Warbling Vireo

I spent about 45 minutes this morning before church at Mentor Graphics. I got to experience a very annoyed Great Blue Heron shriek at a Red-wing Blackbird as it flew across the pond. Evidently the Blackbird was not happy with the Heron and was diving at it.
The first bird I encountered was what I think is a Warbling Vireo. Another new bird for me. I only found two candidates for it from my field guide; either a Warbling Vireo or a Tennessee Warbler. A Warbling Vireo seemed to be the better fit. It stayed pretty high in a couple trees as I followed it around. Most of the pictures were a little too blurry once I zoomed in on the bird within the image. These two images were the most in focus out of the bunch.
I'm noticing a change in the types of birds I have been seeing. Most of the ducks have migrated north and more and more song birds are arriving. The ducks were a lot of fun and I miss them, but I'm hoping to see some new interesting birds. Also, it is getting more difficult to get clear shots of the birds in the trees and shrubs as their leaves bud and grow.