Fears over Thames swans
The annual "swan upping" count started today amid fears high waters levels in the Thames are stopping the birds breeding successfully.
The historic ceremony began today at Sunbury, led by David Barber, the Queen's Swan Marker.
Mr Barber and his team will spend five days rowing upstream counting swans and marking and weighing the cygnets.
He said last year saw significantly lower cygnet numbers than usual and expected the trend to continue this year.
Mr Barber said high water levels and strong currents early last month would have washed away many nests.
Swan upping dates from the 12th Century when the Crown claimed ownership of all mute swans, at the time regarded as tasty dishes at banquets and feasts.
The swans are no longer eaten but the ceremony is used as a chance to monitor swan breeding numbers.