Light Pollution Extends Birdsong Across Multiple Continents

A comprehensive global study reveals that artificial light pollution is causing birds to extend their daily singing by an average of 50 minutes, starting earlier in the morning and continuing later into the evening. Researchers analyzed over 4 million birdcalls from more than 500 species using data from the BirdWeather project, which combines citizen science audio recordings with satellite light pollution data. The findings show that birds in well-lit urban areas have nearly an hour longer active days compared to those in darker environments, with species having larger eyes and open nests being more affected. While this extended activity could provide more time for foraging or feeding young, it also likely reduces critical resting periods, especially during the breeding season. The long-term effects on bird fitness and survival remain uncertain, highlighting a need for further research into how light pollution disrupts natural behaviors and biological rhythms. This study underscores the growing ecological impact of artificial lighting on wildlife worldwide.