The population of flying insects in the United Kingdom has fallen by two thirds (63%) in just three years, according to new findings from a nationwide “Bugs Matter” citizen survey, raising alarm among ecologists and conservation groups over the accelerating decline of insect life in Europe.

The Bugs Matter survey, coordinated by conservation charity Buglife and the Kent Wildlife Trust, collected data from thousands of participants across the UK between 2021 and 2024. Volunteers recorded the number of insect splats on their vehicle number plates following journeys that are used as a proxy to measure the size of insect communities.

Dr Lawrence Ball of Kent Wildlife Trust said in the report: “This huge decrease in insect splats over such a short time is really alarming. Its most likely that we are seeing the compounding effects of both a background rate of decline as well as a short-term cycle of decline, perhaps linked to the extreme climate in the UK in recent years.”

Bug splats declined 8% from 2023 to 2024, following sharper drops of 44% in 2023 and 28% in 2022. This shows the rate of decline has slowed and it may even flatten or reverse next year, Ball said.

But the results have alarmed scientists as the trend remains unclear and drop in splat counts over the three-year period is unprecedented, corresponding widespread collapse in flying insect numbers. Buglife described the findings as “a terrifying phenomenon that should be spoken about much more.”

“This is a wake-up call,” said Matt Shardlow, chief executive of Buglife, in a statement accompanying the data. “Flying insects play an essential role in pollination, food production and ecosystems. Their decline signals a broader environmental crisis.”

Other studies have found the problem is not limited to insects: the earthworm population in British soils is also collapsing with equally dire consequences for agriculture.

A comprehensive analysis of over 100 studies spanning nearly a century indicates that earthworm abundance has decreased by approximately 1.6% to 2.1% annually, amounting to a 33% to 41% decline over the past 25 years .​

Earthworms also play a crucial role in maintaining soil health, facilitating nutrient cycling, improving soil structure, and enhancing water infiltration. Their activities support plant growth from beneath as well as providing food for various bird species.

Several factors contribute to this decline, including intensive farming practices, pesticide use, and habitat loss. For instance, conventional tillage disrupts earthworm habitats, leading to population decreases. Additionally, climate change and pollution further exacerbate the problem.​

The disappearance of both worms and insects threatens to have a cascading effect on ecosystems and agriculture.​

Efforts are being made to address this issue. The Soil Association in the UK has initiated citizen science projects encouraging the public to participate in earthworm surveys to monitor soil health and raise awareness.

The results of the Bugs Matter survey have been backed up by anecdotal evidence and appears to be a Europe-wide phenomena. Political commentator Arnaud Bertrand noted: “When I was a kid over 30 years ago, during even short journeys in the French countryside our car's windshield would be absolutely littered with insect splats. Last year, I drove from Paris to the South of France and my windshield was pristine when I arrived: not a single insect.”

The so-called “windscreen phenomenon” is increasingly cited by scientists as informal evidence of insect decline across Europe and North America. Academic studies have supported these observations, linking insect loss to habitat destruction, pesticide use, climate change and pollution.

Insects are an essential part of the ecosystem, in particular they play a crucial role in pollinating plants, which would die without the help of insects. They are also important to nutrient cycling and serving as food for birds and other wildlife. The collapse of the insect population has prompted warnings of cascading effects on biodiversity and food security.

Buglife and partner organisations are calling for urgent action from policymakers to address the drivers of insect decline, including stronger protections for habitats and reductions in pesticide use.