Dolphins Filmed Using Shells to Hunt Fish, Offering New Evidence The Behaviour Might Run in The Family

Dolphins filmed off Queensland, Australia, have been seen using a seldom-observed hunting method called ‘shelling’ to catch prey.

Indo-Pacific bottlenose dolphins (Tursiops aduncus), called ‘buthu’ in the Indigenous Butchulla language, are highly intelligent animals recognised for using tools.

Although dolphins are known to use this method, very few people have watched shelling happen, much less recorded it on camera.

Researchers from the University of the Sunshine Coast presented the new Hervey Bay footage in a study published in Marine Mammal Biology.

"We were out doing our normal dolphin surveys… looking at dolphins, looking to record behavior, where they are, what they're doing, and also their health," behavioural ecologist Alexis Levengood told ScienceAlert.

"We were observing a dolphin, and we saw her, all of a sudden, lift this shell out of the water."

Levengood is among the fortunate few to have observed this sort of foraging previously, although not elsewhere in this part of Australia.

"The second I saw that shell in the air, I immediately knew what was happening." Levengood said.

"I was screaming to the students that were on the boat with me in excitement, because I was just so excited that we were actually witnessing this here on the east coast."

Shelling dolphins filmed at Hervey Bay

Before these observations, shelling had been formally recorded only at Shark Bay in Western Australia, and nowhere else worldwide.

The videos gathered by Levengood and her colleagues provide the first visual proof that dolphins along Australia’s east coast use this hunting technique too.

"They may have both invented this or innovated this independently of one another, or it's even possible that there might be some populations up north that are doing this that we don't even know about yet," Levengood said.

The research additionally contains photographs of shelling near Hervey Bay, taken by passengers on the Blue Dolphin Marine Tour in 2013 and 2019.

"I was screaming to the students that were on the boat with me in excitement, because I was just so excited that we were actually witnessing this here on the east coast."

Marine mammal expert Alexis Levengood

It was only when Levengood told the tour-boat operators about her own observation that they recognised the significance of the rare pictures that had long been in their photographic archives.

How dolphin shelling works

So what, exactly, does shelling involve?

While searching for food, dolphins may drive prey - perhaps a small fish - into a large, vacant sea-snail shell.

The dolphin then inserts its ‘bottlenose’, or rostrum, into the shell opening, swiftly lifts the shell out of the water, and swallows the contents held inside.

"We know they don't all do it. It takes some skill, it takes some knowledge of where to find these empty shells, how to maneuver those shells, and how to be successful in getting the fish out," Levengood explained.

Indo-Pacific dolphins do not migrate, though their ranges do overlap.

"All it takes is one dolphin doing something clever that is easily learnable for it to spread," Levengood said.

The first scientific account of shelling in Shark Bay dolphins was published in 2011.

In 2020, scientists examined 42 video observations of Shark Bay dolphins and found they may acquire the technique from other members of their pod.

Those observations indicated that dolphins could spread this distinctive foraging behaviour horizontally through their social network - from peer to peer, in other words.

Dolphin calves may learn shelling from their mothers

Fresh footage from Hervey Bay, recorded in 2025, offers the first evidence that mothers could be passing the shelling technique on to their calves.

The recordings documented an adult female and her calf shelling alongside one another.

"We saw a mom shell first, pick up the shell and drain the fish… and you can actually see in our drone footage, the fish escapes the shell, and the mom chases the fish down," Levengood said.

"Within minutes of dropping her shell, her calf picked up the shell and was doing the same thing."

Levengood does not know whether either the mother or calf managed to eat the fish caught in the shell, but the calf’s participation suggests that it may have been learning from its mother.

If calves can inherit shelling from their mothers, in addition to dolphins learning it from pod-mates as at Shark Bay, "it suggests to us there might be an element we've overlooked," Levengood said.

"There might be more than one avenue in which they learn this."

The team hopes to undertake more research on dolphin populations in both Hervey Bay and Shark Bay, to gain a clearer understanding of the subtleties of shelling and how dolphins pass the practice between one another.

Related: Sponge Foraging in Dolphins Does Something Unique to Their Genes

"Hopefully with time, and more eyes on the water, and more awareness of this behavior, people might start seeing it if it is occurring in other places," Levengood said.

The study was published in Marine Mammal Science.

This article was fact-checked and edited by Clare Watson. Although we take pride in our process, we are only human. If you notice an error, please let us know.