On Friday 9th May RVCWG ran a bat walk at Minsterley Meadows open to members of the local community, a group of 16 made their way around the meadows with eyes on the skies scanning for bat activity. Attendee and RVCWG committee member, Julian Livsey kindly provided the following write up after the event.
” Friday evening, as the sun was dropping behind Long Mountain, my family and I headed for Minsterley Meadows to meet up with the Rea Valley Community Wildlife Group. The first of their free guided bat walks drew a good crowd of us, hoping to learn more about these amazing creatures. Our only experience of bats is one that visits the garden each summer, but we never really knew much about them.
Fifteen of us met up and were handed a detailed laminated sheet about the UK’s various bat species, and an electronic bat detector that we were advised to set to a frequency between 45 and 55 kHz. This would pick up our most common bats, the common and soprano pipistrelle.
As we set off on our loop of the Meadows SSSI site there was still just enough light to see the amazing Green-winged orchids that helped save this site from development. There were also plenty of moths and flies in the meadow, a feast for a hungry bat.
As we walked towards the far hedgerow, Ben, who was leading the walk gave us more information about the creatures we were here to see. Able to stay inactive for up to a week in poor weather, they are often most active about half an hour after sunset, each eating up to 3,000 bugs and insects every night. We learned about how their behaviour is changing due to street lighting. Their food source has moved out of its natural habitat towards our artificial lights, and the debate around how that might affect bat populations.
As the light levels dropped, along with the temperature, we saw our first bat. A noctule. Our largest bat species, we were told they fly quite high up to 18 metres, but often have a distinctive up and down pattern to their flight. For a moment we misheard this as them having a wingspan of 18 metres and a lot of incredulous and slightly terrified faces quickly turned to laughter.
A couple of people had their own detectors that heard the noctule bat before the rest of us saw it against the pale sky. This species communicates at more like 25 kHz so we retuned our detectors and picked up a few faint clicks as it raced off in the direction of the smoke from corned beef factory (probably not where it was actually going!)
At the top of the meadow we had a close encounter with a pipistrelle. Quite dark by now and coming towards the end of the walk, everyone’s glowing orange detectors suddenly lit up with a series of strong clicks and a black silhouette raced directly over our heads.
We were told bats use echo location, emitting a series of sound waves. These can be for helping them navigate, for finding food, or for communicating with other bats. Ben had a special detector attached to a tablet computer that showed the bat’s sound as a sonogram. The strong signals as a series of hockey stick shapes but a secondary set of sounds at a higher frequency. Apparently some species can do this, allowing them to communicate and navigate at the same time, perhaps trying to find a juicy moth while calling to its young pups to keep up. ”
