Around this time of year, we normally have three bats flying around our garden in the evening. Earlier in the year, there are two. I always take three bats as a sign of another successful year's breeding.
Tonight, however, there were at least five bats wheeling around the back garden. As ever, they flew remarkably close to me. I didn't bother to get my bat-detector out. I've come to the conclusion that the bat-detector destroys much of the magic of bats. I love the way they suddenly appear out of the gloaming, and flit silently around my head. The bat-detector might help me to enter the bats' world, but it also means I lose the magical silence.
But tonight it wasn't quite silent. I don't know whether it's because of my current head-cold, which is certainly affecting my hearing, but suddenly I realised that I could hear the bats' clicks as they flew towards me (but not as they flew away). The clicks were only just audible, but they were certainly there. Perhaps they've always been there, but I haven't noticed them before. It will be interesting to find out if I can still hear them once this cold has gone. But perhaps, as I suspect is the case, the bat-detector has given me a better idea about what to listen for: the frequency of the clicks (as opposed to the frequency of the sound carrying the clicks), and the fact that they are loudest as the bat travels towards you. So, not a complete waste of money, then!