Study reveals tool use in tropical fish species

A new study published in Coral Reefs on March 26, 2025, has debunked the idea that tool use is exclusive to mammals and birds. Led by Dr. Juliette Tariel-Adam of Macquarie University, the research documented wrasses, a colorful tropical reef fish, using rocks to smash open shellfish for food, providing clear evidence of tool use among fish.

The study observed wrasses intentionally picking up hard-shelled prey, such as crabs and mollusks, and smashing them against rocks to access the food inside. Dr. Juliette Tariel-Adam noted this as evidence of unexpected intelligence in fish. Researchers from Australia, Brazil, and the Caicos Islands documented the first known use of anvils (hard surfaces) by multiple species of Halichoeres wrasses, suggesting that this type of tool use is more widespread among fish than previously believed.

Researchers have documented wrasses using hard surfaces, or "anvils," to break open hard-shelled prey like crabs and mollusks. Through the Fish Tool Use citizen science project, 16 new observations were recorded across five Halichoeres wrasse species. This includes the first evidence of anvil use in three species and the first video evidence for two others, extending the behavior's known range to the western Atlantic. Dr. Juliette Tariel-Adam and Professor Culum Brown emphasized that these findings highlight previously unrecognized tool use among wrasses and contribute to growing evidence of fish intelligence and the evolution of tool use in animals. To learn more, head to Phys Org’s article https://phys.org/news/2025-03-reveals-tool-tropical-fish-species.html#google_vignette