Birdwatching at the Charles River

Work has finally slowed down enough for me to take my walk at lunch again. Today was a little overcast, and much cooler than it has been, but it was good to get some fresh air.

I walk along the Charles River and have a 45-minute loop that I do. Now that I'm actively looking for birds, I've learned where to spot certain ones. The path at the beginning of my walk cuts down close to the river and I've decided that's my best bet for seeing interesting birds. It's overgrown and there are plenty of places for them to hide. On the first part of my walk I saw several titmice, a flicker, chickadees and house sparrows. Later in the walk I saw what I believe was a pair of warblers. I've seen this bird before on my walks along the river, and it's the first that I've tried identifying. This was the best picture I could get today, and although it's hard to tell, it has yellow markings on the crown and black and white feathers on the wings. I'll do a little more research to try and figure out exactly what kind it is, but I'm welcome to suggestions too.

I have an excellent little bird guide from 1909, written by Charles Reed of Worcester, MA. The title is Land Birds Bird Guide Song and Insectivorous Birds East of the Rockies. There are pages and pages of warblers in there and I think that's my best bet.