On Nonsuch Island — a 14-acre speck in Bermuda’s northeast corner — conservationists recently watched a cahow chick emerge from an artificial concrete burrow, a moment they still celebrate wildly. The cahow is the world’s third-rarest seabird and Bermuda’s national bird, yet for 300 years it was considered gone forever.
Everything about this bird seems designed to push it toward extinction: slow breeding, a coin-flip chance of hatching, and chicks abandoned by their parents before they can even fly. Yet something extraordinary has been unfolding on this tiny island for the past 65 years.
A bird that vanished for three centuries
The cahow’s disappearance is one of ornithology’s strangest chapters. During the early years of British colonial rule in Bermuda, the species vanished from all records and was presumed extinct — gone for roughly 300 years. Then, in the mid-20th century, a small cluster of breeding pairs was found clinging to existence on Nonsuch Island. Just 18 of them.
The biology alone explains how close the species came to permanent erasure. Females lay a single egg, and about half of those eggs never hatch. Adults abandon their chick roughly a week before it can fly, leaving the young bird to instinctively seek food at sea while still mastering flight. Between 28 and 35 percent of fledglings don’t survive their first year, and it takes three to six years for adults to return to the island to breed at all. Every stage of reproduction is a narrow margin.
Nesting in underground burrows or deep rock crevices also makes cahows acutely vulnerable to invasive predators — the same animals that have driven island bird populations to collapse across the world.
David Wingate’s lifelong mission
In 1960, British ornithologist David Wingate became Bermuda’s first conservation officer and immediately set his sights on those 18 pairs. He launched the Cahow Recovery Program, a project that would consume the next several decades of his life.
Among Wingate’s most practical innovations was the artificial concrete nest burrow. Cahows require nesting sites that are completely dark — only deep underground crevices qualify, and natural ones are scarce. So Wingate designed and built concrete structures to replicate them. Today, 85 percent of all cahows nest in these artificial burrows, a quiet engineering solution that underpins the entire recovery.
His ambitions extended well beyond one species, though. Wingate envisioned transforming Nonsuch Island — then largely barren — into what he called a “Living Museum of pre-colonial Bermuda.” That meant restoring native woodland, creating a small freshwater marsh, and systematically removing the invasive species that had stripped the island of its original character. An ecological reimagining of an entire place, driven by one person’s conviction that the cahow’s survival depended on it. The program is now widely recognized as one of the most successful restoration efforts for a critically endangered species anywhere in the world.
From 18 pairs to 450 birds
When Jeremy Madeiros took over from Wingate as the program’s lead, the population had grown to 55 birds — meaningful progress, but still a fragile number. Under Madeiros, that figure has climbed to around 450 birds of all ages. The trajectory has held.
The latest hatching isn’t the first, and it won’t be the last. Conservationists still celebrate it, because each new chick represents a species that, by all historical accounts, shouldn’t exist anymore. Public access to Nonsuch Island remains tightly controlled — visits are organized by Bermuda’s environment ministry for educational and research purposes, a deliberate policy to prevent the accidental introduction of invasive species. For those who can’t visit in person, live camera feeds now offer a window into the island’s burrows.
A whole island reborn
The cahow’s recovery didn’t happen in isolation. Over 65 years, the restoration of Nonsuch Island has drawn back yellow-crowned night herons, West Indian top shells, land hermit crabs, and the Bermuda skink — all repopulating as the habitat recovered. A barren islet has become a functioning pre-colonial ecosystem.
That’s the broader lesson Nonsuch Island offers: single-species conservation programs, when executed with enough patience and ecological thinking, can cascade into something much larger. Saving the cahow required saving the island. Saving the island brought back everything else. The project has since drawn attention from conservation efforts in the Marshall Islands and the Galápagos, where similar questions about island rewilding and invasive species removal are being worked through.
The cahow’s story is, in one sense, a straightforward conservation success — a species pulled back from presumed extinction through sustained human effort. But it raises a quieter question worth sitting with: how many other species were lost before anyone thought to look? The cahow survived because a handful of breeding pairs happened to persist on a remote island, and because someone showed up in 1960 with the will to act. The margin was that thin. What the past 65 years on Nonsuch Island suggest is that recovery is possible — but it rarely happens on its own, and it almost never happens fast.