Image copyright K Park Image caption Bumblebee feeding on a cornflower

Planting farmland with strips of flowers can boost the number of wild bumblebees, a study has confirmed.

Not only does it attract foraging bees, but it also encourages nesting, say researchers at University of Sussex.

In past decades, many bumblebee species have declined, due to a number of factors, including intensive farming.

The study, published in Molecular Ecology, suggest farms given funding to improve the environment can increase the size of wild bumblebee populations.

Rarer species could be helped by targeting planting on land near existing colonies and improving the plant quality of existing buffer strips and hedgerows Thomas Wood, University of Sussex

However, rarer species, which forage over shorter distances, may need special attention, as the method of management appeared to have no effect, said scientists.

Agri-environment schemes are now funded as part of the Common Agricultural Policy.

Higher Level Stewardship (HLS) farms are rewarded for planting strips along the side of fields with bee-friendly plants such as red clover, bird's-foot-trefoil and common knapweed.

The scientists analysed bumblebee populations on HLS farms in West Sussex and Hampshire over two years.

They found greater numbers of common bumblebee species and evidence of more nests on HLS farms, compared with farms without bee-friendly schemes.

Image copyright University of Sussex Image caption Strips of land on farms or road verges planted with flowers can boost bee numbers

However, for rarer bee species such as the common carder bee, there was little difference between the two types of farmland.

"The flower-rich strips on farms may be too few and too scattered in the landscape to benefit those species unable to cover larger distances," said Thomas Wood of the University of Sussex.

"These rarer species could be helped by targeting planting on land near existing colonies and improving the plant quality of existing buffer strips and hedgerows."

Red list alert

Insect pollination has been valued at around £690M per year for UK crop production.

A recent study found that nearly one in 10 of Europe's native wild bee species face extinction.

The European Red List, drawn up by the International Union for Conservation of Nature, found 9.2% of nearly 2,000 species are threatened with extinction.

Threats include loss of habitat from intensive farming, pesticide use, urban development and climate change.

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