Do fish talk?

Animal bioacoustics takes in a lot of territory. Every animal makes some form of sound – either intentional or unintentional. But, in our case, we would like to concentrate on marine bio-acoustics.

Marine bioacoustics itself is a wide ranging field. The most work has centered around marine mammals – whales and dolphins. But in the past few years the field has expanded to include fish sounds – yes, fish do indeed make sounds! And, snapping shrimp and virtually every other living creature in the marine environment.

It’s estimated that perhaps half of all fish species make sound. These are called soniferous fish. I know fishermen who swear ‘the fish were laughing at us’. But, researchers around the world are just beginning to unravel the mysteries of fish sounds.

Using hydrophones (underwater microphones), researchers ‘hunt’ for sounds – identify them – and watch for telltale signs of spawning activity. Much of the sound has to do with attracting mates. The male generates a sound by vibrating his swim bladder to advertise his presence. And, perhaps, to warn off other males.

Tracking fish by their sounds lets researchers identify spawning sites. They have found that each species of fish makes different sounds. So, by listening to the sounds you can find a spawning area, identify which fish are there and even estimate their number.

If it turns out (as is likely) that fish return to the same spawning spots year after year, these areas can be protected by law. The sounds fish make vary by species.

It seems easy, but it’s not. You have to identify which sounds are made by what fish. In any body of water that can be difficult. The sea, or even a pond, can be a very noise place – underwater that is.

You will hear ‘grunts’, ‘drums’, ‘doorknocks’, ‘heartbeats’ , ‘burps’, ‘croaks’, ‘crackles’, ‘chattering’, ‘purring’, ‘clucking’ and even a ‘foghorn’!

For samples of these and other sounds, check out our LISTEN page.