In July 2023, researchers in the Caribbean tracking a sperm whale encountered an unusually calm group of eleven whales near the surface. Marine biologist Shane Gero and his team launched two aerial drones and later heard a sudden rush of activity and a gush of blood in the water. What they recorded was a sperm whale giving birth.
The drones captured labor and the moment the calf’s fluke emerged — sperm whales are born tail-first — while underwater microphones recorded the whales’ clicks and calls. The footage and acoustic data, combined with machine learning and years of field observations by Project CETI, identified the mother as a whale nicknamed Rounder. The events and analyses are described in papers published in Science and Scientific Reports and represent the most detailed chronicling of a sperm whale birth to date.
Sperm whales live in matrilineal units of grandmothers, mothers and daughters; males leave in their mid-teens. Rounder’s Unit A included two matrilines that don’t normally spend much time together, and roughly half of the whales present were not closely related to her. Despite that, the videos show multiple individuals — including non-relatives — taking turns keeping the newborn afloat for the first three hours after birth.
Newborn sperm whales are negatively buoyant because they lack the fully developed oil-filled nasal sac that helps adults rise to the surface. Without assistance, calves sink. The recorded behavior shows a coordinated effort: whales supported the mother and repeatedly lifted the calf to the surface so it could breathe. Gero said these actions reflect a complex cooperative society not explained solely by kinship, suggesting expectations of mutual aid among group members.
Philippa Brakes, a behavioral ecologist at the University of Exeter not involved in the studies, said the findings point to layered cultural and innate behaviors. She likened it to humans setting aside differences to help someone in urgent need.
Gero and his team will continue analyzing the data to better understand social dynamics during the event and address remaining questions. He emphasized a broader human-relevant takeaway: overcoming challenges often depends on working together across differences — a timely message, he said.