The horseshoe bat is a protected species in the UK
A colony of protected horseshoe bats living in derelict hospital buildings are set to get a purpose-built house.
The disused wards at Cefn Coed Hospital in Swansea are set to be demolished but work cannot begin until the bat have an alternative home to move into.
Now the ABM University NHS Trust is to submit a planning application to build the home in the hospital's grounds.
Its hoped the bat house could be ready for the creatures' spring return from their winter hibernation caves.
Paul Stauber, the trust's director of planning, said: "The buildings are disused wards and have been derelict for some time.
"They are not only an eyesore, but are subject to vandalism and theft, and we have had to put extra fencing and 24-hour security presence on site as a result.
The bat house will allow the old hospital wards to be demolished
"They need to be demolished, and we hope to start knocking them down early in 2009. But before that happens, the bats must have a new home ready.
Mr Stauber said the bat house will look little different from an average wooden garden shed.
But it has been carefully designed by the trust's consultant ecologists and bat experts from the Countryside Council for Wales to ensure it is the perfect habitat for the bats to thrive.
"We will shortly be asking the City and County of Swansea for planning permission to erect the bat house and, once that's done, we can begin demolishing the old buildings," added Mr Stauber.
The old wards at Cefn Coed have been targeted over the past year by vandals, and thieves eager to help themselves to valuable roofing lead, he said.
By stripping the roof they also exposed asbestos which for safety reasons has had to be made secure.
Mr Stauber added: "Thieves pretending to be trust and council workers have accessed the site via private nearby residences, and I am sure residents living nearby will be very glad to see these old buildings razed to the ground."
A specialist demolition team will dispose of the asbestos as the buildings come down.
The work is expected to take a few weeks and local residents will be kept informed about the timetable of works.
Another planning application will be made later to use most of the cleared hospital site for a housing development.
A small section, close to the hospital chapel, is also earmarked for replacement buildings for long-stay patients.