Waxing moon and mother and Child A mother Common Potoo shares a broken off branch with her fledgling as a waning moon looks over them. Potoos are nocturnal, and during the day they remain perfectly still, and use broken off branches for camouflage. The mother lays only one egg, at the end of a broken off trunk like the one in the picture. By sheer luck a Common Potoo raised its young very close to my home. I was able to watch it grow from a tiny nestling to a robust fledgling. One lucky day I went to photograph it and the waning moon was perfectly in place.