Coral reef thought to be dead for 60 years found alive off Africa's Benin coast. Scientists spot fish and coral deep underwater

For more than six decades, scientists believed a coral reef off the coast of Benin was dead. Then researchers returned with modern sonar and underwater cameras and found living coral communities more than 50 metres below the surface, along with several species of reef fish. The discovery is giving scientists a new look at a part of West Africa's ocean that has remained largely unexplored. It also raises a bigger question: how many underwater ecosystems could still be hiding in places scientists have barely surveyed?

Scientists Returned To A Reef First Reported In The 1960s

The reef was first recorded during surveys carried out in 1963 and 1964 along the Benin-Togo continental shelf. Those surveys were mainly focused on finding fishing grounds and studying fish, rather than examining coral ecosystems. Researchers reported a possible coral reef at depths of around 52 to 56 metres but assumed that the coral was dead. No further research specifically targeting the reef was carried out for decades. In 2025, a research team returned to the area as part of the Coral Reefs Rediscovery and Exploration project in Benin. They used side-scan sonar to examine the seafloor before sending underwater imaging equipment to investigate promising locations.

Underwater Cameras Revealed Living Coral

The new surveys covered about 7 kilometres of the seafloor and identified two areas that appeared to contain hard underwater structures. When scientists examined selected locations with an underwater drone and a stationary Deep Sea Camera, they found living coral communities at about 54 metres deep.


The researchers recorded at least six different types of soft coral, two types of black coral and eight species of reef-associated fish. The fish were seen using the coral habitat for shelter and feeding. The scientists describe the discovery as a mesophotic coral ecosystem. These ecosystems exist in deeper parts of the ocean where sunlight is limited and are much less studied than shallow coral reefs.

'It Was A Mix Of Excitement And Disbelief'

Lead researcher Gérard Zinzindohoué of Benin's Institut de Recherches Halieutiques et Océanologiques described the expedition as difficult, with long days at sea, technical problems and uncertainty about what the team would find. Speaking about the moment the underwater cameras revealed the seafloor, he said it was “a mix of excitement and disbelief” because researchers had spent so long wondering about the reef. The findings were published in Frontiers in Marine Science. The researchers say this is the first confirmed visual evidence of living mesophotic coral communities on the Benin continental shelf and, to their knowledge, the first documented example on the Gulf of Guinea continental shelf.

The Reef May Be Much Bigger

There is still a lot that scientists do not know about the ecosystem. The historical reports suggested that the possible reef system could extend for roughly 40 kilometres along the coast. However, the new team has examined only a small part of that area. Researchers also have not yet collected physical coral samples, meaning species identifications from the camera footage remain provisional. Zinzindohoué told ScienceDaily that the discovery may be a sign of how little is known about West Africa's coastal waters. “If we were able to find this reef again after 60 years, how many others are still undocumented or simply forgotten?” he said.

A Hidden Ocean World May Still Be Waiting

The discovery does not prove that the entire reef once thought dead has survived unchanged for 60 years. Scientists say they cannot yet determine whether the coral was already alive in the 1960s and was simply misinterpreted, or whether some areas recovered later. More surveys and physical sampling will be needed to answer that question. For now, the finding offers a striking reminder of how much remains hidden beneath the ocean surface. A reef that had effectively disappeared from scientific attention has turned out to support living coral and fish and researchers now want to know what else may be waiting to be discovered nearby.