Animals with the most bizarre sleeping habits

Sleep looks very different across the animal kingdom. Some species snooze while flying, others sleep underwater, and a few barely sleep at all. Here are six animals whose bizarre sleeping habits showcase nature's incredible adaptations. (unsplash)

Alpine Swifts Sleep While Flying: Alpine swifts can stay airborne for months during migration and are believed to take brief naps while gliding through the air. This remarkable ability allows them to cover vast distances without regularly landing. (wikimedia commons)

Ducks Sleep With One Eye Open: Many ducks use unihemispheric sleep, where one half of the brain sleeps while the other remains awake. Ducks resting at the edge of a flock often keep the outward-facing eye open to watch for predators. (wikimedia commons)

Freshwater Turtles Can Breathe Through Their Rear Ends: During winter, some freshwater turtles hibernate underwater for months. They absorb oxygen through specialized tissues near their cloaca, allowing them to remain submerged while barely moving. (wikimedia commons)

Frigatebirds Sleep Mid-Flight: Great frigatebirds can sleep while soaring over the ocean during long journeys. They take tiny naps lasting only a few seconds at a time, sometimes resting one half of their brain while continuing to fly. (wikimedia commons)

Sea Otters Hold Hands While Sleeping: To avoid drifting away in ocean currents, sea otters often hold paws with one another or wrap themselves in floating kelp before falling asleep. This charming habit keeps families and groups together. (unsplash)

Sperm Whales Nap Upright: Sperm whales sleep in short bursts while floating vertically in the water, almost motionless. These "power naps" usually last only 10–20 minutes and are among the shortest sleep periods of any mammal. (wikimedia commons)