Yup!!! I love when they 'swoop' down towards the ground while emitting vocalizations...pretty sure it's a mating behaviour.
That's actually one of the few things I'm gonna' miss when we leave California, the hummingbirds. Washington is a little too cold for the little suckers I guess, as I didn't see my first one until I moved here 30 years ago. I don't remember seeing any of them when I was a kid up north.
Believe it or not, quick as they are, one of our cats is fast (and sly) enough to catch 'em. Usually he brings 'em inside for my wife to 'rescue'. It's amazing to see her coax the bird from the cat and then set it free outside...remarkably, most of 'em make it.