The first guided walk

The first NWN (Norfolk Wild Nights) guided walk was held last week. The weather was foul and rain nearly stopped the walk form even starting, but 23 hardy souls turned up to hear about bats, moths and more. The weather was too bad to safely run a generator and so we did not run a moth trap. We began by having an introduction to bats and bat detectors. Firstly the Batbox duet, which is a hand held detector with heterodyne and frequency division settings. This is one of the best bat detectors for walks of this type as it has a loud speaker that plays bat sounds at frequencies audible to most humans. I also introduced the SM2 Bat and the Anabat detector, which are hand held or passive detectors- depending on the situation. 

This is a sonogram/spectrogram of a soprano pipistrelle, showing the characteristic 'hockey stick' shape calls of this species. The peak frequency is just over 55kHz. The picture is from a Echo Meter touch.


We walked along the river away from the church and along the water meadow stopping at likely roost features to discuss the general biology of bats. We saw and hear many birds, calling in the rain, which was constant and heavy. We held little hope of detecting bats. But hope was rewarded underneath the railway bridge where the group picked up the first bat of the evening a soprano pipistrelle. probably roosting in the bridge brickwork or a surrounding house. The bat made two passes and then headed elsewhere, but we had heard a bat! for the younger members of the Group (age range 3-70) this was their first bat and for others their first bat heard using detectors. As we walked back we picked up more soprano pipistrelles and some common pipistrelles foraging in the rain. Back at the church there were a couple of brown long eared bats visible in the street lights.  A success!, a few bats and a promise to return in fairer weather.