<p>
The Common Eider is a large sea-duck that is found on the
northern coasts of Europe, North America, and eastern Siberia.
</p>
<p>
They dive for mussels and crustaceans.  Mussels are swallowed
whole and their gizzard crushes the shell.
Crabs bodies are also consumed this way after the legs and claws
have been removed.
</p>