Eastern Kingbirds are one of the most abundant flycatchers during migration. The neat thing about kingbirds is that they can be aged and, if an adult, sexed. The way to tell is by primaries 9 and 10. In young birds, these feathers are blunt. In adult females, these feathers have a slight notch at the tip. In adult males, like the one above, the tips of these feathers are deeply notched.
Eastern Phoebes can be identified by their lack of wingbars and eyering. They are smaller than an Olive-sided Flycatcher which might seem similar in appearance.
This flycatcher shows broad white wing bars and no distinct eye-ring. Those characteristics along with the fact that it sang its "whisper song" while flying, make this an Eastern Wood-Pewee. The Empidonax flycatchers are similar in flight.
During migration, there is always the possibility of finding an unusual bird. This Olive-sided Flycatcher was identified by the dark "vest" and by its lack of strong wingbars and eyering. This bird eventually perched and called confirming the identification.