Ningaloo Reef, located on Australia’s north-western coast, is facing a crisis. A marine heatwave has stressed the corals, causing widespread bleaching. The damage has shocked scientists and environmentalists alike.
Unlike the Great Barrier Reef on the east coast, Ningaloo is less known but equally significant. It is the world’s largest fringing reef and a UNESCO World Heritage Site. Its vibrant corals, manta rays, and whale sharks attract divers and tourists. But this year, it faces unprecedented challenges.
The heatwave that began in 2023 reached the Indo-Pacific, affecting reefs like Ningaloo. By 2024, while the Great Barrier Reef suffered bleaching, Ningaloo was spared. However, by the end of 2024 and into the beginning of 2025, temperatures spiked, causing widespread bleaching.
This heatwave is part of the fourth global bleaching event, which experts say has impacted over 80% of the world’s coral reefs. Dr. Kate Quigley, a leading scientist at the Minderoo Foundation, explained that coral relies on algae for its color and biological processes. When water temperatures rise, the relationship breaks down, leading to bleaching.
Ningaloo’s coral has been exposed to prolonged warmth, and scientists worry it will cause irreversible damage. Dr. Quigley expressed concern, saying, “Water temperatures may have been too high for too long. The corals might not bounce back.”
Experts had hoped temperatures would drop by April, but this didn’t happen. The heat persisted, preventing corals from recovering.
Dr. Tom Holmes, from the Department of Biodiversity, noted that previous warming events allowed coral to recover. This time, the damage may be permanent. His team is conducting surveys to assess the extent of the damage.
Tourists who visited Ningaloo have witnessed the damage firsthand. Jenna-Rae Clark, a British-South African tourist, said, “It was like snorkeling on a corpse. The reef was grey and lifeless. There was nothing.”
Local residents fear that the damage may lead tourists to avoid Ningaloo. Sara Morgillo, a conservation worker, said, “People were devastated after seeing the damage. It’s heartbreaking, but we still run dive tours and show the reef’s beauty.”
Scientists agree that the marine heatwave is caused by climate change, especially rising carbon emissions. NASA reports that the oceans have absorbed 90% of global warming, making them hotter than ever. Last year was the warmest on record.
Despite the heatwave’s impact, fossil fuel projects continue in the region. One of the world’s largest fossil fuel projects, the North West Shelf gas plant, operates nearby. Critics argue that these projects contribute to climate change, worsening the damage to Ningaloo.
Paul Gamblin from the Australian Marine Conservation Society said, “It’s shocking that while places like Ningaloo suffer from climate change, governments still approve new fossil fuel projects. We need to draw a line and stop making the situation worse.”
Scientists are working to understand how to help the reef recover. Dr. Chris Roelfsema from the University of Queensland is mapping Ningaloo using photos and drones. He encourages people to support renewable energy and reduce fossil fuel use to help slow climate change.
In the lab, Dr. Quigley and her team are breeding coral to find the most heat-tolerant varieties. Though they have seen success in the Great Barrier Reef, this method is still in its early stages at Ningaloo.
Dr. Quigley admitted that this approach may not be scalable for all reefs. “The root cause of coral bleaching is carbon emissions, not just local intervention,” she said.
The effects of the marine heatwave on Ningaloo Reef are a clear sign of how climate change is affecting ecosystems. Corals provide vital services, including supporting marine life, protecting coastlines from storms, and supporting the livelihoods of millions of people. It is time to take action before we lose these essential ecosystems.
