Chickadee mating season? A different call today – high pitched, almost electronic sounding like video game rapid fire. ~3 or 4 of them chasing around among the branches.
I can’t find my Birds of Alberta book or I would tell you if it is a mating call. It often describes a bird’s song and other books don’t always. Also a description of the nest and eggs. If you have a chance you should look for it in a bookstore. They probably still sell them new.
Field to Forest 
I can’t find my Birds of Alberta book or I would tell you if it is a mating call. It often describes a bird’s song and other books don’t always. Also a description of the nest and eggs. If you have a chance you should look for it in a bookstore. They probably still sell them new.