19 March 2024
This morning Carla laid her third egg of the 2024 season at 2:01am. Because her nest is visible on a timestamped camera, I can tell you she laid the 3rd egg 52.87 hours after Egg#2. (Egg#2 was 53.14 hours after Egg#1.)
Here’s a video of the egg-laying moment, sped up to double-time, which happens to make it obvious.
By 6:29am Carla had been off the eggs for 90 minutes (standing up). That’s a very long time to be off the eggs if she had already started incubation because they would cool dangerously in this morning’s freezing weather.
Peregrine incubation begins when the female has laid her next-to-last egg but it is always hard to tell when it truly starts if the weather is cold because the adults cover the eggs to keep them from freezing. When incubation truly begins, the parent exposes the brood patch and lays its bare skin against the eggs. Peregrines can vary how much skin is exposed thus delaying the actual start of incubation until the clutch is nearly complete.
Learn more about the parents’ roles in incubation here. By the way, the bird covering the eggs on recent mornings has been Ecco.
Watch the Pitt peregrines on the National Aviary Falconcam at Univ of Pittsburgh.
p.s. Happy Spring Equinox tonight: 19 March 2024 at 11:06pm.
(photos and video from the National Aviary Falconcam at Univ of Pittsburgh)
Another one for Carla and Ecco! The nesting season at Pitt is off to a great start!
Thanks for the update, Kate.
The whole camera situation is so much better. Bravo!
Carla has been incubating the eggs since yesterday. She has been laying on them all afternoon yesterday & last night as well. I believe I also saw her laying on the eggs Sunday afternoon or early evening as well
Joann, Thank you for pointing that out. It’s actually hard to tell if she and Ecco are incubating because they cover the eggs to keep them from freezing and it’s certainly been cold lately. The only way we’d know if they were truly incubating is if we could see whether their brood patches (bare skin) were touching the egg. I made that call about “not incubating” based on Carla’s 90 minutes off eggs this morning from 5:00am to 6:30am. It’s a dangerous move if she had already started incubation. However, there is variation in behavior that is not fatal to the eggs so I will reflect that in the post.
Pitt, COL, A fourth egg got laid this morning at basically 10:25:15 am. Just an FYI if you’d like to know and/or update info.
Thank you, Laurie! I was wondering when/if that would happen.