N. dominicus
Binomial name
Nomonyx dominicus (Linnaeus, 1766)
Synonyms
Oxyura dominica

The Masked Duck (Nomonyx dominicus) is a tiny stiff-tailed duck ranging through the tropical Americas. They are found from Mexico to South America and also in the Caribbean. Primarily non-migratory, Masked Ducks are reported as very uncommon vagrants in the southernmost United States, along the Mexican border and in Florida.

The only member of the genus Nomonyx, it is intermediate between the rather primitive Black-headed Duck (Heteronetta) and the very apomorphic true stifftails. It is sometimes included with the latter in the genus Oxyura, but apparently the Masked Ducks of our time are the descendants of a missing link in the Oxyurinae evolution, having changed but little for millions of years.^[1].

Breeding adult males have a rust-colored body with a black face and mottled wings. Adult females, winter males and juveniles have a barred brownish gray body, with 2 horizontal darkly colored stripes running through the buffy colored face.

These ducks mainly feed on seeds,roots and leaves of aquatic plants. They also eat aquatic insects and crustaceans. They feed by diving. Masked Ducks breed in any freshwater water body with marsh vegetation and surrounded by heavy tree cover. They also occur in mangrove swamps. These ducks are usually very secretive, but they are not rare and not considered threatened by the IUCN^[2].

Footnotes

1. ^ Livezey (1986), McKracken et al. (1999)
2. ^ BLI (2004)

References

• BirdLife International (BLI) (2004). Nomonyx domnicus. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006. Database entry includes justification for why this species is of least concern
• del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (eds.) (1992): Handbook of Birds of the World (Volume 1: Ostrich to Ducks). Lynx Edicions, Barcelona. ISBN 84-87334-10-5
• Livezey, Bradley C. (1986): A phylogenetic analysis of recent anseriform genera using morphological characters. Auk 103(4): 737-754. DjVu fulltext PDF fulltext
• McCracken, Kevin G.; Harshman, John; McClellan, David A. & Afton, Alan D. (1999): Data set incongruence and correlated character evolution: An example of functional convergence in the hind-limbs of stifftail diving ducks. Systematic Biology 48: 683-714. doi:10.1080/106351599259979 PDF fulltext
• National Geographic Society (2002): Field Guide to the Birds of North America. National Geographic, Washington DC. ISBN 0-792-26877-6
• Sibley, David Allen (2000): The Sibley Guide to Birds. Alfred A. Knopf, New York. ISBN 0-679-45122-6