Coral reefs are noisy places —or rather, they’re noisy when they’re healthy. But because of climate change and pollution, these ecosystems are dying. And in the process, they’re getting quieter and quieter. Now, researchers are trying to broadcast the sounds of healthy reefs underwater to lure fish back to degraded ones in hopes of rebuilding them. Marine biologist Steve Simpson at the University of Exeter talks to host Marco Werman about the research.