Severe and widespread reductions in nighttime activity of nocturnal moths under modern artificial lighting spectra

To investigate how changing technologies for artificial nighttime lighting (e.g. streetlights) might impact nocturnal insects, we measured effects of exposure to different light-emitting diodes (LEDs) on activity in a range of common moth species. At light levels realistically experienced, we found substantial reductions in activity compared to natural nighttime conditions, not only under typical white LEDs, but also using lights expected to be less harmful, such as amber LEDs. These pervasive effects on activity, irrespective of light spectrum, suggest potential for severe consequences of light pollution on moth populations, and further highlight the importance of naturally dark skies.