Hopefully this spooky season there aren’t actually any Greater Horseshoe Bats in your cauldron! This particular species of bat is one of the rarest, and Cornwall’s protected landscape offers key habitats and heritage features where these critters call home. These sites, including our National Nature Reserves and Cornish Mining World Heritage Sites, are important because numbers of Greater Horseshoe Bats are barely a 10th of what they were 100 years ago.
These endangered Greater Horseshoe Bats, their roosts and hibernation sites, are the subject of extensive legal protection, specifically the Wildlife & Countryside Act 1981 and the European Habitats Directive.
So, what makes them spookily special?
According to experts, the Cornwall Mammal Group, much of our current knowledge of bats is relatively recent, and for many years all bats were just ‘bats’. In the Cornish language askel grohen (translated as leather wings) covers all the bat species. Now more than 1000 different bat species are known to science! We have 13 species recorded in Cornwall and 12 breeding in the county.
The Greater Horseshoe bat is one of our largest, weighing up to 34g with a wingspan of 40cm. That’s about the same as 34 paperclips or 12 pennies! It has a wonderful nose-leaf which is critical to their particular system of echolocation. Whereas most British bats emit their echolocation sounds from the mouth, horseshoe bats use the nose. The tablespoon-sized body is covered in buff-brown fur above and below and when the bats are roosting, they hang upside down and wrap their wings around their bodies. They are conspicuously larger than the only other British bat to roost in this fashion, the lesser horseshoe. Baby bats are called ‘pups’ and are weaned at 7 weeks.
They live in buildings, such as old farm buildings, and can use mine shafts and mining stacks to roost and breed, creating a great link to our Cornish heritage. They hang upside down on overhanging hedge branches and (amongst other things) eat flying dung beetles. This means that mature, bushy, Cornish hedges are important for them. Believe it or not, cattle are key for the Greater Horseshoe bat to thrive. If farmers can monitor their cattle dung for worm eggs, and avoid using wormers routinely, then this is better for the wildlife which lives in cow pats – and therefore better for bats!
One of our recent Farming in Protected Landscapes (FiPL) projects recently funded was to repair the cob walls and roof timbers of a small stone and cob building in the Marsland Nature Reserve, which is an important roost site for a number of bat species. Devon Wildlife Trust owns and manages Marsland Nature Reserve which straddles the Cornwall/ Devon border. The former barn and workshop at Gooseham Mill is an important bat roost for a number of species, including Lesser and Greater Horseshoes, well connected to wildlife rich habitats and surrounded by an area of broadleaved woodland. A section of the cob wall collapsed in February 2021 and an emergency repair was made to prevent further loss of the building. The FiPL project has funded some important aspects including;
Safeguarding the future of a substantial and strategically important bat roost and hibernation site.
Enhancement of the existing bat roost with partitioning to reduce bat disturbance.
Maintaining connectivity between a number of local Greater Horseshoe bat roosts.
Consolidation of a local vernacular building of heritage interest using traditional building techniques.
The newly repaired building will continue to be managed as an important habitat for bats providing a safe refuge for them now and in future years.
Our partners, including the National Trust and Natural England have lots more information about bats, bat events and how to help create bat-friendly environments. The Cornwall Mammal Group has a wealth of information too.