The swan upping has been canceled for the first time in 900 years

An ancient and hallowed ceremony has fallen victim to the flood waters in England.

The "swan upping," an annual census of swans along the Thames, has been canceled, possibly for the first time in its 900-year history, according to the Guardian.

The ceremony dates back to the 12th century, when the crown claimed ownership over all mute swans, said the Guardian. It was due to start on Monday and continue all week, but Buckingham Palace announced on Monday that it would not be possible under the current weather conditions.

David Barber, the Queen's Swan Marker, said, "The flooding of the river between Sunbury and Windsor means that the water is very fast-flowing," according to the BBC.

"Boats aren't allowed on it at this time and it simply would not be safe to carry out the census. There's simply nothing we can do about it," he said.

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The Oxford Times said the rest of the week was in doubt as well, because the Environment Agency said the waters were too dangerous to navigate. "It is doubtful that Swan Upping can be rescheduled and we will probably have to wait until next year," said Barber.

According to the Guardian, the event involves hundreds of school children and volunteers and presents a colorful spectacle with the official swan uppers wearing traditional scarlet.

The first person to spot a brood of swans shouts, "All up!" That signals the other boats to get into position to catch the swans, which are then marked and checked for injuries.

As the swan uppers pass Windsor Castle, they stand at attention and salute "Her Majesty the Queen, seigneur of the swans," said the Guardian.

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Swans are now Crown property, according to The Oxford Times, and protected under the 1981 Wildlife and Countryside Act, though the swan upping initially originated from the fact that mute swans were a popular delicacy at banquets and feasts.

Earlier this year, The Daily Telegraph said many nests were swept away in floods and vandals shot the birds with air rifles and catapults, subjecting them to slow and painful deaths. The swans were also prone to fishing tackle injuries.

Last year's swan upping saw a 20 percent reduction in population thanks to the duck virus enteritis in early 2011, said The Telegraph.

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