‘Extremely rare' footage captures humpback whale mom grieving her stillborn calf

Rare footage off Australia shows a humpback whale mother repeatedly returning to her stillborn calf on the ocean floor in a heartbreaking discovery.

Rare footage has captured what scientists believe may be a humpback whale mother's response to losing her newborn calf.

According to a study published by Discover Animals, the encounter unfolded off the coast of Australia in July 2025, when observers spotted two adult humpback whales lingering near the surface.

One whale positioned itself vertically in the water with its tail pointed upward. About 30 minutes later, pieces of an amniotic membrane were spotted floating nearby, signaling a recent birth.

Curious about the missing calf, researchers lowered a GoPro camera beneath the surface and discovered a heartbreaking scene on the seafloor. A newborn humpback lay motionless at the bottom of the ocean while the presumed mother repeatedly returned to its side. The whale was filmed swimming alongside the calf, resting next to it, maintaining eye contact, touching the calf and moving a pectoral fin over its body.

Researchers interpreted the event as "postmortem attentive behavior" involving a stillborn calf.

"Reviews suggest that post-mortem attentive behaviour is largely absent or extremely rare among baleen whales, particularly in relation to dead calves," according to a 2018 study, Whale and dolphin behavioral responses to dead conspecifics.

Part of what makes the observation so unusual is the biology of humpback whales. Unlike newborn toothed whales and porpoises, baby humpbacks lack enough blubber to float on their own. Without assistance from an adult, they sink shortly after death, making stillbirths nearly impossible for researchers to observe in the wild.

Researchers watched the mother for nearly two hours and believe the behavior may have continued for hours, or even days, after they left the area.

"Underwater footage documented the mother approaching the calf closely, making repeated contact using her head and pectoral fin, and positioning herself eye-to-eye alongside the corpse," according to the humpback whale post-mortem study.

Notably, the whale did not attempt to lift the calf toward the surface, a behavior documented in some dolphin and toothed whale species after a calf dies. Researchers say this may suggest the mother recognized the newborn was unresponsive, even as she continued returning to it.

Andrew Mulville, a rescue boat captain with the Sea World Foundation and co-author of the study, told Phys.org he initially thought he was simply looking at two whales resting on the surface.

"When I actually worked out what was happening, I was totally surprised," he said. "It was definitely not what I was expecting to see out at sea that day."