mallard duckling is yellow with streaks by the eyes.
mallard duckling is yellow with streaks by the eyes.
what type of duckling is yellow with streaks by the eyes?
mallard
both male and female mallards have distinct iridescent purple-blue speculum feathers edged with white, which are prominent in flight or at rest but temporarily shed during the annual summer moult. upon hatching, the plumage of the duckling is yellow on the underside and face (with streaks by the eyes) and black on the back (with some yellow spots) all the way to the top and back of the head. its legs and bill are also black. as it nears a month in age, the duckling's plumage starts becoming drab, looking more like the female, though more streaked, and its legs lose their dark grey colouring. two months after hatching, the fledgling period has ended, and the duckling is now a juvenile. between three and four months of age, the juvenile can finally begin flying, as its wings are fully developed for flight (which can be confirmed by the sight of purple speculum feathers). its bill soon loses its dark grey colouring, and its sex can finally be distinguished visually by three factors: 1)the bill is yellow in males, but black and orange in females; 2)the breast feathers are reddish-brown in males, but brown in females; and 3)in males, the centre tail feather (drake feather) is curled, but in females, the centre tail feather is straight. during the final period of maturity leading up to adulthood (6–10 months of age), the plumage of female juveniles remains the same while the plumage of male juveniles gradually changes to its characteristic colours. this change in plumage also applies to adult mallard males when they transition in and out of their non-breeding eclipse plumage at the beginning and the end of the summer moulting period. the adulthood age for mallards is fourteen months, and the average life expectancy is three years, but they can live to twenty.
mallard
bullet::::- nov 28, 2008，duckling 1.0 version released;









































bullet::::- sep 22, 2009, duckling 1.2 version released;









































bullet::::- mar 17, 2010, duckling released the first open source version on the sourceforge site.









































section::::goal.









































to enable resource sharing, data fusion and collaboration working among scientific team members.









































section::::communities.









































duckling had been used in 63 teams, including the bio-energy, the accelerator mass spectrometry instrument and the atmosphere monitoring.









































section::::references.









































bullet::::- kai nan, kejun dong, yongzheng ma, et al. the collaboration environment for e-science, e-science technology and application, 2008.1









































section::::external links.









































bullet::::- duckling downloading: http://duckling.sourceforge.net/









































bullet::::- duckling exhibition: https://web.archive.org/web/20100815223720/http://duckling.escience.cn/









































bullet::::- duckling space: https://web.archive.org/web/20100907104425/http://bbs.cnic.cn/duckling/
duckling (software)