Imagine diving nearly 7 kilometres below the ocean’s surface and finding not one or two whale skeletons, but hundreds of them stretching across the seafloor. That’s exactly what scientists discovered in the Indian Ocean — the world’s largest known whale graveyard.
The extraordinary find, published in the journal Nature, includes nearly 500 whale skeletons scattered along a 1,200-kilometre corridor on the ocean floor west of Australia. Some of the fossils are estimated to be as old as 5.3 million years, making it the deepest and oldest whale graveyard ever discovered.
The whale graveyard was found during a series of deep-sea expeditions carried out by the Chinese submersible ‘Fendouzhe’ in 2023. Researchers conducted 32 dives into the Diamantina Fracture Zone, reaching depths of up to 7,000 metres. What they found left them stunned.
“We were astonished,” lead author Xiaotong Peng of the Chinese Academy of Sciences told AFP.
“It was completely unexpected: the size of distribution, the depth and the age range were far beyond anything we had imagined.”
The team catalogued 485 whale fossils, most belonging to different species of beaked whales. They also identified a previously unknown, now-extinct species of whale among the remains.
When a whale dies, its body sometimes sinks to the seafloor in an event known as a “whale fall.” In the deep ocean, where food is scarce, a whale carcass becomes an enormous source of nourishment. Over time, entire ecosystems can develop around a single skeleton.
The newly discovered graveyard shows this process on an unprecedented scale. From inside the submersible, researchers observed thriving communities of and around the bones, including jellyfish, brittle stars, bone-boring worms, and bivalves.
Many of the animals are believed to be new to science.
Scientists believe the area may have acted like a natural collection point for whale carcasses.
The region is known to be an important feeding ground for whales. In addition, a V-shaped trench on the seafloor may funnel sinking carcasses into the same area over thousands and even millions of years.
Based on the fossil density, researchers estimate there could be more than 10 million whale carcasses spread across the wider Diamantina Zone.
Beyond the sheer scale of the discovery, scientists say the graveyard offers a rare glimpse into how life survives in some of Earth’s most extreme environments.
The soft tissues and fats contained in whale carcasses represent a massive store of carbon and nutrients. According to the researchers, the remains found in the region may represent roughly 6.7 million tonnes of sequestered carbon.
The study also found that some animals living around the whale falls are similar to species found near hydrothermal vents and cold seeps, suggesting whale carcasses may help connect otherwise isolated deep-sea ecosystems.
Researchers believe these underwater “whale cities” could act as evolutionary stepping stones, helping species spread across the deep ocean.
While this is the largest whale graveyard discovered so far, scientists suspect similar hidden bone fields may still be waiting to be found elsewhere in the world’s oceans.
