The Blue-winged Teal (Anas discors) is an American species of duck. A vagrant to Britain, this bird is often blown over by strong winds. Named because of a pale blue patch on it's wing, which can be seen when this bird is flying, the male blue-winged teal also has a white cheek. About 1-13 records annually, but this may include escapes. It has a length of 37-41cm.
Blue-winged Teal - http://www.flickr.com/photos/qwertyqwertyqwerty/