Marine scientists have finally filmed something rare. Dolphins recorded using sea shells to trap and eat fish have now been documented on Australia’s east coast for the first time. This clever hunting trick, known as “shelling,” was once thought to happen in only one place on Earth. Now, researchers believe many more dolphin groups could be using it quietly, without anyone noticing.
What Is “Shelling” and How Does It Work?
Shelling is a smart hunting method. First, a dolphin chases a fish into a large, empty sea snail shell lying on the ocean floor. Then, it lifts the shell all the way to the surface. Finally, it tips the shell upside down and shakes it, so the trapped fish slides straight into its mouth.
It sounds simple. However, it takes real skill, timing, and memory to pull off again and again.
A Rare Sighting in Hervey Bay, Australia
Researchers from the University of the Sunshine Coast were surveying dolphins in Queensland’s Great Sandy Marine Park when they spotted something unusual. A dolphin was lifting a large object out of the water near their boat.
“I started screaming because I know what shelling looks like,” said Dr Alexis Levengood, an animal behaviourist and the study’s lead author.
Between July and October 2025, the team confirmed two adult female dolphins performing the behaviour. As a result, their footage became the first published, filmed evidence of shelling anywhere on Australia’s east coast.
Local Boat Operators Spotted It Years Earlier
Interestingly, the behaviour wasn’t actually new to the area. Local tour operators had reportedly seen dolphins shelling as far back as 2013 and again in 2019. Still, without dedicated research in the region, nobody could confirm or record it scientifically. This shows how much marine behaviour likely goes undocumented simply because so few people are watching closely enough.
Mothers May Be Teaching This Skill to Their Calves
Perhaps the most exciting part of the discovery came in October 2025. The team’s cameras captured a mother dolphin appearing to demonstrate shelling while her calf watched closely nearby. This footage offers the first possible evidence that shelling is passed down from mother to calf, rather than only learned between friends.
How This Changes What We Know About Dolphin Learning?
Before this, scientists mostly believed dolphins picked up shelling through peer learning, meaning they copied friends and other dolphins in their social circle rather than their own mothers. A well-known 2020 study of Shark Bay dolphins in Western Australia, for example, found that shelling spread mainly through social networks of unrelated adults, similar to how chimpanzees share foraging tricks.
“Our footage challenges the belief that dolphins learn this tool strictly from their peers,” Dr Levengood explained.
That said, other experts note both ideas can be true at once. Janet Mann, a dolphin researcher at Georgetown University, has pointed out that calves spend tens of thousands of hours beside their mothers early in life. Therefore, some mix of maternal teaching and peer influence likely shapes the final skill.
Not the First Time Dolphins Have Used Tools
Dolphins already had a reputation as one of the ocean’s smartest problem-solvers, and this discovery only adds to it.
| Tool-Use Behaviour | Location | Purpose |
| Shelling (sea shells) | Shark Bay, WA & Hervey Bay, QLD | Trapping and draining fish into the mouth |
| Sponging (basket sponges) | Shark Bay, Western Australia | Protecting the beak while foraging in rubble |
| Bubble-net feeding | Alaska (humpback whales) | Rounding up fish schools |
| Twig hooks | New Caledonia (crows) | Extracting larvae from tree crevices |
Sponge-Wearing Dolphins of Shark Bay
In Western Australia, some dolphins wear bowl-shaped basket sponges over their beaks like protective gloves. This lets them dig through sharp coral and rocky rubble on the seafloor without hurting themselves while hunting. Scientists first documented this “sponging” behaviour back in 1997, and it remains one of the clearest examples of tool use outside primates.
Why This Discovery Matters for Ocean Science?
This finding matters for a few reasons. Firstly, it proves that shelling isn’t limited to one isolated dolphin population. Secondly, it suggests that dolphins living more than 3,000 kilometres apart developed the same complex behaviour, likely without ever meeting. Consequently, researchers now wonder whether shelling, and other tool-use tricks, might simply be going unnoticed in dolphin populations around the world.
Moreover, the discovery adds fresh weight to the idea that dolphins have culture. In other words, they don’t just survive on instinct alone; instead, they teach, learn, and pass down knowledge across generations, much like humans and great apes do.
What Happens Next?
Dr Levengood and her team plan to keep studying the Hervey Bay dolphins to learn more. In particular, they want to understand how widespread shelling really is, how it evolved, and how deeply maternal teaching shapes it compared to peer learning.
For now, though, one thing is certain: dolphins recorded using sea shells to catch fish have shown, once again, just how resourceful, patient, and intelligent these marine mammals truly are.
