Mystery Solved!

The dove which I photographed on the porch roof two days ago returned last evening to the same spot.

On the chance it might be there again this evening, I brought along a telephoto accessory lens for my cellphone, and this is the result.

When I got there, it was looking down at me from the roof proper. I talked to it and hooted at it, offering my hand in the air for it to land on.

I was standing down at the base of the porch, and it did indeed fly down almost to my hand, then swooped back at the last second to its vantage point of previous evenings, where it stayed.

It was only after I got home and was looking at my day's pictures that I noticed the ring on its right leg. Apparently it is someone's pet. Why it's hanging out on our porch roof every evening is beyond me. But now I know why it's so tame.