A mother-daughter team of citizen scientists has uncovered what may be the world's largest coral colony on Australia's Great Barrier Reef. The Pavona clavus structure spans 111 metres and covers nearly 4,000 square metres offshore from Cairns. Experts hail the find as a sign of resilience amid rising threats from climate change.
Jan Pope and her daughter Sophie Kalkowski-Pope spotted the massive Pavona clavus coral during a dive as part of the Great Reef Census, a citizen science initiative by Citizens of the Reef. The discovery occurred late last year in waters a few hours offshore from Cairns in Far North Queensland, with the pair returning in January to map it using drones, measuring tapes, and 3D modeling in collaboration with researchers at Queensland University of Technology.
The colony measures 111 metres in length with an estimated footprint of 3,971 square metres—roughly half the size of a soccer field. Sophie Kalkowski-Pope, a marine operations coordinator at the charity, described it as "meadows of rippling coral as far as the eye can see." Her mother, Jan Pope, recalled, "When I got in the water, I'd never seen coral growing like this before. It looked like a meadow of coral. It just went on and on."
Experts estimate the colony is at least a couple of hundred years old. Mike Emslie from the Australian Institute of Marine Science praised the detailed measurements, noting it indicates some corals are enduring mass bleaching, cyclones, and crown-of-thorns starfish outbreaks. "This kind of report is only a good thing for raising the profile of the reef," he said. James Cook University marine scientist Allison Paley called it "quite impressive" and highlighted the value of citizen science programs.
The site, characterized by strong tidal currents and low cyclonic wave exposure, remains undisclosed to protect it. The Great Barrier Reef Marine Park Authority will monitor and manage the area. While the find offers hope for resilient pockets in deeper, cooler waters, scientists stress it does not signal overall reef recovery amid increasing bleaching from global heating. Sophie Kalkowski-Pope emphasized, "Discoveries like this are significant because the reef still holds so many unknowns, and we don't know what we stand to lose."