Can Coral Restoration Save the Reef?

The Great Barrier Reef is facing a very uncertain future. Global warming is pushing water temperatures up, causing more intense and more frequent mass coral bleaching events.

Reducing global greenhouse gas emissions is the most important action to minimise the impact of climate change on the Reef. Yet the science is clear; warming ocean temperatures are locked in, with emissions reductions too little and probably too late. The Reef now needs our help to survive

We can help through the process of Reef restoration, which is a broad term for methods used to rebuild damaged coral reefs, so they can maintain healthy, sustainable ecosystems. In other words, it’s all the ways we help the Reef to help itself.

There are several reef restoration techniques currently employed.

1. Coral Gardening

Fragments of broken corals are collected and regrown in land-based or underwater nurseries, before being planted onto reefs – much like you would collect and regrow cuttings or seedlings in a pot, before planting them in your garden.

There are numerous coral gardening projects across the Reef, including the Whitsundays.

2. Coral IVF

During mass coral spawning, researchers capture excess coral eggs and sperm from healthy reefs and rear millions of baby corals in specially designed floating pools. These young corals are then placed on damaged reefs, helping to repopulate and restore them. The offspring of these corals will continue to breed, revitalising the damaged reefs.

In the Whitsundays, the Boats4Corals project is helping scale up IVF restoration in the region by harnessing the power of the people. Local tourism operators, Traditional Owners, government agencies, and recreational boaters are being trained in the Coral IVF method; from identification of spawning slicks, to releasing coral larvae from floating nursery pools onto the Reef.

3. Reef rubble

Baby corals need to settle on a clean, stable substrate. Unfortunately, after a bleaching event or cyclone, the substrate is primarily loose rubble, precluding natural recovery.

As such, restoration efforts can also involve stabilisation – using artificial means like mesh netting or carbonate rocks, or replacing damaged or lost reef with new structures, like specially-designed 3D shapes.

4. Helping corals resist warming temperatures

Researchers are investigating the genes of heat-tolerant corals which will give us an understanding of how and where corals might be able to resist warming temperatures. In turn, this will inform us about their potential to adapt to climate change.

It is important to note, the only long-term guarantee for future reefs is to quickly reduce our carbon emissions and reign in global warming. But we are running out of time. However, with effective, large-scale coral restoration, we might just buy the Reef a bit more of time.

Contributed by Whitsunday Conservation Council.

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