Green-winged Teal, Anas crecca
An adult male Green-winged Teal in its beautiful full breeding plumage, above.
The less flamboyantly plumaged female, just showing a flash of the green speculum that gives the species its name. Females have evolved to be difficult for predators to spot, particularly when sitting on the nest, whereas male plumage is greatly influenced by sexual selection, the competition to be chosen as a mate by a female.
And here is a male who has succeeded in being chosen. See a similar waterfowl copulation by a pair of Northern Shovelers here, with the male likewise holding the female's nape in his bill.
A male in full breeding plumage out of water above, and another male still molting into breeding plumage, below, with the vertical white stripe just emerging. In summer, right after breeding season, while ducks are replacing their flight feathers and so are most vulnerable to predation, males molt into an eclipse plumage similar to the female's camouflage. Then through the fall they molt back into their bold breeding plumage, completing this molt by mid-winter; the transitional bird below was photographed in October, while the males on this page in full breeding plumage were all photographed in January.
