- Most comprehensive study undertaken finds average bee and hoverfly range down by a quarter
- Urban development, climate change and pesticides seen as main reasons
- However, some of the biggest pollinators have actually seen their ranges increase over the study period
The UK’s pollinators are under siege with a third of the country’s bee and hoverfly species declining significantly in the past 40 years, a new study finds.
Research into 353 species found that, on average, the area in which each can be found has shrunk by a quarter since 1980 – with many experiencing far greater drops in geographic range.
The declines are caused by urban development, pesticides and climate change and have raised concerns among conservationists who argue that pollinators are vital for crops and for the health of our wildlife.
More research needed
“This analysis sends us a warning. There is an urgent need for more robust data on patterns and causes of pollinator declines,” said co-author Claire Carvell, of the Centre for Ecology & Hydrology.
The study did contain one significant bright point, however, finding that 22 of the most important crop pollinators, responsible for the bulk of agricultural pollination, increased their range by 12 per cent between 1980 and 20013.
This is likely to be because there has been a significant increase in the flowering crops, such as oil-seed rape, that they feed on, the researchers said. Government-subsidised schemes to encourage farmers to plant more wildflowers could also help, they added.
The role of neonicotinoids
Despite the increase in key pollinators over the period of the study, the researchers cautioned that between 2006 and 2013 those species saw a 19 per cent decline in their range – which has been attributed in part to rapid rise of nerve-agent pesticides, known as neonicotinoids, during that period.
Neonicotinoids have been banned in Europe since the study ended in 2013 and researchers said they would be interested to see whether key pollinator ranges have returned to growth since that time as a result.
“While the increase in key crop pollinators is good news, they are still a relatively small group of species. It would be risky to rely on this group to support the long-term food security for our country,” said report author Gary Powney, of the Centre for Ecology & Hydrology.
The biggest gainer since 1980 include the Ashy Mining Bee, which has seen its range increase five fold, while the biggest loser is the Red-shanked Carder Bee, which is down 42 per cent.
Other benefits of pollinators
Non-crop pollinators are also vital for a healthy countryside because they pollinate wild flowers and provide food for other wildlife.
The study is the biggest of its kind, using more than 700,000 sighting records, mostly collected by expert naturalists.
It is published in the journal Nature Communications.