Saving coral reefs: A global mission

Coral reefs occupy less than 1% of the ocean floor but are home to more than 25% of marine life, according to the United Nations Environment Programme. They also feed local communities, delight tourists and act as natural barriers against coastal erosion and storm damage. But coral reefs are under threat from rising sea temperatures, ocean acidification, pollution, overfishing and destructive fishing practices.

Thankfully, the U.S. and partner nations and organizations are deploying techniques like reinforced steel, hungry sea urchins, artificial intelligence (AI), and electrical currents to save the world’s coral reefs.

Coral reefs under threat

Corals will bleach and die if ocean temperatures rise and stay elevated for extended periods “even by as little as 1–2 degrees Celsius,” explains Derek Manzello, coordinator of the National Oceanic and Atmospheric Administration ‘s (NOAA) Coral Reef Watch .

Pollution from agriculture, sewage and industrial activities also introduces harmful substances that can cause diseases and algal blooms, smothering coral reefs. Overfishing and destructive practices such as blast and cyanide fishing further damage coral and deplete essential fish populations.

Innovative efforts to save coral reefs

The Global Coral Reef Monitoring Network reports that between 2009 and 2018, about 14% of the world’s coral reefs were lost because of large-scale bleaching events. The World Economic Forum says that figure could be 99% by the 2030s because of marine heatwaves. But around the world, governments, businesses and nongovernmental organizations are fighting back.

• In India, Reef Watch preserves reefs in the Andaman and Nicobar Islands by transplanting broken coral onto artificial structures.
• In Tanzania, the Mnemba Coral Reef Restoration project uses similar methods, transplanting over 7,000 micro-colonies onto degraded reefs. It’s even created six new artificial reefs that use rebar and metal frames to grow coral nurseries.
• In the United States, the  project, run by NOAA and partners, restores corals at seven sites in the . It aims to increase coral cover from 2% to 25%. On the other side of the country, in Hawaii, NOAA released millions of native sea urchins to control invasive algae.

President Biden’s National Strategy for a Sustainable Ocean Economy  (PDF, 929KB), released in June, calls for restoring coral to slow erosion and protect against coastal flooding. It helps communities accurately value the benefits of preserving reefs and coral.

Private companies also contribute. In Indonesia, the Sheba coral restoration project has planted over 19,000 reef stars (artificial frames that help coral grow) to create new reefs. The Global Coral Reef Alliance uses “Biorock” technology to run a small electrical current through seawater to form a hard shell of calcium carbonate, allowing corals to grow quickly on artificial structures.

To help monitor these and other efforts, Google’s AI tool, SurfPerch, helps scientists track reef health by analyzing underwater sounds and images. This provides insights on restoration efforts in Indonesia, the Philippines and the Great Barrier Reef.

The need for action

Saving coral reefs requires global cooperation. The International Coral Reef Initiative , currently chaired by the United States, is a partnership of nations and organizations working together to save coral reefs.

The U.S. Coral Reef Task Force  coordinates coral reef conservation work across U.S. federal, state and territorial governments.

“Earth’s ocean makes life possible. It hosts vibrant ecosystems, feeds billions of people, sustains livelihoods, and connects us all,” said Arati Prabhakar, Biden’s chief adviser on science and technology. With Biden’s new national strategy for preserving the ocean economy, the United States is pointing “the way to work with this precious natural resource to … meet the challenges of the climate crisis and biodiversity loss.”