Annual Census Of The Swan Population Takes Place On The Thames

LONDON - JULY 14: The Queen's Swan Marker, David Barber and his crew row along The River Thames during the annual swan upping, an event which takes place during the third week of July on the River Thames near Windsor on July 14, 2008 on the River Thames in London, England. During Swan Upping, the historic ceremony that dates from the 12th century, the Sovereign's Swan Marker, David Barber, counts the number of young cygnets on the river each year and ensures that the swan population is maintained. The swans and young cygnets are also assessed for any signs of injury or disease. (Photo by Daniel Berehulak/Getty Images)