This bird is a whiz at catching dragonflies and moths. Seems to like mostly low-story bushes. We think it's either an Eastern Phoebe or an Eastern Wood-Pewee based on the "vest." It also does move is tail up and down when sitting on a branch, like a Phoebe, but the vest looks more like the Wood Pewee based on the Cornell photos. Haven't been able to separate its calls from others' in the same area. Thanks for any help!
CLOSED: Fly-catching bird around marsh in New England
Eastern Phoebe - note the strong contrast between the dark cheeks and white throat; in Eastern Wood Pewee, the head is much more uniform. The fairly inconspicuous wingbars also support Eastern Phoebe (more obvious in EWP).
Thanks, Resin. That seems to be the consensus among my birding Facebook friends, too.