World’s largest coral colony discovered off Australian coast by mother-daughter team
A mother-daughter team of citizen scientists has identified the world’s largest known coral colony, found on the Great Barrier Reef off the coast of Australia.
It stretches about 111 meters (364 feet) — about the same length as a football field — and covers about 3,973 square meters (42,765 feet), according to a statement released Tuesday by the conservation organization Citizens of the Reef.
This means it is “one of the most significant coral structures ever recorded on the Great Barrier Reef” and “the largest documented and mapped coral colony in the world,” according to the organization.
The coral was discovered late last year by Sophie Kalkowski-Pope, marine operations coordinator at Citizens of the Reef, and her mother, Jan Pope, an experienced diver and underwater photographer.
The coral is about the same length as a football field. – Jan Pope/Citizens of the Reef
Pope had dove the site a week before and knew she had seen something special. So the couple returned with measuring equipment.
“When we jumped into the water, I could immediately recognize the significance of what we were seeing,” Kalkowski-Pope said. Together, they filmed a video, swimming across the expanse of J-shaped coral. “It took me a three-minute video just to swim from one side to the other,” Kalkowski-Pope said.
The size of the Pavona clavus coral was verified using manual underwater measurements and high-resolution images taken from platforms on the water surface.
This data was then used to produce a 3D model of the coral, according to Citizens of the Reef.
Jan Pope and her daughter Sophie Kalkowski-Pope discovered the enormous coral late last year. – Citizens of the Reef
This type of spatial modeling is useful for monitoring the site and its evolution, because it “means we can come back in the coming months and years and make direct, individual comparisons to understand how the coral is changing over time,” said Serena Mou, a research engineer at the Queensland University of Technology’s Robotics Centre.
The site has been found to be subject to strong tidal currents and low exposure to tropical cyclone waves compared to many other parts of the Great Barrier Reef, and scientists are currently investigating whether these conditions could play a role in the existence of such a large coral structure.
Scientists have now created a 3D model of the coral. – Richard Fitzpatrick/Citizens of the Reef
The exact location of the coral was not disclosed, to “reduce the risk of unintended impacts,” Citizens of the Reef said.
Australia’s Great Barrier Reef is the largest living structure on the planet and is home to a vast range of species. But in recent years it has been hit by a series of devastating mass bleaching events, turning the vibrant colors of parts of the reef to a dazzling white.
Corals around the world are suffering a similar fate, with more than 80% of ocean reefs affected by an ongoing global bleaching phenomenon that began in 2023, due to record sea temperatures. Bleaching can be deadly because corals are devoid of the algae that live inside and serve as a food source.
Citizens of the Reef is part of conservation efforts to protect the reef, and the mother-daughter team was monitoring the reef from the family boat as part of the Great Reef Census, a joint effort to collect images of the reef involving more than 100 vessels.
The Great Reef census involves more than 100 ships. – Citizens of the Reef
“The large reef census helps us locate the most important sources of reef recovery, helping scientists and managers better target their protection,” Pete Mumby of the Marine Spatial Ecology Lab at the University of Queensland said in the release.
The initiative is part of efforts to involve “people power” in conservation efforts, Andy Ridley, CEO of Citizens of the Reef, said in the release.
“The Great Reef Census was developed to complement existing monitoring programs by collecting data on a large scale,” he said.
“This is made possible by people already on the water, like Sophie and Jan, and by thousands of citizen scientists around the world.”
EDITOR’S NOTE: Call to Earth is a CNN editorial series committed to reporting on the environmental challenges facing our planet, as well as the solutions. Rolex’s Perpetual Planet initiative has partnered with CNN to raise awareness and educate on key sustainability issues and to inspire positive action.
CNN’s Nell Lewis contributed to this report.
For more CNN news and newsletters, create an account at CNN.com
