Eastern Wood-Pewee. The chickadees have come out of their secretive breeding season mode and now are back to chattering throughout the park. In addition to attracting the attention of birders, their voices also attract other birds, especially spring and fall migrants. Since breeding season it done, I've gone back to spishing when I find chickadees to see who else pops up. Here it wasn't a migrant, but a summer resident pewee.
Eastern Wood-Pewee. Notice how the top bill has a small hook on the end.