On the 15th April at approx 1100hrs the male peregrine was observed to be taking a turn at incubation. Looking at the two pictures below it is clearly possible to see the size difference between the two birds. At 1120hrs, we were able to video the birds swapping incubation duties.
The male bird in the nest tray at 1121hrs on 15th April 2011
The female bird in the nest tray at 1159hrs on 15th April 2011
Video from the 15th April 2011 showing the male and female switching over incubation duties.