Duck (Mottled)

This southern duck is a very close relative of the widespread Mallard. Recently, Mallard and Mottled ducks have been bread together, and so the distinctive male plumage, which among these birds enables females to identify mates of their own species, was gradually lost. After thousands of years of evolutionary change, the two sexes are colored alike.

Female (above) Male (below)

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The most distinct feature about Mottled Ducks is that the female has a dusky yellow bill.

 photographed in the wild at Naples, FL