Common Greenshank
Tringa nebularia
Common greenshanks are brown in breeding plumage, and grey-brown in winter. When in water, they can appear very similar to marsh sandpipers but are distinguished by the shape of the lower bill which gives it an upturned appearance to the bill. They have long greenish legs and a long bill with a grey base. They show a white wedge on the back in flight. They are somewhat larger than the related common redshank. The usual call is a rapid series of three short fluty notes syllabilized as teu-teu-teu. Like most waders, they feed on small invertebrates, but will also take small fish and amphibians.
ID text from Wikipedia, CC BY-SA 4.0

Common Redshank
Tringa totanus
Common redshanks in breeding plumage are a marbled brown color, slightly lighter below. In winter plumage they become somewhat lighter-toned and less patterned, being rather plain greyish-brown above and whitish below. They have red legs and a black-tipped red bill, and show white up the back and on the wings in flight. The spotted redshank (T. erythropus), which breeds in the Arctic, has a longer bill and legs; it is almost entirely black in breeding plumage and very pale in winter.
ID text from Wikipedia, CC BY-SA 4.0

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