Mother-Daughter Duo Discovers World's Largest Coral Colony on the Great Barrier Reef

Sometimes the biggest discoveries come from the people who love the ocean most. Jan Pope, a veteran diver with 35 years of experience, and her daughter Sophie Kalkowski-Pope have discovered what scientists believe is the world's largest documented coral colony — a single, sprawling organism on the Great Barrier Reef near Cairns, Queensland. The colony, a massive formation of Pavona clavus (commonly known as 'elephant skin' coral for its wrinkled, plate-like texture), stretches approximately 364 feet long — roughly the size of a professional soccer field — covering more than 4,000 square metres. The discovery was made as part of the Great Reef Census, a citizen-led initiative that uses over 100 vessels to survey and document the 2,300-kilometre-long reef system. Jan first spotted the unusual formation during a dive late last year, describing it as a 'very surreal underwater landscape' that resembled a 'rolling meadow.' 'When we jumped into the water, I could immediately understand the significance of what we were seeing,' Kalkowski-Pope told CNN. She noted that it took a continuous three-minute video to swim from one end of the J-shaped colony to the other. Researchers verified the megacolony's scale using manual underwater measurements and high-resolution surface imagery. Engineers from Queensland University of Technology then created a high-fidelity 3D model of the structure, enabling long-term monitoring. 'This allows us to go back in the coming months and years to make direct comparisons to understand how the coral is changing over time,' said Serena Mou, a research engineer involved in the mapping project. Dr Tom Bridge, curator of corals at the Queensland Museum, noted that further genetic testing is needed to confirm whether the giant is a single organism or a cluster of closely connected colonies. Either way, the sheer scale is unprecedented. The discovery carries a deeper significance. At a time when coral reefs worldwide face existential threats from ocean warming, bleaching events, and acidification, finding a thriving megacolony is a powerful reminder that nature's resilience can still surprise us. And the fact that it was found by a mother and daughter — citizen scientists volunteering their time to document the reef they love — makes this story even more special. Science doesn't always happen in laboratories. Sometimes it happens when two people who care deeply about the ocean put on their fins and dive in. 🪸