Excuse the dodgy quality, please. My telephoto lens is manually focused and it is a pain trying to follow these hummingbirds and work the lens at the same time. I've settled on focusing on a single group of flowers then clicking like a maniac when a bird visits it. Sometimes it works, and the clearest examples are attached.
After browsing Wikipedia and National Audobon archives I gave up. One site said broad-bills don't come this far north (Pueblo, Colorado) and another suggested it might be a Costa's. So here I am.
Some details the photos don't give very well: both the birds I've seen are drab colored and both appear brown (despite one of the pictures seeming green) leading me to believe they're female. They don't appear to be too terribly aggressive. Both will be working the shrubbery at the same time without any apparent problems. Although a third one showed up today and I'll describe the scene later if anyone's interested. I haven't heard any vocalizations from them, either. One is rather adventurous: when my two coworkers and I were seated at a table in the garage, she came up and hovered in front of us within easy arm's reach for about ten seconds or so as she sized us up. (And naturally she did that when I had my long distance lens, not my wide angle. Thanks so much, bird.)
The very last picture was a lucky shot. You'll have to zoom in at the center then pan up and left to see her. It's the best one I've got showing details of plumage, body shape, and bill.
Any help you can offer is gratefully accepted and I tip my hat to you in advance.
And special acknowledgement to those of you who photograph birds professionally. Over the last month, I've gained quite an appreciation for what you go through. I'm so glad I'm doing this digitally and not burning up film with all the bad shots!