Fish are widely believed to be silent creatures but new evidence suggests that certain species of fish sing together in the sea. Just like birds, these marine animals make chorus everyday at dawn and dusk.
In a new study published in the journal Bioacoustics on Sept. 3, Robert McCauley, from Curtin University in Perth, Australia, and colleagues used sea-noise loggers placed at different points off the coast of Port Hedland in Western Australia and recorded distinct choruses in the ocean occurring at different times of the days especially at dawn and dusk.
Songs were predominantly heard early spring and late summer, and majority of the underwater soundscape was produced by repetitive solo calls from fish. Once the sounds of different fish overlap though, the calls form choruses.
"Distinct diurnal patterns in the choruses were observed, associated with sunrise or sunset and in some cases, both," the researchers wrote in their study.
"Some pairs of choruses present on the same day exhibited various combinations of temporal and frequency partitioning, while others displayed predominant overlap in both spaces."
Although fishes have long been considered as silent creatures and seem to be unlike noisy birds and mammals, it actually makes sense that these marine creatures vocalize just like other animals.
In nature, producing sound can be used as an effective means of getting attention. Frogs, for instance, croak when searching for mates, prairie dogs use a complex series of "yips" when they alert each other of potential danger and young birds produce sound to show how hungry they are.
Sound also has important role in a number of fish behaviors such as territorial disputes, reproduction and feeding. Nocturnal predatory fish, for instance, use calls so they all stay together when they hunt. Fish that hunt during the day also use sound to defend their territory.
Birds are known to sing louder in areas with more sound pollution such as in cities so their prospective mates can hear them amidst all the urbanization.
For their research, McCauley and colleagues did not find evidence that the fishes in the area of their study were affected by sound pollution. Nonetheless, this may not be the case elsewhere as earlier studies have found evidence that the ocean has become too noisy for other marine animals such as whales and dolphins.
Ocean noise can have detrimental consequences to marine animals. Ship noises, for example, hinder the ability of endangered whales to hear each other.