I am huddled over a little black box that’s emitting curious clicking noises. It reminds me of Second World War films in which earnest people sit over crackly Bakelite radios attempting to decipher coded messages. Above me, the night sky sheds just enough light from a waning moon to illuminate a group of shadowy figures similarly huddled. We are listening intently for evidence to confirm our belief that there is something out there. A casual passer-by might possibly view our late-night presence with some disquiet.
I am with local naturalist Dr Johnny Birks at dusk on the very beautiful Malvern Hills, but for some reason we are standing in a car park. ‘From here we have a chance of seeing or hearing perhaps five or six different species.’ Johnny’s enthusiasm is infectious, and soon we are all looking and listening for signs of bats as they emerge from their day roosts to forage for insects in the woodland canopy.
I am a bat fan, but my knowledge is lacking and I have come here to learn more about these misunderstood mammals. For some time now, I have been on a quest to meet a breed of people who spend their lives professionally and voluntarily helping to conserve Britain’s seventeen bat species; species that share similar lifestyles but have their own idiosyncrasies.
The black boxes burst into life once more, but this time I can only describe it as a kind of warbling whistle. ‘A lesser horseshoe bat!’ In true Johnny Morris style, Johnny performs a remarkable imitation of the echolocation call of one of our tiniest bats — as decoded by our bat detectors. Lesser horseshoe bats clearly like to stand out from the crowd. ‘This warble’, explains Johnny, ‘results from their use of Doppler effects when echolocating.’ I’m lost already. Horseshoe bats behave differently to other British bats in another way too: rather than crawl into cracks or crevices or hide behind tiles or bargeboards, they prefer to roost hanging by their feet, with their faces just visible through their shawl of winged limbs. If you are lucky enough to witness roosting horseshoe bats, you may see them gently swinging to and fro, rather like a gymnast about to start a routine on the high bars. They have switched on their directional sonar and are detecting your whereabouts. They know you are there.
I discover that despite being in an unremarkable car park, I am in fact standing within metres of one of the largest maternity colonies of lesser horseshoe bats in Britain — some 700 females gathered together to give birth and raise their young. Astonishingly, this roost had gone undetected until local bat enthusiasts became intent on finding the summer roost site of a colony of bats known to hibernate in a nearby disused railway tunnel. Using radio-tracking technology, they were able to follow the bats to a largely unoccupied country house just a short distance over the crest of the hills. It was an extraordinary discovery.
Not long before, I had visited a similarly large lesser horseshoe maternity roost in the Usk Valley in Wales with David Jermyn of The Vincent Wildlife Trust. There the bats inhabited a once rather fine Victorian coach house and stable block that once served the nearby mansion. Lesser horseshoe bats certainly know how to live, and often express a preference for old country houses. As dusk fell, a bat or two flew out of the upper floor of the stable building and then flew back in — had my presence been felt? David explained to me that the bats were in fact ‘light sampling’, another behavioural characteristic of horseshoe bats, which they carry out at both dawn and dusk. It is thought that this sampling is a mechanism for resetting their circadian rhythm — surely necessary if you live in total darkness.
The light sampling carried on for some time, but as darkness fell a trickle of bats began to emerge. The trickle soon turned into a torrent, as bats streamed out of a carefully designed exit point. Within minutes several hundred lesser horseshoe bats had flown silently into the night to forage, travelling up to 3 or 4 km in search of insect prey before returning to suckle their young. I stood there wondering if those living close by knew that they were neighbours to one of the largest colonies of lesser horseshoe bats in Western Europe, with over 1000 bats. Close to the old stable and coach house lay another relic of a bygone era: an icehouse, now well camouflaged by encroaching woodland. How clever these bats are to have an adjacent winter residence; a secret rural retreat, nicely insulated from extremes of temperature, but cold enough for them to reduce their body temperature and lower their metabolism. It is here that many will spend the winter months, occasionally waking to find food and water during milder spells.
