"Researchers found that dolphins confronted with noise increase the volume and duration of their calls to one another but struggle to cooperate."
"Mammals in the ocean swim through a world of sound. But in recent decades, humans have been cranking up the volume, blasting waters with noise from shipping, oil and gas exploration and military operations. New research suggests that such anthropogenic noise may make it harder for dolphins to communicate and work together.
When dolphins cooperated on a task in a noisy environment, the animals were not so different from city dwellers on land trying to be heard over a din of jackhammers and ambulance sirens. They yelled, calling louder and longer, researchers reported Thursday in the journal Current Biology. “Even then, there’s a dramatic increase in how often they fail to coordinate,” said Shane Gero, a whale biologist at Carleton University in Ottawa who wasn’t part of the work. The effect of increasing noise was “remarkably clear.”
Scientists worked with a dolphin duo, males named Delta and Reese, at an experimental lagoon at the Dolphin Research Center in the Florida Keys. The pair were trained to swim to different spots in their enclosure and push a button within one second of each other."
Carolyn Wilke reports for the New York Times January 12, 2023.
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