Every day, divers capture images of fish living naturally on coral reefs, over sandy bottoms, in kelp forests, estuaries, caves, and the open sea. These photographs are far more than souvenirs or artistic images. Increasingly, they are valuable scientific records, documenting marine biodiversity at a time when aquatic ecosystems are changing rapidly.

Sharks and rays possess a remarkable ability: They can detect the faintest electrical impulses in the water. Hidden in their snouts are tiny sensory organs, called Ampullae of Lorenzini, filled with conductive gel. With them, a shark can sense the heartbeat of a fish buried beneath the sand, or detect the weak signals of prey hidden in darkness.

Even in murky water, even at night, even when prey is perfectly still. The electric field gives it away. It is a form of perception almost unimaginable to us, a way of seeing life itself.

A new study reveals how a team from the University of Victoria, working off the coast of Vancouver Island, has matched specific underwater voices to the species of fish that is making them. This achievement could improve the way we monitor and protect marine life.

A hidden soundscape

The study took place in Barkley Sound, a rich and complex marine environment where rocky reefs teem with life. Over the course of their research, scientists recorded more than 1,000 fish sounds and linked them to eight different species.

Love written in light and sound

Seahorses are famous for one extraordinary fact: the male becomes pregnant. How did it happen that, in seahorses, the roles are reversed? No one knows. 

But this biological wonder is only the beginning. Before mating, pairs perform elaborate, daily courtship dances. They change colour together, entwine tails, and rise through the water in slow spirals. Hidden within these dances are tiny clicking sounds—soft snaps made by rubbing bones in their heads. 

Coral reef fisheries provide essential food and income for millions of people across the tropics. New research shows that most reefs are currently fished below the level that allows maximum sustainable production. 

While this represents a loss of potential food and livelihoods, it also highlights a significant opportunity: rebuilding reef fish stocks can deliver wide-ranging ecological and social benefits.

Scientists have unveiled a breakthrough tool that lets them identify fish by the sounds they make. By pairing spatial audio with 360° video, researchers have published the most extensive collection of fish sounds ever recorded, capturing a chorus that had remained largely unknown until now.

For the first time, scientists have decoded years of underwater “grunts” made by groupers to reveal how and when they spawn. The study, spanning more than a decade of recordings in the Gulf of Mexico and Western Atlantic, shows that fish sounds can provide vital clues for monitoring populations and detecting changes linked to climate and fishing pressure.