When I first walked out onto my patio a few minutes before I took these shots, I noticed two whirling balls of wings on the ground. It took me a couple of moments to realize it was my 'regular' female Annas tusseling with another hummingbird. After the dust settled, she perched on a bush limb to be on the lookout for a return of the intruder. I wish I'd had my camera to capture the 'cat fight'. I've seen hummers chase others away but I had never seen a down right brawl like that.
Here she is guarding "her" feeder after the fight.