2010 - Kinderchicklets / Why do they roll the eggs over?

[Kinderchick]

Very interesting idea that you posted for the Kinderchicklets, regarding the rolling of the eggs, Tracy.  This morning all the 'chicklets took turns pretending they were Princess or Ivy rolling an egg over. I crumpled up a piece of paper, as you suggested and each of the 'chicklets took turns squatting down and rolling the paper "egg" over with their knuckles, as gently as could be. Some of the Kinderchicklets (and even their teacher) found it a bit difficult to squat down and roll the "egg" at the same time!  So we concluded that it would probably be much easier to do, if we were all Peregrine Falcons!

[The Peregrine Chick]

Hey Kinderchicklets!

Sorry it has taken me a couple of days to answer your question, it has been very busy since the chicks started hatching. 

So why do the peregrines roll their eggs and aren't the adults afraid of breaking the eggs. 

First the rolling ... the adults roll the eggs so that they can make sure that the eggs stay warm all the way around.  They need to stay warm all the way around to help the chicks develop inside the eggs.  If they get cool, it takes longer for them to develop and hatch.  If they freeze, it will kill the chicks.  So they roll the eggs to keep them the same temperature all the way around.  For those of you with microwave ovens at home, watch when your mom or dad uses it next time - some of them warm the food by turning them around and around and around so that the food heats evenly for you to eat!

Second, breaking the eggs ... no, the adults are worried about breaking their eggs.  When they move them them roll them around by putting their feet underneath the eggs and roll them that way.  The best way to show you would be for you to take a small ball or block or crumpled up piece of paper and put them on your knuckles (your teacher can show you what I mean) ... now try to roll them around with just your knuckles.  Its not easy to do but it also means that you can't crush them with your fingers.  When they "lie down" on the eggs to incubate them, they are putting them under their feathers next to their skin to use the heat from their bodies to keep them warm.  And again, because the eggs are close to their skin, they know not to lie on them too hard.  And the birds don't weigh very much - Ivy weighs about 800gr (about 1.5lbs), Princess weighs about 1500gr (3lbs) - so not very much at all.

Let me know who can roll their "eggs" on their knuckles best!!

[Kinderchick]

For a few weeks before the Kinderchicklets began watching Princess & Ivy on the webcam here in Winnipeg, they were watching Mother Goose and her eggs on a webcam in Edmonton. They noticed that Mother Goose often rolled her eggs over with her bill. Now they are beginning to notice that Princess and/or Ivy seem to do the same thing to their eggs, with their beaks. So today's question from the 'chicklets is this: "Why DO they roll their eggs over, anyway, Tracy? And aren't they afraid the eggs will break?"