One of the UK’s rarest bumblebees is being given a boost – by putting the flowers it feeds on in cages.

Conservationists and volunteers have planted 1,000 bilberry plants inside specially-designed metal cages that will protect them from grazing so they can provide food for the bilberry bumblebee in its Peak District stronghold.

The bilberries, which flower in the spring and early summer before heather and other moorland plants, are a vital food source for the bilberry bumblebee and its larvae.

But tender young bilberry plants are also a favourite of grazing animals such as deer and sheep, stunting the bushes’ growth and leading to a lack of mature plants that the threatened bee favours.

So bilberry has been planted across 60 acres of Hathersage Moor near Sheffield and protected by cages by the Bumblebee Conservation Trust and the Eastern Moors Partnership between the RSPB and National Trust.

In the past, grazing pressure on the moor has led to a lack of mature bilberry bushes, and the new project will build on changes in how the land is managed – which has already seen bilberry begin to make a comeback.

The bilberry bumblebee relies on mature bilberry bushes (Steven Falk/PA)
The bilberry bumblebee relies on mature bilberry bushes (Steven Falk/PA)

The new cages are designed to blend into the landscape and will be left in place while the plants get established.

They will allow the bilberry bumblebees to get to the bushes to feed and nest in the ground near their food source, while protecting the young bushes from grazing.

They are designed to boost numbers of the rare bee, which is also known as the blaeberry or mountain bumblebee and is found almost exclusively on bilberry-rich moorlands where it helps the plant by pollinating it.

Bilberry bumblebees were once found widely across north and west Britain, but they have seen dramatic declines and the Peak District is now one of their last strongholds.

The cold-loving upland species is expected to decline further because of climate change, experts warn.

Sally Cuckney, pollinating the peak project manager for the Bumblebee Conservation Trust, said: “Grazing animals such as sheep and deer find tender young bilberry plants especially tasty, and their constant browsing stunts the plants’ growth.

“That’s bad news for the bilberry bumblebee. If grazing is reduced, bilberry does much better.

“This hands-on project is the first attempt to help bilberry bumblebees and bilberry plants survive and thrive together like this.”

The project to help the bee is part of the Bumblebee Conservation Trust’s pollinating the peak project, backed by a range of partners with support from a £720,000 National Lottery Heritage Fund grant.

The initiative will also see volunteers monitoring bumblebees on the moor throughout the summer to help experts gather new data about the bees, the creation of flower-rich habitats and efforts to raise awareness.