Blue-winged Teal Blue-winged Teal Anas discors - Female. Length 37-40cm. A small distinctive North American duck. Adult male has a bluish head with a striking and diagnostic white crescent. The body is buffish-brown, marbled with darker spots, and a white patch can be seen on the otherwise black stern. Adult female and juvenile are mainly marbled brown and are similar to their Teal counterparts. However, the plumage is greyer; note the pale spot at the base of the bill and the absence of a pale patch at the side of the base of the tail (seen in Teal). In flight, all the birds reveal an extensive and diagnostic blue panel across much of the upper surface of the inner wing. Ten or so individulas might be recorded in a good year, mainly in autumn and winter. Blue-winged Teals favour freshwater wetlands and occur in similar habitats to those frequented by migrant Garganeys in spring and summer.