What are the swans of the River Thames?
The mute swans on the River Thames are traditionally associated with the British monarch, who has the right to claim ownership of unmarked mute swans in open water. Each July, the swans are counted in a ceremony called Swan Upping.
The tradition dates back to the 12th century, when swans were valued as food for royal feasts.
Today, the monarch shares ownership of swans on parts of the Thames with two livery companies, the Vintners and the Dyers.
Swan Upping
During Swan Upping, the King's Swan Marker and teams in traditional rowing boats travel up the Thames, catching, weighing and checking cygnets and adult swans.
Today, Swan Upping is mainly used for conservation, monitoring the health of the swan population and educating schoolchildren.
It is illegal to harm mute swans in England. They are protected under the Wildlife and Countryside Act 1981.
Mute swans are large white birds with orange beaks. Despite their name, they make hissing and grunting sounds.
Swan Upping takes place over five days in the third week of July.