Ruff
Calidris pugnax
The ruff has a distinctive pot-bellied appearance, with a small head, medium-length bill, longish neck and heavy body. It has long legs that are variable in colour, being dark greenish in juveniles, pink to orange in adults with some males having reddish orange legs only during the breeding season. In flight, it has a deeper, slower wing stroke than other waders of a similar size, and displays a thin, indistinct white bar on the wing, and white ovals on the sides of the tail. The species shows sexual dimorphism.
ID text from Wikipedia, CC BY-SA 4.0
Sanderling
Calidris alba
The sanderling is a small plump sandpiper, 18–20 cm (7–8 in) in length. Its weight ranges from 40–100 g (1+1⁄2–3+1⁄2 oz). The winter bird is very pale, almost white apart from a dark shoulder patch. This is the source of the specific name, alba, which is the Latin for "white". Later in the summer, the face and throat become brick-red. The juvenile bird is spangled black and white, and shows much more contrast than the adult.
ID text from Wikipedia, CC BY-SA 4.0
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