AIMS plays frying bacon sounds to fish in bid to save Australia’s coral reefs

To the untrained ear, it might sound like bacon frying in a pan but, to fish, it is the alluring sound of a healthy home.

Marine scientists are using underwater speakers to pump out the sound of a potential breakthrough. 

The Australian Institute of Marine Science (AIMS) is in a race against climate change, with bleaching, cyclones and crown-of-thorns outbreaks threatening reefs.

In response, it has hatched a national project to find out how to make reefs more resilient by studying the World Heritage-listed Ningaloo Reef in Western Australia and the Great Barrier Reef in Queensland.

AIMS biologist Mark Meekan says efforts are focussed on Ningaloo where healthy reef sounds are being played underwater to attract baby fish to reefs, which could improve coral growth.

“If our ears could hear underwater, we’d realise that reefs are actually quite noisy places — lots of pops and crackles from shrimp and all sorts of things,” he said.

“In fact, it sounds a bit like bacon frying in a pan.”

Speakers and spawn

Researchers say reef speakers will eventually be brought to the Keppel Islands in central Queensland to work together with a coral reseeding project.

“We’re going to be deploying some underwater microphones and start measuring and recording the healthy reefs in the very near future,” lead researcher Line Bay said.

It is essential work from the point of view of Woppaburra elder Bob Muir, who is concerned about the future of the reef.

“When it comes to traditional people and Woppaburra, we can’t just move house and go somewhere else,” he said.

“If our land and our reef gets destroyed, that’s the end of our country.”

The Keppel Islands project is examining what factors increase the growth and survival of coral.

Researcher Cathie Page said AIMS had placed laboratory-spawned baby corals onto devices back into Keppel waters.

“The devices have structures that can protect the corals in their early years from predation from fish or overgrowth from algae,” she said.

Ms Page said it was too early to say why, but the results so far were promising, with survivability “much higher than we usually see in the field or in the laboratory”.

Fragile babies

Dr Bay said the corals in the region were fast-growing but very sensitive to damage from storms and bleaching.

“Corals start life as tiny little larva and they grow, they settle onto the reef and then they grow larger, but they’re very fragile in that first year of life,” she said.

“What we’re working with is a fragile, but very important species … we’re really trying to understand how to help them live through these disturbances.”

Dr Bay said controlling carbon emissions and the conditions of reefs were vital, and that this research could be used on a larger scale.

“The vision is that we will seed corals onto the Great Barrier Reef using these methods,” she said.

“We’re hoping we might export some of these solutions to other parts of the world that will also need to use these innovative methods.”