Scientists Draw Young Fish To Dying Coral Reefs By Playing Healthy Reef Sounds
Scientists from the UK's Universities of Exeter and Bristol, and Australia's James Cook University and Australian Institute of Marine Science, have found that playing the sounds of healthy coral reefs will draw young fish to reefs that are degrading, according to research published last month in Nature Communications.
“Acoustic enrichment,” as the researchers term it, could be an essential tool in helping to restore damaged coral reefs. “Fish are crucial for coral reefs to function as healthy ecosystems,” Tim Gordon of the University of Exeter said. "Boosting fish populations in this way could help to kick-start natural recovery processes, counteracting the damage we’re seeing on many coral reefs around the world."
The scientists worked on the Great Barrier Reef, where they “placed underwater loudspeakers playing healthy reef recordings in patches of dead coral and found twice as many fish arrived – and stayed – compared to equivalent patches where no sound was played.”
"Healthy coral reefs are remarkably noisy places – the crackle of snapping shrimp and the whoops and grunts of fish combine to form a dazzling biological soundscape. Juvenile fish home in on these sounds when they're looking for a place to settle," said senior author Professor Steve Simpson, also of the University of Exeter.
But as reefs begin their decline, the noise declines as well: "Reefs become ghostly quiet when they are degraded, as the shrimps and fish disappear, but by using loudspeakers to restore this lost soundscape, we can attract young fish back again,” Simpson said.
Though the scientists caution that encouraging young fish to inhabit degrading reefs is not the end-all answer, attracting them is an important piece, because “recovery is underpinned by fish that clean the reef and create space for corals to regrow."
"Whilst attracting more fish won't save coral reefs on its own, new techniques like this give us more tools in the fight to save these precious and vulnerable ecosystems,” Gordon said.