At 105F, it was so hot that even non-swimmers were taking a dip.
Wasps normally anchor to the edge, stretching to the water to drink. This guy must have been parched. He did a belly flop more than once, floating for a moment, then taking off to circle and flop again. It's an interesting innovation, and a risky one. I don't know if he'll have long-term success. But that's never known early in an evolution.
He might stay a mili-second too long, feet sinking below surface tension, and find himself unable to take flight. Or he might be one of the wasps the female summer tanager snagged later in the day to feed her young.
I'm hoping to see him again. Innovation is good. And there are plenty of edge-hangers for the summer tanager.