“Discovering Urban Bats” at the Montpellier-Nîmes School of Medicine

Where is the Molossus hiding?

This is the question being asked by chiropterologists, the scientists who study bats. The area around Saint-Pierre Cathedral and the buildings of the former medical school are home to one or more individuals of an unusual species, Cestoni’s bat (Tadarida teniotis). Native to tropical regions, Cestoni’s bat has adapted to our latitudes and colonized all Mediterranean regions as well as the Pyrenees and the Alps. This so-called high-flying species, which is among the largest bats in France, is most commonly found in cliff areas. However, acoustic monitoring has also confirmed its presence as far as downtown Montpellier, and it is even possible that some individuals have taken refuge on a tall building facade. While all other bats in France emit inaudible echolocation sounds (ultrasounds above 20 kHz), Cestoni’s bat is the only one to emit sounds within the audible range. If you listen closely, you might be lucky enough to hear its whistle (similar to the song of the song thrush) one hour after sunset.
The areas around buildings are also frequented by the three species of pipistrelle—tiny bats no bigger than a sugar cube that can usually be seen circling streetlights as soon as the sun goes down. Kuhl’s pipistrelle, common pipistrelle, and pygmy pipistrelle are indeed quite common in urban areas. Their highly adaptable nature allows them to find shelter in hollow trees, cracks in building facades, under roofs, or behind shutters. Some adventurous ones even venture into houses and apartments in late summer. Don’t worry—as insectivores, they won’t attack you. To see them in flight, simply look up at sunset. To hear them, however, you’ll need specialized listening equipment. This is what participants in the “Halloween” discovery tour—organized in partnership with the Montpellier Tourist Office—were able to experience around and within the inner courtyard of the former Faculty of Medicine. Accompanied by Thierry ALIGNAN (Canopée34) and Alexis BULAND (EGPN student), both passionate about these small flying mammals, the naturally curious participants were amazed by the sensory experience offered… Seeing with their ears…
New outings are expected to be organized next spring, as the bats gradually enter hibernation with the approach of winter… Except for Cestoni’s Molosse, which will remain active—albeit to a lesser extent during the coldest weeks—throughout the winter. Keep your ears open—you might just be lucky enough to hear it as you stroll after dark between the cathedral and the Jardin des Plantes. tsssssik, tsssssik, tsssssik, tsssssik…
Thierry Alignan
Photo credits: Thierry Alignan, Alexis Buland
Thiseducational program on bats, designed to raise awareness about these animals and dispel myths surrounding them, was organized in partnership with the Tourist Office to highlight the richness of our heritage and its unique features.

This educational activity for those curious about the animal world was led by a specialist (a chiropterologist) who, after a discussion and some explanations, invited participants to listen to the ultrasonic sounds emitted by bats using sensors that convert them into audible sound.

We will let you know the dates of upcoming themed tours.