Fish communicate through a form of talking, according to research conducted by University of Massachusetts fish biologists, who found that sounds like grunting, drumming and duck-like calls are all forms of fish communication.
UMass fish biologists Rodney Rountree and Francis Juanes, along with other colleagues at UMass recorded over 24 hours of deep-sea fish noises all over New England, with the bulk of their work conducted from Welkers Canyon.
The researchers worked on local fishing boats and, after several tries, captured fish sounds by putting recording equipment into crab traps. They heard fin, pilot and humpback whales, dolphins and other unidentified sounds from the depths of 2,237 feet.
Fish create their various vocal communications through special “sonic muscles,” used to create the various sounds that all have a different function, according to the researchers. Some sounds are for mating and reproduction, while others use it as a navigation system, which Juanes described as a “sound map.” The sound map is crucial when fish need to travel long distances because they bounce sounds off beaches, to create a “map” of their environment.
Fish have human-like inner ears that can sense sounds between the average ranges of 200-1000 hertz, said the two researchers. The ability for fish to hear though is based on a variety of factors including how loud the fish’s call is, how loud the environmental noises are and how far away the sound is coming from.
“A female [fish] can sometimes distinguish male agility by their voices, making the decision to mate with one, as opposed to the other nearby males,” said Rountree, who added that fish do not talk constantly, because often predators are listening as well.
Human noises in and on the water can interrupt, mask or alter the fish calls and become a threat to the fish, according to the researchers, especially now that fisherman are going deeper into the water to make catches, creating more noise.
Rountree said over the last 40 years that noise pollution has increased, mostly due to the fishing industry as well as motor and various other boats around beaches.
The impact of human noises and noise pollution, according to Rountree, can range from masking fish calls so that a fish may not receive a mating call, to hearing a sonic bomb-like sound. These sounds, Rountree said, “cook the fish on the inside.”
Rountree and Juanes’s study, the first done on deep-sea fish noises in 50 years, was designed not only to educate the public on certain sounds, but to prove there is so much information still unknown about deep-sea fish, they said.
The two fish biologists are working on a new study at the moment, trying to create cameras that can record fish in their habits. However, the task has proven difficult as cameras require light and fish are either attracted to light or repelled by it, making it hard to get a working sample of the fish population, according to the researchers.
Their completed study is the first of its kind, according to the researchers, as it brings to light new ideas on how to study fish, exposing more questions and possible study opportunities.
“If a catalog of fish sounds were gathered, it would allow more researchers to study fish, without killing them, and in their natural environment. It would expose more information about behavior, because virtually nothing is known about them,” Rountree said.
Claire Anderson can be reached at [email protected].
