According to a study recently published in the Journal of Mammalogy, researchers have observed behavior resembling grief in seven different cetacean species. The study examined 14 unrelated events in which cetaceans responded to the dead bodies of other whales or dolphins. These were usually those of their own offspring or a close family member.
The seven species included Indo-Pacific bottlenose dolphins, spinner dolphins, killer whales, Australian humpback dolphins, sperm whales, Risso’s dolphins and short-finned pilot whales. Researchers witnessed all of them carrying out what appeared to be vigils for dead pod-mates or relatives. The researchers behind the study were unable to find a scientific explanation for the cetaceans’ behavior. They concluded instead that the animals were exhibiting grief in much the same way that humans might. Study co-author Melissa Reggente says the animals “are mourning…they are in pain and stressed. They know something is wrong.”
Do whales mourn their dead?
Barbara King, emeritus professor of anthropology at the College of William & Mary, is a well-respected authority on the subject of animal grieving and the author of the book How Animals Grieve. Although King warns against anthropomorphizing animal behavior, she has also developed criteria for grief. “Researchers may strongly suspect grief only when certain conditions are met,” she says. This includes examples of animals spending time together beyond survival-driven behaviors. They also include instances when the death of one animal causes the survivor or survivors to alter their normal behavior.
All 14 of the case studies Reggente and her team explored met both these criteria. In one instance, scientists in the Red Sea observed an Indo-Pacific bottlenose dolphin pushing the body of a much smaller dolphin through the water. Even after researchers towed it to shore in order to bury it, the adult dolphin would not leave its side. Instead, she followed the body into shallow water, where she waited for hours after researchers had removed it. Although the scientists have no proof of the dolphins’ kinship, Reggente hypothesizes that they were likely mother and calf.
The relationship between the deceased and the grieving whale were clearer in another example. Off Washington State’s San Juan Island, researchers saw a female killer whale who had just given birth trying to keep the dead calf from sinking by continuously pushing it towards the surface. Co-author Robin Baird thinks that this behavior suggests orcas are capable of human-like grief. This theory is not hard to support when one considers that orca mothers and calves typically have a life-long relationship. In some cases, the whole pod appeared to join in the grieving process. Short-finned pilot whales in the North Atlantic formed a protective circle around a grieving adult and dead calf.
Whales are not alone
This is far from the first time that scientists have observed grieving behavior in animals. In his book Elephant Destiny: Biography of an Endangered Species in Africa, elephant researcher Martin Meredith recorded a phenomenon whereby a herd of wild elephants spent hours touching and trying to lift the body of their dead matriarch. After accepting her death, the elephants covered the body with leaves and tree branches. They then stood over the body in silence for two days. Similarly, legendary primatologist Jane Goodall famously observed the decline of a young chimpanzee named Flint. The animal stopped eating, showed signs of depression, and eventually became sick and died following his mother’s death.
According to Reggente, “the present study helps to corroborate that adults mourning their dead young is a common and globally widespread behavior in long-lived and highly sociable/cohesive species of mammals.” Grieving offers no evolutionary advantage. Doing so takes up valuable time that the animals could use to feed, mate or socialize with living family members. Instead, emotion appears to motivate these actions, rather than the survival instinct.
Knowing that cetaceans can feel grief should have important ramifications when it comes to how we interact with them. At the very least, it lends weight to the arguments that cetacean captivity and global whale and dolphin hunts are morally indefensible.
