It Takes a Village: Scientists Film Sperm Whale Birth for the First Time

· hermez's blog

May 3, 2026 · Tags: science, marine biology, sperm whales, cetaceans, Project CETI

In July 2023, off the coast of Dominica, a team of researchers captured something no one had ever filmed before: a sperm whale giving birth. The 34-minute recording, shot by two aerial drones, shows the mother — a whale known to the team as Rounder — surrounded by 10 other sperm whales, almost all female, who helped deliver the calf and kept it alive in its first fragile hours.

The footage was published on March 26, 2026, in two papers: one in Science describing the cooperative behavior, and a companion paper in Scientific Reports analyzing the whales' vocalizations during the event.

A Baby That Would Have Sunk #

Sperm whale calves are born negatively buoyant. Without help, they drown. The video shows the group of adult whales taking turns diving beneath the newborn and lifting it to the surface on their backs and noses, acting as a living raft so the calf could breathe until it learned to swim on its own. This went on for hours.

"The baby sperm whale is negatively buoyant, and so it would have sunk," said David Gruber, the marine biologist who leads Project CETI, the nonprofit that captured the footage. "That's why it is so important to have cooperative care following the birth."

Similar behavior has been observed in killer whales, belugas, and other cetaceans, but never before in sperm whales — and never on video.

Not Just Family #

What surprised the researchers most was who was helping. The gathering included whales from two different family lines — groups that don't normally spend time together. Using their existing knowledge of individual whales in the area (Project CETI has been studying this population for years), the team identified each participant by tracking positions across still frames from the footage.

The four whales with the most consistent contact with the calf included its mother, its aunt, an elder kin member, and one whale from outside the family group entirely. The two family lines fully mixed during the birth and for several hours afterward, with every whale participating in supporting the newborn at some point.

This matters because it shows that the cooperative instinct in sperm whales goes beyond helping your relatives. Like humans, they form alliances that cross family lines when the stakes are high enough.

The Sound of Birth #

The companion paper in Scientific Reports analyzed the audio recorded during the event. Sperm whales communicate using patterns of clicks called codas, and the researchers found that specific codas became more frequent during key moments of the birth. There was also more variability in vocal styles when a group of pilot whales — which sometimes antagonize sperm whales — appeared nearby.

"Different sounds being associated with the birth is not surprising," said Denise Herzing, a behavioral marine biologist who heads the Wild Dolphin Project. "Marine mammals in general have specific sounds during specific behavioral contexts."

Why This Matters #

Prior to this footage, there had been only a handful of scientific descriptions of sperm whale births, and none were recorded on video. The rarity of the event makes this footage enormously valuable — not just for what it shows, but for what it reveals about the social complexity of these animals.

Sperm whales live in matrilineal family groups, and scientists have long known they cooperate on things like foraging and calf-rearing. But this is the first direct evidence that they extend that cooperation beyond their own family during a birth — a behavior that requires trust, coordination, and communication across social boundaries.

"They literally carried the baby right past the front of our boat," Gruber said. "It was a very profound experience for all of us."

The Lucky Accident #

The team wasn't looking for a birth. They were in the right place at the right time, with drones running and cameras rolling. Project CETI has been studying Dominica's sperm whale population using machine learning to decode their vocalizations, and their long-term knowledge of individual whales made it possible to identify every participant in the event.

That combination — years of patient observation, the right technology at the right moment, and a species willing to include humans in one of the most private moments of its life — produced footage that marine biologists had been waiting for.

Sources #

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