Blue-winged Teal
Spatula discors
The blue-winged teal is 40 cm (16 in) long, with a wingspan of 58 cm (23 in), and a weight of 370 g (13 oz). The adult male has a greyish blue head with a white facial crescent, a light brown body with a white patch near the rear and a black tail. The adult female is mottled brown, and has a whitish area at base of bill. Both sexes have sky-blue wing coverts, a green speculum, and yellow legs. They have two molts per year and a third molt in their first year. The call of the male is a short whistle; the female's call is a soft quack.
ID text from Wikipedia, CC BY-SA 4.0
Garganey
Spatula querquedula
The adult male is unmistakable, with its brown head and breast with a broad white crescent over the eye. The rest of the plumage is grey, with loose grey scapular feathers. It has a grey bill and legs. In flight, it shows a pale blue speculum with a white border. When swimming it will show prominent white edges on its tertials. His crown (anatomy) is dark and his face is reddish brown. Some care is needed in separating the brown female from the similar common teal, but the stronger face markings and more frequent head-shaking when dabbling are good indicators.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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