The Green-winged Teal (Anas crecca) is considered as the smallest dabbler duck. The drake's brown head has a big green band with a white border. The female is different from other teals because of its smaller beak and its almost all-white under tail coverts that contrast with its spotted flanks. Green-winged teals, agile and fast in flight, have a green speculum bordered with buff in the front and with white in the back. The drake, part of the carolinensis species, is found in almost all North America and has a vertical white streak on the side. The crecca species, from Eurasia, does not have a white streak on the side, but has one on the scapulars. The crecca species is common in Aleutian Islands and in Pribilof Islands, but rarer in North America especially on the continent's east and west coasts. The North American species, carolinensis, is sometimes considered as a distinct species found all across Canada and from central United States to Alaska.
It migrates early in spring compared to its blue-winged cousin. This teal species lives everywhere there is water, as long as the flow is soft and that it can fulfill its needs in terms of food. In fact, it does not migrate to the South as long as humid zones high on food are not frozen. That way, its diet is composed of vegetal matter, seeds, micro-organisms filtered with its beak: insect larvae, crustaceans, and molluscs. During summer, green-winged teals prefer ponds, artificial water bodies, and lakes with lush vegetation. During winter, it goes on covert large water bodies, flat and sandy coasts, maritime-climate lagoons and marshes.
The green-winged teal usually builds its nest on stable ground, well-hidden in grass or bushes near water. Between April and June, the female lays 8 to 11 eggs that are sat on 25 to 30 days. The small precocial ducklings are already covered with down when they are born and ready to leave the nest to feed on their own with the help of their parents once their eggs have hatched.