- Researchers from the Centre for Ecology and Hydrology carried out the study
- They examined 715,392 records submitted by volunteer nature observers
- They found the geographic range of bees and hoverflies declined by a quarter
- Rare, more specialist species were hit hardest by declines the research suggests
Britain's bee population is under threat - with one third of species suffering declines, research has shown.
The decline in bees and another key species, hoverflies, could spell trouble for Britain’s farmers in the future as they rely on the insects to pollinate crops.
But gardeners can help bees by letting parts of their lawns grow longer, experts say, and allow patches of wild flowers to grow.
While around 34 per cent of pollination is carried out by domesticated honeybees kept in hives, much of the rest of the work is carried out by bees and hoverflies.
The value of pollinating insects to the UK economy has been estimated at £690 million per year.
So any impact on the ‘services’ provided by bees and hoverflies could have a big financial impact.
Scientists examined 715,392 biological records submitted by volunteer nature observers between 1980 and 2013.
They found on average, the geographic range of bees and hoverflies declined by about a quarter, with greater losses in the upland areas of northern Britain where species fell by 55 per cent while species in southern Britain fell by 25 per cent.
In general, rarer, more specialist species were being hit hardest by declines, the research suggested.
Dr Gary Powney, from the Centre for Ecology and Hydrology in Wallingford, Oxfordshire, said: ‘A huge proportion of species are decreasing.’
There had been, however, increases in 12 per cent of species - mainly wild bees that act as ‘key pollinators’ for crops such as oilseed rape.
This may have been caused by environmental measures put in place by farmers, such as growing wild flowers in the margins of crop fields to encourage bumblebees, the research suggested.
Dr Powney said: ‘In many respects it is a worrying trend,’ which could have an impact on the UK’s food supply.
Explaining possible reasons for the decline, he said: ‘It is perhaps unsurprising, you have got ever intensifying agricultural systems, loss of key habitats nationally, you’ve got climate change.
‘For some pollinators you have introductions of diseases, you have invasive species, there are a myriad of pressures impacting on these populations.’