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.