This summer you may have wondered why you are seeing so few insects squished on your car’s windscreen, compared to a road trip several years ago.

This is because insects are declining globally at an alarming rate.

One extensive citizen science survey looked at insects numbers over several years by looking at insect deaths on car number plates. They asked people to clean their number plates before a journey and then photograph it afterwards, and count the number of bugs killed.

The survey was conducted from 2021 to 2025. It found the number of flying insects sampled on vehicle number plates across the UK had fallen by 60% in five years. Analysis of records from more than 25,000 journeys showed an annual average decline in bug splats of 19% since the survey began in 2021.

Some people may look at these statistics and wonder why they should care. But the decline of insect life is a significant cause for concern. It’s also not just in the UK where we are seeing declines, but also across Europe and in our tropical rainforests, including some of the most biodiverse spots on the planet. Agricultural land is seeing some of the worst effects.

There’s an estimated 10 quintillion (10,000,000,000,000,000,000) insects alive on this planet, over a million described species, and estimates of millions more yet to be discovered. But we are losing insects far faster than other animals, and at an unprecedented rate.

A review in 2019 suggested 40% of insect species are thought to be threatened with extinction. Ants, bees and wasps (Hymenoptera) the butterflies and moths (Lepidoptera) and dung beetles are thought to be the most affected. More recent reviews show similar declining trends on a global scale.

Why are insects disappearing?

The reasons for losing our insects range from habitat loss, disease pollution and pesticides. Agriculture is a major concern as land is turned over to farming as it may remove existing habitats – essentially removing some insects homes – but agrichemicals such as pesticides, designed to kill agricultural pest outbreaks, are also negatively affecting those non target insects that we want.

Climate change is as a major concern, and one that potentially exacerbates other factors. When it’s hotter water availability becomes harder, plants become more stressed and food availability becomes tricky for insects. In the same way that humans struggle in the heat, this is the same case for other animals. Insects can try to cope with extremes in temperature by using water to cool, fanning their wings or simply going somewhere where it is less warm.

The summer of 2026 saw record temperatures and is expected to be the hottest year on record for the UK. Coupled with intense droughts, wildfires and a changing landscape, this is a tricky world for insects to navigate.

This changing climate is affecting whole communities of insects, where they live and what they do.

With places like the UK seeing a shift from its typical cooler climate to a more Mediterranean one, we are seeing species move from southern Europe to northern Europe. We also see insects changing their seasonal life-cycles, with effects on other species that are dependent upon them. They are even carrying diseases to new populations of humans or animals as climates become more amenable to certain species that may carry diseases or other pathogens .

This loss of biodiversity is often referred to as the sixth mass extinction, or the sixth time in history that we know of that we have lost such a vast number of species in rapid succession.

Why should we care?

Insects have evolved in large numbers because of the extent of what they do in the natural world.

They keep pests under control, they pollinate our plants by transporting pollen from one flower to another, recycle our waste by feeding on and shredding material and generally keep our planet in a good state.

American naturalist E.O Wilson said: “If insects were to vanish, the environment would collapse into chaos.”

However, insect populations can recover. Appreciating how fundamental they are is the first step in conserving and restoring what we are losing.

Alex Dittrich does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

You may be spotting bodies of dead bumblebees lying across pavements near you in the summer months.

There are several reasons for this, some to do with the weather and some very much due to humans.

Bumblebees are social, living in colonies that are maintained by very active workers with a relatively short lifespan of 4-6 weeks. This means, that in a relatively short space of time, older bees die off and to prevent disease making it’s way through the colony, the healthy young workers bring out their dead, moving them far away from their colony.

Another factor is the weather. It was the warmest June on record in England (and the second hottest for the whole UK) in 2026 and other high temperatures are expected this summer.

Thermal stress in bees is caused by this kind of extreme heat. Prolonged heat exposure alters development and threatens long-term population stability.

Heatwaves also severely disrupt reproduction, flight capacity and ability to forage. Social insects including bees rely on cooling behaviour for example fanning their wings when things get too hot to buffer the hive but there are limits as to how effective this is in extreme heat.

As it gets hotter bee foraging activity may increase, and they may cover greater distances. Bees can thermoregulate themselves by moving heat around their body while in flight, but extremes of temperature can affect their health.

Don’t kill your dandelions

Other elements play a part in bee deaths. Pesticide and herbicide use is commonplace and these chemicals affect the fitness of bees, causing them to die off. However, not only do these chemicals affect the bees directly, they can also remove important plants that they rely on for food causing them to starve. Dandelions for example, are a massively important nectar source for bees, but also a plant commonly controlled with herbicides. So don’t weed your garden and pull them out.

Pesticide use is one of the historical key causes for loss of bees. Pesticides applied to reduce the insects feeding on crops – is some what ironically – responsible for harming a group of animals responsible for their pollination.

The EU and the UK have banned the use of the most harmful neonictinoids, however pesticides are still routinely used, with harmful knock-on effects on pollinators. Insecticides such as organophosphates, synthetic pyrethroids and phenylpyrazoles cause paralysis and death of these insects, as well as disrupting the bees ability to navigate.

Habitat loss is another key issue for bees, with land use changing for housing developments, intensive agriculture and other human structures such as roads. Without these habitats to support the bees, their populations suffer.

Climate change is causing other problems.

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Read more: A common soil pesticide cut wild bee reproduction by 89% – here’s why scientists are worried

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Phenological mismatch is when two organisms that are dependent upon each other appear at the wrong time. With a changing climate this is happening. An example of this is that plants that the bees are dependent upon being in flower when the bees aren’t around. Essentially they are flowering at a time of year when the bees aren’t there. They could come out of hibernation too early and not have any nectar to feed on, or conversely the flowers could come out before the bees appear. This, of course, is a disaster for both flower and the bees.

Bees under threat

Insects are the most diverse and abundant group of animals on the planet, but in spite of this dominance they are the most threatened.

We are losing our bees at an alarming rate. In Europe, the number of wild bee species considered at risk of extinction has more than doubled from 77 in 2014 to at least 172 today (around 10% of assessed species).

But we really need them. They provide so much support for our planet, as decomposers, pest controllers, food for other animals and generally for keeping our systems clean and tidy. Scientists call these these roles ecosystem services. However, one such service they provide is directly very important for us, and disproportionately carried out by one group of insects, the bees, and that is pollination of our crops.

Bees are one of the most diverse insect groups. They support an estimated 75% of global crop pollination, and nearly 90% of all flowering plants. The rest can be pollinated by other animals, or by the wind and weather.

If we lose that food security afforded by our pollinators we could have a global food crisis on our hands.

Anything that can be done?

When it comes to pesticide use, be a thoughtful and informed consumer. Support local, sustainably produced food where possible and, if feasible, buy from farmers who use nature-friendly practices. This does not necessarily mean choosing organic products, but rather considering how food is produced and the environmental impact of different farming systems. As a homeowner, explore non-chemical alternatives first, and apply any treatments sparingly and responsibly to minimise harm to beneficial insects and other wildlife.

One of the simplest ways to address habitat loss for bees is to make room for native species. Plant a diverse range of native flowering species, and leave some areas of lawn unmown. This can help create safe havens for bees.

In the short term there is one thing that people can do to help bees in distress. Providing sugary water to a bee you see struggling on the pavement on a hot summer’s day can help revive it. A mixture of sugar and water will do the trick at a two-to-one ratio of sugar to water..

Moving the bee, if safe to do so, to a flower or a shady spot too is also advised. But please do not do this if you have allergies, or are likely to get stung.

Alex Dittrich does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.