Despite the fact that many of us at the Cathedral watched the webcam avidly, no-one managed to spot the moment when the eggs were laid. The first one was spotted on Friday, 31 March and the second egg before dawn on Sunday, 2 April.

Generally peregrines lay between 3 and 4 eggs but this can vary. We have heard of instances where as many as six have been laid.

A high number of eggs doesn't guarantee breeding success. We've done some reading up on this subject and here's what the Sheffield Bird Study Group had to say on the subject in 2015. The author is Dr Nicola Hemmings of the Department of Animal and Plant Sciences at the University of Sheffield:

"Hatching failure is a common problem...in general, a small proportion of eggs (i.e. 1-2%) remain unhatched, but occasionally entire clutches fail. The extent of hatching failure varies markedly across birds and tends to be higher in endangered species. This year (2015), the Sheffield Peregrines experienced a fairly high level of loss: 50% hatching failure."

Dr. Hemmings explains that there are two main reasons why eggs fail - infertility or embryo death. We have been lucky so far but until the chicks hatch we are not into safe waters - and even then one never knows.

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