Swan Upping is the annual census of the swan population on stretches of the Thames in the counties of Middlesex, Surrey, Buckinghamshire, Berkshire and Oxfordshire. This year's Swan Upping began on Monday 19 July, departing from Sunbury Lock, Surrey, and ended at Abingdon, Oxfordshire, on Friday 23 July 2010. This historic ceremony dates from the twelfth century, when the Crown claimed ownership of all mute swans. This ownership is shared with the Worshipful Company of Vintners and the Worshipful Company of Dyers, who were granted rights of ownership by the Crown in the fifteenth century. In the Swan Upping ceremony, The Queen's Swan Marker, the Royal Swan Uppers and the Swan Uppers of the Vintners' and Dyers' livery companies use six traditional Thames rowing skiffs in their five-day journey up-river. The Queen's Swan Uppers wear traditional scarlet uniforms and each boat flies appropriate flags and pennants. When a brood of cygnets is sighted, a cry of "All up!" is given to signal that the boats should get into position. On passing Windsor Castle, the rowers stand to attention in their boat with oars raised and salute "Her Majesty The Queen, Seigneur of the Swans". The cygnets are weighed and measured to obtain estimates of growth rates and the birds are examined for any sign of injury (commonly caused by fishing hooks and line). The swans are also given a health check and ringed with individual identification numbers by The Queen's Swan Warden, a Professor of Ornithology at the University of Oxford's Department of Zoology. The swans are then set free again. Swan Upping takes place in the third week of July each year. ------------------------------------------ Original Photograph 21-Jul-2010