Who can help explain this mystery?

A few weeks ago we noticed about a dozen small tan-colored swirls on our screened-in porch. Upon closer inspection it became clear that each swirl was made up of dozens or even hundreds of little eggs.

We were mystified as to what might be laying these eggs.  And then the other night, Adrian spotted a moth doing a little back-and-forth dance on another screen. I didn’t get a picture of the moth, but I got a picture of what it left behind:

Anyone know what kind of moth this was or have any insight into this kind of behavior? I’ve never seen it before.