Scene 1: I was observing a line of horse-tail pine trees (very like the ones on my street IRL) and my attention was drawn to two birds' nests. They were well made, with mostly pine needles outside. One was smaller, about the right size for a wood pigeon. The other was larger, and had been set in the middle of a large mat of pine needles, as often form in the forks of these trees. I thought it would be hard for nestlings to fall out because they had this kind of "verandah."
I don't remember any of the following scenes of this dream until the last one -
Scene 2: I was looking up at a tall tree and noticed a large, rough nest, big enough for a large eagle or other bird of prey and several growing eaglets (but it looked unfinished and there were no birds visible). Further up the tree was an even bigger nest, again very rough and unfinished looking - it was at least 5 feet/ 170cm across - and I was amazed at the size.
Finally I looked to a tree behind that one, and higher up again was the shell/ beginnings of a next fully 10 feet / 3metres across. I was totally awestruck and thought "Not even the biggest bird ever could make that!" But as I was looking up I saw the talons of a large but "normal" eagle poking through the spaces in the bottom of the nest structure.