WINTER accommodation should be warm, dry and filled with natural daylight to offer some comfort at the beginning of November's long nights.But Thetford Forest's growing bat population needs homes, which are damp, dark, secluded – and preferably underground.

WINTER accommodation should be warm, dry and filled with natural daylight to offer some comfort at the beginning of November's long nights.

But Thetford Forest's growing bat population needs homes, which are damp, dark, secluded – and preferably underground.

However, as the natural caves and tunnels usually selected by the species are rare in East Anglia, man-made help has been drafted in.

With an artificial hibernaculum within the forest, constructed in an old air raid tunnel, already full to the rafters, officials keen to conserve their furry friends are now hoping to build an additional boarding house for their winter visitors.

"Bats need very specific underground conditions, with constant temperature and humidity levels, to allow them to hibernate undisturbed through the winter," said Anne Embry, funding manager at the Forestry Commission.

"Because of the nature of our landscape there are not too many such places around here, which is why we built the first hibernaculum – to help out.

"We have ten different species of bat currently in the area and six of these regularly spend at least part of the winter hibernating here.

"By creating a new hibernaculum in an area where we know there is a food supply, we are hoping to provide even more attractive accommodation for all bats."

Rare species, including Barbastellebats, have been seen using the existing 12-year-old hibernaculum, and it is hoped the new 30 metre-long habitat will encourage them to breed.

If £30,000 funding from grants and public donations is raised, work on creating the artificial habitat will begin in February. This will allow time for undergrowth to establish around the site by summer, with the bats welcomed to their new homes by next winter.

"The site we have chosen will provide a safe refuge, and is very close to the Little Ouse, where the species will hunt for insects," added Mrs Embry.

"The project will cost around £30,000, and we are looking to apply for funding from various conservation bodies. But it would be really nice if some local people could offer sponsorship and take a rear species in Breckland to their hearts."

Anyone interested in donating to the project can contact Mrs Embry, at the Forestry Commission, on 01842 810271.