When there's a heat wave, ocean temperatures rise. That heat causes coral reefs (珊瑚礁) to lose their color, which shows the corals are dying. Fish then leave, and without the fish activity, reefs fall silent. A new study finds playing the sounds of a healthy reef can attract fish back to dead or dying areas. Indeed, those sounds could help bring a reef back to life.
Tim Gordon, a biologist at the University of Exeter in England, studies the effect of sound on sea animals. He and his research group “felt surprised at so many different sounds you can hear on a healthy reef”. They were shocked by how quiet the reefs became as they died. That got them wondering: Could sound help renew dying reefs by attracting fish?
So Gordon used pieces of dead coral to create small patches (小块) of reefs along the Great Barrier Reef. He placed them at least 25 meters from each other and from other reefs. Gordon left eleven patches alone. These served as his controls. He set up a loudspeaker around another eleven patches. The speakers played healthy reef sounds. The last eleven patches served as a different type of control. They got a set-up that looked like the loudspeaker but played no sound.
Fish arrived at all three types of patches. But they showed up more quickly at the ones that had sound. Besides, those small reefs ended up with twice as many fish by the end of the experiment. Reefs with sound also had more species overall. Gordon found no difference between the two types of controls. It was sound, not the speaker set-up that had attracted the extra fish. Playing healthy reef sounds adds another powerful tool to restore our reefs, Gordon says.
