Tiny Baby Corals Could Help Save Earth’s Largest Reef

Nearly half a million baby corals are now taking hold off the coast of Australia, settling in alongside existing coral colonies as part of a massive effort to restore the Great Barrier Reef.

The success of these corals will be a major test for Australia's Reef Restoration and Adaptation Program, which aims to help reefs resist, adapt to and recover from the growing impacts of climate change.

How Does It Work?

Let's rewind to winter of last year, when researchers from the Australian Institute of Marine Science were caring for corals at the National Sea Simulator lab during the annual mass spawning event.

“We have multiple species all spawning at the same time in vast amounts,” explained Christina Langley, a project officer on the program. “It’s the one time where the reef regenerates naturally through sexual reproduction.”
In the wild, only a tiny percentage of those coral larvae survive long enough to settle and grow. Storms, predators, warming waters and algae competition wipe out many before they ever attach to the reef.

That’s where experts are stepping in, collecting the samples and raising them in controlled settings until they settle and start developing healthy polyps and exoskeletons.

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Despite challenges, including rough weather and unexpectedly early coral spawning, teams were able to deploy thousands of newly grown corals across the Northern Great Barrier reefs in January.

It's Not Just Scientists

One of the program’s defining features is the range of people involved in the work, from tourism operators and fishing crews to aquaculture specialists and Indigenous ranger groups with generations of knowledge about the reef.

Researchers with the Australian Institute of Marine Science are training many of those groups to help collect, grow and deploy corals while building long-term reef restoration skills across coastal communities.

Operations coordinator Tim Henry says that collaboration is essential to scaling the work.

“Our traditional owner groups bring their deeper knowledge of country and our industry partners bring their subject matter expertise to our operations, and when we mix that with our scientific knowledge, we get a great positive intervention that we can roll out here at capacity and scale on the reef.”

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What Happens Next

Over the next year, researchers will closely monitor how the newly settled corals survive and grow, paying particular attention to how they respond to environmental stressors.

Early signs are encouraging, but scientists emphasize that this is still experimental work.

Further restoration techniques, including one that works directly with wild coral spawn collected from the ocean, are still being carefully tested and refined to understand what works best at larger scales.

The hope is not to replace natural reef systems, but to strengthen them at a time when climate change is making recovery harder for coral ecosystems around the world.

“We spend so much time taking from the reef,” Langley said. “And now it’s our chance to give back.”

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