A third of wild pollinating insects are on the decline, study shows

Tom Clarke

Former Science Editor

A third of Britain's wild pollinating insects are in decline, a new study has shown. Credit: Steven Falk

If it was any other industry in decline, there'd be an outcry: It's worth nearly £700 million a year to the UK economy, its workforce get nothing close to the minimum wage, and most of them you wouldn't even recognise if you passed them in the street.

But that's the thing about pollination. It's run by insects. And being small, and being insects, they often get overlooked.

On top of that, apart from a few alarmist headlines from time to time, there is little hard data on the subject.

Losses in wildflowers and pollinators has a knock-on effect on the population of bees. Credit: Steven Falk

Now a group of leading UK researchers have completed one of the most comprehensive studies of the distribution of Britain's wild pollinating insects between 1980 and 2013 and found that a third of them are in decline.

"Wildflowers and pollinators rely on each other for survival. Losses in either are a major cause for concern when we consider the health and beauty of our natural environment," said study author Dr Gary Powney of the Centre for Ecology and Hydrology in Wallingford, Oxfordshire.

Bumblebees are perhaps the best known wild pollinators - that's everything except honeybees managed by humans - but there are hundreds more.

The study looked at the presence or absence of 139 species of wild bee and 214 species of hoverfly in 19 thousand sites across the UK.

Hoverflies that feed on crop plants have actually incresed over the last 30 years. Credit: Tom Clarke

Some like the Large Shaggy Bee, (Paunurgus banksianus), which nests along the edges of footpaths on the coast has declined by 54%.

Its heavyweight bumblebee cousin, the Red-shanked Carder Bee (Bombus ruderarius) was once widespread, is now found in only a few locations, having declined 42%.

But bees and hoverflies that specialise on feeding on crop plants have seen increases over the last 30 years.

The Ashy Mining Bee (Andrena cineraria) is five-times more widespread now than in 1980.

It's particularly well suited to oil seed rape, a crop which has expanded massively on UK farms over that period.

Overall, wild pollinators of our crops - around 11% of the total - have increased their ranges. This is a bonus for farmers, but not cause for celebration.

"While the increase in crop pollinators is good news, they are still a relatively small group of species," said Dr Powney.

"Therefore with species having declined overall, it would be risky to rely on this group to support the long-term food security of our country.

"If anything happens to them in future there would be fewer species to step up and fulfil the essential role of crop pollination."

The researchers relied almost solely on data from amateur "recorders", experts on certain species of bee or hoverfly who measure the abundance of species in their area.

They're also looking to the public for assistance through the UK Pollinator Monitoring Scheme (PoMS).