This afternoon on my walk I stopped to look in the tree holes where I had seen the birds going crazy yesterday, and sure enough, there was a red phase Eastern Screech-Owl sticking its head out in the mid-afternoon sun! The birds had undoubtedly seen it in there yesterday.
I went home and got my son, but when we got back there the owl ducked back into the hole and wouldn't come back out. We did see several chickadees and titmice stop by, look in the hole, and start calling excitedly before flying off. We also watched a Belted Kingfisher dive into the creek and come out with what looked like a crayfish.
On my walk, before I saw the owl, the most interesting birds were a pair of American Pipits in an open area along the hike and bike trail. Didn't see any of those on my walks last year. There's always something different out there!