It isn’t only lesser horseshoe bats that have a taste for luxury accommodation. I was reminded of an earlier visit, to Dorset, where I was led to another country house, more specifically the ‘Old Kitchens’ where meals were once prepared for the aristocratic household. My guide then was Colin Morris, manager of this ‘Horseshoe Hilton’ as he fondly calls it, which is home to some 250 greater horseshoe bats, the very much larger cousin of the lesser horseshoe. The eighteenth-century building had a faded Georgian neoclassical feel, its ecclesiastical windows infilled with rather more brutalist breeze blocks, and the façade was now festooned with tapestries of moss and lichen. It was clearly no longer a kitchen. Inside the building Colin has created ‘living spaces’, with different temperature and humidity properties to allow the bats to move around the building according to their needs. I was allowed only a brief spell inside the building; Colin was anxious that I did not disturb his guests. A couple of bats were loitering in the lobby, suspended like tiny lanterns from an oak beam. One of the bats unwrapped its papery cloak just enough for me to see its tiny face. They have a comical appearance; their horseshoe-shaped nose-leaf, part of their echolocation system, resembling a pig’s snout from a distance.
Outside the Horseshoe Hilton is plenty of woodland cover with hedgerows kept deliberately unkempt — an ideal hunting ground for a species that normally seeks its prey by aerial hawking, but has also developed the rather laid-back hunting strategy of simply hanging from an overhanging twig and pouncing on a passing cockchafer. The pièce de résistance of this site is a hibernation cave, excavated into the chalk at the back of the building and believed to be the first cave dug out of solid rock just for bats. ‘Some forty tonnes of chalk was removed by a team of volunteers in just one weekend,’ Colin explains. ‘The tunnel was later extended and its presence now means that the bats can stay on site during the long winter hibernation, transferring back to the kitchens as spring arrives.’ The tunnel has also led to the colony size more than doubling. It is quite humbling to witness the commitment of people like Colin, David and Johnny to bat conservation.
Back in the car park, Johnny guides us to the edge of a small reservoir tucked in the lee of the hills. As we stand looking into the blackness, I hear what I think is a fox barking across the water. ‘Muntjac,’ says Johnny. ‘Sometimes called the barking deer.’ I make a mental note to learn the difference. The barking continues for some time, breaking into the silence of the hills. The mise en scène has a black theme: the water is black, the hillside beyond is black, the shape flying over the water is also black. The shape is a Daubenton’s bat. It is clear to see why it is referred to as the ‘water bat’: it swoops back and forth pendulum-like, skimming the surface with wonderful agility to scoop up midges, caddis flies and other insects with its large feet.
We move on again in search of woodland bat species. The track we are following is unlit and enclosed by dense tree cover. We talk in hushed voices waiting for our black boxes to wake from their torpor. To our right, the ground falls away steeply, the woodland clinging at times to an almost vertical face, one of the many quarry faces that scar the Malvern Hills. Our bat detectors are not sophisticated affairs and may not be picking up all the bat species around us — but they are there, leading their secret nocturnal lives. Johnny tells us that one bat known to roost in these woodlands, and one very much partial to moths, is the rare barbastelle, but the black boxes remain mute: it is as if word of our presence has got around. The wood stays silent. We stay silent. The boxes stay silent.
This bat walk is over, but my journey of discovery will continue as I meet with more of our bat conservationists, and each time I will learn just a little bit more about the ecology of this extraordinary group of animals, often maligned, but capable of inspiring so much fascination and enthusiasm. Writing this, I remember a recent text message I received from a graduate intern currently working with me. Immediately after visiting her first bat roost, she wrote; ‘I’ve just seen my first ever lesser horseshoe bat!!! So amazing and SO ADORABLE. Incredible to see those bats up so close…I think it’s safe to say I’ve found my new favourite animal, which means giraffes will have to move over!’. If more people could share her experience and the joy that followed, perhaps they too would have a moment of epiphany — bats definitely do need more friends.
HILARY MACMILLAN is the Communications Manager for The Vincent Wildlife Trust and also works as a teacher of young people with specific learning difficulties. In 1991, she won the highly commended category of the prestigious Sir Peter Kent Conservation Book Prize. More recently, in 2015, she authored a book ‘From Mallards to Martens’ celebrating the 40th Anniversary of The Vincent Wildlife Trust and the work of the Trust’s founder, the late Honourable Vincent Weir.
Photos by FRANK GREENAWAY.