Hatch Watch at Xcel Fort St. Vrain!
On hatch watch at Xcel Fort St. Vrain! Listen for an eaglet talking through its shell! https://youtu.be/LeMC541Cn1E
So what happens right before hatch? The rapidly growing embryo is taking up nearly all the space in the egg. It has turned so that its head is at the large end of the egg next to the air space, pierced the internal membrane, and is breathing air with its lungs. It is taking the yolk sac into its body through its abdomen as it consumes most of the remaining albumen and yolk. When it is done, its abdomen will seal shut, leaving a yolk sac scar.
In altricial birds like bald eagles, “egg talking” begins imprinting young on parents before young hatch. Since eaglets can’t see well at and just after hatch, vocalization is an important part of strengthening the bonds between parents and young.