In July 2023 researchers tracking a sperm whale in the Caribbean found an unusual scene: eleven animals lying quietly at the surface. Marine biologist Shane Gero launched two aerial drones to film the group and, about an hour later, the calm exploded into thrashing and a rush of blood. What the team had first feared was a predator attack turned out to be a birth. The drones captured labor and the moment the newborn’s fluke appeared — sperm whales are born tail-first — while underwater microphones recorded the animals’ clicks, sounds Gero decodes as lead biologist for Project CETI.
Using drone video, machine learning, underwater acoustics and long-term field observations, the researchers identified the mother as a whale named Rounder and produced the most detailed record yet of a sperm whale birth, reported in papers in Science and Scientific Reports. Rounder was with Unit A, a matrilineal group that actually included two matrilines not usually tightly associated. About half the whales present were not closely related to the mother, yet all of them helped care for the newborn.
Newborn sperm whales are negatively buoyant because their nasal oil-filled sacs (the spermaceti system) are not yet developed; left alone they sink. Over the first three hours after birth, every whale present took turns supporting the calf at the surface so it could breathe. Individuals without genetic ties to Rounder repeatedly positioned and held the calf up, sometimes for extended stretches, while others supported the mother.
The observations suggest cooperative behavior that cannot be explained solely by close kinship. As Gero noted, the group’s responses point to a social expectation of mutual aid: animals help others so they, in turn, will be helped. Philippa Brakes, a behavioral ecologist at the University of Exeter who was not involved in the studies, said the results likely reflect both cultural and innate tendencies. She offered a human analogy: even if people have different preferences, most will respond to someone giving birth in the street.
The team is still analyzing the audio and video to map relationships, roles and communication during the event, and to answer remaining questions about how such cooperation is organized and maintained. Beyond the whale biology, Gero highlights a broader message: groups can overcome serious challenges by cooperating across differences, a lesson the researchers see as relevant beyond the ocean.