You rarely see two male adult carpenter bees in the same photo.
They are very aggressive and territorial. While they're waiting for females to arrive, they chase all prospective suitors away.
Unlike the females, however, they can't sting.
I was watching a male carpenter bee ((Xylocopa tabaniformis) nectaring sage when I heard a loud buzz. From out of nowhere, a ferocious-sounding male carpenter was heading straight toward the unsuspecting male like a bat out of the proverbial you-know-what.
In a flash, they were gone. Battle over.
Until the next time.