Black-chinned Hummingbird, Hatch-year female (1625)
I took three photos of a single Black-chinned Hummingbird this afternoon. From the images, I have decided this is a hatch-year female. Note the buffy edges to the head and rump feathers, the rounded tail feathers (on image 1622), and the rounded tips to all the primaries. This year's birds are foraging now. Image captured with multiple flash units and an artificial background.