Animals around the world now live under night skies that glow with light pollution — the excessive use of artificial light at night. Light from urban areas obscures stars that migrating birds rely on for navigation, attracts animals to dangerous places, and disrupts their sleeping patterns. But new Israeli research finds that the phenomenon is actually killing animals.
A study at Tel Aviv University’s School of Zoology tested the impact of prolonged low-intensity light pollution on two species of desert rodents — the golden spiny mouse, which is active during the day and sleeps at night, and the nocturnal common spiny mouse which is active at night and sleeps during the day.
“We assume that exposure to [artificial light at night] had impaired the animal’s immune response, leaving them with no protection against some unidentified pathogen. No abnormal mortality was recorded in any of the other enclosures, and as far as we are aware, no similar event has ever been documented by researchers before.”
“Different species developed activity patterns that correspond to these changes in light intensity and day length and developed anatomical, physiological, and behavioral adaptations suitable for day or night activity
The researchers also found that light pollution also impacted the rodents’ ability to reproduce.