Almost one in 10 of Europe’s wild bee species is at risk of extinction because of threats from the spread of farms and pesticides among other factors, a first assessment of the continent’s bee populations showed.

Bees are vital to food production but are in decline in many parts of the world. There are 1,965 wild bee species in Europe and 9.2 per cent of them are at risk of extinction while another 5.2 per cent are likely to be threatened in the near future, according to the international study, funded by the European Commission.

The International Union for Conservation of Nature (IUCN) also said its study showed that 57 per cent of all European bee species, which include types of bumblebees, honey-bees and solitary bees, were so little known that it was impossible to judge whether they were at risk or not.

Bees are vital to food production but are in decline in many parts of the world

“We’re laying down a benchmark” to help judge future trends, lead author Ana Nieto of the IUCN, which groups governments, scientists and conservationists, said. “We were shocked that there is not enough information for so many species.”

The bees’ work in pollinating crops is worth an estimated €22 billion a year in Europe, and €153 billion worldwide, states the study.

Cullum’s bumblebee, found in Europe and Asia, was among those most at risk and was rated ‘critically endangered’ because of the loss of its favourite clover flowers to farming.

The report said that threats to bees included more intensive farming, insecticides, and climate change − causing more heavy rainfalls, droughts and heatwaves that can harm bees and their access to food.