Chinese researchers map the world's largest deep-sea whale graveyard in the Indian Ocean
Scientists using a submersible discovered a 1,200-km corridor of nearly 500 whale skeletons at depths up to 7,000 m, revealing extensive ecosystems and a new beaked-whale species.
Chinese scientists have identified the deepest and oldest known whale graveyard on the seafloor of the Indian Ocean, spanning a 1,200-kilometre stretch at depths of up to 7,000 metres. The discovery, published in Nature, includes nearly 500 whale skeletons, some dating back 5.3 million years, and a previously unknown species of beaked whale.
The team conducted 32 dives in 2023 with the Fendouzhe submersible, which collected fossil samples using robotic arms. Observations from inside the submersible revealed a variety of deep-sea organisms—jellyfish, brittle stars, bone-boring worms and bivalve molluscs—feeding on the carcasses.
"But discovering a necropolis of this scale was completely unexpected: the size of distribution, the depth and the age range were far beyond anything we had imagined," said lead author Xiaotong Peng of the Chinese Academy of Sciences.
"The vibrant ecosystems we saw offered a completely different perspective on this otherwise dark and cold ocean floor," added co-author Peng Zhou.
Researchers estimate that the area, known as the Diamantina Zone, could contain more than 10 million whale carcasses, sequestering roughly 6.7 million tonnes of carbon in soft tissue and lipids. The study suggests that such whale falls act as evolutionary hotspots and stepping stones for sulfide-dependent fauna, linking communities found at hydrothermal vents and cold seeps.
External experts described the find as significant for understanding whale evolution and deep-sea ecology. University of Hawaii oceanographer Craig Smith called it "extremely exciting," while Florida State University researcher Amy Baco-Taylor said the discovery will likely provide new insights into chemosynthetic communities that were thought to have declined after historic whaling.
The authors note that similar hidden archives may exist elsewhere in the global deep oceans, encouraging further submersible expeditions to locate additional whale graveyards.
