Males give a clear whistling call as part of several courtship displays, sometimes adding a rapid chitter. Green-winged Teal females give a repeated, shrill quack on the wintering grounds, during courtship, and to distract potential predators when brooding. They also give 5–15 fast, persistent quacks, about 2 per second, when searching for nest sites, perhaps to lure potential predators out and assess a site’s safety. A series of 4–7 quacks of decreasing volume is given during courtship, as well as a harsh, rattling call made when inciting a male during pair formation.
The Green-winged Teal’s wings make a whistling sound in flight.