These are tree swallows, as for air speed, I have no idea.
All I can say is, they're quick.
It's much easier to catch them taking off or landing than it is to get them in flight.
It can be done, but it's tough.
Whoa...do you ever think of selling these, or, put together a book of your own? Of course, each of your 1,000's of images is like a child of yours and so...who do you love most>....lol Traveller
