Knocked one out of the air earlier the same day and was shocked to see massive red three-cornered "airbags" had emerged from the corners of the pronotum and abdomen. I didn't have my camera with me, but later that day I caught another, and was able to make it "poof" by poking it (although it wasn't as "poofy" as the previous one - and it deflated within seconds after being poked).
Apparently this is something this group of beetles does: https://en.wikipedia.org/wiki/Malachiinae
"Malachiinae have peculiar orange structures along the sides of the abdomen, which may be everted and saclike or withdrawn into the body and inconspicuous."
Collecting material from the cedar fence
Double-crested Cormorants with American White Pelicans
They're back! Was hanging out with a bunch of Chipping Sparrows (entered in a separate observation)
One large flock and a smaller one behind (edge of it is visible in the upper right of the last image)
Male, one of three actively singing for a mate.
sorry its so quiet; a flock flew over me...