A great bustard egg has been laid in Britain for the first time since Queen Victoria was a child, conservationists said yesterday.

The world’s heaviest flying bird died out in this country about 175 years ago but is being reintroduced through batches of chicks imported from Russia.

One bird chose a spot on Salisbury Plain to lay two eggs this spring – a year earlier than ornithologists had expected. The eggs have not hatched but their existence is being interpreted as a positive indication that the birds will soon breed successfully.

It is estimated that the last great bustard egg was laid in Britain in 1832. The birds, which can weigh up to 30lb (13.5kg), stand 4ft tall and have a wingspan of 8ft (2.4m), were hunted to extinction in Britain by man and foxes. They were described by one 19th-century ornithologist as “the largest, noblest and most highly prized of all our British birds”.

David Waters, a retired policeman and director of the Great Bustard Group (GBG), began importing annual batches of 25 to 40 chicks in 2004.

He said that the eggs were laid at an undisclosed location on the plain during the spring but their existence has been kept secret until now, in case of egg thieves or disturbance from bird-watchers.

Mr Waters said: “This is enormously exciting and a huge milestone in the quest to return this magnificent bird to Britain. It had been thought that 2008 would be the first year that nesting activity would be seen and it is a tremendous boost that it happened earlier. The eggs were incubated by the female but then abandoned and, after examination, found to be infertile.

“Significantly, only birds in good condition produce eggs. Hungry or stressed wild birds do not produce eggs so this is a strong indication of the success of the project.”

Mr Waters, whose compound is based on the edge of the plain, said normally the birds had to be 5 years old before they could breed, and these would have been aged 3 or 4.

Their youth was the probable reason that the eggs were not fertilised, he added.

Several months ago male bustards were seen in the spectacular act of displaying to a female – a strutting, feather-flexing performance which normally precedes mating.

A fifth batch of great bustard chicks is due to arrive from Russia imminently. The birds are released on Salisbury Plain, their last stronghold before extinction in Britain, and each autumn and winter they move away before those still alive return in the spring.

Mr Waters said: “This year more than ever have made the return journey, including two males which had not been seen anywhere for more than 18 months.”

GBG project officer Al Dawes said: “Great bustards are notoriously shy and secretive birds so keeping track of them is a big challenge.

“It is a credit to farmers and landowners that they keep us informed of the birds’ whereabouts, which led to the discovery of the nest this spring.”

Hunted when wet

— Males gather in groups called leks to attract females

— The diet is seasonal and opportunistic. They will eat insects such as grasshoppers, plus cereal seeds

— The bird needs a mixture of chalk grass-land in the summer and farmland in winter

— Its tasty meat, size and rarity meant that it was prized by hunters in the 19th-century. After rain or heavy dew, when the water-sodden birds had difficulty getting airborne, hunters would chase the birds on horseback with packs of greyhounds

— The great bustard is the county bird of Wiltshire

Sources: RSPB and National Geographic

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