Strange objects in the tree

It was a beautiful morning and I decided to get a photo of the trees against the bright blue sky, but couldn't understand what the objects at the top of the tree were.  I changed to the long lens to take the shot and it turned out only to be some Pigeons and Magpies basking in the warmth of the sun after what must have been a cold night as the car needed to be defrosted before being driven.