Steinhausen, 12.07.2024
Bats, the hunters of the dark, are fascinating nocturnal animals
As part of the "Wild Neighbours Zug" project, five evening bat excursions are taking place in the canton of Zug this summer. This is because the shy hunters only reveal themselves at nightfall. The Zuger Zeitung newspaper attended one of them, in Steinhausen.
As dusk falls, it becomes quiet on the Dorfplatz in Steinhausen. There's still time for a lesson in bat science before the group of interested people dedicate themselves to observing the shy animals. Environmental educator Isabelle Bögli, who offers bat excursions as part of the "Wild Neighbours Zug: Bats in Settlement Areas" project, has arrived with a rucksack full of tools.
The expert shows the image of a bat in flight, which clearly shows that its five extremely long fingers extend over the entire flight skin and that this also encloses the animal's legs. A perfect flying body, fine and light, as if made for nocturnal hunting.
Great diversity of species in Zug
"15 of the 30 species that exist in Switzerland have been recorded in the canton of Zug," says the expert from Mühlau. That is a comparatively high number. She asks those present to estimate how light the smallest, and how heavy the largest bat species is. "The large mouse-eared batweighs up to 40 grams," she says, solving the riddle." The mosquito bat weighs about four grams." Hardly more than a bumblebee.
The diet of the nocturnal hunter consists of all those insects that sometimes rob people of their sleep or give them the creeps: "Mosquitoes, moths, spiders, millipedes, cockchafer beetles and so on," lists Isabelle Bögli. What's more, these nimble flying acrobats are so quiet that they are barely noticed. "You can hear them when they are communicating with each other, but not when they are hunting. Then they orientate themselves by the echo of their ultrasonic direction-finding calls, which are inaudible to us."
Too much light and many dangers
You would thereby think that these guardians of human sleep would be welcome. Unfortunately, buildings today are usually built so tightly that the small mammals can no longer find any roosts, whereas in the past they found shelter in large numbers in wooden houses, stables and church towers. The bright lighting of streets and paths all night long also deters the animals. "They should install dimmed lights with motion sensors," advises Isabelle Bögli.
The excursion participants learn a lot about bats from environmental educator Isabelle Bögli. Photo: Cornelia Bisch
This pretty little fellow is called the pipistrelle bat or "Pipistrellus nathusii" and can be found all over Switzerland. Photo: zvg
Excursion leader Isabelle Bögli shows the specimen of a bat in flight
The participants dissolved bat droppings in water and discovered insect remains in them Photos: Cornelia Bisch
For obvious reasons, this bat is called the "brown long-eared bat". It weighs five to twelve grams, and is on the Red List of endangered species
One of the smallest night hunters, the pipistrelle bat, weighs just three to eight grams. It is not considered endangered in Switzerland Photos: zvg
Alongside humans, the common domestic cat and the marten are the main enemies of bats. "Some of them, such as the greater mouse-eared bat, hunt on the ground and are easy prey for predators." But even those that hunt in flight are often intercepted by domestic cats when they leave their roosts. "Domestic cats should therefore not be allowed outside after dusk."
The expert gives further tips:
- do not use pesticides in the garden
- keep plants that are pollinated at night - such as evening primrose or night violet,
- cover bodies of water,
- use non-toxic wood preservatives, and
- seek the advice of bat experts when remodelling.
The course participants learned a lot of interesting facts about the animals' rhythm of life, and then went on the hunt for them with detectors. The devices send out ultrasonic calls like Morse code, and the animals are even occasionally visible in flight.
Housing shortage for bats
The website of the Bat Protection Foundation (Stiftung Fledermaus) also provides interesting information about these nocturnal animals: half of all bat species in Switzerland are unfortunately on the Red List. Some of them are as small as a sugar cube, others have a wingspan of 40 centimetres.
All the reported bat roosts In the canton of Zug have been recorded in recent decades, but there are still gaps in knowledge, however, and it is often no longer known whether the roosts still exist and are being used. Anyone interested can help to find out how the bat roosts are doing (see section below).
If you have any questions or find injured animals, please contact the bat protection emergency telephone 041 758 07 34 or the cantonal bat protection officer Silvana Dober, 077 423 91 28, zug@fledermausschutz.ch.
Further bat excursions in the canton of Zug will take place as follows:
2 August in Zug,
19 August in Menzingen,
26 August in Unterägeri,
10 September in Rotkreuz.
Information and registration at zug.wildenachbarn.ch/agenda.
Note:
Everyone can join in the research
With its rivers, lakes and cultivated landscapes, the canton of Zug has a wide variety of habitats. Nevertheless, knowledge about the occurrence and distribution of these animal co-inhabitants is limited. For this reason, wildlife observations are being collected together with the population as part of the "Wild Neighbours" project. Volunteers are needed who would like to carry out acoustic surveys of bats on warm and dry summer evenings. The ultrasonic calls of bats are recorded in courtyards, backyards and public green spaces. If you would like to help out or take part in an excursion, you can find all the information you need at zug.wildenachbarn.ch.