The Bar-tailed Godwit (Limosa lapponica) looks very similar to the Black-tailed Godwit (Limosa limosa), especially when it is not flying.
In flight, however, the Bar-tailed Godwit is easy to recognize by its barred tail (instead of black-tailed), the long white patch on its back (instead of just a small white 'square"), no white wingbars and legs that don't stick out as much as they do with the Black-tailed Godwit.
In addition, the Bar-tailed Godwit has shorter and darker legs than the Black-tailed Godwit and the Black-tailed Godwit has a straight bill while the Bar-tailed Godwit has a slightly upturned bill which is also darker.
In winter plumage, the Bar-tailed Godwit has black stripes on its back and wings which lack on the Black-tailed Godwit.

In summer plumage, the male Bar-tailed Godwit is a warm reddish brown from head to tail; the female is much lighter. 
In winter plumage, both male and female are almost white below and light brown above.

Bar-tailed Godwits breed in the Arctic; in Europe it is in northern Scandinavia and Russia.
After the breeding season, Bar-tailed Godwits migrate south, the Scandinavian ones to the coasts of western Europe, the Siberians move further away and even move to African wetlands.
Large groups from Siberia and Alaska travel as far south as the coasts of Australia and New Zealand.

Bar-tailed Godwits occur in the Netherlands only in winter and during migration.
The numbers peak during the migration, especially in August-September and in May.
The species is strongly bound to salty and brackish waters.

1st & 2nd photo: Colijnsplaat, Haven, Noord-Beveland, The Netherlands, 13 January 2021
3rd photo: Colijnsplaat, Haven, Noord-Beveland, The Netherlands, 28 February 2011
4th photo: Texel, The Netherlands, 18 April 2012
5th photo: Texel, The Netherlands, 19 October 2018