Our friends at Wild Eton Wick are taking part in the National Bat Monitoring Program, so we took the opportunity to join them in what turned out to be a fascinating and exciting evening. Georgeta, Kanika and Sheila cycled to Eton Wick along the Jubilee River, and we all gathered just before dusk at St John's Church. We joined up with Claire, Tom and Andrew from Wild Eton Wick who led the survey and were our resident bat experts, as we were all novices. Claire gave us an introduction to the bats and how the survey would work. Kelley and Kanika took charge of the 2 bat detectors, one set at 45kHz to detect common pipistrelles, and the other set at 55kHz to detect soprano pipistrelles. The inaudible bat calls are picked up by an ultrasonic microphone and mixed with the output of a high frequency oscillator in the bat detector to produce a noise audible by us mere humans. Tom had a different instrument that scanned at all frequencies, and could report back on which species was present. The rest of us were looking for visual sightings of the bats, and any other mammals which might be around. We all spread out around the churchyard. As it got darker, both detectors started picking up bat activity, and everyone was very excited to see the bats flying around the trees and church. No one batted an eyelid to see such acro-bat-ics. Kelley even managed to video a bat flying overhead whilst the detector went bananas in the background. Noctule bats (the biggest British bat species) were also detected around the church. And all to the sounds of music floating across the fields from the Ride the Night event at Windsor racecourse. We eventually had to drag ourselves away - the cyclists made their way back to Maidenhead like bats out of hell to warm themselves up, whilst Sara had to contend with the Ride the Night cyclists on her way home. Thank you so much to Wild Eton Wick for inviting us along and enabling us to contribute to the survey, we all loved this task!