Could I ever have guessed before becoming immersed in the bucolic countryside of this precious corner of South Hams that tiny out-of-my-hearing-range and out of sight creatures with comedy noses and ears would be so captivating? And yet here we were, Mike & I, chasing up a dark country lane with bad detectors like light sabres crossing beams in hot pursuit of a Lesser Horseshoe bat.
The day started promisingly, as so many do, launching into a whole new area of flora or fauna. My experience of bats had been limited to the dark skimming shapes over a swimming pool in France in the balmy depths of a hot Summer’s evening. Bats, unlike the insects they consume, are a strangely approachable subset of the diverse wildlife into which we were plunging several times a week with enthusiasm and a varied range of little or no prior knowledge. There are 16 species in the UK, falling into only 2 families, the Horseshoes (Lesser and Greater) and 14 other bats in the Vesper family including pipistrelles, common and soprano. We pored over our ID cards, talking through the key features of each bat. We learned about different forms of echo location; discussed habitats; flight patterns; EU protection status; planning and site related issues and geographical spread.
The learning process at Ambios almost always involves a combination of classroom (yurt!) based learning, wider reflections and discussions about the importance of the subject under study and its habitat in rewilding and then some practical or action based learning. We would learn plant ID and produce posters of major flower families with their key characteristics and then identify them outside as part of a field survey to measure the progress of the rewilding plan. We would learn about key habitat descriptions and then survey the local woods using new terminology with surprising confidence and pleasure. We learned about birds’ shapes and colours and their songs and calls. We took every opportunity in the woods and fields to identify them visually or by sound.
But bats… they are altogether a different matter! We spent the afternoon getting to grips with Anabat software so we could analyse their sound, often occurring at a frequency outside the range of all but the tenderest teenage ear. (So that was me out for a start). We picked through hundreds of last Summer’s night time recordings visualized as a series of dashes and hockey stick shapes at magic intervals around the right frequencies – 40/45; 55; 80; 110 MHz – trying to identify different species of bats and avoid the white noise of a thousand insects….It was strangely satisfying and a whole new use for a computer screen but after several hours it was time for a break and off for an early dinner so we could be out by 7:30pm for an evening of bat rustling….
And so we found ourselves, a group of six relative strangers, brandishing our bat detectors at bushes and into the air, setting a range of frequencies to detect a variety of bats, and hoping against hope that the relatively rare (except – happy days – in this neck of the woods) Lesser or Greater Horseshoes would come out to play. We detected pipistrelles, common and soprano; we even saw them flying over us. The Horseshoes were known to roost less than a mile up the road and Mike explained that they tended to use the path we were on as a highway and showed us how to direct our beam to get the best chance of detecting them for more than a second or two. My detector was set for 110MHz – Lesser Horseshoe sound territory – and I stepped aside from the group trying to ensure that, should a bat come through, I had a clear line of sight and minimized the chance of interference.
I waited hopefully. Others with lower frequencies were picking up common and soprano pipistrelles. I toyed with the temptation of a lower frequency for the pleasure of finding a bat in my beam, but held out for what I was beginning to see as the greater Lesser Horseshoe prize.
As the light fell further, I picked up one and then another Horseshoe. Yesss! Despite the fact that I had seen nothing and heard nothing but the convincing hum of the detector, the physicality of the swoop past brought alive the afternoon’s data magically. But the detection was momentary, a few seconds at most, and at a distance. We turned up the path to set off for another location and I resigned myself to having had my fill of Lesser Horseshoes. Suddenly a late ‘appearance’! My detector came alive at 111MHz and I shouted to Mike who changed frequency and picked it up too. He grabbed my sleeve and we dashed up the lane following the increasing noise from our devices, the beams converging enticingly. Our Lesser Horseshoe was teasing us with its invisible proximity. Finally we were able to slow down and stalk it through the gloom until our detectors had passed like a party game from cool to warm to screaming hot and we were probably no more than 60cm away from it. We squinted in the half light into an enormous laurel growing out of a bank, alive with the sound of our bat. We didn’t see it and we didn’t ‘actually’ hear it but the moment of triumph and exhilaration will stick with me for a very long time.