Scientists have captured footage of bottlenose dolphins using seashells to catch fish off the Queensland coast, a discovery that sheds light on how the marine mammals learn new tricks.

Researchers at the University of the Sunshine Coast recorded two separate sightings of bottlenose dolphins engaging in the tool-use behaviour, known as “shelling”, in the Great Sandy Marine Park off Hervey Bay between July and October 2025.

“We were on a research boat off Hervey Bay when we spotted a dolphin raising something large out of the water. I started screaming because I know what shelling looks like,” Alexis Levengood, co-author of a new study on the behaviour published in Marine Mammal Science, said. “It’s a hunting behaviour where dolphins chase fish into large empty shells, bring the shells to the surface and then shake them to drain the fish into their mouths.”

“We were able to record footage and take photographs of dolphins shelling in the Great Sandy Marine Park,” Dr Levengood said, “which is the first published record of it on the east coast of Australia.”

An adult female dolphin and its calf were seen shelling together, hinting the calf had learned the skill from its mother. This may be the first potential piece of evidence of “maternal social transmission” in dolphins, the process by which an offspring learns a behaviour by observing its mother, researchers say, adding that it “challenges the belief that dolphins learn this tool use from their peers”.

“These findings highlight how smart, clever and innovative dolphins are,” Dr Levengood said. “We saw the mother surface with a shell, the fish inside escaped, and the dolphin dropped the shell to chase the fish. Minutes afterwards, the dolphin calf picked up the shell and held it the same way as its mother.”

However, scientists caution that more research is needed to understand the finer nuances of shelling.

Previously, shelling had been photographed during boat trips run by the Blue Dolphin Marine Tours in 2013 and 2019, but they were not a part of any published study.

“Our observations in Queensland show that dolphins on opposite sides of Australia have learned to use tools in the exact same way, independent of one another,” Dr Levengood said.

“Better understanding of shelling and other tool use in non-human animals will continue to teach us more about ourselves and how and why we evolved the way we did.”