If you put a microphone underwater near the oyster reef in North Carolina’s Pamlico Sound, you can hear it: a crisp, crackling noise that sounds like someone just dumped a ton of Rice Krispies into the ocean.
(From Science Daily) — But it isn’t cereal making that noise — it’s thousands of small creatures known as snapping shrimp. Researchers believe that their noisemaking habits could play several key roles within the reef, including serving as an auditory indicator of the underwater ecosystem’s health.
Snapping shrimp are primarily found in reef environments — coral reefs and oyster reefs, like the one in the Pamlico Sound. Only one to two inches in length, the shrimp live on the ocean floor and make their signature sound by rapidly closing the larger of their two asymmetrical claws. They can snap that claw at a speed of about 60 miles per hour. When they do, a giant cavitation bubble, or air bubble, forms. Then water rushes back into the air bubble, generating powerful energy and providing both a weapon for the shrimp and a loud snapping sound.
Read the full article here: https://www.sciencedaily.com/releases/2016/01/160114163041.htm