From examining the Twitter feed, the eggs were laid on April 8, 11, 13, 16, and 18.
From http://www.allaboutbirds.org/guide/Barn_Owl/lifehistory we see that incubation is 29-34 days. If incubation starts with the laying of the first egg, the earliest date we can expect an owlet is May 7. If hard incubation is delayed and starts with the laying of the third egg (which happens in some raptor species), then May 12 will be the beginning of hatch watch.
I’d like to share with you my personal history with this particular cam. Back in 2011 is when I discovered my first nest cam, and this was it. When I first saw them, there were three owlets, two large and one small. No this was not due to the larger ones being female and the smaller being male, as one RTH mod was quick to inform me when I told this story on that chat. It was due to hatching asynchrony, which occurs because incubation of the eggs starts right after laying rather than being delayed until all (or most) of the eggs are laid. The owlets hatch a couple days apart and the oldest end up larger than the youngest for a while. If you look at the five owlets there now, there is a big difference in size between the largest and the smallest. If there is a shortage of food, the youngest will not be able to compete with its siblings and may starve to death. If it does, the body is not wasted; it will be fed to the others. Luckily there appears to be plenty of food so far for this batch. (Sorry for this short digression.)
Back then the picture was not nearly as clear as it is now. I think it was just in black and white and did not have many frames per second. Two things I remember clearly: there was not a lot of prey and it was very hot. The owlets and mom did lots of gular fluttering. The pantry where prey is stored is just behind the partition, so we can’t see it. There was a chat and I learned a lot about what was going on from reading there (although I don’t think I was brave enough to join in).
One day a large snake entered the box. I seem to remember reading that it was a constrictor type of snake, perhaps a King Snake. We couldn't see very well what was going on, but mom somehow attacked the snake and made it leave. This was very brave of her (I know, anthropomorphizing again) since she could have been killed by the snake herself. When the snake was gone, all the owlets were completely still, perhaps from fright, perhaps it’s a defense strategy, perhaps mom gave a command for them to freeze (this does occur in some birds). Eventually two of the three started moving again, but one of the larger ones had somehow been killed. The mom tried to incubate it for a while. Eventually she gave up and fed the body to the other two. It may seem harsh, but in times of prey shortage it really is the best thing for the others.
After that incident I read that the nest box owners were going to put up some kind of snake barrier. I hope they have one in place now. I believe the following year or two there were no owls nesting in the box and it was thought the snake incident may have had something to do with those parents choosing a different location.
Snakes?? Thanks for sharing your story, Alta. Very interesting. It's amazing all the natural dangers out there that the wildlife deal with on a moment to moment.
The human spirit needs places where nature has not been rearranged by the hand of man. ~~ Author Unknown
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Wed Apr 02, 2014 3:28 pm
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I love them all 
Dad's talons.PNG - Bild entfernt (keine Rechte)
Pretty lady.PNG - Bild entfernt (keine Rechte)
Hoping for a successful year here this time.