Silkies or selkies are shape shifting sea fairies usually in the form of bright-eyed seals. They are localised to Northern Scotland and the Shetland Islands.
Silkies often came on to land in human form, where they would dance, especially on the night of the full moon.
In taking human form the Silkies shed their sealskin, and hide them in a safe place. There are many tales from the clans of leaders taking Silkie wives by stealing their skins. The Silkies are said to make good wives but always long for the sea, and return to their seal form if they gain repossession of their skins.
The silkies can be identified in their human form by their webbed fingers and toes and their ability to swim underwater for long periods of time.