Sixty years after surveyors first uncovered evidence of a sprawling coral reef off the West African nation of Benin, scientists have at last found the reef. In the 1960s, fishing surveyors off West Africa’s Benin coast hauled up heads of coral in their nets. Employed by local governments to assess fish diversity and discover potentially trawlable seabeds in the sandy-bottomed Gulf of Guinea, the researchers shrugged off the discovery at the time, burying the find in a brief paragraph in a 130-something-page report.

With no surveys since, the scientists who followed had lost track of exactly where the reefs might lie. And as mass bleaching events and overfishing slashed the world’s coral reef area by more than 50 percent since the 1950s, local oceanographers had written off any remnants of a possible reef as dead. More than six decades on, the mystery has been solved as a team of Beninese scientists rediscovered the healthy reef teeming with marine life.

At least eight coral types and eight fish species have formed a thriving ecosystem on this long-forgotten site. “I was guided by hope. A hope that sometimes there are species or ecosystems which kind of defeat time, or are trying to resist it,” said Gérard Zinzindohoué, the project lead for Coral Reefs Rediscovering & Exploration in Benin.

Fresh off seeing coral for the first time in Cape Verde in 2021, Zinzindohoué asked himself a simple question: Do we have any reefs in Benin? After a colleague passed on the original 1960s report — which mapped out a potential 24-mile-long coral reef barrier along Benin’s coastline — Zinzindohoué recognized a gap in the scientific knowledge: “I realized how little we know about our own coastal environment.” But in the years that followed, a string of failed grant applications halted progress on solving the mystery. When he secured a $20,000 National Geographic Explorers grant in January 2025, the project finally ignited.

Yet getting the gear was also challenging. The sonar equipment swallowed up almost 80 percent of the grant budget and nearly stalled entirely when the European supplier refused to accept payment from Zinzindohoué’s African bank account. To complicate matters further, Benin doesn’t have a permanent research vessel.

Zinzindohoué therefore had no choice but to seek the help of local fishermen to ferry the team to the suspected site 14 miles offshore and jury-rig the pirogue to accommodate towing the high-tech sonar device. “The fishermen’s boats are not used to going that far offshore, so it was risky for everyone,” said Zinzindohoué, whose team battled repeated engine failures and months of nausea-filled fieldwork before finally locating two strong sonar echoes pinging from the depths below. National Geographic — whom Zinzindohoué credits with the success of the project — then dispatched a high-resolution deep-sea camera system from their Exploration Technology Lab to investigate the sonar results.

While their wooden pirogue bounced atop the offshore swell, the team filmed the seafloor below but had to wait until they returned to dry land to scour the footage. What they had captured was a wealth of marine life: six types of soft coral; two black corals; and eight species of sheltering fish, from golden African snappers to the Monrovia doctorfish.