When you know you are the center of attention, why not show your appreciation by taking a bow? That almost seemed like that is what this regal eagle was doing although in truth it was just stretching.
In all the time I have spent with eagles, I have never seen one stretch this way. Owls commonly do this but this was for me the first time I have seen an eagle do it. Kind of fun.
Also notice its eye. Bald Eagles (and many other birds) have an inner eyelid called a nictitating membrane. This membrane wipes front to back every few seconds, cleaning the cornea. It is translucent and the eagle can actually see through it.