Observation date: 8 April 2019
Today, as close as I can figure, we should be in the twenty first day of incubation. Normal incubation for the peregrine falcon is 31-33 days. However, it is difficult to discern when egg laying is incomplete and incubation begins. When I have observed incubation exchanges, the tiercel spends 1 to 1 1/2 hours incubating eggs. The female 2 to 2 1/2 hours. This is due to the male having to bring food for both. In the early stages of incubation during exchanges, copulation has been observed which is normal during egg laying, but not so much during incubation.
A good guess would be egg hatching occurring around April 23rd and chicks should be visible two weeks later or first week in May. All of these dates and times are approximate and only done by observation from afar, since we are unable to see directly into the nest. So it is just a guess and don’t take it as gospel.
Happy trails, Bob
Item: Forgot to mention, they are not nesting in last years nest site, but have chosen the cathedral hole first used in 2001. That arched shaped hole was used by the newly arrived second pair of falcons to arrive at Morro Rock in 2001.
Thanks, Bob for keeping us in the loop. Great information and can’t wait to see those little guys!