Swimming in Noise

Marine biologist Heather Spence found her way to the underwater world of sound through her love of music. As a composer and vocalist who also plays viola da gamba, piano, and cello, Spence wanted to understand how sound works, how it manifests across different environments. She pursued a Ph.D. in bioacoustics, and halfway through her studies, came across the snapping shrimp, also sometimes called pistol shrimp: a tiny creature that snaps its one oversized claw so fast it creates a vacuum bubble that bursts with a bang that is one of the loudest sounds in the ocean, audible even above water. “It’s this little critter, the size of your pinky finger, that makes all of this noise,” says Spence.

was enthralled by the outsized anecdotes that accompanied the tiny crustacean. Two decades ago, in order to find what exactly makes the sound, tied seven pistol shrimp to a hydrophone and took 40,000 frames per second with an ultra-high-speed camera. When the shrimp’s air bubble explodes, it releases heat of at least , six times the hottest temperature of lava when it is first ejected from a volcanic vent. The underwater racket of colonies of snapping shrimp interfered with the sonar communication of the United States Navy trying to detect.) For the species, the sound is . They use it to talk to one another, to defend their territory, and to stun their prey (which they then dismember and devour). “I think there’s so much more that we could understand about what’s going on in the ocean if we could really tune in with our ears,” says Spence.