Yverdon VD: Insect Spectacle in the Evening Sky: Reader Films Mating Ritual

In Yverdon VD, a 20-minute reader observed an unusual natural spectacle in front of his apartment. Dark stripes swirled before sunset. He concluded that this is a mosquito tornado. Here, however, it is not mosquitoes, explains biologist Daniel Cherix. The reader has seen a phenomenon that is not rare, but rare to observe.