Effects of Artificial Light at Night on Zebra Finch Nocturnal Behavior

Abstract

With more of the world's population living in urban areas every year, artificial light is becoming an increasingly pervasive pollutant worldwide. It is important to study the potential effects of artificial light at night (ALAN) exposure, particularly on diurnal vertebrates. Previous studies have shown that ALAN suppresses melatonin and increases nighttime activity, however, studies quantifying specific behaviors taking place under exposure to dim ALAN are lacking. I exposed zebra finches (Taeniopygia guttata) to dim ALAN (1.5 lux) and used infrared video recording to test how ALAN affects specific nocturnal behaviors. I recorded body movement, hopping, grooming, eating, and drinking at four timepoints in the night (17:00, 21:00, 2:00, and 6:00). After 4 days of ALAN exposure, activity significantly increased for all ALAN-exposed individuals, including increased eating behavior. I provide evidence that suggests dim ALAN is enough to alter overall nocturnal behavior and specific activity levels.