Dec 2 2019
Image Credit: Irina Markova/ Shutterstock.com
Around a quarter of the world’s coral reefs are, at this point, damaged beyond repair, and a huge two-thirds more are considered to be in danger of perishing. For many years scientists and environmental agencies have warned of the threats posed to these natural habits from climate change, destructive fishing practices, tourism, pollution, sedimentation and coral mining.
Recent reports on the Great Barrier Reef have elevated the severity and urgency of the situation, following the hot summer of 2016 warm water blanketed the corals in this reef causing “an unprecedented bleaching event” which results in half the reef’s coral dying. While the outlook for this special ecosystem has seemed very bleak, a new study has recently reported findings that bring hope to the situation.
Sounds Of A Healthy Reef Lure In Fish
Published this month in the journal Nature, a revolutionary study sees a team of British and Australian researchers outlining a strategy that they believe will have a significant impact on restoration efforts. The idea is simple; they propose to broadcast the sounds of healthy reefs in dying ones to attract diverse communities of fish back to the dying ecosystem.
The team implemented this method during a six-week field experiment, where researchers played audio recordings taken from healthy reefs from underwater loudspeakers strategically placed in areas of dead coral in Australia's Great Barrier Reef.
The results were promising, the team reported that twice as many fish had been attracted to the areas where sounds were being played, in comparison to the dead patches where no speakers were placed, demonstrating the effectivity of their method in luring back wildlife to the area.
Healthy Coral Reefs Are A Noisy Place
A healthy coral reef is full of bustling life, a biological soundscape of animals that are supported by the reef who make a lot of noise in their daily comings and goings. A dying reef, on the other hand, is a quiet place, which becomes quieter still as animals continue to flee the area. Recognition that healthy reefs are noisy places is what inspired this study.
The sounds they played in the previously desolate areas became full of life once more, with the sounds increasing the number of species present by 50%. What’s more, the sounds drew in animals from all over the food web, like scavengers, herbivores, and predatory fish, showing that the technique on its own has the potential to restore the entire breadth of the lost biodiversity.
Fish Are The First Step To Reversing Coral Reef Damage
Potentially, the method could be replicated at large scales, and if successful it could establish itself as an essential tool to reverse the significant damage that has been done to the world’s coral reefs. Already, scientists are concerned that conservation efforts are not enough to counteract the effects of climate change, therefore, the development of reliable new methods for bringing back biodiversity to dead reefs is essential to address future damage as well as damage that has already occurred.
Bleaching events just like that which killed off half the Great Barrier Reef’s coral in 2016 are happening four times as often as they did just 30 years ago. With such detrimental environmental events occurring at an increasing frequency, new and effective strategies such as this one which uses the simple technique of sound will prove invaluable to the future of reef conservation.
While bringing fish back to dead reef areas is not sufficient on its own to completely reverse the damage, attracting these fish populations is instrumental in aiding the recovery of the coral which relies on established and diverse populations of fish in numerous ways. The sound system could be the first crucial step towards recreating the lost coral reef systems around the world.