Usually displaying a nocturnal or crepuscular activity pattern, sloths are most active throughout the night and evening dusk. In order to optimize energy and avoid predators, wild sloths hide behind darkness. Predators like ocelots and harp eagles, which hunt by sight, find them more difficult to see since their motions are so slow, and they might mix with the tree canopy. Two strategies essential for sloth survival: moving largely during low-light hours helps them to have a low profile and lowers energy use.

Amazingly, sloths' natural day-night cycles (circadian rhythms) can be disturbed by artificial light pollution from urban development, therefore altering their behavior. Research on sloths in towns has revealed that artificial lights may affect their behavior; they become less nocturnal and spend more time hidden during the day. Their feeding, mating, and resting cycles could be disturbed, which stresses them and throws off their usual metabolic rhythms.

Moreover, environmental elements such as seasonal fluctuations in daylight hours or climatic conditions affect sloth behavior. Sloths often become less active during the rainy season since the lower temperatures reduce their need to forage extensively. Understanding these small adaptations to natural light helps conservationists design strategies for preserving sloth habitats, therefore allowing them to live in an environment that supports their particular rhythm and reduces the pressures associated with exposure to artificial light.