What Happens When a Whale Is Born?
On a bright-blue morning in July, 2023, a team of researchers took off in a catamaran from the island of Dominica in search of sperm whales. Sperm whales communicate via bursts of clicks, called codas, and the researchers—part of a project called the Cetacean Translation Initiative, or CETI—are hoping one day to decipher what the codas mean. On this particular morning, they were looking to attach an electronic tag to a whale so they could record both its clicks and its movements.
After a couple of hours, they happened upon eleven sperm whales, bunched closely together at the surface. This behavior was odd enough that the researchers dropped their plan to tag a whale. They launched a pair of camera-equipped drones to hover above the group. After another hour or so, a great cloud of blood swirled through the water. Then a new gray head appeared. Thanks to a crazily unlikely accident, the researchers had witnessed a sperm-whale birth and had managed to videotape the entire event.
Thanks to another crazy accident, I was onboard the catamaran that day. Not only did I get to witness the birth but also I got to watch the normally sober-minded researchers react to it. The scene on the deck resembled something out of the Marx Brothers. Everyone raced to the front of the boat to get a better view. “Oh, my God,” one of the scientists said, clutching his head. “Oh, my God, oh, my God.”
“Holy fucking shit,” another exclaimed.
For the next two hours, the whales remained bunched together. They seemed to be nudging the baby around, but what, exactly, was going on was hard to say from the vantage of the catamaran.
The researchers spent almost two years analyzing the drone footage, applying machine learning in combination with good, old-fashioned field biology. Today, they released a pair of papers chronicling what happened that July morning, one in the journal Science, the other in Scientific Reports. Their findings suggest that the whales offered the calf’s mother a level of assistance that puts midwifery to shame.
“I think it’s very enlightening to see another species working with such coöperation and care for their group,” Project CETI’s founder, David Gruber, who teaches biology at the City University of New York, told me. “Meanwhile, we do horrible things to each other. So there’s something to learn from them.”
Sperm whales have the largest brains of any creature on Earth. (These can weigh up to twenty pounds.) They are also highly social animals. Females travel together in groups that may include anywhere from a few to a few dozen members, and they share child-rearing duties. Male calves remain with their group until they are about fifteen years old; after that, they lead solitary lives and approach female groups only to mate.
Though sperm whales are highly mobile—they can travel tens of thousands of miles in a single year—the ones that frequent the waters off Dominica return often enough that scientists have been able to determine which whales hang out together. (Individuals can be identified by the shapes of their flukes.)
From the drone footage, which captured the moment the baby whale’s fluke first emerged, the researchers were able to determine that a whale named Rounder was the mother. Rounder is a member of a social group called Unit A, which consists of two families that are not closely related. Rounder’s family includes her mother and her half sister. The other includes an older whale named Fruit Salad, along with Fruit Salad’s daughter and granddaughter.
When sperm-whale calves are born, weighing about a ton, they are pretty helpless. They can’t immediately swim—their flukes are bent from being cramped in the womb—and, to use the technical term, they are “negatively buoyant.” Left to their own devices, they will sink. What the footage showed is that, for the first three hours of the newborn’s life, the members of Unit A took turns keeping it afloat. At times, they nestled so close to the baby that they formed a sort of raft beneath it. At other points, they carried the calf draped over their enormous heads.
“There were several times when the newborn whale was nearly completely out of the water,” the Scientific Reports paper notes. All the members of Unit A participated in the effort to prevent the baby from drowning, but a few—including the calf’s mother and her half sister, Aurora—took leading roles. More surprisingly, the core group also included a member of the second family, Fruit Salad’s granddaughter, Ariel.
“For a long time, there has been this underlying hypothesis that the reason that sperm-whale females live as a family is the need to communally defend and raise a calf,” Shane Gero, who is Project CETI’s lead field biologist and one of the authors of both papers, told me. “But there’s never really been good evidence, scientifically speaking, of something that would count as coöperation, where there’s a cost involved between non-kin that are living together. I think this shows that, during birth events, non-kin coöperate in a way that is both costly and that requires some kind of logging of social behavior, like, You helped me last time, I’ll help you this time.”
Another finding that surprised (and touched) the researchers was that Rounder’s fifteen-year-old half brother, Allan, showed up for the birth. Allan has been separating from Unit A for several years, but, like many a human teen-ager, he seems unsure about whether he’s really ready to live on his own. Allan remained at the periphery of the group during most of the post-delivery activity, but he did eventually get close enough to touch the newborn.
“To me this shows that there’s a lasting bond between these animals—a social memory across time,” Gero said.
Earlier, members of Project CETI found that they could predict when sperm whales were likely to dive based on the sequence of codas they had exchanged. Before, during, and after the birth, the researchers were recording the interactions of Unit A via hydrophones—basically, underwater microphones. They found that the whales’ “vocal style” changed during the birth and also when a group of potentially threatening pilot whales showed up. What the sperm whales were “talking” about, however, remains to be decoded.
“It’s an incredibly complex data set that is filled with all these nuances,” Gruber said. “But that’s kind of good. Because right now we’re still working on the baby slope, but this kind of shows us what the double black diamond is.” ♦