It was a tragic sight. One day last July, a newborn humpback whale calf lay motionless at the bottom of the sea, just a kilometer off Australia’s Gold Coast. The encounter was captured via underwater video. For more than an hour, the mother repeatedly returned to the same spot, gently touching the calf with her head and pectoral fin and resting next to her, face to face. Our new research suggests that this is the first described case of a mother humpback whale caring for her deceased newborn calf. However, they are equally notable for the way they respond to other animals in danger. Humpback whales often defend their calves from orcas. Researchers have also observed them staying with injured or entangled whales, circling them, resting nearby, and trying to help. Humpback whales can even intervene when orcas attack seals, sea lions, and gray whale calves. These care and attention responses are known as epimeletic behavior and are common among cetaceans, a group of marine mammals that includes whales, dolphins, and porpoises. Dolphins and killer whales often stay close to their peers in distress, demonstrating their strong social bonds. These animals can even risk their own lives for the lives of others. This occurred in April off the northwest coast of Scotland, when several pilot whales became stranded after following a female who was giving birth. When a whale loses a calf, orca mothers have been repeatedly observed carrying their dead calves for hours, days, and in rare cases, weeks. The most famous example is that of the Tahlequah orca, which in 2018 carried its dead calf for 17 days over more than 1,500 kilometers. Scientists have observed similar behavior in pilot whales and dolphins. Such lengthy responses illustrate the strength of the bond between mother and calf. Maternal instincts and hormonal changes after birth may contribute to mothers staying with their deceased children. But exactly what animals understand about death is still unknown. Until now, scientists have almost exclusively documented these epimeletic behaviors toward deceased calves in toothed whales. Research on baleen whales, including humpbacks, is scarce. This is probably because dead newborn baleen whales often sink quickly, making such cases extremely difficult to observe. Humpback whale mothers give birth after almost a year of pregnancy and spend the next few months feeding their calves nutrient-rich milk. Immediately after giving birth, mothers often lift their calf to the surface to help it breathe for the first time. During the first months of its life, a calf is completely dependent on its mother for food, protection, and guidance during migration. Tragically, some hatchlings do not survive. This may be due to disease, pollutants, or the mother’s lack of fat reserves that help female whales cope better with pregnancy and better care for their calves. A first for humpback whales Our new study aimed to help fill this research gap. We observed two adult whales off the Gold Coast of northeastern Australia. The two whales remained in the same area for several hours, after what appeared to have been a stillbirth. The female humpback whale released an ammonia membrane shortly after birth, but no placenta was seen. Underwater footage showed the calf resting motionless on the seabed as the alleged mother repeatedly approached her. He remained close to the calf and continued to touch it with his head and pectoral fin. A second adult whale, probably an escort, also remained nearby. The mother humpback did not attempt to lift the calf to the surface of the ocean. This may indicate that he recognized that the calf had died or that he could not remove it from the bottom of the sea. Members of the public reported that two adult humpback whales remained in the area for the next two days. However, our research team could not confirm that they were the same animals. Do whales suffer? To our knowledge, this is the first detailed scientific study of a mother humpback whale caring for her deceased newborn calf. It provides crucial information about how baleen whales cope with death. Could humans ever communicate with whales? – videoMany of the behaviors we observed, including staying close to the calf and suspending normal behaviors such as traveling or socializing with other whales, resemble how other species respond to death. Elephants, great apes, and some species of toothed whales care for their dead calves in similar ways. However, we cannot directly measure the emotional state of the whales. The behaviors we observed could represent grief, but they could also reflect maternal attachment, confusion, or instinctive care. For this reason, researchers use broader terms, such as post-mortem care behavior, rather than concluding that whales suffer in the human sense. However, these behaviors reveal that humpback whales maintain strong maternal bonds even after the death of a calf. Our study suggests that similar cases may have gone unnoticed because scientists rarely observe whale births at sea. One good news is that researchers are increasingly able to observe these animals as whale populations recover and scientific equipment makes at-sea studies more feasible. So while there is much more to learn about whales, their emotional lives may be infinitely more complex than we ever imagined.
