Well, we weren't going to be out-witted, so we took down the jar and put in its place a brick, turned on end, leaving almost no room at the top.
So much for that stroke of genius! Here are a couple snapshots of what's perched atop the brick-at-the-top-of-the-column right now:
Not wishing to offend your sensitivities, I won't show you a picture of what's at the bottom of that column - the terrible mess that they have made, once again, of our porch.
The mama bird can't even fit in the nest now - the nest being rather small, because of the miniature plot she had to build upon. She comes by, frequently, during the daytime to put food in the little-'uns' gaping mouths, but she watches over them, at night, from six feet away, perched on the eaves of our garage, across from the nest.
I'm really not a bird-hater. In fact, I'm really quite fond of them, and I'd be more than happy to have them make their abode in our fair-sized young oak tree in the front yard. But they are determined to live right here on our front porch.
So, in case you haven't been keeping score over the past two years, it's stands at: Twitterpated Birds 2, Out-smarted Humans 0. But just wait until NEXT spring. We'll show them who's boss!