In 2023, a small crewed submersible called Fendouzhe was exploring a remote underwater valley off the southwest coast of Australia when the pilots spotted something unexpected on the seafloor: whale bones. That first sighting led to 32 separate dives, and what researchers eventually pieced together, published in the journal Nature in June 2026, is the largest and deepest whale graveyard ever found.
The graveyard holds 485 fossilised whale remains spanning 5.3 million years — and it's still growing today.
The site sits in the Diamantina Zone, a fracture in the ocean floor roughly 1,000 kilometres southwest of Perth, formed millions of years ago when Australia and Antarctica pulled apart. Some of the dives reached nearly 7,000 metres down. Across the small area they were able to survey, the team catalogued 485 fossilised whale remains, using strontium-isotope dating to work out their age. The oldest fossil came in at 5.3 million years old, and the site appears to have been quietly accumulating whale remains ever since, right up to the present day.
A Site Still Growing
What makes it more than a fossil bed is that living ecosystems are still forming around the newer remains. Researchers found recent whale falls, meaning carcasses freshly settled onto the seafloor, hosting dense communities of scavengers: bone-eating worms, brittle stars, sea anemones, and tiny amphipods. One whale fall alone was estimated to host close to 2,840 organisms in a single square metre. Among the fossils, scientists also identified a completely new species, now named Pterocetus diamantinae, adding a small piece to the still-patchy fossil record of beaked whales, a group that dives so deep and surfaces so briefly that very little is known about how they actually live.
Researchers aren't yet certain why whales keep ending up in this particular spot, though the leading theory involves the valley's shape: a natural funnel that may draw sinking carcasses in from a wide area, whether the animals died there or simply drifted down from elsewhere.
Image credit: A real deep-sea whale fall community on the seafloor