A wild golden eagle rescued by a falconry expert has died after being seized by police and animal welfare officials.

Last November Roy Lupton, 34, a falconer from Hollingsbourne, Kent, was in Perthshire when a friend’s bird became locked in a fight with a wild golden eagle, one of Britain’s rarest birds of prey. There are 442 breeding pairs, mainly in Scotland.

Questions are being asked about the bird’s care at an RSPCA centre after it was confiscated from Roy Lupton, a falconer from Kent, who was nursing the eagle from injuries sustained in the wild.

The episode began in November last year when Mr Lupton, from Hollingsbourne, Kent, who keeps golden eagles and goshawks, set out with friends to take their birds to fly them in their natural habitat in Perthshire.

During the trip his friend’s female golden eagle became locked in a fight with a wild golden eagle. Mr Lupton, 34, a member of the Hawk Board, which represents 25,000 falconers, and an expert for Fieldsports TV, thought that the injuries to the wild bird were so serious that it would need veterinary treatment. It had suffered serious damage to the area of the chest where food is stored and near the eyes.

Mr Lupton sought permission from the Scottish Executive to remove the bird and nurse her at his specialist premises at Hollingsbourne. Without authority he would be liable to a £5,000 fine and up to six months in prison for removing a bird from the wild.

He planned to release the eagle in the spring. “I was concerned that the eagle, who I called Colin, was getting too used to humans,” he said. “It is important for these wild birds to be afraid of humans as it helps their protection in the wild. So I thought the best thing would be to fit a satellite monitor on the bird so conservationists could track her progress in the wild.”

Mr Lupton said that he told official from the Department for Environment, Food and Rural Affairs (Defra) about his plans. In May 5 his home and aviaries were raided by three officers from Kent Police, a policeman on secondment to Defra’s animal heath section and a wildlife crimes investigator from the Royal Society for the Protection of Birds.

“I explained everything to them but they were adamant they were going to remove the wild golden eagle and accused me of the illegal theft of the bird and keeping an unregistered bird,” he said.

“But what really appalled me is that they had no understanding of how to deal with such a bird. They brought the wrong box to carry the bird, I had to lend them one of my own.”

The bird was taken to the Mallydam wildlife centre in Sussex, run by the Royal Society for the Prevention of Cruelty to Animals. Mr Lupton was formally questioned by police, who passed the matter to the Crown Prosecution Service, but the case was dropped.

He was concerned about the eagle’s fate and was allowed to visit the premises with his vet. “I was horrified by what I saw,” he said. “The RSPCA was keeping the bird on a concrete floor, which is bad for its talons, and there was leaf mould on the roof of the room, which can cause lung infections in golden eagles.”

A month later he was allowed to take the bird home. Her condition had badly deteriorated and his local vet took blood tests. The bird was found to be suffering lead poisoning and Mr Lupton learnt that it had been fed on rabbits which had been shot with lead pellet.

On June 17 he took the bird to a centre in Swindon run by Neil Forbes, an avian veterinary surgeon. The eagle died 12 hours later.

In his autopsy report, Mr Forbes said that the bird was kept in inappropriate conditions while in the care of the RSPCA and was “not provided with good practice in terms of husbandry”.

He said: “Whilst I cannot be certain the bird’s death was a direct result of the Defra seizure and the period of RSPCA care, certainly the stress effect (suppressing the immune system), the persistent systemic infection from the time of leaving the RSPCA care, does indicate a very high likelihood of a causative link between the period of care and the bird’s subsequent death.”

The Hawk Board is demanding answers from Defra about the events.

Defra said that it could not comment on details as the case was subject to an internal investigation. “Animal health officers, with Kent Police, attended a falconry in Kent in the belief that the person in question did not have the correct paperwork for the eagle,” it said.

The RSPCA said: “Staff were extremely upset to hear about the death of this eagle and the society agrees this is a very sad and tragic event.” It said that it had had only two days’ notice to make preparations for the bird and during its stay staff raised concerns that it might have had underlying health problems.

The RSPB said that it was concerned about the eagle’s death and hoped that Defra would learn lessons from the incident.

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