As well as being pollinators insects provide food for birds and other animals and help control pests. Photograph: Kevin Elsby/Alamy
Lynn Dicks at the University of East Anglia, UK, and not involved in the new research said the work was convincing. It provides important new evidence for an alarming decline that many entomologists have suspected is occurring for some time.
If total flying insect biomass is genuinely declining at this rate about 6% per year it is extremely concerning, she said. Flying insects have really important ecological functions, for which their numbers matter a lot. They pollinate flowers: flies, moths and butterflies are as important as bees for many flowering plants, including some crops. They provide food for many animals birds, bats, some mammals, fish, reptiles and amphibians. Flies, beetles and wasps are also predators and decomposers, controlling pests and cleaning up the place generally.
Another way of sampling insects car windscreens has often been anecdotally used to suggest a major decline, with people remembering many more bugs squashed on their windscreens in the past.
I think that is real, said Goulson. I drove right across France and back this summer just when youd expect your windscreen to be splattered all over and I literally never had to stop to clean the windscreen.