"Back in May, I discovered a bumblebee nest in the roof of a shed after I had noticed several bees flying to and fro in front of the eaves. Normally, bumblebees fly straight in and out of a nest. So, I caught one and put it in the fridge to slow it down. It proved to be a male and I was able to deduce that all the 'swarming' bees were males when I found them visiting a nearby clump of brambles and could examine them with a close-up monocular."