For the 4th year now, a hummingbird has set up house in the back garden. I've come to believe that he is not a Rufous, but an Allen's. The back and head are green (not a 100% accurate way to tell), the outer tail feathers are narrow and the courtship flight has a J arc. The last two characteristics are of the Allen's. He also sounds like a helicopter in flight -- high pitched, loud and mechanical sounding.
What I don't have is a high-speed camera that can catch the wing feathers outspread to observe the R2 tail feathers as either notched (Rufous) or not (Allen's).
He visits both of the feeders in the back garden a few times per day. In the past, he has stayed from early April to mid-June. This year I was delighted to be outside on March 25th in the afternoon when he arrived and drank insatiably from the feeders.
I would be happy if someone might want to come and take a look and a good photo or two. I've searched through myriad references, among them, this one for comparison with the Rufous: https://fieldguidetohummingbirds.wordpr ... vs-allens/