These two birds (same one on top and bottom left) were part of a minuscule flock of three at the top of a birch in London ON.
The left bird has much finer streaking, just a few streaks on the undertail, and lighter lores. I realize that there is a lot of overlap in Hoary and Common types, but I'm hoping someone may provide some more definitive opinions than my own.
Thanks in advance
stuart