Cinnamon Teal
Spatula cyanoptera
The adult male has a cinnamon-red head and body with a brown back, a red eye and a dark bill. The adult female has a mottled brown body, a pale brown head, brown eyes and a grey bill and is very similar in appearance to a female blue-winged teal; however, its overall color is richer, the lores, eye line, and eye ring are less distinct. Its bill is longer and more spatulate. Male juvenile resembles a female cinnamon or blue-winged teal but their eyes are red. They are 16 in (41 cm) long, have a 22-inch (560 mm) wingspan, and weigh 14 oz (400 g).
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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