Dad, peeking out the front door. (Taken June 15th in Warren Co., NJ).
At least some of the baby tree swallows in my box (concieved during this copulation event) were still in the nest yesterday (July 4th). I could hear them chirping in there, sounding pretty much like the adults. I think I saw a fledgling or two (looked like drabber versions of adult) but didn't have a chance to confirm it. Anyway they are pretty much home free and should be fledging soon. (Nestling periods lasting longer than 14 days have to be pretty rare. I know Acadian flycatchers usually go about that long, and that they are on the long side among songbirds.) So that would be about one full month from copulation (May 30th), through hatching (June 19th), to fledging (about July 4th). A bit longer if you count nest building which I didn't actually observe (I must have been away during it).