Sperm whales observed acting as midwives during a documented birth

Project CETI released detailed footage and underwater audio showing a group of sperm whales cooperating to help a mother, dubbed "Rounder," give birth; the researchers published the findings in Science and Scientific Reports.

Researchers at Project CETI released detailed images and underwater audio of a sperm whale birth observed in Caribbean waters. The footage captured a social unit of 11 whales reorganizing around a pregnant female nicknamed "Rounder." The actual delivery took about 34 minutes, and the group remained close for roughly two hours. The studies include machine-learning analysis of visual and audio data and were published in Science and Scientific Reports. Key observations: - Project CETI recorded a birth involving a female called "Rounder" and an 11-member unit in early July 2023. - The delivery itself lasted about 34 minutes, and the whales stayed grouped near the surface for around two hours before dispersing. - Non-kin members of the unit participated in care, including actions that appeared to help keep the newborn calf afloat. - Underwater audio showed changes in vocal behaviour during the event, and researchers used machine learning to quantify temporary shifts in social structure. - The team combined the recording with a literature review noting similar cooperative births in other whale species. Summary: The recording documents a coordinated, group-level response to a birth in a sperm whale unit and adds quantitative detail to a rare set of wild cetacean birth observations. The researchers note that comparable behaviour in other species suggests such social midwifery could have deep evolutionary roots, while also advising caution in generalizing from a single event. Project CETI will continue studying these whales, including efforts to better understand their vocal behaviour.