Scientists Film Dolphins Using Seashells to Catch Fish for the First Time on Australia's East Coast

Researchers from the University of the Sunshine Coast have filmed bottlenose dolphins using an unusual hunting technique called "shelling" in the Great Sandy Marine Park near Hervey Bay, Queensland, marking the first published record of the behaviour on Australia's east coast. In shelling, a dolphin chases a fish into a large empty seashell, carries the shell to the surface, and shakes it so the trapped fish slides into its mouth. Until now, the behaviour had been documented scientifically only in Shark Bay, on the opposite side of the country.

"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," said Dr. Alexis Levengood, an animal behaviourist at the University of the Sunshine Coast who led the study, describing two shelling events her team recorded between July and October 2025.

One encounter, involving an adult female and her calf, may offer insight into how the skill spreads: after the mother's fish escaped and she dropped the shell, "the dolphin calf picked up the shell and held it the same way as its mother," Levengood said. "Our footage provides the first potential evidence of maternal social transmission, a process by which offspring learn behavior by observing the actions of its mother." Researchers also found that a local tour operator, Blue Dolphin Marine Tours, had photographed shelling in the area in 2013 and 2019, suggesting the behaviour went unnoticed by scientists for years due to limited research in the region.

Shark Bay dolphins are also known for carrying marine sponges on their snouts to search the seafloor for prey, a behaviour linked to detecting fish that are hard to find by echolocation. "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," Levengood said.