My grandchildren found a circular mass of swarming springtails today on some concrete just outside a stable in Sedlescombe. It must have contained thousands of insects. This particular species, Ceratophysella bengtssoni, is well-known for this kind of behaviour and swarms numbering millions of individuals have sometimes been seen. No one knows quite why they do it, though it is thought to be associated with mating. Usually the swarms last only a short while and are gone by the following day.