Researchers have captured the first video evidence of dolphins using shells as tools to trap fish, a sophisticated hunting technique observed off the coast of Queensland, Australia. This behavior, known as "shelling," involves dolphins using large, empty seashells to corral their prey.
The study, published in Marine Mammal Science, details how a female Pacific bottlenose dolphin was filmed in 2025 near Hervey Bay using a shell to trap a fish. The dolphin surfaced with the shell, dropped it into the water, and then captured a fish that had been enclosed within it. Alexis Levengood, the study's lead author and a marine mammal biologist at the University of the Sunshine Coast, described the moment as "screaming to the students that were on the boat with me in excitement."
While the behavior was initially observed in 2013 in Shark Bay, Western Australia, this marks the first time it has been recorded on video. The new footage provides concrete evidence of this ingenious method.
Further observations in Hervey Bay revealed a mother and calf engaged in shelling, suggesting the behavior is passed down through generations. In one instance, a mother dolphin surfaced with a shell, and after the fish escaped and the mother dropped the shell, the calf picked it up and held it in a similar manner. This provides the first potential evidence of maternal social transmission of tool use among dolphins.
The findings indicate that dolphin populations separated by thousands of miles have independently developed or learned the same tool-use strategy. Researchers are exploring whether this behavior may be present in other unknown populations.
These discoveries highlight the remarkable intelligence and innovative capabilities of dolphins. The study of shelling and other tool-use behaviors in non-human animals can also offer insights into the evolution of tool use in humans.