Have you ever heard of a fish choir? A single fish might make its own unique noise, but sometimes groups of them overlap and form a fish chorus.
The audio was recorded by Robert McCauley and colleagues at Curtin University in Perth, Australia, in a region outside of Port Hedland over an 18 month period. The team captured the sound using two sea-noise loggers: the first positioned near the Port Hedland shore and the second 21.5 kilometres away in offshore waters.
Fish make sounds for many different reasons. Nocturnal predatory fish use calls to stay together to hunt, while fish that are active during the day use sound to defend their territory. “You get the dusk and dawn choruses like you would with the birds in the forest,” says Steve Simpson, a marine biologist at the University of Exeter, UK.
“I’ve been listening to fish squawks, burble and pops for nearly 30 years now, and they still amaze me with their variety,” says McCauley, who led the research.
“We are only just beginning to appreciate the complexity involved and still have only a crude idea of what is going on in the undersea acoustic environment,” says McCauley.