Through this documentary, 250 students from CM1, CM2, and 6th grade discovered the daily work of biologist Laurent Tillon (ONF), a specialist in bat ecology. Immersed in the fascinating world of these “ghosts of the night,” they explored the many methods used to better understand these discreet mammals: ecoacoustics, infrared video, colony monitoring, radio tracking, and health analyses.

Why study bats?

France is home to 35 species of bats, all of which are protected yet still poorly understood. The film helped students grasp their essential role in forest ecosystems and the threats they face.

Their way of life

French bats feed almost exclusively on insects, which they hunt at night using echolocation. They roost in colonies in tree cavities created by woodpeckers, where they raise their young while alternating between caring for them and nocturnal hunting.

Threats

They face numerous dangers :

• The loss of cavity-bearing trees or restricted access to old buildings that once served as shelters ;
• Collisions with vehicles on roads crossing forests ;
• Climate change, which disrupts seasonal cycles and food resources ;
• Fires (illustrated by the 2022 Landes forest fires) or extreme weather events that destroy their habitats ;
• The use of pesticides, which reduces insect populations ;
• Fungal or parasitic diseases…
   

Their role in the forest

Bats actively contribute to the natural regulation of insect pest populations. A single individual can consume up to 250 caterpillars per night, and an entire colony thus helps preserve forest health. Knowledge in support of forest management.

Laurent Tillon’s research contributes to improved forest management practices :

• Preserving cavity-bearing trees, which are essential for colony reproduction ;
• Designing forest roadside areas to reduce collisions, notably by maintaining canopy continuity that acts as ecological “bridges” ;
• Promoting a diversity of tree species and forest structures to provide more roosts and resources.

To learn more, consult a review of best practices in the book Chauves-souris et forêts, des alliées indispensables, co-written by Marine Lauer (CNPF) and Laurent Tillon (ONF). → Discover the book

Engaging discussions with students

Following the screening, Kévin Darras, an INRAE researcher at the EFNO unit (Forest Ecosystems), involved in the MONITOR, MASSIF, and BOSFOR projects of the PEPR FORESTT program, spoke with the young audience about his research in ecoacoustics and the images they had just seen.

Many curious questions were asked :

• “How do we hear bats?”
• “How does a bat ‘see’?”
• “Why do they hunt at night?”
• “Does it hurt when they are captured?”
• “Why was there a fire in the Landes forest?”
• …

A screening that may well inspire future scientific careers!

The Pariscience Festival

From October 3 to 27, Pariscience returns for its 21st edition. An international scientific film festival organized by the Association Science & Télévision, Pariscience offers a selection of films covering a wide range of scientific topics to appeal to all tastes and audiences. The program is designed for school groups from primary level to final year of high school, families, science and film enthusiasts, and professionals.

With the ambition of questioning, debating, and collectively reflecting on a desirable future, the Pariscience program aims to provide audiences with the tools to understand current scientific challenges and their societal impacts.

To learn more : https://pariscience.fr/festival-pariscience/