Butterfly numbers are the lowest on record in the UK.
Butterfly Conservation, which runs the Big Butterfly Count, sounded the alarm after this year’s count revealed the worst numbers since it began 14 years ago.
Many people have noticed the lack of fluttering insects in their gardens. Experts say this is due to the unusually wet conditions so far in 2024. Climate breakdown means the UK is more likely to face extremes in weather, and the natural rhythms of the seasons that insects such as butterflies are used to can no longer be relied on.
The UK had its wettest spring since 1986 and the sixth wettest on record, as an average 301.7mm (11.87in) of rain fell across March, April and May, nearly a third (32%) more than usual for the season. The Met Office has said recent decades have been warmer, wetter and sunnier than those of the 20th century.
Dr Dan Hoare, the director of conservation at Butterfly Conservation, said: “Butterflies need some warm and dry conditions to be able to fly around and mate. If the weather doesn’t allow for this there will be fewer opportunities to breed, and the lack of butterflies now is likely the knock-on effect of our very dreary spring and early summer.”
80% of butterfly species in the UK had declined since the 1970s, with habitat loss, climate breakdown and pesticide use being the main causes. Butterfly populations already hit by these issues would be less likely to be able to cope with extreme weather.
However, as well as the rain this year, butterfly species are struggling to bounce back from the 2022 drought; they do not mate in wet conditions, but they also need the plants their caterpillars eat to be adequately watered. Species including the green-veined white and the ringlet still have low populations because their caterpillars did not survive the drought. The extremes of climate breakdown mean that as butterflies try to recover from one extreme weather event such as a drought, they are hit with another event like very heavy and sustained rainfall a couple of years later.