Nocturnal animals keep getting lost — and light pollution is to blame

Many nocturnal animal species use light from the moon and stars to migrate at night in search of food, shelter, or mates. But in our recent study, we uncovered how artificial light is disrupting these nightly migrations.

Electric lighting is transforming our world. Around 80{6fe526db6ef7b559514f2f4990546fdf37a35b93c5ba9b68aa72eaf397bd16d6} of the global population now lives in places where night skies are polluted with artificial light. A third of humanity can no longer see the Milky Way – the galaxy our solar system belongs to. But the light at night has deeper effects. In humans, nocturnal light pollution has been linked to sleep disorders, depression, obesity, and even some types of cancer.

Studies have shown that nocturnal animals modify their behavior even with slight changes in night time light levels. Dung beetles become disoriented when navigating landscapes if light pollution prevents them from seeing the stars. Light can also change how species interact with each other. Insects such as moths are more vulnerable to being eaten by bats when light reduces how effective they are at evading predators.

Moths crowding a street lamp at night.