Argentine rowing duck
| Argentine rowing duck | ||||||||||
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Argentine rowing ducks in the Heidelberg Zoo |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Oxyura vittata | ||||||||||
| ( Philippi , 1860) |
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The lake duck ( Oxyura vittata ), also Argentine Ruddy Duck or binding Ruderente called, is a breeds of ducks from the subfamily of the oxyurinae .
features
Argentine rowing ducks reach a body length of about 35 to 40 centimeters and a weight of about 640 grams. Females and males in resting plumage are sooty-brown to blackish with yellow-brown to reddish wave markings. A yellow-brown to whitish stripe runs under the eye from the base of the dark-gray beak to the nape of the neck, under which there is a lightly speckled dark band. The neck is whitish, often with a darker mottled or speckled nape. The ventral side is silvery-white with brown spots, legs and feet are dark gray.
In the magnificent dress , the male has a completely black colored head. The body is reddish-chestnut brown, the wing feathers, the tail and the region between the shoulders are sooty-brown to blackish in color. The belly side is speckled dirty-white, whereby the chestnut brown color on the back is sometimes clearly incorporated into the color of the abdomen. The beak is brightly blue, the iris of the eye is reddish brown. Legs and feet are blue-gray.
While most bird species have no external mating organ at all, the males of the Argentine rowing duck have an exceptionally large penis , which when at rest lies rolled up like a corkscrew in the cloaca and reaches an average length of a little over 20 centimeters. One specimen even measured 42.5 centimeters when fully extended. The penis, which is coiled even when extended, is mottled gray and has a series of coarse spines at the base, while the end is soft and brush-like. How exactly the organ is used during mating is unknown. It has been speculated that it serves a display function or, since rowing ducks show pronounced promiscuity , serves to remove sperm deposited in the female genital tract during previous matings .
Occurrence
The Argentine rowing duck populates ponds and lakes with rich aquatic vegetation in the plains of temperate South America . It breeds in Chile from the Atacama Desert to Tierra del Fuego as well as in Argentina and winters in Paraguay , Uruguay and southern Brazil .
swell
- Emmet Reid Blake: Manual of Neotropical Birds: Spheniscidae (Penguins) to Laridae (Gulls and Allies) . University of Chicago Press, Chicago 1977, ISBN 978-0-226-05641-8 , pp. 257 .
Web links
- Videos, photos and sound recordings of Oxyura vittata in the Internet Bird Collection
- Oxyura vittata onthe IUCN Red List of Threatened Species .
- Michaela Simon: Well, size matters! Argentine rowing duck baffles scientists. In: Telepolis. September 13, 2001.
Individual evidence
- ↑ a b Emmet Reid Blake: Manual of Neotropical Birds: Spheniscidae (Penguins) to Laridae (Gulls and Allies) . University of Chicago Press, Chicago 1977, ISBN 978-0-226-05641-8 , pp. 257 .
- ↑ Kevin G. McCracken, Robert E. Wilson, Pamela J. McCracken, Kevin P. Johnson: Sexual selection: Are ducks impressed by drakes' display? In: Nature . tape 413 , 2001, p. 128 , doi : 10.1038 / 35093160 ( online ( memento of February 10, 2012 in the Internet Archive ) [PDF; accessed on December 23, 2015]). Sexual selection: Are ducks impressed by drakes' display? ( Memento of the original from February 10, 2012 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Kevin G. McCracken: The 8-inch Spiny Penis of the Argentine Lake Duck (Oxyura vittata) . In: The Auk . tape 117 , no. 3 , 2000, pp. 820–825 ( PDF, online [accessed April 9, 2006]). PDF, online ( Memento of the original from July 5, 2008 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
