Green-winged Teal
Anas crecca
The Eurasian teal is one of the smallest extant dabbling ducks at 34–43 cm (13–17 in) length and with an average weight of 360 g (13 oz) in drake (males) and 340 g (12 oz) in hens (females). The wings are 17.5–20.4 cm (6.9–8.0 in) long, yielding a wingspan of 53–59 cm (21–23 in). The bill measures 3.2–4 cm (1.3–1.6 in) in length, and the tarsus 2.8–3.4 cm (1.1–1.3 in). From a distance, the drakes in breeding plumage appear grey, with a dark head, a yellowish behind, and a white stripe running along the flanks.
ID text from Wikipedia, CC BY-SA 4.0

Northern Pintail
Anas acuta
The northern pintail is a fairly large duck with a wing chord of 23.6–28.2 cm (9.3–11.1 in) and wingspan of 80–95 cm (31–37 in). The male is 59–76 cm (23–30 in) in length and weighs 450–1,360 g (0.99–3.00 lb), and therefore is considerably larger than the female, which is 51–64 cm (20–25 in) long and weighs 454–1,135 g (1.001–2.502 lb). The northern pintail broadly overlaps in size with the similarly widespread mallard, but is more slender, elongated and gracile, with a relatively longer neck and (in males) a longer tail.
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Green-winged Teal and Northern Pintail.