Somateria mollissima
The Eider is the fasted flying duck in the UK, this may come as a surprise as it's also the heaviest duck too.
The males and females look considerably different with the male species being black and white all over, whilst the females are brown and black.
Eiders are rarely found away from the coast as they depend on a diet of shellfish, especially mussels. They are highly sociable birds and mainly stay close to the shore, simply riding the waves.
Their diets mainly consist of shellfish, predominately mussels.
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