When darkness falls, turtle activities vary significantly, often surprising those who only observe them during the day. Their behaviors are influenced by species, habitat, and environmental conditions, ranging from deep slumber to active foraging.
How Turtles Rest and Sleep
For many turtle species, nighttime is a period of rest. Their sleep is a resting state where metabolism slows, conserving energy. Aquatic turtles, such as red-eared sliders and painted turtles, often sleep underwater for hours. Some species, like musk and painted turtles, absorb oxygen directly from water through specialized membranes. They may rest fully submerged, or with their head slightly out of the water, holding their breath for extended periods.
Terrestrial turtles, like tortoises, find sheltered spots on land to rest. They may withdraw into their shells for protection, or burrow into soft ground or leaf litter. This resting state is important for their physiological processes, as their body temperature and metabolism are influenced by surroundings.
Nighttime Activities of Some Turtles
While many turtles are diurnal, some species are nocturnal or crepuscular (dawn/dusk). Common snapping turtles and alligator snapping turtles are nocturnal predators, using darkness to ambush prey like fish, amphibians, and small mammals. They also scavenge for carrion and aquatic plants at night.
Sea turtles, while often diurnal, engage in nocturnal activities. Female sea turtles come ashore at night to lay eggs, a behavior thought to avoid daytime heat and reduce predation risk. Hatchling sea turtles emerge from nests at night, orienting towards the ocean’s brighter horizon. Some green sea turtles forage at night, particularly when moonlight is sufficient.
Where Turtles Seek Shelter
Turtles use various shelters at night for safety, thermoregulation, and resting. Aquatic turtles often wedge into rock crevices, submerged logs, or man-made structures like dams. Some burrow into mud at the bottom of a pond or lake, especially during colder periods, to regulate body temperature and conserve energy.
Terrestrial species seek natural hiding spots. Box turtles may burrow into leaf litter or find dense vegetation, like blackberry tangles, offering concealment and protection from predators. Desert tortoises retreat into burrows or rock shelters to escape extreme temperatures, using these underground spaces for stable overnight conditions.
Differences Across Turtle Types
Nighttime behaviors of turtles vary based on whether they are aquatic, terrestrial, or semi-aquatic, and the climate they inhabit. Most tortoises are diurnal, spending nights hidden in burrows or dense vegetation. North American box turtles are also predominantly diurnal.
In contrast, some Asian box turtles, mud turtles, and musk turtles are more active after dark, foraging in ponds. Aquatic basking species like red-eared sliders and painted turtles are diurnal, though their sleeping habits vary. Some prefer to sleep underwater, others on dry platforms.
Nocturnal basking, where freshwater turtles emerge from water at night to warm up, has been observed in tropical and subtropical regions. This suggests a response to warm water temperatures. Individual and environmental factors create variations in what turtles do once night falls.