# Why do sperm whales blow bubbles while sleeping? Research reveals sperm whales blow bubbles to maintain balance during their underwater naps. - **Source:** [Popular Science](https://brifing.si/source/cc3d313a-759c-4802-b881-fc8585f35ef9) - **Published:** 2026-07-23 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/df2c0797-5a72-40eb-b586-da41aa2fb4ef ## Whales' sleeping habits Sperm whales take short 10-15 minute naps underwater in a vertical position with their heads pointing upwards. This keeps them away from turbulent surface waters, but their large, buoyant heads require a solution to prevent floating up during sleep. ## The secret of the bubbles Researchers discovered that whales blow bubbles while sleeping. This behavior helps them control their buoyancy underwater. Whales napping near the surface blow bubbles about 11 times per nap, while those in deeper waters only bubble 3-4 times. ## Pressure and buoyancy relationship High pressure in deep waters makes whales less buoyant, so those napping deep need fewer bubbles. Near the surface, whales release air from their lungs to control buoyancy, preventing them from floating up during sleep. ## Research process Forty-two sperm whales in Norway's Lofoten Islands were monitored using underwater sound recording devices. The devices were attached to the whales and later collected for data analysis, providing detailed insights into their sleep behaviors and bubble-blowing frequency. ## Conscious or unconscious? Researchers aren't yet certain whether whales blow bubbles consciously or unconsciously during sleep. It remains unclear if they sleep with half their brain awake like dolphins or enter full sleep like humans, given their need to regulate buoyancy. ## The mystery of marine mammals This study helps us understand the complex behaviors of sperm whales. Their strategies to adapt even during sleep raise new questions about the intelligence of marine mammals and their remarkable environmental awareness. ## Sources covering this story - https://www.popsci.com/environment/sperm-whales-bubbles-sleep/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._