Mauritius Scientists Breed Coral With 98% Heat Survival Rate

When ocean temperatures hit 88°F around Mauritius last summer, wild coral reefs turned ghostly white as 80% bleached from the heat. But Dr. Nadeem Nazurally's experimental coral glowed with color, boasting survival rates that scientists once thought impossible.

The secret? Nazurally and his team are breeding corals the same way farmers breed drought-resistant crops. They're creating a new generation of reef-builders tough enough to survive our warming oceans.

Mauritius, a small island nation off Africa's east coast, hosts nearly 250 coral species that anchor the entire marine ecosystem. These reefs support fisheries worth billions of dollars and provide homes for one-fourth of the island's sea life. Since 1998, devastating bleaching events have struck five times, each one threatening to collapse this underwater foundation.

Traditional restoration methods simply cloned fragments from healthy coral colonies. But as heat waves became more frequent and intense, even the strongest wild corals couldn't keep up. Scientists needed a completely different approach.

Enter the painstaking work of coral breeding. Corals reproduce in perfectly synchronized spawning events that happen across entire reefs in just a few hours on certain nights. Odysseo Oceanarium mastered the art of predicting these rare moments, racing out by boat to collect eggs and sperm as they're released into the water.

In protected nurseries, scientists cross-pollinate corals from parents that survived previous heat waves. The offspring inherit their parents' heat tolerance, creating increasingly resilient generations.

Last summer's bleaching event became the ultimate test. While wild reefs suffered catastrophic losses, the bred corals thrived. The hydrozoan genus Millepora, bred for heat resistance, achieved an astounding 99.8% survival rate. Even other heat-selected coral genera averaged 88% survival, compared to just 10% for corals bred without heat resistance.

The research revealed another breakthrough. Floating platforms protected young corals from damaging sediment in tourist-heavy areas, while seabed nurseries worked better in quieter zones. This dual approach means scientists can restore reefs regardless of location.

The Ripple Effect

Mauritius is now exporting this knowledge worldwide. As coral reefs from Australia to the Caribbean face similar threats, the island's breeding techniques offer a roadmap for survival. Organizations like the Mauritius Oceanography Institute and University of Mauritius are sharing their methods with marine scientists globally.

The work proves that we're not helpless against climate change's impact on ocean ecosystems. With government and UN support fueling expansion, these heat-resistant corals could seed reef restoration projects across the tropics.

The ocean's most vibrant ecosystems now have a fighting chance, bred for resilience one generation at a time.