Fish Raise Their Voices to Shout Over Noise

Cyprinella lutrensis, or red shiner, is a cousin of the black shiner. Every day, thousands of cars and trucks rumble across bridges all over the U.S. Their drivers probably don’t give much thought to the fish swimming in the rivers, lakes or bays below. But the fish notice them: They can hear those noisy engines passing overhead, and according to a new study, they are having to shout to communicate over the din. The effects of sonar and other human-made sounds on the communication of marine mammals such as whales and dolphins is well documented. But fish “talk” too – so far, researchers have identified about 800 different species of fish that use vocal signals. One of them is the blacktail shiner, which lives in parts of the Southeast, Midwest and in Texas. Dan Holt, a fisheries biologist at Auburn University in Alabama, wondered how the shiner responds to the ...