Scientists have shown the impact of light pollution on biodiversity in general, but the impact of low-intensity mostly surrounding urban areas is less well known.

Thanks to data collected over seven years of the Vigie-Chiro participatory science program in France, researchers estimated the effects of this diffuse pollution on common serotins.

This species, however, is rather tolerant of light is less abundant in landscapes polluted by artificial lightsummary on Wednesday in a press release by the National Museum of Natural History (MNHN).

In addition, its activity in the evening is later. In a medium -sized city, this activity is delayed by an average of 6 minutes on a clear night and 10 minutes in the event of cloud cover that amplifies the mix by reflecting light coming from the ground, according to the report. study published in the Diary Environmental Pollution.

A few minutes may seem trivial, but some bats are like serotonin no regular activity at night; they catch on a very strong peak after sunset, lead author Léa Mariton of MNHN told Agence France-Presse.

This peak should correspond to the presence of the insects they prey. if not, even a small change can have a profound effectadded the researcher.

Several hypotheses may explain the delay in the onset of serotine activity: a later release from the roost, less recognizable night, or a longer route to get to the hunting area.

A road with lampposts along it can be an impassable barrier for a bat, who must find another way.underlined Ms. Mariton.

Longer flying requires more energy, so more insects may not be there when it arrives.

The study shows the same change on moonlit nights. But, in this case, the bats can pay for on other nights, according to the study. In contrast, the artificial ones are almost constant, posing a long-term threat to the health of bats.

Thus, this study raises the question of the role of light pollution in the 30% decrease in the population of common serotines in France between 2006 and 2019, and of the possible impact on species that are more sensitive to light.

But light is just one of many threats to these demonic mammals, from habitat destruction to climate change to wind turbines.

To limit the range of light roughly, the study suggests specifically reducing the light intensity, changing the light spectrum or illumination directed at the ground.