A coral reef presumed dead for 60 years turns out to be thriving
In the early 1960s, fishing surveys off the coast of Benin picked up what looked like coral formations 52 to 56 meters down, but with only dredging and primitive sonar to go on, scientists concluded the reefs were dead and nobody went back to check for six decades 45.
This year a team led by oceanographer Gérard Zinzindohoué finally did, spending months between April and December 2025 mapping the seafloor with modern side-scan sonar. They found two patches of hard-bottom habitat stretching roughly 7 kilometers, and when they lowered cameras and a remote drone down to look, they found a living coral garden 45. These are mesophotic reefs, sometimes called "twilight reefs," sitting deep enough that only a trickle of sunlight reaches them, which may be exactly why they survived while shallower reefs bleached in the warming water above.