With the notable exception of humans, most mammals give birth alone. But in July 2023, researchers in the Caribbean witnessed something extraordinary: sperm whales not only attending a birth but actively helping both mother and newborn.
Some of the whales present were not even related to the mother, known as Rounder. “Kinship barriers dissolved,” notes one of two studies published on the observation.
A team from the Cetacean Translation Initiative (CETI) was in the area to record sperm whale sounds for their ongoing work to decode whale communication. Equipped with underwater microphones, drones and cameras, Project CETI president and founder David Gruber said it was “a moment of pure serendipity and luck.”
The team noticed something unusual. Sperm whales are one of the deepest-diving whales; they spend much of their lives diving up to 2,000 meters (6,500 feet) deep hunting giant squid. But on that day, all 11 whales in a group known as unit A gathered near the surface, only taking very shallow dives and communicating so frequently, “it sounded like being in a popcorn machine,” Gruber said.
“Did Rounder communicate that she was about to go into labor and call the unit together? We don’t know. We just know that they were ready and they were prepared.”
What followed is the only known example of marine mammals helping in the birth of a non-kin.
The calf emerged, tail first, and after 34 minutes was delivered to a waiting circle of whales who took turns supporting and lifting the newborn to the surface to breathe.
That help was crucial: Newborn sperm whales are negatively buoyant, meaning they are going to sink like a stone. “So, you’re giving birth to this rock in the ocean, in a mile deep water,” Gruber said.
For roughly six hours, the group actively supported the calf. Relatives, including the grandmother and aunts, helped alongside unrelated whales. The baby’s older sister played “a very significant role,” while the only male present was the least involved.
Sperm whales are already known for alloparenting, in which individuals, both related and non-kin, stay with calves at the surface while the mother hunts. This new observation suggests that such coordinated care begins at birth with “intense social interactions and collaboration that leads to what I call like a radical collaboration,” Gruber said.
CETI scientists have been observing these whales for decades. That familiarity made the study possible, Diana Reiss of Hunter College in New York, not directly involved with the study, said in a press release. “I’m not sure this unit would tolerate observers being so close in any other instance.”
The findings suggest cooperative care during birth may be an ancient evolutionary adaptation, dating back to the rise of toothed whales, some 36 million years ago.
The whole scene, representing millions of years of evolution and a reaffirmation of the social bonds that underpin sperm whale society, was over in six hours when “the baby and the mom swam off in the sunset,” Gruber said.
Banner image: A baby whale being lifted from the water. Image courtesy of Project CETI.
This story first appeared on Mongabay
This article is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.
You may republish this article, so long as you credit the authors and Mongabay, and do not change the text. Please include a link back to the original article.
