Little Bird__

Little Bird__#13 from my Colorado sketchbook....auction soon!

I don't know my birds...there are SO many, and I have never taken the time to learn them all...I LOVE birds though, and I am saving bird-watching for old age, when I think I will have more time to study them...if something happens and I do not make it to "old age", I think I will be "OK" with having relied on my friends to identify the unknown birds for me!

So, friends, what kind of bird is this?

I sketched it near our place in southern Colorado (the San Juan Mountains)...it is light gray, black, white and a little bit of tan. There are a lot of swallows (?) in the area....the ones that build their nests out of mud in the corners of the eaves of the house...is this one of those swallows?
Its song sounds like this: TWEET or tweet, depending how far away it is...