We stayed the night and the next day the eagle came back with three friends, there was one in the original perch in the tree and three circling overhead, riding thermals and relaxing. Eventually one of them joined the birdy in the tree and I decided to see if the ancient Nikon could take a photo through the eyepiece of the telescope. The Nikon died when I threw it against the floor of the Boston ICA by mistake two Octobers ago, but then suddenly started working again last year and I've been using it a lot lately.
This is the shot where you pretty much would never see an eagle on top of the left most tree unless someone pointed it out:

Zooming as far as the Nikon will go does nothing:

So hey! Take a picture of the telescope!

( And then it kind of works out... )