Nocturnal Sleep Behavior and Vigilance of Incubating Common Terns (Sterna hirundo) at Two Inland Breeding Colonies

Although sleep is necessary for maintaining physiological and cognitive function in birds, nocturnal sleep behavior has yet to be documented for terns. Nocturnal sleep behavior and vigilance of incubating Common Terns (Sterna hirundo) were explored at two colonies, Gull Island (Ontario, Canada) for six years, and Little Island (New York, USA) throughout one breeding season, using ∼1-min interval, time-lapse images from infrared trail cameras....