You’ve probably dived among thousands of reefs and been amazed by their colors, shapes, and inhabitants… but… have you ever stopped to listen to them?
Although many people don’t know it, the ocean is much noisier than we think. Beyond the sounds humans make in the water, many other animals also emit sounds in the reefs. Can you guess which ones?
The Fish That Make the Most Sounds
In fact, it’s not just one or two species. From the smallest invertebrates to over 800 species of fish, many animals produce sounds of different frequencies, intensities, and forms.
For example, some of the noisiest fish are damselfish, which create sounds using vibrations of their swim bladder. Each sound has a different meaning: from squeaks and clicks used to scare off intruders, to pulsing sounds males make during courtship.
Other fish produce different sounds too. For instance, parrotfish make noise by biting coral with their beaks — and this sound can even be heard by divers!
Soldierfish produce grunt-like sounds, the triggerfish creates noise by striking, and some studies have even recognized laughter-like sounds.
Whether made by the swim bladder, throat, or teeth, all these sounds form an underwater concert — one that often intensifies at night. That’s when the noise can reach up to 35dB, the same volume as a quiet conversation!
Are Fish the Only Ones Making Sounds?
Not even close!
The most characteristic sound of the reefs — that “crick-crick-crick” noise mixed with the water — is produced by shrimp, prawns, lobsters, crabs, and other animals that snap their claws.
But that’s not all. Lobsters, like the common Palinurus elephas, also produce sounds by moving their antennae. Some even use these sounds as a defense mechanism against predators.
Other invertebrates, like sea urchins and cuttlefish, have also been shown to produce sounds — though we still don’t know exactly how. From the crackle of shrimp to the choruses of fish, each sound has a purpose and a role in the ecosystem.
As we’ve seen, most species use these sounds both to scare off predators and attract mates.
But that’s not their only function: beyond communication and interaction, reef sounds are key to attracting fish larvae. When born, these larvae are released into the open ocean — and guided by the reef sounds, they can find a community to settle in. So, the more sound a coral reef makes, the more larvae it will attract.
This also ties into something we mentioned a few weeks ago…
Surely you remember the post about marine ecosystems and the importance of biodiversity. We know that the more species and the greater the number of organisms in a reef, the more resilient it will be. That’s why, the louder a reef sounds — like it’s singing — the more species it likely hosts, and the healthier and stronger that reef is. Still, there’s much to discover, many sounds to study, and many species yet to be known.
And you — have you ever heard any of these species? If not, we’ll take you there:
Best Places to Hear Singing Corals
Places with high biodiversity and ideal diving conditions are your best bet to explore these singing coral reefs. And of course, if we’re talking coral, we must talk about the Coral Triangle:
Sipadan:
Malaysia’s Sipadan Island, located off the north of Borneo, is an untouched masterpiece, as Jacques Cousteau once described it. Located in the heart of the Pacific’s Coral Triangle, this volcanic island features walls that drop 600 meters deep.
As a marine reserve, diving in Sipadan is known for having some of the clearest waters in the world — sometimes reaching 60 meters of visibility. Its perfect climate, hundreds of coral species, and over 300 species of fish make it one of the most sought-after dive sites in Asia.
Raja Ampat:
Known as one of the world’s top dive spots, the Indonesian archipelago of Raja Ampat is every diver’s dream. This group of tiny islands is hard to reach.
Perhaps because of its remoteness and protection, it boasts one of the highest biodiversities on Earth, with many comparing it to “pristine” seas — those untouched by humans. Diving in Raja Ampat, you’ll find all kinds of hard and soft corals, crystal-clear waters, and postcard-worthy landscapes.
Palau:
Perhaps the least-known and least-explored site on this list — but no less impressive. We’ll take you diving in this island-state, and trust us, you won’t regret it.
Diving in Palau feels like swimming in a diver-proof pool, full of coral walls, clear waters, massive schools of fish like you’ve never seen, and yes, plenty of sharks. That’s why we call it a diver’s paradise.
As we immerse ourselves in these sounds, we not only appreciate marine biodiversity, but also understand the importance of conserving these ecosystems.
A noisy, singing reef is a sign of a healthy and biodiverse ecosystem, while a silent reef may signal degradation. That’s why it’s crucial to promote conservation practices that protect these sonic habitats — such as reducing noise pollution and establishing marine protected areas.
