Poultry rustlers have stolen an entire flock of organic free-range geese intended for the Prince of Wales’s Duchy Originals brand.

The thieves herded 350 Wessex white geese into a lorry before setting fire to the barn in Devon where they had been kept, killing 800 ducklings.

The Prince has written to Rona and Nevil Amiss, the owners of the farm, expressing his dismay. Duchy Originals will now be unable to supply any organic geese to Sainsbury’s this Christmas.

The birds were seven months old, weighed between 10lb (4.5kg) and 20lb and would have sold for about £50 each. The 800 ducklings were worth about £15 each. The total loss of poultry is about £30,000.

Mr and Mrs Amiss, who have been supplying Duchy Originals with geese for six years, said that they could not face keeping free-range poultry again. Mrs Amiss said that their young children watched in horror as the ducklings died. It was only after firefighters had put out the blaze that they realised that the geese were missing.

Mrs Amiss, 40, said: “I don’t understand how anybody could commit such a despicable, evil act. It is such a senseless loss and has been terrible for the whole family, our workers and the community.

“We woke at 4am to find the barn on fire - there was very little we could do by then. Four of the children were awake and had to watch as the creatures they helped to rear died in a horrible way.”

Police believe that the barn was set alight to destroy evidence and provide a distraction while the thieves made their escape.

The Amisses moved to the 57-acre Higher Fingle Farm in Crockernwell, in 2001, having previously farmed on Exmoor. They supplied organic free-range poultry to the public and wholesalers.

Mrs Amiss believes that the thieves singled out the farm months ago and were waiting for the right moment. The birds were due to be slaughtered and plucked the next day, December 1. “This is the third time we have been targeted by thieves during our career. Now we have decided the stress and fear are too much and we will no longer supply geese. Fire is such a serious thing and we have a family to think about. If the wind had been blowing the wrong way we could have lost a lot more.

“I have written to Prince Charles to tell him we can’t do it any more. We received a reply from his private secretary expressing their regret and support. It was very touching.”

She said that their children, Elsa, 9, Alfred, 7, Dora, 4, and Percy and Harold, 3, were devastated. “They all help out on the farm and had spent time with the birds. They knew the geese and ducks would be killed eventually, but that is part of the farming process and it is done humanely, in a way they understand.”

Duchy Originals, which was set up by the Prince of Wales in 1992, is a leading organic and natural food brand with retail sales of £40 million a year. A spokesman said: “This is a heartbreaking incident for the Amiss family, who have worked so hard and passionately to raise their geese organically and to the highest welfare standards.”

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