Volunteers will listen for bats flying and feeding
Alloa's historic tower is to be surveyed for bats by conservationists.
National Trust for Scotland experts will check whether any of the mammals have made their home in the tower, which dates from the 14th Century.
The ancestral home of the Earls of Mar and one of Scotland's largest surviving medieval tower houses, the tower is among 17 properties being surveyed.
Experts, who said there were no known bat roosts at the tower, will begin their checks of the site next week.
The surveys are part of ongoing work to protect and conserve the bats and their roosts.
Conservationists will be checking for Soprano and Bandit Pipistrelles, brown long-eared bats, Daubenton's bats, Whiskered bats, the Noctule and the Natterer's bat.
Nature conservationist adviser Lindsay Mackinlay said the small size of the mammals often made it difficult to detect their presence.
He said: "They can squeeze into incredibly tight gaps and live in inaccessible parts of buildings and trees.
"We don't know of any roosting at Alloa Tower, but it's important to check so that we can make sure these creatures and their habitats are not disturbed."