Swan Upping

Swan Upping is an annual ceremonial and practical activity in Britain in which mute swans on the River Thames are rounded up, caught, marked, and then released.

Traditionally, the British Monarch retains the right to ownership of all unmarked mute swans in open water, but only exercises ownership on certain stretches of the River Thames and its surrounding tributaries. This tradition dates from c. the 12th century; It was formalised with a Royal Charter of Edward IV passed in 1482, establishing "How much land he must have which shall have a mark or game of swans", preventing the claim of ownership of swans by "yeomen and husbandmen, and other persons of little reputation".