A quick update on the laying of the third egg this morning, with another gap of around 60 hours between eggs. One egg was left out in the (not so) cold by the brooding female late morning, but this is not a cause for concern as the eggs are quite hardy and can be left uncovered for several hours at a time. Even when they are left uncovered, rest assured that the adults will be nearby to protect the nest from Crows or gulls, both of which could potentially take an egg. If you’re down at St George’s and see the Peregrines chasing either of these, that’s why it is.
The male flew in several times during the morning and screeched at the female, apparently looking to take over brooding duties. At around midday she moved aside and he took over, the three eggs already proving a challenge for his smaller size.
After some rolling of the eggs into place with his bill he settled down for a stint. At the current rate, it’ll probably be the weekend before any more eggs are laid, although a brood of three would also be quite normal. Ratcliffe’s seminal study (1993) found an average brood size of 3.65 based on over 400 clutches, with four eggs representing about 15% of a female’s body weight. Whether or not any more are laid we’ll have to wait and see!