For scientists working to reverse the threats posed by climate change and environmental damage to the oceans, coral reefs are in trouble, but a solution to this may be, the "music of marine life" that helps subsist the ecosystem.
An international team of scientists wanted to know whether replacing the sounds of a healthy coral reef would attract fish to dying areas of the reef. It turns out that "reef music" worked to attract and hold fish to aid natural recovery.
“Healthy coral reefs are remarkably noisy places - the crunch of shrimp and the cries of fish combine to form a dazzling biological soundscape,” explains Dr Steve Simpson of the University of Exeter in the UK. "Juvenile fish focus on these sounds when looking for a place to settle."
The problem is that damaged reefs become ghostly silent and the delicate food web drifts away from them. Different groups of fish provide different functions on coral reefs and the loss of biodiversity is important.
So the team went to work on "acoustic enrichment." Simpson, along with researchers from Australia's James Cook University and the Australian Institute of Marine Sciences, as well as the University of Bristol in the United Kingdom, published their findings in the journal Nature Communications on Friday last week.
They simply set up underwater speakers that played recordings of healthy reef sounds on selected patches of dead coral for 40 nights, as "fish settlement" is primarily a nocturnal behavior. The chosen area, near the Lizard Island Research Station in Australia, had seen two previous years of bleaching damage affecting around 60 percent of living corals.
By creating the sounds of reef life, the scientists doubled the number of fish that reached the experimental sites and increased the biodiversity of the species at those sites by 50 percent.
"Maintaining healthy fish communities counteracts reef degradation, but degraded reefs smell and sound less attractive to settlement-stage fish than their healthy states," the document explains. While the focus was on populations of common damselflies, they also noticed other marine life foraging for food, and they are sure it was sound rather than other visual cues or the speaker structures themselves.
Australian researcher Dr. Mark Meekan cautions that obviously the fish are being returned to a dead reef and will not automatically come back to life, but "recovery is based on fish cleaning the reef and creating space for the coral to grow back. ”.
The study did not compare the sounds of "reef music" to see which works best, nor did the scientists suggest that artificial sound could do the job itself. They see their discovery as another tool that can be used in conjunction with active restoration techniques and conservation measures.