Artificial Light Has Essentially Lengthened Birds' Day (science.org)
(Friday August 22, 2025 @11:22AM (msmash)
from the grave-concerns dept.)
Light pollution [1]extends the active hours of birds worldwide [2]by nearly an hour , fundamentally altering the natural rhythms of over 500 species across multiple continents. Analysis of 60 million bird call recordings reveals that artificial lighting causes birds to begin vocalizing 20 minutes earlier each morning and continue 30 minutes later each evening. The effect varies significantly by species anatomy and behavior.
Birds with proportionally larger eyes experience the strongest responses, with American Robins in highly illuminated areas beginning their songs up to two hours before sunrise. Species nesting in tree cavities or enclosed spaces show minimal changes, as opaque barriers shield them from artificial light. The research, drawing from BirdWeather devices deployed globally by birdwatchers, is the largest analysis of light pollution's biological impacts to date.
[1] https://www.npr.org/2025/08/21/nx-s1-5507165/light-pollution-bird-day-hour-longer
[2] https://www.science.org/doi/10.1126/science.adv9472
Birds with proportionally larger eyes experience the strongest responses, with American Robins in highly illuminated areas beginning their songs up to two hours before sunrise. Species nesting in tree cavities or enclosed spaces show minimal changes, as opaque barriers shield them from artificial light. The research, drawing from BirdWeather devices deployed globally by birdwatchers, is the largest analysis of light pollution's biological impacts to date.
[1] https://www.npr.org/2025/08/21/nx-s1-5507165/light-pollution-bird-day-hour-longer
[2] https://www.science.org/doi/10.1126/science.adv9472