Conservationists behind a plan to help two peregrines nest on the spire of Norwich Cathedral said despite the disappointment of an egg failing to hatch this year they are confident the pair will produce chicks next year.

The birds of prey were given a special nesting platform on Norwich Cathedral after they were spotted flying near the landmark last year.

Secured on the cathedral's spire, 250ft above the city streets, the platform provides a perfect spot where the pair can breed and hunt.

But an egg laid by the pair has failed to hatch successfully after the egg shell broke at 1am Monday morning revealing a dead chick.

The female laid the egg, on Easter Sunday, on a nest platform installed by conservation charity the Hawk and Owl Trust in February.

Leanne Thomas, from the Hawk and Owl Trust said because the female was still a juvenile the fact that she laid an egg at all was a great surprise.

'Though sad, the failure of an egg is not unusual,' she said. 'Unfortunately as the female peregrine was immature and only laid a single egg this year, there were no others to hatch successfully. Peregrines usually lay up to four, sometimes five eggs.'

Many people have been following the fortunes of the peregrines from the watch point on the lower close green at the Cathedral or via the webcam on the Hawk and Owl Trust and Norwich Cathedral websites.

Miss Thomas said that despite the disappointment this year, all the signs were good for 2012.

'Now that the male peregrine has set up territory and he is strongly bonded with the female bird it is probable that they will both stay at the cathedral,' she added. 'The female should be mature enough next spring to breed successfully so it is hoped that their practice run this year will result in a full clutch of eggs on the platform next April.'

The Hawk and Owl Trust and Norwich Cathedral will continue to work in partnership to monitor the peregrines and visitors to the Cathedral will be able to watch the sky around the spire for them.

The webcam will be switched off shortly but will be restarted if the birds nest again next spring. In the meantime people can watch nesting marsh harriers on the Hawk and Owl Trusts website www.hawkandowl.org and recordings of the Norwich Cathedral peregrines are available at www.hawkandowl.org/NorwichVideo.