- Early and frequent mowing is a threat to grassland arthropods. To date, measures to counteract these losses have largely been limited to extensification concepts, which are not always feasible on intensive grasslands.
- One option for insect-friendly mowing is the use of chasing devices, which are designed to chase away arthropods before mowing. Scientific research on their effectiveness is limited to one study on parasitic microhymenoptera. Studies on other groups are lacking.
- In a 3-year experiment, we have investigated the effectiveness of three devices, that is, two mechanical flushing bars (truck tarpaulin, hanging down metal brackets) and a blowing device. We tested different driving speeds and distances of the flushing bar from the mower on seven abundant arthropod groups that differ in their escape strategies.
- We found the blowing device to be the most effective. At the maximum driving speed of 12 km/h, it had an effect on almost all taxonomic groups studied except Araneae and Hymenoptera. At this speed, the metal bracket flushing bar was only effective on Diptera and Coleoptera. The truck tarpaulin flushing bar was only effective at a low driving speed of 5 km/h, albeit on four out of seven taxa.
- Chasing devices have a great potential to deter arthropods prior to mowing, thereby reducing mortality. Whilst a blowing device works at higher speed, mechanical flushing bars have a limited effectiveness (metal brackets) or only work at low speed (truck tarpaulin).
Frank, J., Erhardt, S., Betz, O., M. Steidle, J. L., Böttinger, S., & Sann, M. Minimising insect mortality during grassland mowing: The potential of insect chasing devices. Insect Conservation and Diversity. https://doi.org/10.1111/icad.12854
