mary Bolton wrote:Yes like fitting the metal tub within the clay pot. Also is the rain guard they sell the same thing as a bird guard.
If a sparrow can fit through the hole... it will. Your fist is bigger than a sparrow BTW. (Mine is like a few of them

) You could put hardware cloth around the inside, I would guess. For the size of hole a bird can fit through, look up birdhouse making. It seems when I made one in my childhood, we used a one inch hole.
If you do not use a CO (
Carbon Monoxide) detector, I would suggest one for any home with flame heaters, gas or
wood, with any kind of chimney. But that is just me.