Princess Beatrice's and Edoardo Mozzi's home under threat from bird flu outbreak

They have been gradually renovating the property, including the cattle shed, which has been tipped to be an option for Sarah Ferguson as she prepares to leave Royal Lodge.

Avian flu is a type of influenza that is highly harmful to domestic and wild birds, with a high mortality rate.

It can also infect mammals such as cattle and poses a threat to human health, but this is very rare.

Blenheim Communities, a Facebook page which shares updates about the estate and the surrounding area, alerted residents about the danger.

It said: "Sadly, today, an incidence of bird flu has been confirmed on our estate.

"Currently, we only have a case within the park, but we continue to monitor both the park and wider estate.

"We are working hard to limit the spread to the wider population by following Defra guidance and best practice.

"We know many of you walk the park and value local and visiting birdlife, and we want to thank those of you who have reported seeing an ill or dead bird."

The page noted that the message would be "distressing" for those in the area, but urged people to avoid any dead or ill birds.

Witney Town Council, the nearest town to Blenheim Palace, confirmed bird flu had broken out at the town's lake the day before.

A dead swan was tested for avian flu and came back positive.

A spokesman for the council said: "Witney Town Council is saddened to confirm that a deceased swan retrieved from Witney Lake has tested positive for avian (bird) flu - Avian Influenza (H5N1).

"We know how much our community cares about the wildlife at the lake, and this news will be upsetting for many.

"Please do not attempt to collect or touch dead birds, or birds that appear sick or behaving unusually."

If anyone sees dead birds in the area, they are urged to report them directly to Defra via its website or the helpline on 03459 335 577.

Fergie's linked move to the cattle shed came to light last week, with her proposed residency being dubbed the "granny annexe".

A source told The Mail: "The granny annexe seems to be ready to move into now. It'd be perfect for Fergie, wouldn't it?

"The stonework has all been repointed, the gutters renovated, the woodwork nicely painted. It has its own entrance. Just today, the road was blocked for a delivery of propane gas bottles for the annexe. That coincided with the first cold snap of winter.

"So, clearly, the arrival of someone is imminent. It may not look like much of a palace on the outside, but I bet it's stunning inside."

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