Light pollution is a significant and growing threat to wildlife, including many species of migratory birds. Every year, light pollution contributes to the death of millions of birds by altering the natural patterns of light and dark in ecosystems. As a result, light pollution can change birds’ migration patterns, foraging behaviors, and vocal communication. Birds are attracted by artificial light at night, particularly when there is a low cloud, fog, rain or when they’re flying at lower altitudes. This causes migrating birds to become disorientated and potentially circling in illuminated areas. Consequently, their depleted energy reserves put these birds at risk of exhaustion, predation, and fatal collision with buildings.

Satellite monitoring revealed that from 2012 to 2016,
artificially lit outdoor areas increased by 2.2% per year. Recent studies show that this number could be much greater.
Light pollution can change birds’ migration patterns, foraging behaviors, and vocal communication.