Insects decline, why have they gone?
What about their ecosystem services?
Any decline in insect numbers is serious as they provide a food source for many mammals, birds, and amphibians, and they pollinate many plants including our crops.
Insects provide very important ecosystem services of pest regulation, plant pollination, and decomposition of organic matter.
Many of us have observed a reduction in insect numbers, particularly flying insects, over recent years.
Often mentioned is the splatter test on our vehicle windscreen, being not as bad as it used to be, the decrease of insect sounds at night, and fewer flying insects seen attracted by street lights.
But are the observations accurate and have they been scientifically measured?
A well-known study from Germany by Hallman et al., (2017) sampled aerial insect biomass between 1989 and 2016, in multiple sites representative of Western European low-land natural protected areas but surrounded by a human-dominated landscape.
Sampling was from the beginning of March through to the end of October each year.
