Peter Hunt: "The operation was a complete success"

The operation on the 20-year-old creature's eyes is thought to be a world first for the species and was declared a success.

It was paid for by an appeal which raised £2,000 in just two weeks.

The operation was carried out by vet Paul Evans who works in the village of Eye, near Leominster, Herefordshire. But the operation had to be curtailed in one of his eyes.

Cataracts reduced to liquid

"I think he's had a cataract for a long time - three years," said Mr Evans. "Had we gone any further we may have caused more damage to the eye so we stopped."

As a result one eye will be better than the other.

The cataracts were reduced to liquid with a fine laser needle vibrating at 40,000 times a minutes and then sucked out.

Boris, whose sight will be blurred for a few days, will be returned to Tom and Carolyn Screech, who run an owl sanctuary in Cornwall.

"He can't fly very well because he can't see where he's going for a start," said Mr Screech.

"He has a job to find food so it's definitely knocked his confidence."

One eye will be better than the other

When his sight is fully restored he will be able to fly around his aviary and will also be back in the breeding game.

There are believed to be only 200 pairs of Siberian eagle owls in the world and Boris is one of only five of the species in captivity in Europe.

With his sight he has a life expectancy of 70 and could breed for another 20 years.

Mr and Mrs Screech are now planning to use money left over from the appeal to enable a female Siberian eagle owl from Moscow Zoo to come to the UK and mate with Boris.