Researchers have repeatedly filmed a humpback whale mother diving to her stillborn calf on the seafloor, touching it and resting beside its body, in what they say is the first documented case of this behavior in humpback whales. The account was published September 16, 2026, in a study in Discover Animals by Griffith University marine scientist Olaf Meynecke and rescue boat captain Andrew Mulville.

The footage was recorded in July 2025 in waters off Palm Beach on Australia's Gold Coast. The attentive behavior lasted at least 90 minutes, and the mother and a second adult whale remained with the calf for at least two hours before the observers left, according to ABC News Australia and Live Science.

The researchers describe what they saw as "postmortem attentive behavior," sometimes called grieving behavior. The observation adds to a small body of evidence about how large whales respond to death, and it raises new questions about animals that many Americans watch off Hawaii, California, Alaska, and New England.

A Moment Rarely Seen

Mulville, a rescue boat captain with the SeaWorld Foundation, was on a private boat when he was asked to check on two whales reported to be acting strangely. He saw one of them hang vertically with its tail raised, then spotted the remains of an amniotic membrane floating on the surface. The whale had just given birth, but there was no calf in sight.

Mulville filmed underwater and found the calf dead on the seafloor. Meynecke, of Griffith University's Whales and Climate Research Program, told Live Science that the mother kept diving down, swimming beside the calf, resting next to it on the bottom for about a minute, and moving her pectoral fin over its body before surfacing again.

"It is extremely rare to witness," Meynecke said. He noted that only about 20 humpback births have been observed and described in the scientific literature, and none involved a stillborn calf.

Why Dead Humpback Calves Are Rarely Seen

Biology helps explain why this behavior has gone undocumented in humpbacks. Newborn humpbacks do not have enough blubber to float on their own. A calf that dies at birth sinks to the seafloor almost immediately, where it is nearly impossible to spot from a distance.

Toothed whales are different. Orcas and dolphins have been seen carrying or pushing dead calves at the surface, and in one well-known case an orca carried a dead calf for more than a day. The humpback mother in the video did not try to lift her calf to the surface, which the researchers suggest may mean she recognized it had died during birth.

The second adult was an "escort," a companion whale that often accompanies pregnant females and mothers. Based on its size and appearance, the researchers think it was likely a female of similar age, though that was not confirmed. Two adult humpbacks were seen in the area over the following two days, but it is not known whether they were the same animals.

Attachment or Grief

Many headlines have called what the mother did grieving. The researchers are more careful. The study notes that grief is difficult to demonstrate in animals because scientists lack physiological or neurological measurements of what the whale was experiencing.

What the observations do show, Meynecke told ABC, is a clear change in behavior and at least a strong attachment to the calf. The whales were not traveling or socializing but stayed in one spot, milling and turning in the same area.

Vanessa Pirotta, a whale scientist at Macquarie University who was not involved in the study, told ABC that interpreting the behavior is "challenging" and that it is important not to anthropomorphize it, while noting that observations like this are how science learns.

The evidence is a single observation of one mother, recorded opportunistically. It cannot show how common the behavior is, how long it typically lasts, or what drives it. Meynecke said more documentation, possibly with drones, will be needed to understand how humpbacks respond to death and stress.

Lessons for Whale Watchers in U.S. Waters

The study comes from Australia, but humpbacks are a familiar sight off U.S. coasts. Many migrate to Hawaiian waters in winter to give birth and nurse calves, and humpbacks also feed off California, Alaska, and New England.

Meynecke told ABC that understanding how whales respond to loss could help scientists judge how long the effects of stressors such as fishing gear entanglement might last. That makes respectful viewing important, especially near mothers and calves.

In Hawaii, federal rules prohibit approaching a humpback whale within 100 yards by any means, including swimming, paddleboards, kayaks, vessels, and drones, and within 1,000 feet when operating an aircraft, according to the Hawaiian Islands Humpback Whale National Marine Sanctuary. A 100-yard approach limit also applies to humpbacks in Alaska. Hawaii's humpback population is no longer listed as endangered, but the whales remain protected under the Marine Mammal Protection Act. Boaters elsewhere should follow NOAA's boating guidelines and viewing guidance and keep their distance.

Anyone who sees an injured, entangled, or stranded whale should not approach it. In Hawaii, NOAA's Marine Mammal Hotline is 1-888-256-9840. Careful, distant observation is how rare moments like this one get documented without disturbing the animals.

What Readers Want to Know

What did researchers record?

They filmed a humpback whale mother repeatedly diving to her stillborn calf on the seafloor, touching it and resting beside it, off Australia's Gold Coast in July 2025.

Is this the first time this has been seen?

The researchers say it is the first documented case of postmortem attentive behavior in humpback whales. Similar behavior is better known in orcas and dolphins.

Was the whale grieving?

Scientists are cautious. The behavior suggests strong attachment, but grief is hard to prove without physiological or neurological data.

Why are dead humpback calves rarely observed?

Newborn humpbacks lack enough blubber to float, so a calf that dies at birth sinks quickly to the seafloor, where it is hard to see.

How long did the mother stay with the calf?

The attentive behavior lasted at least 90 minutes, and the whales were still with the calf when observers left after about two hours.

How close can people get to humpbacks in U.S. waters?

In Hawaii and Alaska, federal rules prohibit approaching humpback whales within 100 yards. Elsewhere, follow NOAA viewing guidelines and keep a safe distance.