Largest reproductive organ for a bird
Oxyura vittata
42.5 centimetre(s)
Argentina (Cordoba)
The largest penis of any bird is that of the Argentine lake drake (Oxyura vittata) which has been measured everted and unwound at 42.5 cm (16.7 in). The base of this retractable penis is covered with spines, yet the tip is soft and brush-like. The use of the waterfowl penis as a means of sex and age identification of live birds is commonplace. The discovery was reported by Kevin G. McCracken of the Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks and published in Nature magazine on 13 September 2001.