Green-winged Teals (Anas crecca) are fairly common winter visitors and transients here in southeastern Arizona, but I have never seen very large flocks of these small dabbling ducks here. Green-winged Teals favor shallow ponds and wetlands with plenty of surrounding vegetation. I observed this male Green-winged Teal along with a female at the Sweetwater Wetlands here in Tucson in early January of 2007.
Male Green-winged Teals have gray sides with a vertical white stripe, a black bill, and a cinnamon-colored head with an iridescent green eye patch. The females are a much drabber mottled brown. Both sexes have an iridescent green wing patch, which is most visible in flight.