Hearing Bats in the Night

Standing outside the Vienna Botanical Gardens we turn our ears upward and outward looking for bats (Photo credit: Chloé Bolton).

In August 2025, one of the last summer nights before autumn was set to arrive and I find myself standing with my children in front of the Botanical Garden in Vienna, ready to encounter a species most of us rarely pay attention to and often have ambiguous feelings about: the bat.  Rym „Batwoman“ Nouioua, an expert from the University of Vienna, is taking a small group of scholars and their children on a nature walk to listen and learn about bats.

To say my children are excited would be an understatement. Finn, 9, knows a lot about everything and even more about bats and Milla, 5, is anxious and doesn't quite believe that most bats don't drink human blood. Rym quickly assures her that blood-drinking bats are not found in Austria. And we learn that there are at least 27 species of bats in the city who eat insects.

Rym is kitted out with a range of bat detectors that help us to eavesdrop on the flying mammals in the Garden.  Bat calls and echolocation happen at higher frequencies than adult ears can usually hear. Bat detectors enable humans to literally ‘tune in’ to bats and hear what they are up to. While many such detectors are available on the market, Rym also builds her own. She even hosts soldering workshops with school kids who can then use their very own detector to learn about the animals' echolocation. Or perhaps they could lend them to their parents, because unlike adults many children can hear bat's high-pitched sounds. Still at the entrance we start to listen with the bat detector and soon realize that we are not alone under the trees.  The bats’ ultrasonic squeaks, clicks, and chirps fill the night sky.

Rym „Batwoman“ Nouioua, an expert from the University of Vienna, teaches us about bat life in Vienna  (Photo credit: Chloé Bolton).

Walking with Rym was a rare opportunity to become nocturnal for a moment and realize how many animals surround us, how they literally even touch our heads without us being aware. And it’s not only bats who move through the city at night. While we slowly walked our way to the pond different members of our group heard squirrels and hedgehogs. There have also been nocturnal sightings elsewhere in the city of foxes, rats, badgers, and even wild boar!

While we can hear many bats in the night, we also learn that these creatures need some help in the urban environment. Bats’ roosts are sometimes destroyed from tree pruning, bats have negative encounters with cats, and they don’t always easily find food and water. Bats who are injured, dehydrated, or in need of help rely heavily on the work of dedicated conservationists and volunteers in the city – people like Rym who rehabilitate and release injured individuals and also put up nest boxes for bats to use. To learn more about their work visit The Austrian Bat Station.

Now, a few weeks later, I ask my children what they enjoyed about the night we walked with vats. Milla replies, "Hmmm... that I was afraid a bit... but that it was still really great... that I was allowed to stay awake real long... and that I actually heard my first bat!!" The longer she talks, the more I am convinced that I am looking at a next-generation batwoman who will follow in Rym's footsteps. Finn has continued his own exploration of bats and with his birthday fast approaching I plan to buy him a bat-detector. I’m already looking forward to learning more about the colony of bats in our backyard, and taking more forays into the night with my children.  

I find myself reflecting on not only how wonderful it was to provide the kids with an opportunity to engage with a female-scientist and conservationist as a role model but how important it was for my kids to fairly engage with bats. That is, to engage with bats on their own terms, to find ways of understanding their experiences of the world, and for thinking more about how cities are places in which humans and many other species live.