The Summer Of Missing Butterflies; License Plate Survey Shows 78% UK Insect Decline 2004-23

Anyone with even a passing interest in the natural world will have noticed a dramatic phenomenon this year: a lack of insects. Perhaps most noticeable is the near-absence of butterflies. Species that are usually common, such as large and small whites, small tortoiseshells, gatekeepers, ringlets, peacocks and meadow browns, are in many places down to the point of having almost disappeared. This is certainly the case where I live, in Cambridge.

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Surveys going back 20 years to 2004 reveal a sharp drop in the number of insects found splattered on numberplates in the UK. The scale of decline is staggering, with evidence gathered from numberplates showing a drop of 78% between then and 2023. Such findings place this year’s sudden insect decline into the context of a longer-term trend and show how erratic weather patterns are hitting already depleted populations.

Going back further, by about a century, the drop is likely to be far larger still. Dave Goulson, one of the UK’s leading entomologists, estimates that insect populations compared with a century ago are 90% to 95% down. That was not caused by one wet spring: it is the result of a combination of factors that include the rise of ever more intensive farming, habitat loss, habitat fragmentation, pollution and the impacts of climate breakdown. Aside from the depressing silence and stillness of gardens, woods, hedgerows and grasslands, there are more practical implications. For example, many of our crop plants – including oilseed rape, tomatoes, apples and strawberries – depend on wild insects to pollinate them. Insects are also the food source of many mammals and birds that are also in decline. In the spring I also noticed the dawn chorus was much depleted, with one possible reason for that being insect scarcity.

The present position will hopefully be temporary but is nonetheless a wake-up call about the scale of losses that have taken place in recent decades. With ambitious legal targets set out in the Environment Act, including to halt species decline by 2030, and an international commitment to protect 30% of land and sea for nature by the same year, it is very clear that major change is needed now. It is pleasing to see that the incoming government has a sense of the challenge in front of us and has committed to positive measures, such as changing existing policies on emergency authorisations for neonicotinoid pesticides.

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https://www.theguardian.com/commentisfree/article/2024/jul/13/butterflies-summer-absence-british-spring-decline-insects