Dolphins Filmed Using Shells to Hunt Fish Off Queensland

Dolphins filmed shelling off Queensland

Dolphins off Queensland, Australia, have been filmed using an infrequently observed hunting method called ‘shelling’ to catch prey.

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

Yet only a small number of people have witnessed dolphins shelling, and fewer still have recorded the behaviour on camera.

Researchers from the University of the Sunshine Coast presented the new footage, recorded at Hervey Bay, 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 previously observed this type of foraging behaviour, although not in this region 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."

Until now, shelling had been formally documented only at Shark Bay in Western Australia, and nowhere else worldwide.

The recordings made by Levengood and her colleagues provide the first visual evidence that dolphins on Australia’s east coast also use this hunting technique.

Watch the video

"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 study also draws on photographic evidence of shelling in the Hervey Bay region, taken by passengers aboard 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

However, the tour boat operators did not recognise the unusual significance of the pictures in their archives until Levengood told them about her observation.

How dolphins use shelling to catch fish

So, what does shelling involve?

While searching for food, dolphins may drive prey, such as a small fish, into a large empty sea-snail shell.

The dolphin then inserts its ‘bottlenose’, or rostrum, into the shell’s opening, rapidly lifts the shell above the surface, and gulps down what has been trapped 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, although their territories 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 by Shark Bay dolphins was published in 2011.

In 2020, researchers examined 42 video observations of dolphins at Shark Bay and found that they might acquire the technique from other members of their pod.

Those observations indicated that dolphins may spread this distinctive foraging behaviour horizontally through their social networks - from peer to peer, so to speak.

Hervey Bay footage suggests mothers teach calves

The new Hervey Bay footage, filmed in 2025, is the first evidence to suggest mothers could be teaching their calves the shelling technique.

The videos recorded 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 the mother or calf managed to eat the fish caught in the shell, but the calf’s participation suggests it may have been learning from its mother.

If shelling is passed from mothers to calves, as well as between pod-mates as seen in 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 further research involving dolphin populations in both Hervey Bay and Shark Bay, to gain a clearer understanding of the subtleties of shelling and how it passes between dolphins.

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 research 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 spot an error, please let us know.