A new and rare encounter suggests baleen whales may mourn their dead

Scientists had a rare view of what could be humpback whale mourning when they spotted a female attending the body of a dead calf.

The sighting suggests that baleen whales may experience grief, marine biologist Olaf Meynecke and rescue boat captain Andrew Mulville report September 16 in Discover Animals.

Some toothed whales, such as orcas, have been seen spending long periods with dead calves,  occasionally carrying them at the surface for days. Such demonstrations of apparent grief are rarely seen in baleen whales. This may be because newborn baleen whales are born without the fat stores that would cause a whale corpse to float. If mothers spend time with dead calves on the seafloor, there’s a very low chance humans would see the interaction. The authors believe this is the first detailed documentation of a humpback attending to a calf after its death.

In July 2025, Mulville, who works for the Australian marine animal rescue group Sea World Foundation, saw two adult humpback whales (Megaptera novaeangliae) in the water off Palm Beach in Queensland, Australia, and went to check on them. As he approached, he saw some tissue floating on the surface that looked like amniotic membrane — the placental lining that whales shed into the water at birth.

On the seafloor, he could see a small newborn calf, less than four meters long. The female “ended up diving down, making eye contact and actually putting her pectoral fin — her arm — over the stillborn and resting next to it,” says Meynecke, from Griffith University in Brisbane, Australia.

Two adult whales, which the researchers believe were the calf’s mother and her male escort, were seen in the same area for two more days. “We can’t prove it, but I’m very certain they were the same whales, which also suggests that this is a prolonged change of behavior … something that we might call mourning or a form of grieving,” he says.

“It was pretty emotional to observe,” says Meynecke, but he warns against anthropomorphizing and drawing parallels to humans. Remember that “the whale is experiencing their world in a completely different form and shape,” he says. “They have different ways of understanding their environment.”