
So, the timeline:
This spring, a mother raccoon had a litter of three babies, in the walls of our house. We had Bay State Pest Control trap them out, once the babies were old enough to leave on their own -- we DIDN'T want to trap the mother, then leave babies to die of starvation in our walls. Not only is that cruel, but we just don't want rotting carcases.
Over the next couple weeks, into the early summer, we trapped out all three juveniles. We never trapped the mother, but, since we'd left a baited trap there for a week, and nobody took the bait, we figured that the mother had left on her own, once the young'ns were gone. Anyway, we weren't hearing any noise from the walls.
So they blocked up the holes where the raccoon had been getting in and out.
That night, and the next night, Lis said that she thought that she'd heard someone trying to get back in, and sent me outside with a flashlight to see if a raccoon was bashing on the exclusion to try to break back in. And I didn't see anyone.
She must have been hearing the raccoon bashing on the INSIDE of the exclusion, trying to break OUT. And, around two in the morning, the raccoon found a hole that went to the INSIDE of the upstairs apartment, and our upstairs tenant saw it.
One other piece of data: at one point, when the raccoon was hunkered in the china closet, we turned out the lights to try to make it unpanicked enough to make a run for the porch. One of the police officers turned his flashlight on the raccoon, and then away. And I saw a glowing spot on the raccoon's ear. There was a glow-in-the-dark tag on it.
So, somebody had tagged the raccoon. Which means that it had been previously trapped, tagged, and released. Which is why we couldn't trap it -- you can only trap a raccoon once. If you release a raccoon, it will then understand traps, and never be caught again.
We expect, and hope, that this particular raccoon is terrified enough that she's NEVER coming back to our house. And, in any case, nobody can get in through the former holes which are blocked up.