The momentum in favor of the night continues
The month of July was marked by two advances in the "night" mission led by the Périgord-Limousin Regional Natural Park: the updating of the light pollution map in the area, and the participation of a group of residents in the monitoring of new nocturnal species.
Efforts that bear fruit
The Périgord-Limousin Regional Natural Park has been committed for several years to preserving the quality of the night sky and therefore closely monitors the evolution of light pollution in the region. The Park's teams have just produced a new map of light pollution, the result of compiling data provided by Dark Sky Lab . Based on satellite data from 2023, it allows, for the first time, a direct comparison with 2019 data.
This comparative analysis offers valuable insight into the evolution of public and private lighting across the region. Some municipalities committed to nighttime lighting reduction policies or the renovation of their lighting infrastructure are seeing their efforts rewarded by a measurable decrease in artificial light levels (see maps below). These findings contribute to the collective discussion on implementing a coherent territorial dark network* that benefits nocturnal species.
Nocturnal biodiversity sentinels at work
Meanwhile, the Star Watchers group, facilitated by the Park, recently completed its monitoring campaign of nocturnal birds of prey. This group of residents, responsible for measuring light pollution for several years, recently expanded its mission to include monitoring nocturnal species. Thanks to a rigorous protocol implemented in the spring, participants contributed to improving knowledge about the local distribution of sensitive species such as the tawny owl, the long-eared owl, and the barn owl.
After raptors, the summer of 2025 is an opportunity for these volunteers to focus on two new groups of nocturnal animals. This year, the star watchers are participating in the participatory inventory of glow-worms and the monitoring of bats. For the latter, the volunteers are equipped with touchscreen tablets and sound recorders, allowing them to detect and locate these species, which are indicators of the ecological quality of the night.
Observe, measure, act... elected officials and residents alike have a vital role to play in preserving the nocturnal environment. These actions contribute to the Park's biodiversity strategy and contribute to national recognition of the quality of the Périgord-Limousin sky through the Park's application for the "International Dark Sky Reserve" label.
* The dark grid is the network of ecological corridors characterized by a certain darkness and used by nocturnal species.
