I was listening to one of those Radio 4 amazing facts programmes a few years ago. You know the sort, where a panel of experts give answers to questions sent in by listeners on topics pertaining to the natural world, the sciences, mathematical problems and so on. On this day one particular question stuck in my mind. A listener had written in asking how, when it’s raining, insects, being close in size to raindrops, don’t seem to get hit? After some exploration of different theories, the panel came to the conclusion that rain, as it falls, creates enough turbulence around each droplet to blow any insects out of their path. Upon hearing this, the world seemed to come alive for me and I had this vision of the air around us filled with minute curlicues of turbulence caused by a multitude of falling droplets; a beautiful web of three-dimensional and invisible arabesques. I was delighted.
A few years later, while filming in some woods nearby I chanced on a lepidopterist out searching for butterflies. We fell into conversation and he told me that, for him, the day had not been so good. He’d hoped to photograph some of the rarer species but most of the ones he’d found had wings quite badly damaged by the rain. I remembered my programme and felt a little disappointed, but then, I reasoned, maybe butterflies, because of the size of their wings, created enough drag to prevent them being blown out of the way, and so they might be an exception to the rule.
So, today I’m hiding from the rain under one of the umbrellas at the café when all of a sudden, this shape appears with a splat on the stretched canvas cover. It’s clearly visible through the wet fabric as having six legs. Peeking out from the rim of my shelter I can see it’s a bee that’s been brought down with a bump by a raindrop. Unsurprisingly, it looks stunned. Since the rain is now easing I try a bit of rescue work, breathing and blowing on the bee to dry it out and try to warm it up a bit. To my surprise, this actually works. Acting a bit like a human hair dryer to warm it, and having blown off the surplus water, after a while the bee starts to buzz a bit, dislodging some more water. Then it does what any sensible insect would do under the circumstances, crawling across the surface to the edge, over the rim and then under the canopy where it clings on, probably trying to recover its senses.
Ok, its only one bee. Maybe there are instances where insects are blown out of the way by turbulence caused by falling rain, but from what I can see from the behaviour of this one individual, it seems likely that what actually happens to insects during rain showers is pretty much the same as anyone else caught in a shower, namely, dive for cover and wait it out. And that’s why you don’t see many insects in the rain: they aren’t stupid (well, for a given value of stupid since they can’t have very big brains) and are all hiding underneath leaves on trees and so on.
Only now I have a new problem: the afternoon is drawing on and the people at the café are beginning to put away the tables, chairs and umbrellas away for the night, one of which has a stunned bee under it. I feel a bit of a twit going over to talk to Michel to ask him to watch out for the bee so it doesn’t get trapped as he closes the parasol, but you see, I’ve helped it, so now it’s my responsibility, and I have no idea where it’s hive is.