Flying Insects Have Declined by 60 Percent in the U.K., Survey Finds

A rare Adonis blue butterfly in England's Yoesden nature preserve.

A rare Adonis blue butterfly in England's Yoesden nature preserve. Charles J. Sharp via Wikipedia

A new survey of flying insects in Britain found their numbers have dropped nearly 60 percent since 2004, a “terrifying” decline given the vital role that insects play in pollinating crops, consuming organic waste, and killing pests, advocates say.

For the study, the Kent Wildlife Trust and Buglife, two U.K.-based conservation groups, compared the number of dead insects on license plates in 2004 and 2021. Data was collected by members of the British public, who recorded where they drove and how many squashed bugs they found on their cars using a smartphone app. The insects declined most in England and Wales, with drops of 65 percent and 55 percent, respectively. In Scotland, where there is more wild land and fewer cities and farms, bugs declined by just 28 percent.

It’s possible that 2004 was an especially good year for insects and 2021 an especially bad one, which is why, advocates say, it’s important to collect data annually to better gauge long-term trends. However, the findings are consistent with other research showing an alarming decline in insects. A 2019 study found that the global mass of insects is shrinking by 2.5 percent a year and that insects are going extinct eight times faster than reptiles, birds, or mammals.

“These declines are happening at an alarming rate, and without concerted action to address them we face a stark future,” Paul Hadaway, director of conservation at Kent Wildlife Trust, said in a statement. “We need action for all our wildlife now by creating more and bigger areas of habitats, providing corridors through the landscape for wildlife and allowing nature space to recover.”


How Non-Native Plants Are Contributing to a Global Insect Decline