I know very little about bats; they are, after all, very difficult to identify on the wing, and I'm not inclined to catch them in nets just to satisfy my own curiosity. I enjoy seeing them, though, and feel privileged whenever they hang out at my place during the summer.
Their favourite spot is outside our kitchen, in a bat-sized gap behind one of the wooden beams supporting a short section of roof over the terrace. There's often one, occasionally two, sometimes none, but recently there were four. It was the record-breaking number of droppings on the patio that made me look more closely.
I've gleaned that it's not unusual in some species for small bachelor groups to share temporary summer roosts. Three of my four were dark brown, but one was much lighter - almost gingery. I've seen him before (or one just like him). Perhaps he'd invited his mates for a sleepover.
From their droppings, and close comparison of photos with internet images and descriptions, I'm pretty sure they are common pipistrelles. There are other species around, though. I sometimes find a few much larger droppings on the outside sill of our garage window, but there's nowhere to roost above that, so it must simply be a stop-off point during the night. There are biggish droppings in our pool-house too. I can't work out how any even get in there, never mind where they might spend the day - but I suppose they only need the tiniest of cracks to squeeze through. I do see bigger bats flying from time to time as well, and would love to know what they are.
At dusk the other evening, I opened the kitchen door to watch the welcome rain, and saw one flying every which way, at eye-level, a few feet beyond the terrace. Feeling it must be one of "mine" and had probably just left the roost, I stood in the doorway, mesmerised. Then it flew to within an inch or two of the roosting beam, touched the wall, and took off again. More tight loops in the rain - back to the wall - touch - away. Loops - back - touch - away. On the fourth or fifth return, it landed on the wall again, and this time quickly crawled up behind the beam. I know for sure that it didn't come back out, and less than a minute later, another bat did exactly the same thing - making several split-second visits to touch the wall before finally landing flat against it and crawling into the roost. After a few more seconds, a third followed suit, once again only joining his friends after several approaches. I waited to see if any would re-emerge, but they stayed put - clearly unappreciative of the rain.
I wonder if this is typical behaviour when returning to a roost, and what the purpose is behind those repeated circuits and bumps. Is it some kind of check, to make sure they're in the right place and/or that it's safe?
Here's a short clip of the boys trying to get a good day's sleep. With apologies for the quality - I had to handhold the camera and it couldn't always decide what to focus on.
I have to include this clip as well. It's even shorter and rather sweet. Well, up to a point. Seems I have a knack for catching them at the wrong moment.