Century of records shows broad decline in Europe's wild bees and hoverflies
Most of Europe's wild bee species and about half of its hoverfly species have declined over the last century, according to a study that analysed pollinator records going back to 1921. The analysis covers 88% of bee and hoverfly species across Europe, making it one of the broadest assessments of its kind. The Guardian
Bees and hoverflies carry pollen between flowers, a service that allows many plants to produce seeds and fruit. Nearly 90% of wild flowering plants depend in part on animal pollination. More than three-quarters of major food crop types depend in part on animal pollination.
The study was led by Carlos Martínez-Núñez, an ecologist at the Spanish National Research Council. His team tracked changes in where species occur and how frequently they are found, rather than counting individual insects.
The pattern was not uniform. More bee species are declining than increasing in all parts of Europe except the Alpine region. Species richness, the number of species found in an area, fell persistently in the Atlantic and Continental regions for both bees and hoverflies.
The researchers said they do not expect widespread pollinator extinctions to have occurred yet in Europe. Their data show 91% of species logged over the last century were recorded at least once in the modern period between 2001 and 2020. What has mostly fallen is occupancy, the probability of a species being found at a given site, meaning many species persist but in fewer places.
The findings were reported as diplomats gather in Yerevan, Armenia, for COP17, the 17th UN biodiversity conference on conservation and sustainable use of nature.
Other recent assessments point to continued pressure on pollinators. In Europe, nearly 40% of hoverfly species, 20% of butterfly species and 9% of bee species are threatened with extinction, according to the European Environment Agency. EEA A 2022 assessment found 37% of all hoverfly species in Europe threatened with extinction. IUCN Monitoring data for 2017 to 2024 showed hoverflies with declines of between 26% to 37% over the eight-year period. UK Centre for Ecology & Hydrology
