KOCH JC (1940) Short announcements: Special food of various birds. LIMOSA 13 (1): 102-102.

Whooper Swan Cygnus cygnus Mallard Anas platyrhynchos Common Pochard Aythya ferina Tufted Duck Aythya fuligula Greater Scaup Aythya marila Common Goldeneye Bucephala clangula

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