Fishing For Compliments: ‘Talking’ Fish Chatter About Food And Sex

Swimmers and divers should not be surprised to find that some fish may be “talking” underwater, according to a new study on fish sounds.

Researchers at Cornell University, who published their research in the journal Ichthyology & Herpetology, say that fish are more likely to use sound to communicate than previously thought. In fact, the scientists say some species have done so for 155 million years.

“We’ve known for a long time that some fish make sounds,” said lead author Aaron Rice of Cornell. “But fish sounds were always perceived as rare oddities. We wanted to know if these were one-offs or if there was a broader pattern for acoustic communication in fishes.”

The team looked at ray-finned fish — so called because their webbed fins are supported by bony spines, or rays — which comprise 99 percent of known fish species. They found 175 families of fish in the ray-finned family tree that together contain two-thirds of the fish species that are known to, or likely to, communicate with sound.

The authors found that sound evolved at least 33 separate times over the course of millions of years, an indication of its high importance.

“Thanks to decades of basic research on the evolutionary relationships of fishes, we can now explore many questions about how different functions and behaviors evolved in the approximately 35,000 known species of fishes,” said study co-author William Bemis of Cornell. Having abandoned a “strictly human-centric way of thinking,” Bemis said, “what we learn could give us some insight on the drivers of sound communication and how it continues to evolve.”

The sources of information for the study include extant scientific papers and recordings of fish sounds, references in literature from before the advent of underwater recordings, and the anatomy of the fish, including whether they have the right sound-generating organs, such as an air bladder, sound-specific muscles and specific bones.

“Sound communication is often overlooked within fishes, yet they make up more than half of all living vertebrate species,” said co-author Andrew Bass, also of Cornell, noting that studies of underwater communication have focused on cetaceans, such as whales and dolphins. Bass said that fish have been overlooked “because [they] are not easily heard or seen… But fishes have voices too.”

Rice said fish communicate among themselves about more or less the same things humans do: sex and food. When fish seek a mate, communicate their location or defend a territory, they make themselves known. He said that many fish bear names alluding to the sounds they make, such as grunts, croakers, trumpeters, squeaking catfish and hog fish.

For his part, Rice will continue tracking new sounds discovered among fish and add them to his database. “This introduces sound communication to so many more groups than we ever thought,” said Rice. “Fish do everything. They breathe air, they fly, they eat anything and everything — at this point, nothing would surprise me about fishes and the sounds that they can make.”

Edited by Siân Speakman and Kristen Butler