1636.

Swans were royal birds, the property of the monarch, but from the 13th century the crown granted rights of ownership of swans to members of the public, with the flock of birds concerned being identifiable as the property of each grantee by a unique "swan mark" attributable to that person notched onto the beak of each swan in that person's ownership. The mark thus protected the grantee's birds from being taken to supply the royal dinner table, as was the potential fate of any unmarked swan found at large on a river within the kingdom.