In Pictures: Britain's Royal Swan Uppers conducting swan census along the Thames

Swan Upping is a yearly activity in Britain in which mute swans along the Thames River are caught, assessed and then released. During this week-long activity, Royal Swan Uppers, dressed in the scarlet uniform of Her Majesty The Queen, row up and down the river in skiffs, which are traditional wooden rowing boats, as they pick up swans and young cygnets. The swans are tagged to establish a swan census. Injured swans are also treated during this exercise. The tradition of swan upping dates back over 900 years to the 12th century.