Tierra de Oro Laboratory

Physiology and Ecology in the Pinyon-Juniper Savanna

Owls 2025: Incubation I (4/1/25 to 4/6/25)

4/1/25: Five Eggs

Owls with five eggs.

The pair now has five eggs. After spending many hours a day off the nest last week, the female sits on the eggs continuously with just a short break before daytime and after dark. Here’s a rare time when she left to eat a mouse after the male brought it in to her.

4/2/25: Have Your Mouse and Eat it Too

Here is another clip of the female receiving a mouse delivery and her long effort to swallow it whole.

Starting to swallow the mouse.

It took 5 1/2 minutes for her to completely swallow it, so I broke it into two separate clips that are much shorter overall. 

Finishing the mouse.

She is sitting on the eggs continuously (she didn’t even leave to eat that mouse) and took a short 4-minute break just before daybreak. 

Still 5 eggs, so it seems we won’t get a 6th egg this year (we had only 5 in 2022).

The first eggs take about 35 days to hatch, so we should expect the first owlet on April 22. 

4/6/25: Fueling Incubation

Hungry owl finally gets fed just before daybreak.

She had been sitting on the eggs continuously since her ~7 pm break and was calling for her partner to bring her something.

He finally shows up with her favorite, a kangaroo mouse (note the long tail), just before daylight. This clip shows her receiving the mouse and starting to leave with it, then deciding to eat in.

The second clip shows her, after about 3 minutes of eating, taking it out and is away for about 20 minutes.