Coral reef remediation can affect well-being of planet

As medical officer for another leg of the Polynesian Voyaging Society’s around the world voyage with Hokulea, I recently had the opportunity to dive the Great Barrier Reef off the East Coast of Australia. The reef has suffered immensely from increased water temperature and ocean acidification due to climate change. However, according to professor Ruth Gates, marine biologist at the University of Hawaii, cutting-edge research on corals could one day be part of the solution that reverses global warming.

The Great Barrier Reef is one of the largest living ecosystems on the planet. It is visible from space and is listed by UNESCO as a World Heritage site. It is also one of the highest value natural assets in the world, according to Gates. Why? It is home to such abundant biodiversity and generates protein for millions of people. In fact, 70 percent of the protein consumed in the Pacific Rim depends on reef life. The world’s reefs also provide critical mechanical barriers that prevent shore erosion, and they are a platform for tourism, with human services valued at approximately $30 billion annually.

Corals are a highly sensitive and complex form of life made up of tiny animal polyps living in symbiosis with unicellular algae and a range of bacteria. The algae typically live inside coral polyp cells, and use energy from the sun to make nutrients that feed the polyps. The mutually beneficial cohabitation of these three types of organism, sometimes called a "symbiome," is easily disrupted.

The opportunity to dive the Great Barrier Reef with Gates enabled me to not only delight in this unbelievably awesome coral underworld but also to understand the science behind what we saw and its critical relevance to the health of the planet. As President of the International Society for Reef Studies and an accomplished martial artist, Gates is an authority who does not pull her punches.

The solution to global warming, she explains, begins by reducing the global carbon footprint and transitioning from all types of fossil fuels toward renewable energy sources, such as solar, wind, hydropower and geothermal. It also calls for a concerted effort to minimize our collective energy requirements.

In addition to reducing causative agents and curtailing energy consumption, the world’s coral reefs must be remediated. Typical evolutionary change involves natural selection for those corals that are better able to withstand temperature and acidity. Eventually, this results in DNA sequence changes as the corals adapt. It works but takes much too long given the current rate of global warming.

A far quicker method of supporting coral to adapt is the subject of Gates’ work. If corals survive a stressful event, their experience can make them better able to withstand a second stressful environment. This results in switching on existing genes. These stressful environments can be created artificially in the lab and train corals to remember stress. This is similar to when you train for a marathon. It is hard to do initially, but you get there. The next year it is not so hard to become marathon ready because your muscles retain some memory.

In the natural setting, some corals are able to withstand higher temperatures or more acidity than others. Call them "super performers." Now bring them into a lab and expose them to warmer and more acidic waters — conditions of the future — train them to withstand the stress. Then breed them, with other super performers, and create stocks of corals that are pre-adapted to future ocean conditions.

This method does not involve creating genetically modified organisms. It simply "assists evolution" and accelerates natural processes to generate corals that are most fit to survive the future. These new corals can then can be planted on reefs to restore them.

Say an important reef has been destroyed. Was the compromised reef a source of important fisheries for food stock or was its principal value to protect coastal lands and a vulnerable human population? Perhaps the damaged reef was the mainstay of an economy based on tourism.

Whether remediating a reef to ensure a food supply, afford protection from the elements or stabilize an economy, the return of healthy corals throughout the planet will serve to fix carbon from the atmosphere, reduce greenhouse gases and has the potential to play a role in reversing climate change.

One major question is how quickly and effectively this strategy could be scaled up once proof of concept is complete. Because corals are colonial animals, a single individual can be fragmented to make many individuals, and these stocks may be used to seed a large reef area, said Gates.

Malama Honua, the mission of the Polynesian Voyaging Society’s around the world voyage, is about stewardship of our blue planet. The Great Barrier Reef is one of her lungs upon which our own lungs depend.

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Ira “Kawika” Zunin, MD, MPH, MBA, is a practicing physician. He is medical director of Manakai O Malama Integrative Healthcare Group and Rehabilitation Center and CEO of Global Advisory Services Inc. Please submit your questions to info@manakaiomalama.com.