单语范例（未经PONS编辑处理）
While this garnered 82 reports of the species, follow-up surveys of the area failed to find the shelduck.
en.wikipedia.org The species' common name is derived from the tuft of green feathers from the shelduck's head.
en.wikipedia.org A good number of rare duck species -- gadwall, mallard, ruddy shelduck and common pochard were spotted in the park this year, said an official.
www.hindustantimes.com The ruddy shelduck is a distinctive species, 5870 cm long with a 110135 cm wingspan.
en.wikipedia.org Two additional crested shelduck specimens are known to have existed, though both have been lost.
en.wikipedia.org