So as I was leaving the park yesterday I saw a bird fly into a tree near the ladies pavillion. It wasn't a starling, or a grackle, or a robin so I gave it a look. It was about starling-sized. I didn't get a close view, but I did get a few pictures. It looked grey (with brownish undertones, not blueish undertones) with a white bottom face and a greyish top face. I only saw the tail from the back and sides, I never saw the underside of the tail.
The bird looked like it was hunched over, like a fairly bulky man in a trench coat trying to not be noticed by the police.
And that looks like an eye ring..... Yep, my best ID right now is yellow-billed cuckoo. I wish I had figured out a way to get a closer look and better pictures! Lesson for myself - your eyes are getting better at figuring out if they are seeing something unusual - trust them, and when they tell you to pay attention, do it! :-)